usr/src/cmd/ypcmd/yppasswd/yppasswdd.c

   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, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*
  23  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 #pragma ident   "%Z%%M% %I%     %E% SMI"
  28
  29 #include <stdio.h>
  30 #include <stdlib.h>
  31 #include <unistd.h>
  32 #include <signal.h>
  33 #include <fcntl.h>
  34 #include <ctype.h>
  35 #include <string.h>
  36 #include <syslog.h>
  37 #include <crypt.h>
  38 #include <errno.h>
  39 #include <tiuser.h>
  40 #include <netdir.h>
  41 #include <pwd.h>
  42 #include <shadow.h>
  43 #include <sys/types.h>
  44 #include <sys/stat.h>
  45 #include <sys/wait.h>
  46 #include <sys/resource.h>
  47 #include <rpc/rpc.h>
  48 #include <rpc/pmap_clnt.h>
  49 #include <rpcsvc/yppasswd.h>
  50 #include <netconfig.h>
  51 #include <deflt.h>
  52
  53 /* N2L includes */
  54 #include <ndbm.h>
  55 #include "shim.h"
  56 #include "yptol.h"
  57
  58 /* must match sizes in passwd */
  59 #define STRSIZE 100
  60
  61 #define DEFDIR "/etc/"
  62 #define MYPASSWD "passwd"
  63 #define MYSHADOW "shadow"
  64 #define DEFAULT_YPPASSWDD "/etc/default/yppasswdd"
  65 #define YPPASSWDD_STR "check_restricted_shell_name=1"
  66
  67 /* The guts are in there */
  68 extern void changepasswd(SVCXPRT *);
  69
  70 static void     boilerplate(struct svc_req *rqstp, SVCXPRT *transp);
  71 static void     unlimit(int lim);
  72 bool_t          validloginshell(char *sh, char *arg, int);
  73 int             validstr(char *str, size_t size);
  74
  75 extern char  *getusershell(void);
  76 extern void   setusershell(void);
  77 extern void   endusershell(void);
  78
  79 int  Argc;
  80 char **Argv;
  81 int  mflag;                     /* do a make */
  82 int Mstart;
  83 int single = 0;
  84 int nogecos = 0;
  85 int noshell = 0;
  86 int nopw = 0;
  87 int useadjunct = 0;
  88 int useshadow = 0;
  89
  90 static char *defshell = "/bin/sh";
  91
  92 /* These are the various reasons we might exit. */
  93 enum exitstat {
  94     Esuccess,
  95     EminusDandfiles,
  96     Emissingdir,
  97     Emissingadjunct,
  98     Eaccesspasswd,
  99     Eaccessshadow,
 100     Echdir,
 101     Egetnetconfigent,
 102     Et_open,
 103     Enetdir_rsvdport,
 104     Et_sync,
 105     Et_info,
 106     Esvc_create,
 107     Esvc_reg,
 108     Esvcrun_ret,
 109     ElockFail,
 110     EparseFail
 111 };
 112
 113 static char err_usage[] =
 114 "Usage:\n"
 115 "        rpc.yppasswdd [-D directory | passwd [passwd.adjunct]]\n"
 116 "                      [-nopw] [-nogecos]\n"
 117 "                      [-noshell] [-m arg1 arg2 ...]\n"
 118 "where\n"
 119 "        directory is the directory where the passwd, shadow and/or\n"
 120 "        passwd.adjunct files are found (/etc by default)\n"
 121 "        It should match the setting of PWDIR in /var/yp/Makefile\n\n"
 122 "        Alternatively, the old 4.1.x syntax is supported where\n"
 123 "        passwd is the path to the passwd file\n"
 124 "        passwd.adjunct is the patch to the passwd.adjunct file\n"
 125 "        NOTES:\n"
 126 "         1. The -D option and the passwd/passwd.adjunct arguments are\n"
 127 "            mutually exclusive\n"
 128 "         2. The old syntax deprecated and will be removed in a future\n"
 129 "            release\n"
 130 "         3. A shadow file found in the same directory as the passwd\n"
 131 "            will be assumed to contain the password information\n\n"
 132 "        arguments after -m are passed to make(1S) after password changes\n"
 133 "        -nopw passwords may not be changed remotely using passwd\n"
 134 "        -nogecos full name may not be changed remotely using passwd or chfn\n"
 135 "        -noshell shell may not be changed remotely using passwd or chsh\n";
 136
 137 char passwd_file[FILENAME_MAX], shadow_file[FILENAME_MAX];
 138 char lockfile[FILENAME_MAX], adjunct_file[FILENAME_MAX];
 139
 140 int
 141 main(int argc, char **argv)
 142 {
 143         SVCXPRT *transp4, *transp6, *transpl;
 144         struct netconfig *nconf4, *nconf6, *nconfl;
 145         int i, tli4, tli6, stat;
 146         int errorflag;
 147         int dfexcl; /* -D or files, not both flag */
