appl/rsh/rsh.c

   1 /*
   2  * Copyright (c) 1997 - 2004 Kungliga Tekniska Högskolan
   3  * (Royal Institute of Technology, Stockholm, Sweden).
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  *
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * 3. Neither the name of the Institute nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #include "rsh_locl.h"
  35 RCSID("$Id$");
  36
  37 enum auth_method auth_method;
  38 #if defined(KRB5)
  39 int do_encrypt       = -1;
  40 #endif
  41 #ifdef KRB5
  42 int do_unique_tkfile = 0;
  43 char *unique_tkfile  = NULL;
  44 char tkfile[MAXPATHLEN];
  45 int do_forward       = -1;
  46 int do_forwardable   = -1;
  47 krb5_context context;
  48 krb5_keyblock *keyblock;
  49 krb5_crypto crypto;
  50 #endif
  51 int sock_debug       = 0;
  52
  53 #ifdef KRB5
  54 static int use_v5 = -1;
  55 #endif
  56 #if defined(KRB5)
  57 static int use_only_broken = 0;
  58 #else
  59 static int use_only_broken = 1;
  60 #endif
  61 static int use_broken = 1;
  62 static char *port_str;
  63 static const char *user;
  64 static int do_version;
  65 static int do_help;
  66 static int do_errsock = 1;
  67 #ifdef KRB5
  68 static char *protocol_version_str;
  69 static int protocol_version = 2;
  70 #endif
  71
  72 /*
  73  *
  74  */
  75
  76 static int input = 1;           /* Read from stdin */
  77
  78 static int
  79 rsh_loop (int s, int errsock)
  80 {
  81     fd_set real_readset;
  82     int count = 1;
  83
  84 #ifdef KRB5
  85     if(auth_method == AUTH_KRB5 && protocol_version == 2)
  86         init_ivecs(1, errsock != -1);
  87 #endif
  88
  89     if (s >= FD_SETSIZE || (errsock != -1 && errsock >= FD_SETSIZE))
  90         errx (1, "fd too large");
  91
  92     FD_ZERO(&real_readset);
  93     FD_SET(s, &real_readset);
  94     if (errsock != -1) {
  95         FD_SET(errsock, &real_readset);
  96         ++count;
  97     }
  98     if(input)
  99         FD_SET(STDIN_FILENO, &real_readset);
 100
 101     for (;;) {
 102         int ret;
 103         fd_set readset;
 104         char buf[RSH_BUFSIZ];
 105
 106         readset = real_readset;
 107         ret = select (max(s, errsock) + 1, &readset, NULL, NULL, NULL);
 108         if (ret < 0) {
 109             if (errno == EINTR)
 110                 continue;
 111             else
 112                 err (1, "select");
 113         }
 114         if (FD_ISSET(s, &readset)) {
 115             ret = do_read (s, buf, sizeof(buf), ivec_in[0]);
 116             if (ret < 0)
 117                 err (1, "read");
 118             else if (ret == 0) {
 119                 close (s);
 120                 FD_CLR(s, &real_readset);
 121                 if (--count == 0)
 122                     return 0;
 123             } else
 124                 net_write (STDOUT_FILENO, buf, ret);
 125         }
 126         if (errsock != -1 && FD_ISSET(errsock, &readset)) {
 127             ret = do_read (errsock, buf, sizeof(buf), ivec_in[1]);
 128             if (ret < 0)
 129                 err (1, "read");
 130             else if (ret == 0) {
 131                 close (errsock);
 132                 FD_CLR(errsock, &real_readset);
 133                 if (--count == 0)
 134                     return 0;
 135             } else
 136                 net_write (STDERR_FILENO, buf, ret);
 137         }
 138         if (FD_ISSET(STDIN_FILENO, &readset)) {
 139             ret = read (STDIN_FILENO, buf, sizeof(buf));
 140             if (ret < 0)
 141                 err (1, "read");
 142             else if (ret == 0) {
 143                 close (STDIN_FILENO);
 144                 FD_CLR(STDIN_FILENO, &real_readset);
 145                 shutdown (s, SHUT_WR);
 146             } else
 147                 do_write (s, buf, ret, ivec_out[0]);
 148         }
 149     }
 150 }
 151
 152 #ifdef KRB5
 153 /*
 154  * Send forward information on `s' for host `hostname', them being
 155  * forwardable themselves if `forwardable'
 156  */
 157
 158 static int
 159 krb5_forward_cred (krb5_auth_context auth_context,
 160                    int s,
