libc/inet/rpc/rcmd.c

   1 /*
   2  * Copyright (C) 1998 WIDE Project.
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the project nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  */
  29 /*
  30  * Copyright (c) 1983, 1993, 1994
  31  *      The Regents of the University of California.  All rights reserved.
  32  *
  33  * Redistribution and use in source and binary forms, with or without
  34  * modification, are permitted provided that the following conditions
  35  * are met:
  36  * 1. Redistributions of source code must retain the above copyright
  37  *    notice, this list of conditions and the following disclaimer.
  38  * 2. Redistributions in binary form must reproduce the above copyright
  39  *    notice, this list of conditions and the following disclaimer in the
  40  *    documentation and/or other materials provided with the distribution.
  41  * 4. Neither the name of the University nor the names of its contributors
  42  *    may be used to endorse or promote products derived from this software
  43  *    without specific prior written permission.
  44  *
  45  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  46  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  47  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  48  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  49  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  50  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  51  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  52  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  53  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  54  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  55  * SUCH DAMAGE.
  56  */
  57
  58 #if 0
  59 static char sccsid[] = "@(#)rcmd.c      8.3 (Berkeley) 3/26/94";
  60 #endif /* LIBC_SCCS and not lint */
  61
  62 #define __UCLIBC_HIDE_DEPRECATED__
  63 #include <features.h>
  64 #include <sys/param.h>
  65 #include <sys/poll.h>
  66 #include <sys/socket.h>
  67 #include <sys/stat.h>
  68
  69 #include <netinet/in.h>
  70 #include <arpa/inet.h>
  71
  72 #include <signal.h>
  73 #include <fcntl.h>
  74 #include <netdb.h>
  75 #include <unistd.h>
  76 #include <pwd.h>
  77 #include <errno.h>
  78 #include <stdio.h>
  79 #include <ctype.h>
  80 #include <string.h>
  81 #include <stdlib.h>
  82 #ifdef __UCLIBC_HAS_WCHAR__
  83 #include <wchar.h>
  84 #endif
  85 #include <sys/uio.h>
  86 #include <bits/uClibc_alloc.h>
  87
  88 /* sigsetmask and sigblock are not provided anymore, until this file is corrected,
  89  * include the sources */
  90 #include "../../signal/sigblock.c"
  91 #include "../../signal/sigsetmask.c"
  92
  93
  94 /* some forward declarations */
  95 static int __ivaliduser2(FILE *hostf, u_int32_t raddr,
  96                          const char *luser, const char *ruser, const char *rhost);
  97 static int iruserok2 (u_int32_t raddr, int superuser, const char *ruser,
  98                       const char *luser, const char *rhost);
  99
 100
 101 int rcmd(char **ahost, u_short rport, const char *locuser, const char *remuser,
 102                  const char *cmd, int *fd2p)
 103 {
 104 #ifdef __UCLIBC_HAS_REENTRANT_RPC__
 105         int herr;
 106         struct hostent hostbuf;
 107         size_t hstbuflen;
 108         char *tmphstbuf;
 109 #endif
 110         struct hostent *hp;
 111         struct sockaddr_in sin, from;
 112         struct pollfd pfd[2];
 113         int32_t oldmask;
 114         pid_t pid;
 115         int s, lport, timo;
 116         char c;
 117
 118         pid = getpid();
 119
 120 #ifdef __UCLIBC_HAS_REENTRANT_RPC__
 121         hstbuflen = 1024;
 122         tmphstbuf = stack_heap_alloc(hstbuflen);
 123
 124         while (gethostbyname_r (*ahost, &hostbuf, tmphstbuf,
 125                     hstbuflen, &hp, &herr) != 0 || hp == NULL)
 126         {
 127             if (herr != NETDB_INTERNAL || errno != ERANGE)
 128             {
 129                 __set_h_errno (herr);
 130                 stack_heap_free(tmphstbuf);
 131                 herror(*ahost);
 132                 return -1;
 133             }
 134             else
 135             {
 136                 /* Enlarge the buffer.  */
 137                 hstbuflen *= 2;