 148         enum exitstat exitstatus = Esuccess;
 149         int connmaxrec = RPC_MAXDATASIZE;
 150
 151         strcpy(passwd_file, DEFDIR MYPASSWD);
 152         strcpy(shadow_file, DEFDIR MYSHADOW);
 153         strcpy(lockfile, DEFDIR ".pwd.lock");
 154         strcpy(adjunct_file, DEFDIR "security/passwd.adjunct");
 155
 156         Argc = argc;
 157         Argv = argv;
 158
 159         for (i = 1, errorflag = 0, dfexcl = 0; i < argc; i++) {
 160                 if (argv[i][0] == '-' && argv[i][1] == 'm') {
 161                     if (access("/usr/ccs/bin/make", X_OK) < 0)
 162                         fprintf(stderr,
 163                                 "%s: /usr/ccs/bin/make is not available, "
 164                                 "ignoring -m option",
 165                                 argv[0]);
 166                     else {
 167                         mflag++;
 168                         Mstart = i;
 169                         break;
 170                     }
 171                 } else if (argv[i][0] == '-' && argv[i][1] == 'D') {
 172                     switch (dfexcl) {
 173                     case 0:
 174                         if (++i < argc) {
 175                             strcpy(passwd_file, argv[i]);
 176                             strcpy(shadow_file, argv[i]);
 177                             strcpy(adjunct_file, argv[i]);
 178                             strcpy(lockfile, argv[i]);
 179                             if (argv[i][strlen(argv[i]) - 1] == '/') {
 180                                 strcat(passwd_file, MYPASSWD);
 181                                 strcat(shadow_file, MYSHADOW);
 182                                 strcat(lockfile, ".pwd.lock");
 183                                 strcat(adjunct_file, "security/passwd.adjunct");
 184                             } else {
 185                                 strcat(passwd_file, "/" MYPASSWD);
 186                                 strcat(shadow_file, "/" MYSHADOW);
 187                                 strcat(lockfile, "/.pwd.lock");
 188                                 strcat(adjunct_file,
 189                                         "/security/passwd.adjunct");
 190                             }
 191                             dfexcl++;
 192                         } else {
 193                             fprintf(stderr,
 194                                 "rpc.yppasswdd: -D option requires a "
 195                                 "directory argument\n");
 196                             errorflag++;
 197                             exitstatus = Emissingdir;
 198                         }
 199                         break;
 200                     case 1:
 201                         fprintf(stderr,
 202                                 "rpc.yppasswdd: cannot specify passwd/"
 203                                 "passwd.adjunct pathnames AND use -D\n");
 204                         errorflag++;
 205                         dfexcl++;
 206                         exitstatus = EminusDandfiles;
 207                         break;
 208                     default:
 209                         break;
 210                     }
 211         /* -single: Allow user to change only one of password,  */
 212         /*              shell, or full name at a time.  (WHY?)  */
 213         /*      else if (strcmp(argv[i], "-single") == 0)       */
 214         /*          single = 1;                                 */
 215         /*      else if (strcmp(argv[i], "-nosingle") == 0)     */
 216         /*          single = 0;                                 */
 217                 } else if (strcmp(argv[i], "-nogecos") == 0)
 218                     nogecos = 1;
 219                 else if (strcmp(argv[i], "-nopw") == 0)
 220                     nopw = 1;
 221                 else if (strcmp(argv[i], "-noshell") == 0)
 222                     noshell = 1;
 223                 else if (argv[i][0] != '-') {
 224                         /*
 225                          * If we find a shadow file, we warn that we're
 226                          * using it in addition to warning that the user
 227                          * it using a deprecated syntax.
