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 <alloca.h>
  73 #include <signal.h>
  74 #include <fcntl.h>
  75 #include <netdb.h>
  76 #include <unistd.h>
  77 #include <pwd.h>
  78 #include <errno.h>
  79 #include <stdio.h>
  80 #include <stdio_ext.h>
  81 #include <ctype.h>
  82 #include <string.h>
  83 #include <libintl.h>
  84 #include <stdlib.h>
  85 #ifdef __UCLIBC_HAS_WCHAR__
  86 #include <wchar.h>
  87 #endif
  88 #include <sys/uio.h>
  89
  90
  91 /* some forward declarations */
  92 static int __ivaliduser2(FILE *hostf, u_int32_t raddr,
  93                          const char *luser, const char *ruser, const char *rhost);
  94 static int iruserok2 (u_int32_t raddr, int superuser, const char *ruser,
  95                       const char *luser, const char *rhost);
  96
  97
  98 int rcmd(ahost, rport, locuser, remuser, cmd, fd2p)
  99      char **ahost;
 100      u_short rport;
 101      const char *locuser, *remuser, *cmd;
 102      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 #ifdef __ARCH_USE_MMU__
 123         tmphstbuf = alloca (hstbuflen);
 124 #else
 125         tmphstbuf = malloc (hstbuflen);
 126 #endif
 127
 128         while (gethostbyname_r (*ahost, &hostbuf, tmphstbuf,
 129                     hstbuflen, &hp, &herr) != 0 || hp == NULL)
 130         {
 131             if (herr != NETDB_INTERNAL || errno != ERANGE)
 132             {
 133                 __set_h_errno (herr);
 134 #ifndef __ARCH_USE_MMU__
 135                 free(tmphstbuf);
 136 #endif
 137                 herror(*ahost);
 138                 return -1;
 139             }
 140             else
 141             {
 142                 /* Enlarge the buffer.  */
 143                 hstbuflen *= 2;
 144 #ifdef __ARCH_USE_MMU__
 145                 tmphstbuf = alloca (hstbuflen);
 146 #else
 147                 free(tmphstbuf);
 148                 tmphstbuf = malloc (hstbuflen);
 149 #endif
 150             }
 151         }
 152 #ifndef __ARCH_USE_MMU__
 153         free(tmphstbuf);
 154 #endif
 155 #else /* call the non-reentrant version */
 156         if ((hp = gethostbyname(*ahost)) == NULL) {
 157             return -1;
 158         }
 159 #endif
 160         pfd[0].events = POLLIN;
 161         pfd[1].events = POLLIN;
 162
 163         *ahost = hp->h_name;
 164         oldmask = sigblock(sigmask(SIGURG)); /* __sigblock */
 165         for (timo = 1, lport = IPPORT_RESERVED - 1;;) {
 166                 s = rresvport(&lport);
 167                 if (s < 0) {
 168                         if (errno == EAGAIN)
 169                             (void)fprintf(stderr,
 170                                           "rcmd: socket: All ports in use\n");
 171                         else
 172                             (void)fprintf(stderr, "rcmd: socket: %m\n");
 173                         sigsetmask(oldmask); /* sigsetmask */
 174                         return -1;
 175                 }
 176                 fcntl(s, F_SETOWN, pid);
 177                 sin.sin_family = hp->h_addrtype;
 178                 memmove(&sin.sin_addr, hp->h_addr_list[0],
 179                       MIN (sizeof (sin.sin_addr), hp->h_length));
 180                 sin.sin_port = rport;
 181                 if (connect(s, (struct sockaddr *)&sin, sizeof(sin)) >= 0) /* __connect */
 182                         break;
 183                 (void)close(s);
 184                 if (errno == EADDRINUSE) {
 185                         lport--;
 186                         continue;
 187                 }
 188                 if (errno == ECONNREFUSED && timo <= 16) {
 189                         (void)sleep(timo); /* __sleep */
 190                         timo *= 2;
 191                         continue;
 192                 }
 193                 if (hp->h_addr_list[1] != NULL) {
 194                         int oerrno = errno;
 195
 196                         (void)fprintf(stderr, "connect to address %s: ",
 197                             inet_ntoa(sin.sin_addr));
 198                         __set_errno (oerrno);
 199                         perror(0);
 200                         hp->h_addr_list++;
 201                         memmove(&sin.sin_addr, hp->h_addr_list[0],
 202                               MIN (sizeof (sin.sin_addr), hp->h_length));
 203                         (void)fprintf(stderr, "Trying %s...\n",