 161                    const char *hostname,
 162                    int forwardable)
 163 {
 164     krb5_error_code ret;
 165     krb5_ccache     ccache;
 166     krb5_creds      creds;
 167     krb5_kdc_flags  flags;
 168     krb5_data       out_data;
 169     krb5_principal  principal;
 170
 171     memset (&creds, 0, sizeof(creds));
 172
 173     ret = krb5_cc_default (context, &ccache);
 174     if (ret) {
 175         warnx ("could not forward creds: krb5_cc_default: %s",
 176                krb5_get_err_text (context, ret));
 177         return 1;
 178     }
 179
 180     ret = krb5_cc_get_principal (context, ccache, &principal);
 181     if (ret) {
 182         warnx ("could not forward creds: krb5_cc_get_principal: %s",
 183                krb5_get_err_text (context, ret));
 184         return 1;
 185     }
 186
 187     creds.client = principal;
 188
 189     ret = krb5_make_principal(context,
 190                               &creds.server,
 191                               principal->realm,
 192                               "krbtgt",
 193                               principal->realm,
 194                               NULL);
 195
 196     if (ret) {
 197         warnx ("could not forward creds: krb5_make_principal: %s",
 198                krb5_get_err_text (context, ret));
 199         return 1;
 200     }
 201
 202     creds.times.endtime = 0;
 203
 204     flags.i = 0;
 205     flags.b.forwarded   = 1;
 206     flags.b.forwardable = forwardable;
 207
 208     ret = krb5_get_forwarded_creds (context,
 209                                     auth_context,
 210                                     ccache,
 211                                     flags.i,
 212                                     hostname,
 213                                     &creds,
 214                                     &out_data);
 215     if (ret) {
 216         warnx ("could not forward creds: krb5_get_forwarded_creds: %s",
 217                krb5_get_err_text (context, ret));
 218         return 1;
 219     }
 220
 221     ret = krb5_write_message (context,
 222                               (void *)&s,
 223                               &out_data);
 224     krb5_data_free (&out_data);
 225
 226     if (ret)
 227         warnx ("could not forward creds: krb5_write_message: %s",
 228                krb5_get_err_text (context, ret));
 229     return 0;
 230 }
 231
 232 static int sendauth_version_error;
 233
 234 static int
 235 send_krb5_auth(int s,
 236                struct sockaddr *thisaddr,
 237                struct sockaddr *thataddr,
 238                const char *hostname,
 239                const char *remote_user,
 240                const char *local_user,
 241                size_t cmd_len,
 242                const char *cmd)
 243 {
 244     krb5_principal server;
 245     krb5_data cksum_data;
 246     int status;
 247     size_t len;
 248     krb5_auth_context auth_context = NULL;
 249     const char *protocol_string = NULL;
 250     krb5_flags ap_opts;
 251     char *str;
 252
 253     status = krb5_sname_to_principal(context,
 254                                      hostname,
 255                                      "host",
 256                                      KRB5_NT_SRV_HST,
 257                                      &server);
 258     if (status) {
 259         warnx ("%s: %s", hostname, krb5_get_err_text(context, status));
 260         return 1;
 261     }
 262
 263     if(do_encrypt == -1) {
 264         krb5_appdefault_boolean(context, NULL,
 265                                 krb5_principal_get_realm(context, server),
 266                                 "encrypt",
 267                                 FALSE,
 268                                 &do_encrypt);
 269     }
 270
 271     cksum_data.length = asprintf (&str,
 272                                   "%u:%s%s%s",
 273                                   ntohs(socket_get_port(thataddr)),
 274                                   do_encrypt ? "-x " : "",
 275                                   cmd,
 276                                   remote_user);
 277     if (str == NULL) {
