util.subproj/rcmd.c

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Portions Copyright (c) 1999 Apple Computer, Inc.  All Rights
   7  * Reserved.  This file contains Original Code and/or Modifications of
   8  * Original Code as defined in and that are subject to the Apple Public
   9  * Source License Version 1.1 (the "License").  You may not use this file
  10  * except in compliance with the License.  Please obtain a copy of the
  11  * License at http://www.apple.com/publicsource and read it before using
  12  * this file.
  13  *
  14  * The Original Code and all software distributed under the License are
  15  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  16  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  17  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE OR NON- INFRINGEMENT.  Please see the
  19  * License for the specific language governing rights and limitations
  20  * under the License.
  21  *
  22  * @APPLE_LICENSE_HEADER_END@
  23  */
  24 /*
  25  * Copyright (c) 1995, 1996, 1998 Theo de Raadt.  All rights reserved.
  26  * Copyright (c) 1983, 1993, 1994
  27  *      The Regents of the University of California.  All rights reserved.
  28  *
  29  * Redistribution and use in source and binary forms, with or without
  30  * modification, are permitted provided that the following conditions
  31  * are met:
  32  * 1. Redistributions of source code must retain the above copyright
  33  *    notice, this list of conditions and the following disclaimer.
  34  * 2. Redistributions in binary form must reproduce the above copyright
  35  *    notice, this list of conditions and the following disclaimer in the
  36  *    documentation and/or other materials provided with the distribution.
  37  * 3. All advertising materials mentioning features or use of this software
  38  *    must display the following acknowledgement:
  39  *      This product includes software developed by the University of
  40  *      California, Berkeley and its contributors.
  41  *      This product includes software developed by Theo de Raadt.
  42  * 4. Neither the name of the University nor the names of its contributors
  43  *    may be used to endorse or promote products derived from this software
  44  *    without specific prior written permission.
  45  *
  46  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  47  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  48  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  49  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  50  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  51  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  52  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  53  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  54  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  55  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  56  * SUCH DAMAGE.
  57  *
  58  * $FreeBSD: src/lib/libc/net/rcmd.c,v 1.23.2.5 2001/03/05 10:47:11 obrien Exp $
  59  */
  60
  61 #if defined(LIBC_SCCS) && !defined(lint)
  62 static char sccsid[] = "@(#)rcmd.c      8.3 (Berkeley) 3/26/94";
  63 #endif /* LIBC_SCCS and not lint */
  64
  65 #include <sys/param.h>
  66 #include <sys/socket.h>
  67 #include <sys/stat.h>
  68
  69 #include <netinet/in.h>
  70 #include <arpa/inet.h>
  71 #include <netinfo/ni_util.h>
  72
  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 <ctype.h>
  81 #include <string.h>
  82 #ifdef YP
  83 #include <rpc/rpc.h>
  84 #include <rpcsvc/yp_prot.h>
  85 #include <rpcsvc/ypclnt.h>
  86 #endif
  87 #include <arpa/nameser.h>
  88
  89 /* wrapper for KAME-special getnameinfo() */
  90 #ifndef NI_WITHSCOPEID
  91 #define NI_WITHSCOPEID  0
  92 #endif
  93
  94 #ifndef socklen_t
  95 #define socklen_t int
  96 #endif
  97
  98 extern int innetgr __P(( const char *, const char *, const char *, const char * ));
  99
 100 #define max(a, b)       ((a > b) ? a : b)
 101
 102 int     __ivaliduser __P((FILE *, u_int32_t, const char *, const char *));
 103 int __ivaliduser_af __P((FILE *,const void *, const char *, const char *,
 104         int, int));
 105 int __ivaliduser_sa __P((FILE *, const struct sockaddr *, socklen_t,
 106         const char *,const char *));
 107 static int __icheckhost __P((const struct sockaddr *, socklen_t,
 108         const char *));
 109
 110
 111 int
 112 rcmd(ahost, rport, locuser, remuser, cmd, fd2p)
 113         char **ahost;
 114         in_port_t rport;
 115         const char *locuser, *remuser, *cmd;
 116         int *fd2p;
 117 {
 118         return rcmd_af(ahost, rport, locuser, remuser, cmd, fd2p, AF_INET);
 119 }
 120
 121 int
 122 rcmd_af(ahost, rport, locuser, remuser, cmd, fd2p, af)
 123         char **ahost;
 124         u_short rport;
 125         const char *locuser, *remuser, *cmd;
 126         int *fd2p;
 127         int af;
 128 {
 129         struct addrinfo hints, *res, *ai;