 228                          */
 229                     errorflag++;
 230                     switch (dfexcl) {
 231                     case 0:
 232                         strcpy(passwd_file, argv[i]);
 233                         memset(shadow_file, 0, sizeof (shadow_file));
 234                         strncpy(shadow_file, argv[i],
 235                                 strrchr(argv[i], '/') - argv[i] + 1);
 236                         strcat(shadow_file, MYSHADOW);
 237                         fprintf(stderr,
 238                                 "rpc.yppasswdd: specifying the password file"
 239                                 " on the command line is \n"
 240                                 "               obsolete, "
 241                                 "consider using the -D option instead.\n");
 242                         if (access(shadow_file, F_OK) == 0) {
 243                             fprintf(stderr,
 244                                     "rpc.yppasswdd: found a shadow file in "
 245                                     "the same directory as %s\n"
 246                                     "               It will be used.\n",
 247                                     passwd_file);
 248                         }
 249                         if (i + 1 < argc && argv[i+1][0] != '-') {
 250                             strcpy(adjunct_file, argv[++i]);
 251                             if (access(adjunct_file, F_OK) != 0) {
 252                                 fprintf(stderr,
 253                                         "rpc.yppasswdd: adjunct file %s "
 254                                         "not found\n",
 255                                         adjunct_file);
 256                                 exitstatus = Emissingadjunct;
 257                             }
 258                         }
 259                         dfexcl++;
 260                         break;
 261                     case 1:
 262                         fprintf(stderr,
 263                                 "rpc.yppasswdd: cannot specify passwd/"
 264                                 "passwd.adjunct pathnames AND use -D\n");
 265                         dfexcl++;
 266                         exitstatus = EminusDandfiles;
 267                         break;
 268                     default:
 269                         break;
 270                     }
 271                 } else {
 272                     errorflag++;
 273                     fprintf(stderr,
 274                             "rpc.yppasswdd: unrecognized option %s ignored\n",
 275                             argv[i]);
 276                 }
 277         }
 278
 279         if (errorflag)
 280                 fprintf(stderr, err_usage);
 281
 282         if (exitstatus)
 283                 exit(exitstatus);
 284
 285         if (access(passwd_file, W_OK) < 0) {
 286                 fprintf(stderr, "rpc.yppasswdd: can't access %s\n",
 287                         passwd_file);
 288                 exitstatus = Eaccesspasswd;
 289         }
 290         if (access(shadow_file, W_OK) == 0) {
 291                 useshadow = 1;
 292         } else {
 293                 /* We don't demand a shadow file unless we're looking at /etc */
 294                 if (strcmp(DEFDIR MYSHADOW, shadow_file) == 0) {
 295                     fprintf(stderr, "rpc.yppasswdd: can't access %s\n",
 296                                 shadow_file);
 297                     exitstatus = Eaccessshadow;
 298                 }
 299         }
 300         if (access(adjunct_file, W_OK) == 0) {
 301                 /* using an adjunct file */
 302                 useadjunct = 1;
 303         }
 304
 305         if (chdir("/var/yp") < 0) {
 306                 fprintf(stderr, "rpc.yppasswdd: can't chdir to /var/yp\n");
 307                 exitstatus = Echdir;
 308         }
 309
 310         if (exitstatus)
 311                 exit(exitstatus);
 312
 313         if (errorflag)
 314                 fprintf(stderr, "\nProceeding.\n");
 315
 316
 317         /*
 318          * Initialize locking system.
 319          * This is required for N2L version which accesses the DBM files.
 320          * For the non N2L version this sets up some locking which, since non
 321          * N2L mode does not access the DBM files, will be unused.
 322          *
 323          * This also sets up yptol_mode.