 278         warnx ("%s: failed to allocate command", hostname);
 279         return 1;
 280     }
 281     cksum_data.data = str;
 282
 283     ap_opts = 0;
 284
 285     if(do_encrypt)
 286         ap_opts |= AP_OPTS_MUTUAL_REQUIRED;
 287
 288     switch(protocol_version) {
 289     case 2:
 290         ap_opts |= AP_OPTS_USE_SUBKEY;
 291         protocol_string = KCMD_NEW_VERSION;
 292         break;
 293     case 1:
 294         protocol_string = KCMD_OLD_VERSION;
 295         key_usage = KRB5_KU_OTHER_ENCRYPTED;
 296         break;
 297     default:
 298         abort();
 299     }
 300
 301     status = krb5_sendauth (context,
 302                             &auth_context,
 303                             &s,
 304                             protocol_string,
 305                             NULL,
 306                             server,
 307                             ap_opts,
 308                             &cksum_data,
 309                             NULL,
 310                             NULL,
 311                             NULL,
 312                             NULL,
 313                             NULL);
 314
 315     /* do this while we have a principal */
 316     if(do_forward == -1 || do_forwardable == -1) {
 317         krb5_const_realm realm = krb5_principal_get_realm(context, server);
 318         if (do_forwardable == -1)
 319             krb5_appdefault_boolean(context, NULL, realm,
 320                                     "forwardable", FALSE,
 321                                     &do_forwardable);
 322         if (do_forward == -1)
 323             krb5_appdefault_boolean(context, NULL, realm,
 324                                     "forward", FALSE,
 325                                     &do_forward);
 326     }
 327
 328     krb5_free_principal(context, server);
 329     krb5_data_free(&cksum_data);
 330
 331     if (status) {
 332         if(status == KRB5_SENDAUTH_REJECTED &&
 333            protocol_version == 2 && protocol_version_str == NULL)
 334             sendauth_version_error = 1;
 335         else
 336             krb5_warn(context, status, "%s", hostname);
 337         return 1;
 338     }
 339
 340     status = krb5_auth_con_getlocalsubkey (context, auth_context, &keyblock);
 341     if(keyblock == NULL)
 342         status = krb5_auth_con_getkey (context, auth_context, &keyblock);
 343     if (status) {
 344         warnx ("krb5_auth_con_getkey: %s", krb5_get_err_text(context, status));
 345         return 1;
 346     }
 347
 348     status = krb5_auth_con_setaddrs_from_fd (context,
 349                                              auth_context,
 350                                              &s);
 351     if (status) {
 352         warnx("krb5_auth_con_setaddrs_from_fd: %s",
 353               krb5_get_err_text(context, status));
 354         return(1);
 355     }
 356
 357     status = krb5_crypto_init(context, keyblock, 0, &crypto);
 358     if(status) {
 359         warnx ("krb5_crypto_init: %s", krb5_get_err_text(context, status));
 360         return 1;
 361     }
 362
 363     len = strlen(remote_user) + 1;
 364     if (net_write (s, remote_user, len) != len) {
 365         warn ("write");
 366         return 1;
 367     }
 368     if (do_encrypt && net_write (s, "-x ", 3) != 3) {
 369         warn ("write");
 370         return 1;
 371     }
 372     if (net_write (s, cmd, cmd_len) != cmd_len) {
 373         warn ("write");
 374         return 1;
 375     }
 376
 377     if (do_unique_tkfile) {
 378         if (net_write (s, tkfile, strlen(tkfile)) != strlen(tkfile)) {
 379             warn ("write");
 380             return 1;
 381         }
 382     }
 383     len = strlen(local_user) + 1;
 384     if (net_write (s, local_user, len) != len) {
 385         warn ("write");
 386         return 1;
 387     }
 388
 389     if (!do_forward
 390         || krb5_forward_cred (auth_context, s, hostname, do_forwardable)) {
 391         /* Empty forwarding info */
 392
 393         u_char zero[4] = {0, 0, 0, 0};
 394         write (s, &zero, 4);
 395     }
 396     krb5_auth_con_free (context, auth_context);