 130         struct sockaddr_storage from;
 131         fd_set reads;
 132         long oldmask;
 133         pid_t pid;
 134         int s, aport, lport, timo, error;
 135         char c;
 136         int refused, nres;
 137         char num[8], paddr[NI_MAXHOST];
 138         static char canonnamebuf[MAXDNAME];     /* is it proper here? */
 139
 140         pid = getpid();
 141
 142         memset(&hints, 0, sizeof(hints));
 143         hints.ai_flags = AI_CANONNAME;
 144         hints.ai_family = af;
 145         hints.ai_socktype = SOCK_STREAM;
 146         hints.ai_protocol = 0;
 147         (void)snprintf(num, sizeof(num), "%d", ntohs(rport));
 148         error = getaddrinfo(*ahost, num, &hints, &res);
 149         if (error) {
 150                 fprintf(stderr, "rcmd: getaddrinfo: %s\n",
 151                         gai_strerror(error));
 152                 if (error == EAI_SYSTEM)
 153                         fprintf(stderr, "rcmd: getaddrinfo: %s\n",
 154                                 strerror(errno));
 155                 return (-1);
 156         }
 157
 158         if (res->ai_canonname
 159          && strlen(res->ai_canonname) + 1 < sizeof(canonnamebuf)) {
 160                 strncpy(canonnamebuf, res->ai_canonname, sizeof(canonnamebuf));
 161                 *ahost = canonnamebuf;
 162         }
 163         nres = 0;
 164         for (ai = res; ai; ai = ai->ai_next)
 165                 nres++;
 166         ai = res;
 167         refused = 0;
 168         oldmask = sigblock(sigmask(SIGURG));
 169         for (timo = 1, lport = IPPORT_RESERVED - 1;;) {
 170                 s = rresvport_af(&lport, ai->ai_family);
 171                 if (s < 0) {
 172                         if (errno != EAGAIN && ai->ai_next) {
 173                                 ai = ai->ai_next;
 174                                 continue;
 175                         }
 176                         if (errno == EAGAIN)
 177                                 (void)fprintf(stderr,
 178                                     "rcmd: socket: All ports in use\n");
 179                         else
 180                                 (void)fprintf(stderr, "rcmd: socket: %s\n",
 181                                     strerror(errno));
 182                         freeaddrinfo(res);
 183                         sigsetmask(oldmask);
 184                         return (-1);
 185                 }
 186                 fcntl(s, F_SETOWN, pid);
 187                 if (connect(s, ai->ai_addr, ai->ai_addrlen) >= 0)
 188                         break;
 189                 (void)close(s);
 190                 if (errno == EADDRINUSE) {
 191                         lport--;
 192                         continue;
 193                 }
 194                 if (errno == ECONNREFUSED)
 195                         refused = 1;
 196                 if (ai->ai_next == NULL && (!refused || timo > 16)) {
 197                         (void)fprintf(stderr, "%s: %s\n",
 198                                       *ahost, strerror(errno));
 199                         freeaddrinfo(res);
 200                         sigsetmask(oldmask);
 201                         return (-1);
 202                 }
 203                 if (nres > 1) {
 204                         int oerrno = errno;
 205
 206                         getnameinfo(ai->ai_addr, ai->ai_addrlen,
 207                                     paddr, sizeof(paddr),
 208                                     NULL, 0,
 209                                     NI_NUMERICHOST|NI_WITHSCOPEID);
 210                         (void)fprintf(stderr, "connect to address %s: ",
 211                                       paddr);
 212                         errno = oerrno;
 213                         perror(0);
 214                 }
 215                 if ((ai = ai->ai_next) == NULL) {
 216                         /* refused && timo <= 16 */
 217                         struct timespec time_to_sleep, time_remaining;
 218
 219                         time_to_sleep.tv_sec = timo;
 220                         time_to_sleep.tv_nsec = 0;
 221                         (void)nanosleep(&time_to_sleep, &time_remaining);
 222                         timo *= 2;
 223                         ai = res;
 224                         refused = 0;
 225                 }
 226                 if (nres > 1) {
 227                         getnameinfo(ai->ai_addr, ai->ai_addrlen,
 228                                     paddr, sizeof(paddr),
 229                                     NULL, 0,
 230                                     NI_NUMERICHOST|NI_WITHSCOPEID);
 231                         fprintf(stderr, "Trying %s...\n", paddr);
 232                 }
 233         }
 234 #if 0
 235         /*
 236          * try to rresvport() to the same port. This will make rresvport()
 237          * fail it's first bind, resulting in it choosing a random port.