 324          */
 325         if (!init_lock_system(TRUE)) {
 326                 fprintf(stderr,
 327                         "rpc.yppasswdd: Cant initialize locking system\n");
 328                 exit(ElockFail);
 329         }
 330
 331 #ifndef DEBUG
 332         /* Close everything, but stdin/stdout/stderr */
 333         closefrom(3);
 334 #endif
 335
 336         if (yptol_mode) {
 337                 stat = parseConfig(NULL, NTOL_MAP_FILE);
 338                 if (stat == 1) {
 339                         fprintf(stderr, "yppasswdd : NIS to LDAP mapping"
 340                                                         " inactive.\n");
 341                 } else if (stat != 0) {
 342                         fprintf(stderr, "yppasswdd : Aborting after NIS to LDAP"
 343                                                         " mapping error.\n");
 344                         exit(EparseFail);
 345                 }
 346         }
 347
 348 #ifndef DEBUG
 349         /* Wack umask that we inherited from parent */
 350         umask(0);
 351
 352         /* Be a midwife to ourselves */
 353         if (fork())
 354                 exit(Esuccess);
 355
 356         /* Disassociation is hard to do, la la la */
 357         setpgrp();
 358         setsid();
 359
 360         /* Ignore stuff */
 361         signal(SIGHUP, SIG_IGN);
 362         signal(SIGINT, SIG_IGN);
 363         signal(SIGWINCH, SIG_IGN);
 364         signal(SIGTSTP, SIG_IGN);
 365         signal(SIGTTIN, SIG_IGN);
 366         signal(SIGTTOU, SIG_IGN);
 367         signal(SIGCHLD, SIG_IGN);
 368
 369         /*
 370          * Just in case that wasn't enough, let's fork
 371          * again.  (per Stevens).
 372          */
 373         if (fork())
 374                 exit(Esuccess);
 375
 376         /*
 377          * We need stdin, stdout, and stderr later when we
 378          * fork a make(1).
 379          */
 380         freopen("/dev/null", "r+", stdin);
 381         freopen("/dev/null", "r+", stdout);
 382         freopen("/dev/null", "r+", stderr);
 383 #endif
 384
 385         openlog("yppasswdd", LOG_CONS | LOG_PID, LOG_AUTH);
 386         unlimit(RLIMIT_CPU);
 387         unlimit(RLIMIT_FSIZE);
 388
 389         /*
 390          * Set non-blocking mode and maximum record size for
 391          * connection oriented RPC transports.
 392          */
 393         if (!rpc_control(RPC_SVC_CONNMAXREC_SET, &connmaxrec)) {
 394                 syslog(LOG_INFO, "unable to set maximum RPC record size");
 395         }
 396
 397         nconf4 = getnetconfigent("udp");
 398         nconf6 = getnetconfigent("udp6");
 399         if (nconf4 == 0 && nconf6 == 0) {
 400                 syslog(LOG_ERR, "udp/udp6 transport not supported\n");
 401                 exit(Egetnetconfigent);
 402         }
 403
 404         tli4 = (nconf4 != 0) ? t_open(nconf4->nc_device, O_RDWR, NULL) : -1;
 405         tli6 = (nconf6 != 0) ? t_open(nconf6->nc_device, O_RDWR, NULL) : -1;
 406
 407         if (tli4 == -1 && tli6 == -1) {
 408                 syslog(LOG_ERR, "can\'t open TLI endpoint(s)\n");
 409                 exit(Et_open);
 410         }
 411
 412         if (tli4 != -1) {
 413                 if (netdir_options(nconf4, ND_SET_RESERVEDPORT, tli4, NULL)) {
 414                         syslog(LOG_ERR, "could not set reserved port: %s\n",
 415                                 netdir_sperror());
 416                         exit(Enetdir_rsvdport);
 417                 }
 418         }
 419         if (tli6 != -1) {
 420                 if (netdir_options(nconf6, ND_SET_RESERVEDPORT, tli6, NULL)) {
 421                         syslog(LOG_ERR, "could not set reserved port: %s\n",
 422                                 netdir_sperror());
 423                         exit(Enetdir_rsvdport);