 397     return 0;
 398 }
 399
 400 #endif /* KRB5 */
 401
 402 static int
 403 send_broken_auth(int s,
 404                  struct sockaddr *thisaddr,
 405                  struct sockaddr *thataddr,
 406                  const char *hostname,
 407                  const char *remote_user,
 408                  const char *local_user,
 409                  size_t cmd_len,
 410                  const char *cmd)
 411 {
 412     size_t len;
 413
 414     len = strlen(local_user) + 1;
 415     if (net_write (s, local_user, len) != len) {
 416         warn ("write");
 417         return 1;
 418     }
 419     len = strlen(remote_user) + 1;
 420     if (net_write (s, remote_user, len) != len) {
 421         warn ("write");
 422         return 1;
 423     }
 424     if (net_write (s, cmd, cmd_len) != cmd_len) {
 425         warn ("write");
 426         return 1;
 427     }
 428     return 0;
 429 }
 430
 431 static int
 432 proto (int s, int errsock,
 433        const char *hostname, const char *local_user, const char *remote_user,
 434        const char *cmd, size_t cmd_len,
 435        int (*auth_func)(int s,
 436                         struct sockaddr *this, struct sockaddr *that,
 437                         const char *hostname, const char *remote_user,
 438                         const char *local_user, size_t cmd_len,
 439                         const char *cmd))
 440 {
 441     int errsock2;
 442     char buf[BUFSIZ];
 443     char *p;
 444     size_t len;
 445     char reply;
 446     struct sockaddr_storage thisaddr_ss;
 447     struct sockaddr *thisaddr = (struct sockaddr *)&thisaddr_ss;
 448     struct sockaddr_storage thataddr_ss;
 449     struct sockaddr *thataddr = (struct sockaddr *)&thataddr_ss;
 450     struct sockaddr_storage erraddr_ss;
 451     struct sockaddr *erraddr = (struct sockaddr *)&erraddr_ss;
 452     socklen_t addrlen;
 453     int ret;
 454
 455     addrlen = sizeof(thisaddr_ss);
 456     if (getsockname (s, thisaddr, &addrlen) < 0) {
 457         warn ("getsockname(%s)", hostname);
 458         return 1;
 459     }
 460     addrlen = sizeof(thataddr_ss);
 461     if (getpeername (s, thataddr, &addrlen) < 0) {
 462         warn ("getpeername(%s)", hostname);
 463         return 1;
 464     }
 465
 466     if (errsock != -1) {
 467
 468         addrlen = sizeof(erraddr_ss);
 469         if (getsockname (errsock, erraddr, &addrlen) < 0) {
 470             warn ("getsockname");
 471             return 1;
 472         }
 473
 474         if (listen (errsock, 1) < 0) {
 475             warn ("listen");
 476             return 1;
 477         }
 478
 479         p = buf;
 480         snprintf (p, sizeof(buf), "%u",
 481                   ntohs(socket_get_port(erraddr)));
 482         len = strlen(buf) + 1;
 483         if(net_write (s, buf, len) != len) {
 484             warn ("write");
 485             close (errsock);
 486             return 1;
 487         }
 488
 489
 490         for (;;) {
 491             fd_set fdset;
 492
 493             if (errsock >= FD_SETSIZE || s >= FD_SETSIZE)
 494                 errx (1, "fd too large");
 495
 496             FD_ZERO(&fdset);
 497             FD_SET(errsock, &fdset);
 498             FD_SET(s, &fdset);
 499
 500             ret = select (max(errsock, s) + 1, &fdset, NULL, NULL, NULL);
 501             if (ret < 0) {
 502                 if (errno == EINTR)
 503                     continue;
 504                 warn ("select");
 505                 close (errsock);
 506                 return 1;
 507             }
 508             if (FD_ISSET(errsock, &fdset)) {
 509                 errsock2 = accept (errsock, NULL, NULL);
 510                 close (errsock);
 511                 if (errsock2 < 0) {
 512                     warn ("accept");
 513                     return 1;
 514                 }
 515                 break;
 516             }
 517
 518             /*
 519              * there should not arrive any data on this fd so if it's
 520              * readable it probably indicates that the other side when
 521              * away.