 238          */
 239         lport--;
 240 #endif
 241         if (fd2p == 0) {
 242                 write(s, "", 1);
 243                 lport = 0;
 244         } else {
 245                 char num[8];
 246                 int s2 = rresvport_af(&lport, ai->ai_family), s3;
 247                 int len = ai->ai_addrlen;
 248                 int nfds;
 249
 250                 if (s2 < 0)
 251                         goto bad;
 252                 listen(s2, 1);
 253                 (void)snprintf(num, sizeof(num), "%d", lport);
 254                 if (write(s, num, strlen(num)+1) != strlen(num)+1) {
 255                         (void)fprintf(stderr,
 256                             "rcmd: write (setting up stderr): %s\n",
 257                             strerror(errno));
 258                         (void)close(s2);
 259                         goto bad;
 260                 }
 261                 nfds = max(s, s2)+1;
 262                 if(nfds > FD_SETSIZE) {
 263                         fprintf(stderr, "rcmd: too many files\n");
 264                         (void)close(s2);
 265                         goto bad;
 266                 }
 267 again:
 268                 FD_ZERO(&reads);
 269                 FD_SET(s, &reads);
 270                 FD_SET(s2, &reads);
 271                 errno = 0;
 272                 if (select(nfds, &reads, 0, 0, 0) < 1 || !FD_ISSET(s2, &reads)){
 273                         if (errno != 0)
 274                                 (void)fprintf(stderr,
 275                                     "rcmd: select (setting up stderr): %s\n",
 276                                     strerror(errno));
 277                         else
 278                                 (void)fprintf(stderr,
 279                                 "select: protocol failure in circuit setup\n");
 280                         (void)close(s2);
 281                         goto bad;
 282                 }
 283                 s3 = accept(s2, (struct sockaddr *)&from, &len);
 284                 switch (from.ss_family) {
 285                 case AF_INET:
 286                         aport = ntohs(((struct sockaddr_in *)&from)->sin_port);
 287                         break;
 288 #ifdef INET6
 289                 case AF_INET6:
 290                         aport = ntohs(((struct sockaddr_in6 *)&from)->sin6_port);
 291                         break;
 292 #endif
 293                 default:
 294                         aport = 0;      /* error */
 295                         break;
 296                 }
 297                 /*
 298                  * XXX careful for ftp bounce attacks. If discovered, shut them
 299                  * down and check for the real auxiliary channel to connect.
 300                  */
 301                 if (aport == 20) {
 302                         close(s3);
 303                         goto again;
 304                 }
 305                 (void)close(s2);
 306                 if (s3 < 0) {
 307                         (void)fprintf(stderr,
 308                             "rcmd: accept: %s\n", strerror(errno));
 309                         lport = 0;
 310                         goto bad;
 311                 }
 312                 *fd2p = s3;
 313                 if (aport >= IPPORT_RESERVED || aport < IPPORT_RESERVED / 2) {
 314                         (void)fprintf(stderr,
 315                             "socket: protocol failure in circuit setup.\n");
 316                         goto bad2;
 317                 }
 318         }
 319         (void)write(s, locuser, strlen(locuser)+1);
 320         (void)write(s, remuser, strlen(remuser)+1);
 321         (void)write(s, cmd, strlen(cmd)+1);
 322         if (read(s, &c, 1) != 1) {
 323                 (void)fprintf(stderr,
 324                     "rcmd: %s: %s\n", *ahost, strerror(errno));
 325                 goto bad2;
 326         }
 327         if (c != 0) {
 328                 while (read(s, &c, 1) == 1) {
 329                         (void)write(STDERR_FILENO, &c, 1);
 330                         if (c == '\n')
 331                                 break;
 332                 }