 204                             inet_ntoa(sin.sin_addr));
 205                         continue;
 206                 }
 207                 (void)fprintf(stderr, "%s: %m\n", hp->h_name);
 208                 sigsetmask(oldmask); /* __sigsetmask */
 209                 return -1;
 210         }
 211         lport--;
 212         if (fd2p == 0) {
 213                 write(s, "", 1);
 214                 lport = 0;
 215         } else {
 216                 char num[8];
 217                 int s2 = rresvport(&lport), s3;
 218                 socklen_t len = sizeof(from);
 219
 220                 if (s2 < 0)
 221                         goto bad;
 222                 listen(s2, 1);
 223                 (void)snprintf(num, sizeof(num), "%d", lport); /* __snprintf */
 224                 if (write(s, num, strlen(num)+1) != strlen(num)+1) {
 225                         (void)fprintf(stderr,
 226                                       "rcmd: write (setting up stderr): %m\n");
 227                         (void)close(s2);
 228                         goto bad;
 229                 }
 230                 pfd[0].fd = s;
 231                 pfd[1].fd = s2;
 232                 __set_errno (0);
 233                 if (poll (pfd, 2, -1) < 1 || (pfd[1].revents & POLLIN) == 0){
 234                     if (errno != 0)
 235                         (void)fprintf(stderr, "rcmd: poll (setting up stderr): %m\n");
 236                     else
 237                         (void)fprintf(stderr, "poll: protocol failure in circuit setup\n");
 238                         (void)close(s2);
 239                         goto bad;
 240                 }
 241                 s3 = accept(s2, (struct sockaddr *)&from, &len);
 242                 (void)close(s2);
 243                 if (s3 < 0) {
 244                         (void)fprintf(stderr,
 245                             "rcmd: accept: %m\n");
 246                         lport = 0;
 247                         goto bad;
 248                 }
 249                 *fd2p = s3;
 250                 from.sin_port = ntohs((u_short)from.sin_port);
 251                 if (from.sin_family != AF_INET ||
 252                     from.sin_port >= IPPORT_RESERVED ||
 253                     from.sin_port < IPPORT_RESERVED / 2) {
 254                         (void)fprintf(stderr,
 255                             "socket: protocol failure in circuit setup\n");
 256                         goto bad2;
 257                 }
 258         }
 259         (void)write(s, locuser, strlen(locuser)+1);
 260         (void)write(s, remuser, strlen(remuser)+1);
 261         (void)write(s, cmd, strlen(cmd)+1);
 262         if (read(s, &c, 1) != 1) {
 263                 (void)fprintf(stderr,
 264                     "rcmd: %s: %m\n", *ahost);
 265                 goto bad2;
 266         }
 267         if (c != 0) {
 268                 while (read(s, &c, 1) == 1) {
 269                         (void)write(STDERR_FILENO, &c, 1);
 270                         if (c == '\n')
 271                                 break;
 272                 }
 273                 goto bad2;
 274         }
 275         sigsetmask(oldmask);
 276         return s;
 277 bad2:
 278         if (lport)
 279                 (void)close(*fd2p);
 280 bad:
 281         (void)close(s);
 282         sigsetmask(oldmask);
 283         return -1;
 284 }
 285
 286 int rresvport(int *alport)
 287 {
 288     struct sockaddr_in sin;
 289     int s;
 290
 291     sin.sin_family = AF_INET;
 292     sin.sin_addr.s_addr = INADDR_ANY;
 293     s = socket(AF_INET, SOCK_STREAM, 0);
 294     if (s < 0)
 295         return -1;
 296     for (;;) {
 297         sin.sin_port = htons((u_short)*alport);
 298         if (bind(s, (struct sockaddr *)&sin, sizeof(sin)) >= 0)
 299             return s;
 300         if (errno != EADDRINUSE) {
 301             (void)close(s);
 302             return -1;
 303         }
 304         (*alport)--;
 305         if (*alport == IPPORT_RESERVED/2) {
 306             (void)close(s);
 307             __set_errno (EAGAIN);               /* close */
 308             return -1;
 309         }
 310     }
 311
 312     return -1;
 313 }
 314 libc_hidden_def(rresvport)
 315
 316 /* This needs to be exported ... while it is not a documented interface
 317  * for rcp related apps, it's a required one that is used to control the
 318  * rhost behavior.  Legacy sucks.