 522              */
 523
 524             if (FD_ISSET(s, &fdset)) {
 525                 warnx ("socket closed");
 526                 close (errsock);
 527                 errsock2 = -1;
 528                 break;
 529             }
 530         }
 531     } else {
 532         if (net_write (s, "0", 2) != 2) {
 533             warn ("write");
 534             return 1;
 535         }
 536         errsock2 = -1;
 537     }
 538
 539     if ((*auth_func)(s, thisaddr, thataddr, hostname,
 540                      remote_user, local_user,
 541                      cmd_len, cmd)) {
 542         close (errsock2);
 543         return 1;
 544     }
 545
 546     ret = net_read (s, &reply, 1);
 547     if (ret < 0) {
 548         warn ("read");
 549         close (errsock2);
 550         return 1;
 551     } else if (ret == 0) {
 552         warnx ("unexpected EOF from %s", hostname);
 553         close (errsock2);
 554         return 1;
 555     }
 556     if (reply != 0) {
 557
 558         warnx ("Error from rshd at %s:", hostname);
 559
 560         while ((ret = read (s, buf, sizeof(buf))) > 0)
 561             write (STDOUT_FILENO, buf, ret);
 562         write (STDOUT_FILENO,"\n",1);
 563         close (errsock2);
 564         return 1;
 565     }
 566
 567     if (sock_debug) {
 568         int one = 1;
 569         if (setsockopt(s, SOL_SOCKET, SO_DEBUG, (void *)&one, sizeof(one)) < 0)
 570             warn("setsockopt remote");
 571         if (errsock2 != -1 &&
 572             setsockopt(errsock2, SOL_SOCKET, SO_DEBUG,
 573                        (void *)&one, sizeof(one)) < 0)
 574             warn("setsockopt stderr");
 575     }
 576
 577     return rsh_loop (s, errsock2);
 578 }
 579
 580 /*
 581  * Return in `res' a copy of the concatenation of `argc, argv' into
 582  * malloced space.  */
 583
 584 static size_t
 585 construct_command (char **res, int argc, char **argv)
 586 {
 587     int i;
 588     size_t len = 0;
 589     char *tmp;
 590
 591     for (i = 0; i < argc; ++i)
 592         len += strlen(argv[i]) + 1;
 593     len = max (1, len);
 594     tmp = malloc (len);
 595     if (tmp == NULL)
 596         errx (1, "malloc %lu failed", (unsigned long)len);
 597
 598     *tmp = '\0';
 599     for (i = 0; i < argc - 1; ++i) {
 600         strlcat (tmp, argv[i], len);
 601         strlcat (tmp, " ", len);
 602     }
 603     if (argc > 0)
 604         strlcat (tmp, argv[argc-1], len);
 605     *res = tmp;
 606     return len;
 607 }
 608
 609 static char *
 610 print_addr (const struct sockaddr *sa)
 611 {
 612     char addr_str[256];
 613     char *res;
 614     const char *as = NULL;
 615
 616     if(sa->sa_family == AF_INET)
 617         as = inet_ntop (sa->sa_family, &((struct sockaddr_in*)sa)->sin_addr,
 618                         addr_str, sizeof(addr_str));
 619 #ifdef HAVE_INET6
 620     else if(sa->sa_family == AF_INET6)
 621         as = inet_ntop (sa->sa_family, &((struct sockaddr_in6*)sa)->sin6_addr,
 622                         addr_str, sizeof(addr_str));
 623 #endif
 624     if(as == NULL)
 625         return NULL;
 626     res = strdup(as);
 627     if (res == NULL)
 628         errx (1, "malloc: out of memory");
 629     return res;
 630 }
 631
 632 static int
 633 doit_broken (int argc,
 634              char **argv,
 635              int hostindex,
 636              struct addrinfo *ai,
 637              const char *remote_user,
 638              const char *local_user,
 639              int priv_socket1,
 640              int priv_socket2,
 641              const char *cmd,
 642              size_t cmd_len)
 643 {
 644     struct addrinfo *a;
 645
 646     if (connect (priv_socket1, ai->ai_addr, ai->ai_addrlen) < 0) {
 647         int save_errno = errno;
 648
 649         close(priv_socket1);
 650         close(priv_socket2);
 651
 652         for (a = ai->ai_next; a != NULL; a = a->ai_next) {
 653             pid_t pid;
 654             char *adr = print_addr(a->ai_addr);
 655             if(adr == NULL)
 656                 continue;
 657
 658             pid = fork();
 659             if (pid < 0)
 660                 err (1, "fork");
 661             else if(pid == 0) {