 333                 goto bad2;
 334         }
 335         sigsetmask(oldmask);
 336         freeaddrinfo(res);
 337         return (s);
 338 bad2:
 339         if (lport)
 340                 (void)close(*fd2p);
 341 bad:
 342         (void)close(s);
 343         sigsetmask(oldmask);
 344         freeaddrinfo(res);
 345         return (-1);
 346 }
 347
 348 int
 349 rresvport(port)
 350         int *port;
 351 {
 352         return rresvport_af(port, AF_INET);
 353 }
 354
 355 int
 356 rresvport_af(alport, family)
 357         int *alport, family;
 358 {
 359         int s;
 360         struct sockaddr_storage ss;
 361         u_short *sport;
 362
 363         memset(&ss, 0, sizeof(ss));
 364         ss.ss_family = family;
 365         switch (family) {
 366         case AF_INET:
 367                 ((struct sockaddr *)&ss)->sa_len = sizeof(struct sockaddr_in);
 368                 sport = &((struct sockaddr_in *)&ss)->sin_port;
 369                 ((struct sockaddr_in *)&ss)->sin_addr.s_addr = INADDR_ANY;
 370                 break;
 371 #ifdef INET6
 372         case AF_INET6:
 373                 ((struct sockaddr *)&ss)->sa_len = sizeof(struct sockaddr_in6);
 374                 sport = &((struct sockaddr_in6 *)&ss)->sin6_port;
 375                 ((struct sockaddr_in6 *)&ss)->sin6_addr = in6addr_any;
 376                 break;
 377 #endif
 378         default:
 379                 errno = EAFNOSUPPORT;
 380                 return -1;
 381         }
 382
 383         s = socket(ss.ss_family, SOCK_STREAM, 0);
 384         if (s < 0)
 385                 return (-1);
 386 #if 0 /* compat_exact_traditional_rresvport_semantics */
 387         sin.sin_port = htons((u_short)*alport);
 388         if (bind(s, (struct sockaddr *)&sin, sizeof(sin)) >= 0)
 389                 return (s);
 390         if (errno != EADDRINUSE) {
 391                 (void)close(s);
 392                 return (-1);
 393         }
 394 #endif
 395         *sport = 0;
 396         if (bindresvport_sa(s, (struct sockaddr *)&ss) == -1) {
 397                 (void)close(s);
 398                 return (-1);
 399         }
 400         *alport = (int)ntohs(*sport);
 401         return (s);
 402 }
 403
 404 int     __check_rhosts_file = 1;
 405 char    *__rcmd_errstr;
 406
 407 int
 408 ruserok(rhost, superuser, ruser, luser)
 409         const char *rhost, *ruser, *luser;
 410         int superuser;
 411 {
 412         struct addrinfo hints, *res, *r;
 413         int error;
 414
 415         memset(&hints, 0, sizeof(hints));
 416         hints.ai_family = PF_UNSPEC;
 417         hints.ai_socktype = SOCK_DGRAM; /*dummy*/
 418         error = getaddrinfo(rhost, "0", &hints, &res);
 419         if (error)
 420                 return (-1);
 421
 422         for (r = res; r; r = r->ai_next) {
 423                 if (iruserok_sa(r->ai_addr, r->ai_addrlen, superuser, ruser,
 424                     luser) == 0) {
 425                         freeaddrinfo(res);
 426                         return (0);
 427                 }
 428         }
 429         freeaddrinfo(res);
 430         return (-1);
 431 }
 432
 433 /*
 434  * New .rhosts strategy: We are passed an ip address. We spin through
 435  * hosts.equiv and .rhosts looking for a match. When the .rhosts only
 436  * has ip addresses, we don't have to trust a nameserver.  When it
 437  * contains hostnames, we spin through the list of addresses the nameserver
 438  * gives us and look for a match.
 439  *
 440  * Returns 0 if ok, -1 if not ok.
 441  */
 442 int
 443 iruserok(raddr, superuser, ruser, luser)
 444         unsigned long raddr;
 445         int superuser;
 446         const char *ruser, *luser;
 447 {
 448         struct sockaddr_in sin;
 449
 450         memset(&sin, 0, sizeof(sin));
 451         sin.sin_family = AF_INET;
 452         sin.sin_len = sizeof(struct sockaddr_in);
 453         memcpy(&sin.sin_addr, &raddr, sizeof(sin.sin_addr));
 454         return iruserok_sa((struct sockaddr *)&sin, sin.sin_len, superuser,
 455                 ruser, luser);
 456 }
 457
 458 /*
 459  * AF independent extension of iruserok.