 138                 stack_heap_free(tmphstbuf);
 139                 tmphstbuf = stack_heap_alloc(hstbuflen);
 140             }
 141         }
 142         stack_heap_free(tmphstbuf);
 143 #else /* call the non-reentrant version */
 144         if ((hp = gethostbyname(*ahost)) == NULL) {
 145             return -1;
 146         }
 147 #endif
 148         pfd[0].events = POLLIN;
 149         pfd[1].events = POLLIN;
 150
 151         *ahost = hp->h_name;
 152         oldmask = sigblock(__sigmask(SIGURG)); /* sigblock */
 153         for (timo = 1, lport = IPPORT_RESERVED - 1;;) {
 154                 s = rresvport(&lport);
 155                 if (s < 0) {
 156                         if (errno == EAGAIN)
 157                             (void)fprintf(stderr,
 158                                           "rcmd: socket: All ports in use\n");
 159                         else
 160                             (void)fprintf(stderr, "rcmd: socket: %m\n");
 161                         sigsetmask(oldmask); /* sigsetmask */
 162                         return -1;
 163                 }
 164                 fcntl(s, F_SETOWN, pid);
 165                 sin.sin_family = hp->h_addrtype;
 166                 memmove(&sin.sin_addr, hp->h_addr_list[0],
 167                       MIN (sizeof (sin.sin_addr), hp->h_length));
 168                 sin.sin_port = rport;
 169                 if (connect(s, (struct sockaddr *)&sin, sizeof(sin)) >= 0) /* __connect */
 170                         break;
 171                 (void)close(s);
 172                 if (errno == EADDRINUSE) {
 173                         lport--;
 174                         continue;
 175                 }
 176                 if (errno == ECONNREFUSED && timo <= 16) {
 177                         (void)sleep(timo); /* __sleep */
 178                         timo *= 2;
 179                         continue;
 180                 }
 181                 if (hp->h_addr_list[1] != NULL) {
 182                         int oerrno = errno;
 183
 184                         (void)fprintf(stderr, "connect to address %s: ",
 185                             inet_ntoa(sin.sin_addr));
 186                         __set_errno (oerrno);
 187                         perror(0);
 188                         hp->h_addr_list++;
 189                         memmove(&sin.sin_addr, hp->h_addr_list[0],
 190                               MIN (sizeof (sin.sin_addr), hp->h_length));
 191                         (void)fprintf(stderr, "Trying %s...\n",
 192                             inet_ntoa(sin.sin_addr));
 193                         continue;
 194                 }
 195                 (void)fprintf(stderr, "%s: %m\n", hp->h_name);
 196                 sigsetmask(oldmask); /* __sigsetmask */
 197                 return -1;
 198         }
 199         lport--;
 200         if (fd2p == 0) {
 201                 write(s, "", 1);
 202                 lport = 0;
 203         } else {
 204                 char num[8];
 205                 int s2 = rresvport(&lport), s3;
 206                 socklen_t len = sizeof(from);
 207
 208                 if (s2 < 0)
 209                         goto bad;
 210                 listen(s2, 1);
 211                 (void)snprintf(num, sizeof(num), "%d", lport); /* __snprintf */
 212                 if (write(s, num, strlen(num)+1) != strlen(num)+1) {
 213                         (void)fprintf(stderr,
 214                                       "rcmd: write (setting up stderr): %m\n");
 215                         (void)close(s2);
 216                         goto bad;
 217                 }
 218                 pfd[0].fd = s;
 219                 pfd[1].fd = s2;
 220                 __set_errno (0);
 221                 if (poll (pfd, 2, -1) < 1 || (pfd[1].revents & POLLIN) == 0){
 222                     if (errno != 0)
 223                         (void)fprintf(stderr, "rcmd: poll (setting up stderr): %m\n");
 224                     else
 225                         (void)fprintf(stderr, "poll: protocol failure in circuit setup\n");
 226                         (void)close(s2);
 227                         goto bad;
 228                 }
 229                 s3 = accept(s2, (struct sockaddr *)&from, &len);
 230                 (void)close(s2);