 662                 char **new_argv;
 663                 int i = 0;
 664
 665                 new_argv = malloc((argc + 2) * sizeof(*new_argv));
 666                 if (new_argv == NULL)
 667                     errx (1, "malloc: out of memory");
 668                 new_argv[i] = argv[i];
 669                 ++i;
 670                 if (hostindex == i)
 671                     new_argv[i++] = adr;
 672                 new_argv[i++] = "-K";
 673                 for(; i <= argc; ++i)
 674                     new_argv[i] = argv[i - 1];
 675                 if (hostindex > 1)
 676                     new_argv[hostindex + 1] = adr;
 677                 new_argv[argc + 1] = NULL;
 678                 execv(PATH_RSH, new_argv);
 679                 err(1, "execv(%s)", PATH_RSH);
 680             } else {
 681                 int status;
 682                 free(adr);
 683
 684                 while(waitpid(pid, &status, 0) < 0)
 685                     ;
 686                 if(WIFEXITED(status) && WEXITSTATUS(status) == 0)
 687                     return 0;
 688             }
 689         }
 690         errno = save_errno;
 691         warn("%s", argv[hostindex]);
 692         return 1;
 693     } else {
 694         int ret;
 695
 696         ret = proto (priv_socket1, priv_socket2,
 697                      argv[hostindex],
 698                      local_user, remote_user,
 699                      cmd, cmd_len,
 700                      send_broken_auth);
 701         return ret;
 702     }
 703 }
 704
 705 #if defined(KRB5)
 706 static int
 707 doit (const char *hostname,
 708       struct addrinfo *ai,
 709       const char *remote_user,
 710       const char *local_user,
 711       const char *cmd,
 712       size_t cmd_len,
 713       int (*auth_func)(int s,
 714                        struct sockaddr *this, struct sockaddr *that,
 715                        const char *hostname, const char *remote_user,
 716                        const char *local_user, size_t cmd_len,
 717                        const char *cmd))
 718 {
 719     int error;
 720     struct addrinfo *a;
 721     int socketfailed = 1;
 722     int ret;
 723
 724     for (a = ai; a != NULL; a = a->ai_next) {
 725         int s;
 726         int errsock;
 727
 728         s = socket (a->ai_family, a->ai_socktype, a->ai_protocol);
 729         if (s < 0)
 730             continue;
 731         socketfailed = 0;
 732         if (connect (s, a->ai_addr, a->ai_addrlen) < 0) {
 733             char addr[128];
 734             if(getnameinfo(a->ai_addr, a->ai_addrlen,
 735                            addr, sizeof(addr), NULL, 0, NI_NUMERICHOST) == 0)
 736                 warn ("connect(%s [%s])", hostname, addr);
 737             else
 738                 warn ("connect(%s)", hostname);
 739             close (s);
 740             continue;
 741         }
 742         if (do_errsock) {
 743             struct addrinfo *ea, *eai;
 744             struct addrinfo hints;
 745
 746             memset (&hints, 0, sizeof(hints));
 747             hints.ai_socktype = a->ai_socktype;
 748             hints.ai_protocol = a->ai_protocol;
 749             hints.ai_family   = a->ai_family;
 750             hints.ai_flags    = AI_PASSIVE;
 751
 752             errsock = -1;
 753
 754             error = getaddrinfo (NULL, "0", &hints, &eai);
 755             if (error)
 756                 errx (1, "getaddrinfo: %s", gai_strerror(error));
 757             for (ea = eai; ea != NULL; ea = ea->ai_next) {
 758                 errsock = socket (ea->ai_family, ea->ai_socktype,
 759                                   ea->ai_protocol);
 760                 if (errsock < 0)
 761                     continue;
 762                 if (bind (errsock, ea->ai_addr, ea->ai_addrlen) < 0)
 763                     err (1, "bind");
 764                 break;
 765             }
 766             if (errsock < 0)
 767                 err (1, "socket");
 768             freeaddrinfo (eai);
 769         } else
 770             errsock = -1;
 771
 772         ret = proto (s, errsock,
 773                      hostname,
 774                      local_user, remote_user,