 460  *
 461  * Returns 0 if ok, -1 if not ok.
 462  */
 463 int
 464 iruserok_sa(ra, rlen, superuser, ruser, luser)
 465         const void *ra;
 466         int rlen;
 467         int superuser;
 468         const char *ruser, *luser;
 469 {
 470         register char *cp;
 471         struct stat sbuf;
 472         struct passwd *pwd;
 473         FILE *hostf;
 474         uid_t uid;
 475         int first;
 476         char pbuf[MAXPATHLEN];
 477         const struct sockaddr *raddr;
 478         struct sockaddr_storage ss;
 479
 480         /* avoid alignment issue */
 481         if (rlen > sizeof(ss))
 482                 return(-1);
 483         memcpy(&ss, ra, rlen);
 484         raddr = (struct sockaddr *)&ss;
 485
 486         first = 1;
 487         hostf = superuser ? NULL : fopen(_PATH_HEQUIV, "r");
 488 again:
 489         if (hostf) {
 490                 if (__ivaliduser_sa(hostf, raddr, rlen, luser, ruser) == 0) {
 491                         (void)fclose(hostf);
 492                         return (0);
 493                 }
 494                 (void)fclose(hostf);
 495         }
 496         if (first == 1 && (__check_rhosts_file || superuser)) {
 497                 first = 0;
 498                 if ((pwd = getpwnam(luser)) == NULL)
 499                         return (-1);
 500                 (void)strcpy(pbuf, pwd->pw_dir);
 501                 (void)strcat(pbuf, "/.rhosts");
 502
 503                 /*
 504                  * Change effective uid while opening .rhosts.  If root and
 505                  * reading an NFS mounted file system, can't read files that
 506                  * are protected read/write owner only.
 507                  */
 508                 uid = geteuid();
 509                 (void)seteuid(pwd->pw_uid);
 510                 hostf = fopen(pbuf, "r");
 511                 (void)seteuid(uid);
 512
 513                 if (hostf == NULL)
 514                         return (-1);
 515                 /*
 516                  * If not a regular file, or is owned by someone other than
 517                  * user or root or if writeable by anyone but the owner, quit.
 518                  */
 519                 cp = NULL;
 520                 if (lstat(pbuf, &sbuf) < 0)
 521                         cp = ".rhosts lstat failed";
 522                 else if (!S_ISREG(sbuf.st_mode))
 523                         cp = ".rhosts not regular file";
 524                 else if (fstat(fileno(hostf), &sbuf) < 0)
 525                         cp = ".rhosts fstat failed";
 526                 else if (sbuf.st_uid && sbuf.st_uid != pwd->pw_uid)
 527                         cp = "bad .rhosts owner";
 528                 else if (sbuf.st_mode & (S_IWGRP|S_IWOTH))
 529                         cp = ".rhosts writeable by other than owner";
 530                 /* If there were any problems, quit. */
 531                 if (cp) {
 532                         __rcmd_errstr = cp;
 533                         (void)fclose(hostf);
 534                         return (-1);
 535                 }
 536                 goto again;
 537         }
 538         return (-1);
 539 }
 540
 541 /*
 542  * XXX
 543  * Don't make static, used by lpd(8).
 544  *
 545  * Returns 0 if ok, -1 if not ok.
 546  */
 547 int
 548 __ivaliduser(hostf, raddr, luser, ruser)
 549         FILE *hostf;
 550         u_int32_t raddr;
 551         const char *luser, *ruser;
 552 {
 553         struct sockaddr_in sin;
 554
 555         memset(&sin, 0, sizeof(sin));
 556         sin.sin_family = AF_INET;
 557         sin.sin_len = sizeof(struct sockaddr_in);
 558         memcpy(&sin.sin_addr, &raddr, sizeof(sin.sin_addr));
 559         return __ivaliduser_sa(hostf, (struct sockaddr *)&sin, sin.sin_len,
 560                 luser, ruser);
 561 }
 562
 563 /*
 564  * Returns 0 if ok, -1 if not ok.
 565  *
 566  * XXX obsolete API.