 231                 if (s3 < 0) {
 232                         (void)fprintf(stderr,
 233                             "rcmd: accept: %m\n");
 234                         lport = 0;
 235                         goto bad;
 236                 }
 237                 *fd2p = s3;
 238                 from.sin_port = ntohs((u_short)from.sin_port);
 239                 if (from.sin_family != AF_INET ||
 240                     from.sin_port >= IPPORT_RESERVED ||
 241                     from.sin_port < IPPORT_RESERVED / 2) {
 242                         (void)fprintf(stderr,
 243                             "socket: protocol failure in circuit setup\n");
 244                         goto bad2;
 245                 }
 246         }
 247         (void)write(s, locuser, strlen(locuser)+1);
 248         (void)write(s, remuser, strlen(remuser)+1);
 249         (void)write(s, cmd, strlen(cmd)+1);
 250         if (read(s, &c, 1) != 1) {
 251                 (void)fprintf(stderr,
 252                     "rcmd: %s: %m\n", *ahost);
 253                 goto bad2;
 254         }
 255         if (c != 0) {
 256                 while (read(s, &c, 1) == 1) {
 257                         (void)write(STDERR_FILENO, &c, 1);
 258                         if (c == '\n')
 259                                 break;
 260                 }
 261                 goto bad2;
 262         }
 263         sigsetmask(oldmask);
 264         return s;
 265 bad2:
 266         if (lport)
 267                 (void)close(*fd2p);
 268 bad:
 269         (void)close(s);
 270         sigsetmask(oldmask);
 271         return -1;
 272 }
 273
 274 int rresvport(int *alport)
 275 {
 276     struct sockaddr_in sin;
 277     int s;
 278
 279     sin.sin_family = AF_INET;
 280     sin.sin_addr.s_addr = INADDR_ANY;
 281     s = socket(AF_INET, SOCK_STREAM, 0);
 282     if (s < 0)
 283         return -1;
 284     for (;;) {
 285         sin.sin_port = htons((u_short)*alport);
 286         if (bind(s, (struct sockaddr *)&sin, sizeof(sin)) >= 0)
 287             return s;
 288         if (errno != EADDRINUSE) {
 289             (void)close(s);
 290             return -1;
 291         }
 292         (*alport)--;
 293         if (*alport == IPPORT_RESERVED/2) {
 294             (void)close(s);
 295             __set_errno (EAGAIN);               /* close */
 296             return -1;
 297         }
 298     }
 299
 300     return -1;
 301 }
 302 libc_hidden_def(rresvport)
 303
 304 /* This needs to be exported ... while it is not a documented interface
 305  * for rcp related apps, it's a required one that is used to control the
 306  * rhost behavior.  Legacy sucks.
 307  */
 308 int  __check_rhosts_file = 1;
 309
 310 int ruserok(const char *rhost, int superuser, const char *ruser,
 311                         const char *luser)
 312 {
 313         struct hostent *hp;
 314         u_int32_t addr;
 315         char **ap;
 316 #ifdef __UCLIBC_HAS_REENTRANT_RPC__
 317         size_t buflen;
 318         char *buffer;
 319         int herr;
 320         struct hostent hostbuf;
 321 #endif
 322
 323 #ifdef __UCLIBC_HAS_REENTRANT_RPC__
 324         buflen = 1024;
 325         buffer = stack_heap_alloc(buflen);
 326
 327         while (gethostbyname_r (rhost, &hostbuf, buffer,
 328                     buflen, &hp, &herr) != 0 || hp == NULL)
 329         {
 330             if (herr != NETDB_INTERNAL || errno != ERANGE) {
 331                 stack_heap_free(buffer);
 332                 return -1;
 333             } else
 334             {
 335                 /* Enlarge the buffer.  */
 336                 buflen *= 2;
 337                 stack_heap_free(buffer);
 338                 buffer = stack_heap_alloc(buflen);
 339             }
 340         }
 341         stack_heap_free(buffer);
 342 #else
 343         if ((hp = gethostbyname(rhost)) == NULL) {
 344                 return -1;
 345         }
 346 #endif
 347         for (ap = hp->h_addr_list; *ap; ++ap) {
 348                 memmove(&addr, *ap, sizeof(addr));
 349                 if (iruserok2(addr, superuser, ruser, luser, rhost) == 0)
 350                         return 0;
 351         }
 352         return -1;
 353 }
 354
 355
 356 /* Extremely paranoid file open function. */
 357 static FILE *