 424                 }
 425         }
 426 #ifdef  DEBUG
 427         {
 428                 int i, tli[2];
 429                 char *label[2] = {"udp", "udp6"};
 430                 int state;
 431                 struct t_info tinfo;
 432
 433                 tli[0] = tli4;
 434                 tli[1] = tli6;
 435
 436                 for (i = 0; i < sizeof (tli)/sizeof (tli[0]); i++) {
 437                         fprintf(stderr, "transport %s, fd = %d\n",
 438                                 tli[i], label[i]);
 439                         if ((state = t_sync(tli[i])) < 0) {
 440                                 fprintf(stderr, "t_sync failed: %s\n",
 441                                         t_errlist[t_errno]);
 442                                 exit(Et_sync);
 443                         }
 444                         if (t_getinfo(tli[i], &tinfo) < 0) {
 445                                 fprintf(stderr, "t_getinfo failed: %s\n",
 446                                         t_errlist[t_errno]);
 447                                 exit(Et_info);
 448                         }
 449
 450                         switch (state) {
 451                         case T_UNBND:
 452                                 fprintf(stderr, "TLI is unbound\n");
 453                                 break;
 454                         case T_IDLE:
 455                                 fprintf(stderr, "TLI is idle\n");
 456                                 break;
 457                         case T_INREL:
 458                                 fprintf(stderr,
 459                                         "other side wants to release\n");
 460                                 break;
 461                         case T_INCON:
 462                                 fprintf(stderr, "T_INCON\n");
 463                                 break;
 464                         case T_DATAXFER:
 465                                 fprintf(stderr, "T_DATAXFER\n");
 466                                 break;
 467                         default:
 468                                 fprintf(stderr, "no state info, state = %d\n",
 469                                         state);
 470                         }
 471                 }
 472         }
 473 #endif
 474         if (tli4 != -1) {
 475                 rpcb_unset((ulong_t)YPPASSWDPROG, (ulong_t)YPPASSWDVERS,
 476                         nconf4);
 477                 transp4 = svc_tli_create(tli4, nconf4, NULL, 0, 0);
 478         } else {
 479                 transp4 = 0;
 480         }
 481         if (tli6 != -1) {
 482                 rpcb_unset((ulong_t)YPPASSWDPROG, (ulong_t)YPPASSWDVERS,
 483                         nconf6);
 484                 transp6 = svc_tli_create(tli6, nconf6, NULL, 0, 0);
 485         } else {
 486                 transp6 = 0;
 487         }
 488         if (transp4 == 0 && transp6 == 0) {
 489                 syslog(LOG_ERR, "yppasswdd: couldn't create an RPC server\n");
 490                 exit(Esvc_create);
 491         }
 492         if (transp4 && !svc_reg(transp4, (ulong_t)YPPASSWDPROG,
 493                         (ulong_t)YPPASSWDVERS, boilerplate, nconf4)) {
 494                 syslog(LOG_ERR, "yppasswdd: couldn't register yppasswdd\n");
 495                 exit(Esvc_reg);
 496         }
 497         if (transp6 && !svc_reg(transp6, (ulong_t)YPPASSWDPROG,
 498                         (ulong_t)YPPASSWDVERS, boilerplate, nconf6)) {
 499                 syslog(LOG_ERR, "yppasswdd: couldn't register yppasswdd\n");
 500                 exit(Esvc_reg);
 501         }
 502
 503         /*
 504          * Create a loopback RPC service for secure authentication of local
 505          * principals -- we need this for accepting passwd updates from
 506          * root on the master server.