 319  */
 320 int  __check_rhosts_file = 1;
 321
 322 int ruserok(rhost, superuser, ruser, luser)
 323         const char *rhost, *ruser, *luser;
 324         int superuser;
 325 {
 326         struct hostent *hp;
 327         u_int32_t addr;
 328         char **ap;
 329 #ifdef __UCLIBC_HAS_REENTRANT_RPC__
 330         size_t buflen;
 331         char *buffer;
 332         int herr;
 333         struct hostent hostbuf;
 334 #endif
 335
 336 #ifdef __UCLIBC_HAS_REENTRANT_RPC__
 337         buflen = 1024;
 338 #ifdef __ARCH_USE_MMU__
 339         buffer = alloca (buflen);
 340 #else
 341         buffer = malloc (buflen);
 342 #endif
 343
 344         while (gethostbyname_r (rhost, &hostbuf, buffer,
 345                     buflen, &hp, &herr) != 0 || hp == NULL)
 346         {
 347             if (herr != NETDB_INTERNAL || errno != ERANGE) {
 348 #ifndef __ARCH_USE_MMU__
 349                 free(buffer);
 350 #endif
 351                 return -1;
 352             } else
 353             {
 354                 /* Enlarge the buffer.  */
 355                 buflen *= 2;
 356 #ifdef __ARCH_USE_MMU__
 357                 buffer = alloca (buflen);
 358 #else
 359                 free(buffer);
 360                 buffer = malloc (buflen);
 361 #endif
 362             }
 363         }
 364 #ifndef __ARCH_USE_MMU__
 365         free(buffer);
 366 #endif
 367 #else
 368         if ((hp = gethostbyname(rhost)) == NULL) {
 369                 return -1;
 370         }
 371 #endif
 372         for (ap = hp->h_addr_list; *ap; ++ap) {
 373                 memmove(&addr, *ap, sizeof(addr));
 374                 if (iruserok2(addr, superuser, ruser, luser, rhost) == 0)
 375                         return 0;
 376         }
 377         return -1;
 378 }
 379
 380
 381 /* Extremely paranoid file open function. */
 382 static FILE *
 383 iruserfopen (const char *file, uid_t okuser)
 384 {
 385   struct stat st;
 386   char *cp = NULL;
 387   FILE *res = NULL;
 388
 389   /* If not a regular file, if owned by someone other than user or
 390      root, if writeable by anyone but the owner, or if hardlinked
 391      anywhere, quit.  */
 392   if (lstat (file, &st))
 393     cp = "lstat failed";
 394   else if (!S_ISREG (st.st_mode))
 395     cp = "not regular file";
 396   else
 397     {
 398       res = fopen (file, "r");
 399       if (!res)
 400         cp = "cannot open";
 401       else if (fstat (fileno (res), &st) < 0)
 402         cp = "fstat failed";
 403       else if (st.st_uid && st.st_uid != okuser)
 404         cp = "bad owner";
 405       else if (st.st_mode & (S_IWGRP|S_IWOTH))
 406         cp = "writeable by other than owner";
 407       else if (st.st_nlink > 1)
 408         cp = "hard linked somewhere";
 409     }
 410
 411   /* If there were any problems, quit.  */
 412   if (cp != NULL)
 413     {
 414       if (res)
 415         fclose (res);
 416       return NULL;
 417     }
 418
 419   return res;
 420 }
 421
 422
 423 /*
 424  * New .rhosts strategy: We are passed an ip address. We spin through
 425  * hosts.equiv and .rhosts looking for a match. When the .rhosts only
 426  * has ip addresses, we don't have to trust a nameserver.  When it
 427  * contains hostnames, we spin through the list of addresses the nameserver
 428  * gives us and look for a match.
 429  *
 430  * Returns 0 if ok, -1 if not ok.