 358 iruserfopen (const char *file, uid_t okuser)
 359 {
 360   struct stat st;
 361   char *cp = NULL;
 362   FILE *res = NULL;
 363
 364   /* If not a regular file, if owned by someone other than user or
 365      root, if writeable by anyone but the owner, or if hardlinked
 366      anywhere, quit.  */
 367   if (lstat (file, &st))
 368     cp = "lstat failed";
 369   else if (!S_ISREG (st.st_mode))
 370     cp = "not regular file";
 371   else
 372     {
 373       res = fopen (file, "r");
 374       if (!res)
 375         cp = "cannot open";
 376       else if (fstat (fileno (res), &st) < 0)
 377         cp = "fstat failed";
 378       else if (st.st_uid && st.st_uid != okuser)
 379         cp = "bad owner";
 380       else if (st.st_mode & (S_IWGRP|S_IWOTH))
 381         cp = "writeable by other than owner";
 382       else if (st.st_nlink > 1)
 383         cp = "hard linked somewhere";
 384     }
 385
 386   /* If there were any problems, quit.  */
 387   if (cp != NULL)
 388     {
 389       if (res)
 390         fclose (res);
 391       return NULL;
 392     }
 393
 394   return res;
 395 }
 396
 397
 398 /*
 399  * New .rhosts strategy: We are passed an ip address. We spin through
 400  * hosts.equiv and .rhosts looking for a match. When the .rhosts only
 401  * has ip addresses, we don't have to trust a nameserver.  When it
 402  * contains hostnames, we spin through the list of addresses the nameserver
 403  * gives us and look for a match.
 404  *
 405  * Returns 0 if ok, -1 if not ok.
 406  */
 407 static int
 408 iruserok2 (u_int32_t raddr, int superuser, const char *ruser, const char *luser,
 409                    const char *rhost)
 410 {
 411         FILE *hostf = NULL;
 412         int isbad = -1;
 413
 414         if (!superuser)
 415                 hostf = iruserfopen (_PATH_HEQUIV, 0);
 416
 417         if (hostf) {
 418                 isbad = __ivaliduser2 (hostf, raddr, luser, ruser, rhost);
 419                 fclose (hostf);
 420
 421                 if (!isbad)
 422                         return 0;
 423         }
 424
 425         if (__check_rhosts_file || superuser) {
 426                 char *pbuf;
 427                 struct passwd *pwd;
 428                 size_t dirlen;
 429                 uid_t uid;
 430
 431 #ifdef __UCLIBC_HAS_REENTRANT_RPC__
 432                 size_t buflen = sysconf (_SC_GETPW_R_SIZE_MAX);
 433                 struct passwd pwdbuf;
 434                 char *buffer = stack_heap_alloc(buflen);
 435
 436                 if (getpwnam_r (luser, &pwdbuf, buffer,
 437                             buflen, &pwd) != 0 || pwd == NULL)
 438                 {
 439                         stack_heap_free(buffer);
 440                         return -1;
 441                 }
 442                 stack_heap_free(buffer);
 443 #else
 444                 if ((pwd = getpwnam(luser)) == NULL)
 445                         return -1;
 446 #endif
 447
 448                 dirlen = strlen (pwd->pw_dir);
 449                 pbuf = malloc (dirlen + sizeof "/.rhosts");
 450                 strcpy (pbuf, pwd->pw_dir);
 451                 strcat (pbuf, "/.rhosts");
 452
 453                 /* Change effective uid while reading .rhosts.  If root and
 454                    reading an NFS mounted file system, can't read files that
 455                    are protected read/write owner only.  */
 456                 uid = geteuid ();
 457                 seteuid (pwd->pw_uid);
 458                 hostf = iruserfopen (pbuf, pwd->pw_uid);
 459                 free(pbuf);
 460
 461                 if (hostf != NULL) {
 462                         isbad = __ivaliduser2 (hostf, raddr, luser, ruser, rhost);
 463                         fclose (hostf);
 464                 }
 465
 466                 seteuid (uid);
 467                 return isbad;
 468         }
 469         return -1;
 470 }
 471
 472 /* This is the exported version.  */
 473 int iruserok (u_int32_t raddr, int superuser, const char * ruser, const char * luser);
 474 int iruserok (u_int32_t raddr, int superuser, const char * ruser, const char * luser)
 475 {
 476         return iruserok2 (raddr, superuser, ruser, luser, "-");
 477 }
 478
 479
 480 /*
 481  * XXX
 482  * Don't make static, used by lpd(8).