 775                      cmd, cmd_len, auth_func);
 776         close (s);
 777         return ret;
 778     }
 779     if(socketfailed)
 780         warnx ("failed to contact %s", hostname);
 781     return -1;
 782 }
 783 #endif /* KRB5 */
 784
 785 struct getargs args[] = {
 786 #ifdef KRB5
 787     { "krb5",   '5', arg_flag,          &use_v5,        "Use Kerberos V5" },
 788     { "forward", 'f', arg_flag,         &do_forward,    "Forward credentials [krb5]"},
 789     { "forwardable", 'F', arg_flag,     &do_forwardable,
 790       "Forward forwardable credentials [krb5]" },
 791     { NULL, 'G', arg_negative_flag,&do_forward, "Don't forward credentials" },
 792     { "unique", 'u', arg_flag,  &do_unique_tkfile,
 793       "Use unique remote credentials cache [krb5]" },
 794     { "tkfile", 'U', arg_string,  &unique_tkfile,
 795       "Specifies remote credentials cache [krb5]" },
 796     { "protocol", 'P', arg_string,      &protocol_version_str,
 797       "Protocol version [krb5]", "protocol" },
 798 #endif
 799     { "broken", 'K', arg_flag,          &use_only_broken, "Use only priv port" },
 800 #if defined(KRB5)
 801     { "encrypt", 'x', arg_flag,         &do_encrypt,    "Encrypt connection" },
 802     { NULL,     'z', arg_negative_flag,      &do_encrypt,
 803       "Don't encrypt connection", NULL },
 804 #endif
 805     { NULL,     'd', arg_flag,          &sock_debug, "Enable socket debugging" },
 806     { "input",  'n', arg_negative_flag, &input,         "Close stdin" },
 807     { "port",   'p', arg_string,        &port_str,      "Use this port",
 808       "port" },
 809     { "user",   'l', arg_string,        &user,          "Run as this user", "login" },
 810     { "stderr", 'e', arg_negative_flag, &do_errsock,    "Don't open stderr"},
 811 #ifdef KRB5
 812 #endif
 813     { "version", 0,  arg_flag,          &do_version,    NULL },
 814     { "help",    0,  arg_flag,          &do_help,       NULL }
 815 };
 816
 817 static void
 818 usage (int ret)
 819 {
 820     arg_printusage (args,
 821                     sizeof(args) / sizeof(args[0]),
 822                     NULL,
 823                     "[login@]host [command]");
 824     exit (ret);
 825 }
 826
 827 /*
 828  *
 829  */
 830
 831 int
 832 main(int argc, char **argv)
 833 {
 834     int priv_port1, priv_port2;
 835     int priv_socket1, priv_socket2;
 836     int argindex = 0;
 837     int error;
 838     struct addrinfo hints, *ai;
 839     int ret = 1;
 840     char *cmd;
 841     char *tmp;
 842     size_t cmd_len;
 843     const char *local_user;
 844     char *host = NULL;
 845     int host_index = -1;
 846 #ifdef KRB5
 847     int status;
 848 #endif
 849     uid_t uid;
 850
 851     priv_port1 = priv_port2 = IPPORT_RESERVED-1;
 852     priv_socket1 = rresvport(&priv_port1);
 853     priv_socket2 = rresvport(&priv_port2);
 854     uid = getuid ();
 855     if (setuid (uid) || (uid != 0 && setuid(0) == 0))
 856         err (1, "setuid");
 857
 858     setprogname (argv[0]);
 859
 860     if (argc >= 2 && argv[1][0] != '-') {
 861         host = argv[host_index = 1];
 862         argindex = 1;
 863     }
 864
 865     if (getarg (args, sizeof(args) / sizeof(args[0]), argc, argv,
 866                 &argindex))
 867         usage (1);
 868
 869     if (do_help)
 870         usage (0);
 871
 872     if (do_version) {
 873         print_version (NULL);
 874         return 0;
 875     }
 876
 877 #ifdef KRB5
 878     if(protocol_version_str != NULL) {
 879         if(strcasecmp(protocol_version_str, "N") == 0)
 880             protocol_version = 2;
 881         else if(strcasecmp(protocol_version_str, "O") == 0)
 882             protocol_version = 1;
 883         else {
 884             char *end;
 885             int v;
 886             v = strtol(protocol_version_str, &end, 0);
 887             if(*end != '\0' || (v != 1 && v != 2)) {
 888                 errx(1, "unknown protocol version \"%s\"",
 889                      protocol_version_str);
 890             }
 891             protocol_version = v;
 892         }
 893     }
 894
 895     status = krb5_init_context (&context);
 896     if (status) {
 897         if(use_v5 == 1)