 431  */
 432 static int
 433 iruserok2 (raddr, superuser, ruser, luser, rhost)
 434      u_int32_t raddr;
 435      int superuser;
 436      const char *ruser, *luser, *rhost;
 437 {
 438         FILE *hostf = NULL;
 439         int isbad = -1;
 440
 441         if (!superuser)
 442                 hostf = iruserfopen (_PATH_HEQUIV, 0);
 443
 444         if (hostf) {
 445                 isbad = __ivaliduser2 (hostf, raddr, luser, ruser, rhost);
 446                 fclose (hostf);
 447
 448                 if (!isbad)
 449                         return 0;
 450         }
 451
 452         if (__check_rhosts_file || superuser) {
 453                 char *pbuf;
 454                 struct passwd *pwd;
 455                 size_t dirlen;
 456                 uid_t uid;
 457
 458 #ifdef __UCLIBC_HAS_REENTRANT_RPC__
 459                 size_t buflen = sysconf (_SC_GETPW_R_SIZE_MAX);
 460                 struct passwd pwdbuf;
 461 #ifdef __ARCH_USE_MMU__
 462                 char *buffer = alloca (buflen);
 463 #else
 464                 char *buffer = malloc (buflen);
 465 #endif
 466
 467                 if (getpwnam_r (luser, &pwdbuf, buffer,
 468                             buflen, &pwd) != 0 || pwd == NULL)
 469                 {
 470 #ifndef __ARCH_USE_MMU__
 471                         free(buffer);
 472 #endif
 473                         return -1;
 474                 }
 475 #ifndef __ARCH_USE_MMU__
 476                 free(buffer);
 477 #endif
 478 #else
 479                 if ((pwd = getpwnam(luser)) == NULL)
 480                         return -1;
 481 #endif
 482
 483                 dirlen = strlen (pwd->pw_dir);
 484                 pbuf = malloc (dirlen + sizeof "/.rhosts");
 485                 strcpy (pbuf, pwd->pw_dir);
 486                 strcat (pbuf, "/.rhosts");
 487
 488                 /* Change effective uid while reading .rhosts.  If root and
 489                    reading an NFS mounted file system, can't read files that
 490                    are protected read/write owner only.  */
 491                 uid = geteuid ();
 492                 seteuid (pwd->pw_uid);
 493                 hostf = iruserfopen (pbuf, pwd->pw_uid);
 494                 free(pbuf);
 495
 496                 if (hostf != NULL) {
 497                         isbad = __ivaliduser2 (hostf, raddr, luser, ruser, rhost);
 498                         fclose (hostf);
 499                 }
 500
 501                 seteuid (uid);
 502                 return isbad;
 503         }
 504         return -1;
 505 }
 506
 507 /* This is the exported version.  */
 508 int iruserok (u_int32_t raddr, int superuser, const char * ruser, const char * luser);
 509 int iruserok (u_int32_t raddr, int superuser, const char * ruser, const char * luser)
 510 {
 511         return iruserok2 (raddr, superuser, ruser, luser, "-");
 512 }
 513
 514
 515 /*
 516  * XXX
 517  * Don't make static, used by lpd(8).
 518  *
 519  * This function is not used anymore. It is only present because lpd(8)
 520  * calls it (!?!). We simply call __invaliduser2() with an illegal rhost
 521  * argument. This means that netgroups won't work in .rhost/hosts.equiv
 522  * files. If you want lpd to work with netgroups, fix lpd to use ruserok()
 523  * or PAM.
 524  * Returns 0 if ok, -1 if not ok.
 525  */
 526 int
 527 __ivaliduser(FILE *hostf, u_int32_t raddr, const char *luser, const char *ruser);
 528 int
 529 __ivaliduser(FILE *hostf, u_int32_t raddr, const char *luser, const char *ruser)
 530 {
 531         return __ivaliduser2(hostf, raddr, luser, ruser, "-");
 532 }
 533
 534
 535 /* Returns 1 on positive match, 0 on no match, -1 on negative match.  */
 536 static int
 537 __icheckhost (u_int32_t raddr, char *lhost, const char *rhost)
 538 {
 539         struct hostent *hp;
 540         u_int32_t laddr;
 541         int negate=1;    /* Multiply return with this to get -1 instead of 1 */
 542         char **pp;
 543
 544 #ifdef __UCLIBC_HAS_REENTRANT_RPC__
 545         int save_errno;
 546         size_t buflen;
 547         char *buffer;
 548         struct hostent hostbuf;
 549         int herr;
 550 #endif
 551
 552 #ifdef HAVE_NETGROUP
 553         /* Check nis netgroup.  */
 554         if (strncmp ("+@", lhost, 2) == 0)
 555                 return innetgr (&lhost[2], rhost, NULL, NULL);
 556
 557         if (strncmp ("-@", lhost, 2) == 0)
 558                 return -innetgr (&lhost[2], rhost, NULL, NULL);
 559 #endif /* HAVE_NETGROUP */
 560
 561         /* -host */
 562         if (strncmp ("-", lhost,1) == 0) {
 563                 negate = -1;
 564                 lhost++;
 565         } else if (strcmp ("+",lhost) == 0) {
 566                 return 1;                    /* asking for trouble, but ok.. */
 567         }
 568