 483  *
 484  * This function is not used anymore. It is only present because lpd(8)
 485  * calls it (!?!). We simply call __invaliduser2() with an illegal rhost
 486  * argument. This means that netgroups won't work in .rhost/hosts.equiv
 487  * files. If you want lpd to work with netgroups, fix lpd to use ruserok()
 488  * or PAM.
 489  * Returns 0 if ok, -1 if not ok.
 490  */
 491 int
 492 __ivaliduser(FILE *hostf, u_int32_t raddr, const char *luser, const char *ruser);
 493 int
 494 __ivaliduser(FILE *hostf, u_int32_t raddr, const char *luser, const char *ruser)
 495 {
 496         return __ivaliduser2(hostf, raddr, luser, ruser, "-");
 497 }
 498
 499
 500 /* Returns 1 on positive match, 0 on no match, -1 on negative match.  */
 501 static int
 502 __icheckhost (u_int32_t raddr, char *lhost, const char *rhost)
 503 {
 504         struct hostent *hp;
 505         u_int32_t laddr;
 506         int negate=1;    /* Multiply return with this to get -1 instead of 1 */
 507         char **pp;
 508
 509 #ifdef __UCLIBC_HAS_REENTRANT_RPC__
 510         int save_errno;
 511         size_t buflen;
 512         char *buffer;
 513         struct hostent hostbuf;
 514         int herr;
 515 #endif
 516
 517 #ifdef HAVE_NETGROUP
 518         /* Check nis netgroup.  */
 519         if (strncmp ("+@", lhost, 2) == 0)
 520                 return innetgr (&lhost[2], rhost, NULL, NULL);
 521
 522         if (strncmp ("-@", lhost, 2) == 0)
 523                 return -innetgr (&lhost[2], rhost, NULL, NULL);
 524 #endif /* HAVE_NETGROUP */
 525
 526         /* -host */
 527         if (strncmp ("-", lhost,1) == 0) {
 528                 negate = -1;
 529                 lhost++;
 530         } else if (strcmp ("+",lhost) == 0) {
 531                 return 1;                    /* asking for trouble, but ok.. */
 532         }
 533
 534         /* Try for raw ip address first. */
 535         if (isdigit (*lhost) && (laddr = inet_addr (lhost)) != INADDR_NONE)
 536                 return negate * (! (raddr ^ laddr));
 537
 538         /* Better be a hostname. */
 539 #ifdef __UCLIBC_HAS_REENTRANT_RPC__
 540         buflen = 1024;
 541         buffer = malloc(buflen);
 542         save_errno = errno;
 543
 544         while (gethostbyname_r (lhost, &hostbuf, buffer, buflen, &hp, &herr)
 545                != 0) {
 546             free(buffer);
 547             return (0);
 548         }
 549         free(buffer);
 550         __set_errno (save_errno);
 551 #else
 552         hp = gethostbyname(lhost);
 553 #endif /* __UCLIBC_HAS_REENTRANT_RPC__ */
 554
 555         if (hp == NULL)
 556                 return 0;
 557
 558         /* Spin through ip addresses. */
 559         for (pp = hp->h_addr_list; *pp; ++pp)
 560                 if (!memcmp (&raddr, *pp, sizeof (u_int32_t)))
 561                         return negate;
 562
 563         /* No match. */
 564         return (0);
 565 }
 566
 567 /* Returns 1 on positive match, 0 on no match, -1 on negative match.  */
 568 static int
 569 __icheckuser (const char *luser, const char *ruser)
 570 {
 571
 572     /*
 573       luser is user entry from .rhosts/hosts.equiv file
 574       ruser is user id on remote host
 575       */
 576
 577 #ifdef HAVE_NETGROUP
 578     /* [-+]@netgroup */
 579     if (strncmp ("+@", luser, 2) == 0)