 898             errx(1, "krb5_init_context failed: %d", status);
 899         else
 900             use_v5 = 0;
 901     }
 902
 903     /* request for forwardable on the command line means we should
 904        also forward */
 905     if (do_forwardable == 1)
 906         do_forward = 1;
 907
 908 #endif
 909
 910     if (use_only_broken) {
 911 #ifdef KRB5
 912         use_v5 = 0;
 913 #endif
 914     }
 915
 916     if(priv_socket1 < 0) {
 917         if (use_only_broken)
 918             errx (1, "unable to bind reserved port: is rsh setuid root?");
 919         use_broken = 0;
 920     }
 921
 922 #if defined(KRB5)
 923     if (do_encrypt == 1 && use_only_broken)
 924         errx (1, "encryption not supported with old style authentication");
 925 #endif
 926
 927
 928
 929 #ifdef KRB5
 930     if (do_unique_tkfile && unique_tkfile != NULL)
 931         errx (1, "Only one of -u and -U allowed.");
 932
 933     if (do_unique_tkfile)
 934         strlcpy(tkfile,"-u ", sizeof(tkfile));
 935     else if (unique_tkfile != NULL) {
 936         if (strchr(unique_tkfile,' ') != NULL) {
 937             warnx("Space is not allowed in tkfilename");
 938             usage(1);
 939         }
 940         do_unique_tkfile = 1;
 941         snprintf (tkfile, sizeof(tkfile), "-U %s ", unique_tkfile);
 942     }
 943 #endif
 944
 945     if (host == NULL) {
 946         if (argc - argindex < 1)
 947             usage (1);
 948         else
 949             host = argv[host_index = argindex++];
 950     }
 951
 952     if((tmp = strchr(host, '@')) != NULL) {
 953         *tmp++ = '\0';
 954         user = host;
 955         host = tmp;
 956     }
 957
 958     if (argindex == argc) {
 959         close (priv_socket1);
 960         close (priv_socket2);
 961         argv[0] = "rlogin";
 962         execvp ("rlogin", argv);
 963         err (1, "execvp rlogin");
 964     }
 965
 966     local_user = get_default_username ();
 967     if (local_user == NULL)
 968         errx (1, "who are you?");
 969
 970     if (user == NULL)
 971         user = local_user;
 972
 973     cmd_len = construct_command(&cmd, argc - argindex, argv + argindex);
 974
 975     /*
 976      * Try all different authentication methods
 977      */
 978
 979 #ifdef KRB5
 980     if (ret && use_v5) {
 981         memset (&hints, 0, sizeof(hints));
 982         hints.ai_socktype = SOCK_STREAM;
 983         hints.ai_protocol = IPPROTO_TCP;
 984
 985         if(port_str == NULL) {
 986             error = getaddrinfo(host, "kshell", &hints, &ai);
 987             if(error == EAI_NONAME)
 988                 error = getaddrinfo(host, "544", &hints, &ai);
 989         } else
 990             error = getaddrinfo(host, port_str, &hints, &ai);
 991
 992         if(error)
 993             errx (1, "getaddrinfo: %s", gai_strerror(error));
 994
 995         auth_method = AUTH_KRB5;
 996       again:
 997         ret = doit (host, ai, user, local_user, cmd, cmd_len,
 998                     send_krb5_auth);
 999         if(ret != 0 && sendauth_version_error &&
1000            protocol_version == 2) {
1001             protocol_version = 1;
1002             goto again;
1003         }
1004         freeaddrinfo(ai);
1005     }
1006 #endif
1007     if (ret && use_broken) {
1008         memset (&hints, 0, sizeof(hints));
1009         hints.ai_socktype = SOCK_STREAM;
1010         hints.ai_protocol = IPPROTO_TCP;
1011
1012         if(port_str == NULL) {
1013             error = getaddrinfo(host, "shell", &hints, &ai);
1014             if(error == EAI_NONAME)
1015                 error = getaddrinfo(host, "514", &hints, &ai);
1016         } else
1017             error = getaddrinfo(host, port_str, &hints, &ai);
1018
1019         if(error)
1020             errx (1, "getaddrinfo: %s", gai_strerror(error));
1021
1022         auth_method = AUTH_BROKEN;
1023         ret = doit_broken (argc, argv, host_index, ai,
1024                            user, local_user,
1025                            priv_socket1,
1026                            do_errsock ? priv_socket2 : -1,
1027                            cmd, cmd_len);
1028         freeaddrinfo(ai);
1029     }
1030     free(cmd);
1031     return ret;
1032 }