 567  */
 568 int
 569 __ivaliduser_af(hostf, raddr, luser, ruser, af, len)
 570         FILE *hostf;
 571         const void *raddr;
 572         const char *luser, *ruser;
 573         int af, len;
 574 {
 575         struct sockaddr *sa = NULL;
 576         struct sockaddr_in *sin = NULL;
 577 #ifdef INET6
 578         struct sockaddr_in6 *sin6 = NULL;
 579 #endif
 580         struct sockaddr_storage ss;
 581
 582         memset(&ss, 0, sizeof(ss));
 583         switch (af) {
 584         case AF_INET:
 585                 if (len != sizeof(sin->sin_addr))
 586                         return -1;
 587                 sin = (struct sockaddr_in *)&ss;
 588                 sin->sin_family = AF_INET;
 589                 sin->sin_len = sizeof(struct sockaddr_in);
 590                 memcpy(&sin->sin_addr, raddr, sizeof(sin->sin_addr));
 591                 break;
 592 #ifdef INET6
 593         case AF_INET6:
 594                 if (len != sizeof(sin6->sin6_addr))
 595                         return -1;
 596                 /* you will lose scope info */
 597                 sin6 = (struct sockaddr_in6 *)&ss;
 598                 sin6->sin6_family = AF_INET6;
 599                 sin6->sin6_len = sizeof(struct sockaddr_in6);
 600                 memcpy(&sin6->sin6_addr, raddr, sizeof(sin6->sin6_addr));
 601                 break;
 602 #endif
 603         default:
 604                 return -1;
 605         }
 606
 607         sa = (struct sockaddr *)&ss;
 608         return __ivaliduser_sa(hostf, sa, sa->sa_len, luser, ruser);
 609 }
 610
 611 /*
 612  * Returns 0 if ok, -1 if not ok.
 613  */
 614 int
 615 __ivaliduser_sa(hostf, raddr, salen, luser, ruser)
 616         FILE *hostf;
 617         const struct sockaddr *raddr;
 618         socklen_t salen;
 619         const char *luser, *ruser;
 620 {
 621         register char *user, *p;
 622         int ch;
 623         char buf[MAXHOSTNAMELEN + 128];         /* host + login */
 624         char hname[MAXHOSTNAMELEN];
 625         /* Presumed guilty until proven innocent. */
 626         int userok = 0, hostok = 0;
 627 #ifdef YP
 628         char *ypdomain;
 629
 630         if (yp_get_default_domain(&ypdomain))
 631                 ypdomain = NULL;
 632 #else
 633 #define ypdomain NULL
 634 #endif
 635         /* We need to get the damn hostname back for netgroup matching. */
 636         if (getnameinfo(raddr, salen, hname, sizeof(hname), NULL, 0,
 637                         NI_NAMEREQD) != 0)
 638                 return (-1);
 639
 640         while (fgets(buf, sizeof(buf), hostf)) {
 641                 p = buf;
 642                 /* Skip lines that are too long. */
 643                 if (strchr(p, '\n') == NULL) {
 644                         while ((ch = getc(hostf)) != '\n' && ch != EOF);
 645                         continue;
 646                 }
 647                 if (*p == '\n' || *p == '#') {
 648                         /* comment... */
 649                         continue;
 650                 }
 651                 while (*p != '\n' && *p != ' ' && *p != '\t' && *p != '\0') {
 652                         *p = isupper((unsigned char)*p) ? tolower((unsigned char)*p) : *p;
 653                         p++;
 654                 }
 655                 if (*p == ' ' || *p == '\t') {
 656                         *p++ = '\0';
 657                         while (*p == ' ' || *p == '\t')
 658                                 p++;
 659                         user = p;
 660                         while (*p != '\n' && *p != ' ' &&
 661                             *p != '\t' && *p != '\0')
 662                                 p++;
 663                 } else
 664                         user = p;
 665                 *p = '\0';
 666                 /*
 667                  * Do +/- and +@/-@ checking. This looks really nasty,
 668                  * but it matches SunOS's behavior so far as I can tell.