 580         return innetgr (&luser[2], NULL, ruser, NULL);
 581
 582     if (strncmp ("-@", luser,2) == 0)
 583         return -innetgr (&luser[2], NULL, ruser, NULL);
 584 #endif /* HAVE_NETGROUP */
 585
 586     /* -user */
 587     if (strncmp ("-", luser, 1) == 0)
 588         return -(strcmp (&luser[1], ruser) == 0);
 589
 590     /* + */
 591     if (strcmp ("+", luser) == 0)
 592         return 1;
 593
 594     /* simple string match */
 595     return strcmp (ruser, luser) == 0;
 596 }
 597
 598 /*
 599  * Returns 1 for blank lines (or only comment lines) and 0 otherwise
 600  */
 601 static int
 602 __isempty(char *p)
 603 {
 604     while (*p && isspace (*p)) {
 605         ++p;
 606     }
 607
 608     return (*p == '\0' || *p == '#') ? 1 : 0 ;
 609 }
 610
 611 /*
 612  * Returns 0 if positive match, -1 if _not_ ok.
 613  */
 614 static int
 615 __ivaliduser2(FILE *hostf, u_int32_t raddr,     const char *luser,
 616                           const char *ruser, const char *rhost)
 617 {
 618     register const char *user;
 619     register char *p;
 620     int hcheck, ucheck;
 621     char *buf = NULL;
 622     size_t bufsize = 0;
 623     int retval = -1;
 624
 625     while (getline (&buf, &bufsize, hostf) > 0) {
 626         buf[bufsize - 1] = '\0'; /* Make sure it's terminated.  */
 627         p = buf;
 628
 629         /* Skip empty or comment lines */
 630         if (__isempty (p)) {
 631             continue;
 632         }
 633
 634         /* Skip lines that are too long. */
 635         if (strchr (p, '\n') == NULL) {
 636             int ch = getc_unlocked (hostf);
 637
 638             while (ch != '\n' && ch != EOF)
 639               ch = getc_unlocked (hostf);
 640             continue;
 641         }
 642
 643         for (;*p && !isspace(*p); ++p) {
 644             *p = tolower (*p);
 645         }
 646
 647         /* Next we want to find the permitted name for the remote user.  */
 648         if (*p == ' ' || *p == '\t') {
 649             /* <nul> terminate hostname and skip spaces */
 650             for (*p++='\0'; *p && isspace (*p); ++p);
 651
 652             user = p;                   /* this is the user's name */
 653             while (*p && !isspace (*p))
 654                 ++p;                    /* find end of user's name */
 655         } else
 656             user = p;
 657
 658         *p = '\0';              /* <nul> terminate username (+host?) */
 659
 660         /* buf -> host(?) ; user -> username(?) */
 661
 662         /* First check host part */
 663         hcheck = __icheckhost (raddr, buf, rhost);
 664
 665         if (hcheck < 0)
 666             break;
 667
 668         if (hcheck) {
 669             /* Then check user part */
 670             if (! (*user))
 671                 user = luser;
 672
 673             ucheck = __icheckuser (user, ruser);
 674
 675             /* Positive 'host user' match? */
 676             if (ucheck > 0) {
 677                 retval = 0;
 678                 break;
 679             }
 680
 681             /* Negative 'host -user' match? */
 682             if (ucheck < 0)
 683                 break;
 684
 685             /* Neither, go on looking for match */
 686         }
 687     }
 688
 689     free (buf);
 690
 691     return retval;
 692 }