 507          */
 508         if ((nconfl = getnetconfigent("ticlts")) == NULL) {
 509             syslog(LOG_ERR, "transport ticlts not supported\n");
 510             exit(Egetnetconfigent);
 511         }
 512         rpcb_unset((ulong_t)YPPASSWDPROG, (ulong_t)YPPASSWDVERS, nconfl);
 513         transpl = svc_tli_create(RPC_ANYFD, nconfl, NULL, 0, 0);
 514         if (transpl == NULL) {
 515             syslog(LOG_ERR,
 516                 "yppasswdd: couldn't create an loopback RPC server\n");
 517             exit(Esvc_create);
 518         }
 519         if (!svc_reg(transpl, (ulong_t)YPPASSWDPROG, (ulong_t)YPPASSWDVERS,
 520                         boilerplate, nconfl)) {
 521             syslog(LOG_ERR, "yppasswdd: couldn't register yppasswdd\n");
 522             exit(Esvc_reg);
 523         }
 524         __rpc_negotiate_uid(transpl->xp_fd);
 525         freenetconfigent(nconf4);
 526         freenetconfigent(nconf6);
 527         freenetconfigent(nconfl);
 528         svc_run();
 529         syslog(LOG_ERR, "yppasswdd: svc_run shouldn't have returned\n");
 530
 531         return (Esvcrun_ret);
 532         /* NOTREACHED */
 533 }
 534
 535 static void
 536 boilerplate(struct svc_req *rqstp, SVCXPRT *transp)
 537 {
 538         switch (rqstp->rq_proc) {
 539         case NULLPROC:
 540                 if (!svc_sendreply(transp, xdr_void, (char *)0))
 541                     syslog(LOG_WARNING,
 542                         "yppasswdd: couldn't reply to RPC call\n");
 543                 break;
 544         case YPPASSWDPROC_UPDATE:
 545                 if (yptol_mode)
 546                         shim_changepasswd(transp);
 547                 else
 548                         changepasswd(transp);
 549                 break;
 550         }
 551 }
 552
 553 int
 554 validstr(char *str, size_t size)
 555 {
 556         char c;
 557
 558         if (str == NULL || strlen(str) > size || strchr(str, ':'))
 559                 return (0);
 560         while (c = *str++) {
 561                 if (iscntrl(c))
 562                     return (0);
 563         }
 564         return (1);
 565 }
 566
 567 bool_t
 568 validloginshell(char *pw_shell, char *arg, int privileged)
 569 {
 570         static char newshell[STRSIZE];
 571         char *cp, *valid;
 572
 573         if (pw_shell == 0 || *pw_shell == '\0')
 574                 pw_shell = defshell;
 575
 576         if ((defopen(DEFAULT_YPPASSWDD)) == 0) {
 577                 if ((defread(YPPASSWDD_STR)) != NULL) {
 578                         cp = strrchr(pw_shell, '/');
 579                         if (cp)
 580                                 cp++;
 581                         else
 582                                 cp = pw_shell;
 583
 584                         if (*cp == 'r') {
 585                                 syslog(LOG_ERR,
 586                                         "yppasswdd: cannot change "
 587                                         "from restricted shell %s\n",
 588                                         pw_shell);
 589                                 return (0);
 590                         }
 591                 }
 592                 (void) defopen((char *)NULL);
 593         }
 594
 595         for (valid = getusershell(); valid; valid = getusershell())
 596                 if (strcmp(pw_shell, valid) == 0)
 597                     break;
 598
 599         if (valid == NULL && !privileged) {
 600                 syslog(LOG_ERR, "yppasswdd: Current shell is not valid: %s\n",
 601                         pw_shell);
 602                 endusershell();
 603                 return (0);
 604         }
 605
 606         if (arg != 0) {
 607                 strncpy(newshell, arg, sizeof (newshell) - 1);
 608                 newshell[sizeof (newshell) - 1] = 0;
 609         } else {
 610                 endusershell();
 611                 return (0);
 612         }
 613
 614         /*
 615          * Allow user to give shell name w/o preceding pathname.
 616          */
 617         setusershell();
 618         for (valid = getusershell(); valid; valid = getusershell()) {
 619                 if (newshell[0] == '/') {
 620                     cp = valid;
 621                 } else {
 622                     cp = strrchr(valid, '/');
 623                     if (cp == 0)
 624                         cp = valid;
 625                     else
 626                         cp++;
 627                 }
 628                 if (strcmp(newshell, cp) == 0)
 629                     break;
 630         }
 631
 632         if (valid == 0) {
 633                 if (!privileged || newshell[0] != '/') {
 634                         syslog(LOG_WARNING,
 635                                 "%s is unacceptable as a new shell.\n",
 636                                 newshell);
 637                         endusershell();
 638                         return (0);
 639                 }
 640                 valid = newshell;
 641         }
 642
 643         if (access(valid, X_OK) < 0) {
 644                 syslog(LOG_WARNING, "%s is unavailable.\n", valid);
 645                 endusershell();
 646                 return (0);
 647         }
 648
 649         strncpy(newshell, valid, sizeof (newshell));
 650         pw_shell =  newshell;
 651         endusershell();
 652         return (1);
 653 }
 654
 655 static void
 656 unlimit(int lim)
 657 {
 658         struct rlimit rlim;
 659         rlim.rlim_cur = rlim.rlim_max = RLIM_INFINITY;
 660         setrlimit(lim, &rlim);
 661 }