 669                  */
 670                 switch(buf[0]) {
 671                 case '+':
 672                         if (!buf[1]) {     /* '+' matches all hosts */
 673                                 hostok = 1;
 674                                 break;
 675                         }
 676                         if (buf[1] == '@')  /* match a host by netgroup */
 677                                 hostok = innetgr((char *)&buf[2],
 678                                         (char *)&hname, NULL, ypdomain);
 679                         else            /* match a host by addr */
 680                                 hostok = __icheckhost(raddr, salen,
 681                                                       (char *)&buf[1]);
 682                         break;
 683                 case '-':     /* reject '-' hosts and all their users */
 684                         if (buf[1] == '@') {
 685                                 if (innetgr((char *)&buf[2],
 686                                               (char *)&hname, NULL, ypdomain))
 687                                         return(-1);
 688                         } else {
 689                                 if (__icheckhost(raddr, salen,
 690                                                  (char *)&buf[1]))
 691                                         return(-1);
 692                         }
 693                         break;
 694                 default:  /* if no '+' or '-', do a simple match */
 695                         hostok = __icheckhost(raddr, salen, buf);
 696                         break;
 697                 }
 698                 switch(*user) {
 699                 case '+':
 700                         if (!*(user+1)) {      /* '+' matches all users */
 701                                 userok = 1;
 702                                 break;
 703                         }
 704                         if (*(user+1) == '@')  /* match a user by netgroup */
 705                                 userok = innetgr(user+2, NULL, ruser, ypdomain);
 706                         else       /* match a user by direct specification */
 707                                 userok = !(strcmp(ruser, user+1));
 708                         break;
 709                 case '-':               /* if we matched a hostname, */
 710                         if (hostok) {   /* check for user field rejections */
 711                                 if (!*(user+1))
 712                                         return(-1);
 713                                 if (*(user+1) == '@') {
 714                                         if (innetgr(user+2, NULL,
 715                                                         ruser, ypdomain))
 716                                                 return(-1);
 717                                 } else {
 718                                         if (!strcmp(ruser, user+1))
 719                                                 return(-1);
 720                                 }
 721                         }
 722                         break;
 723                 default:        /* no rejections: try to match the user */
 724                         if (hostok)
 725                                 userok = !(strcmp(ruser,*user ? user : luser));
 726                         break;
 727                 }
 728                 if (hostok && userok)
 729                         return(0);
 730         }
 731         return (-1);
 732 }
 733
 734 /*
 735  * Returns "true" if match, 0 if no match.
 736  *
 737  * NI_WITHSCOPEID is useful for comparing sin6_scope_id portion
 738  * if af == AF_INET6.
 739  */
 740 static int
 741 __icheckhost(raddr, salen, lhost)
 742         const struct sockaddr *raddr;
 743         socklen_t salen;
 744         const char *lhost;
 745 {
 746         struct sockaddr_in sin;
 747         struct sockaddr_in6 *sin6;
 748         struct addrinfo hints, *res, *r;
 749         int error;
 750         char h1[NI_MAXHOST], h2[NI_MAXHOST];
 751
 752         if (raddr->sa_family == AF_INET6) {
 753                 sin6 = (struct sockaddr_in6 *)raddr;
 754                 if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) {
 755                         memset(&sin, 0, sizeof(sin));
 756                         sin.sin_family = AF_INET;
 757                         sin.sin_len = sizeof(struct sockaddr_in);
 758                         memcpy(&sin.sin_addr, &sin6->sin6_addr.s6_addr[12],
 759                                sizeof(sin.sin_addr));
 760                         raddr = (struct sockaddr *)&sin;
 761                         salen = sin.sin_len;
 762                 }
 763         }
 764
 765         h1[0] = '\0';
 766         if (getnameinfo(raddr, salen, h1, sizeof(h1), NULL, 0,
 767                         NI_NUMERICHOST | NI_WITHSCOPEID) != 0)
 768                 return (0);
 769
 770         /* Resolve laddr into sockaddr */
 771         memset(&hints, 0, sizeof(hints));
 772         hints.ai_family = raddr->sa_family;
 773         hints.ai_socktype = SOCK_DGRAM; /*XXX dummy*/
 774         res = NULL;
 775         error = getaddrinfo(lhost, "0", &hints, &res);
 776         if (error)
 777                 return (0);
 778
 779         for (r = res; r ; r = r->ai_next) {
 780                 h2[0] = '\0';
 781                 if (getnameinfo(r->ai_addr, r->ai_addrlen, h2, sizeof(h2),
 782                                 NULL, 0, NI_NUMERICHOST | NI_WITHSCOPEID) != 0)
 783                         continue;
 784                 if (strcmp(h1, h2) == 0) {
 785                         freeaddrinfo(res);
 786                         return (1);
 787                 }
 788         }
 789
 790         /* No match. */
 791         freeaddrinfo(res);
 792         return (0);
 793 }