 569         /* Try for raw ip address first. */
 570         if (isdigit (*lhost) && (laddr = inet_addr (lhost)) != INADDR_NONE)
 571                 return negate * (! (raddr ^ laddr));
 572
 573         /* Better be a hostname. */
 574 #ifdef __UCLIBC_HAS_REENTRANT_RPC__
 575         buflen = 1024;
 576         buffer = malloc(buflen);
 577         save_errno = errno;
 578
 579         while (gethostbyname_r (lhost, &hostbuf, buffer, buflen, &hp, &herr)
 580                != 0) {
 581             free(buffer);
 582             return (0);
 583         }
 584         free(buffer);
 585         __set_errno (save_errno);
 586 #else
 587         hp = gethostbyname(lhost);
 588 #endif /* __UCLIBC_HAS_REENTRANT_RPC__ */
 589
 590         if (hp == NULL)
 591                 return 0;
 592
 593         /* Spin through ip addresses. */
 594         for (pp = hp->h_addr_list; *pp; ++pp)
 595                 if (!memcmp (&raddr, *pp, sizeof (u_int32_t)))
 596                         return negate;
 597
 598         /* No match. */
 599         return (0);
 600 }
 601
 602 /* Returns 1 on positive match, 0 on no match, -1 on negative match.  */
 603 static int
 604 __icheckuser (const char *luser, const char *ruser)
 605 {
 606
 607     /*
 608       luser is user entry from .rhosts/hosts.equiv file
 609       ruser is user id on remote host
 610       */
 611
 612 #ifdef HAVE_NETGROUP
 613     /* [-+]@netgroup */
 614     if (strncmp ("+@", luser, 2) == 0)
 615         return innetgr (&luser[2], NULL, ruser, NULL);
 616
 617     if (strncmp ("-@", luser,2) == 0)
 618         return -innetgr (&luser[2], NULL, ruser, NULL);
 619 #endif /* HAVE_NETGROUP */
 620
 621     /* -user */
 622     if (strncmp ("-", luser, 1) == 0)
 623         return -(strcmp (&luser[1], ruser) == 0);
 624
 625     /* + */
 626     if (strcmp ("+", luser) == 0)
 627         return 1;
 628
 629     /* simple string match */
 630     return strcmp (ruser, luser) == 0;
 631 }
 632
 633 /*
 634  * Returns 1 for blank lines (or only comment lines) and 0 otherwise
 635  */
 636 static int
 637 __isempty(char *p)
 638 {
 639     while (*p && isspace (*p)) {
 640         ++p;
 641     }
 642
 643     return (*p == '\0' || *p == '#') ? 1 : 0 ;
 644 }
 645
 646 /*
 647  * Returns 0 if positive match, -1 if _not_ ok.
 648  */
 649 static int
 650 __ivaliduser2(hostf, raddr, luser, ruser, rhost)
 651         FILE *hostf;
 652         u_int32_t raddr;
 653         const char *luser, *ruser, *rhost;
 654 {
 655     register const char *user;
 656     register char *p;
 657     int hcheck, ucheck;
 658     char *buf = NULL;
 659     size_t bufsize = 0;
 660     int retval = -1;
 661
 662     while (getline (&buf, &bufsize, hostf) > 0) {
 663         buf[bufsize - 1] = '\0'; /* Make sure it's terminated.  */
 664         p = buf;
 665
 666         /* Skip empty or comment lines */
 667         if (__isempty (p)) {
 668             continue;
 669         }
 670
 671         /* Skip lines that are too long. */
 672         if (strchr (p, '\n') == NULL) {
 673             int ch = getc_unlocked (hostf);
 674
 675             while (ch != '\n' && ch != EOF)
 676               ch = getc_unlocked (hostf);
 677             continue;
 678         }
 679
 680         for (;*p && !isspace(*p); ++p) {
 681             *p = tolower (*p);
 682         }
 683
 684         /* Next we want to find the permitted name for the remote user.  */
 685         if (*p == ' ' || *p == '\t') {
 686             /* <nul> terminate hostname and skip spaces */
 687             for (*p++='\0'; *p && isspace (*p); ++p);
 688
 689             user = p;                   /* this is the user's name */
 690             while (*p && !isspace (*p))
 691                 ++p;                    /* find end of user's name */
 692         } else
 693             user = p;
 694
 695         *p = '\0';              /* <nul> terminate username (+host?) */
 696
 697         /* buf -> host(?) ; user -> username(?) */
 698
 699         /* First check host part */
 700         hcheck = __icheckhost (raddr, buf, rhost);
 701
 702         if (hcheck < 0)
 703             break;
 704
 705         if (hcheck) {
 706             /* Then check user part */
 707             if (! (*user))
 708                 user = luser;
 709
 710             ucheck = __icheckuser (user, ruser);
 711
 712             /* Positive 'host user' match? */
 713             if (ucheck > 0) {
 714                 retval = 0;
 715                 break;
 716             }
 717
 718             /* Negative 'host -user' match? */
 719             if (ucheck < 0)
 720                 break;
 721
 722             /* Neither, go on looking for match */
 723         }
 724     }
 725
 726     free (buf);
 727
 728     return retval;
 729 }