vfs/mcserv.c

   1 /* Server for the Midnight Commander Virtual File System.
   2
   3    Copyright (C) 1995, 1996, 1997 The Free Software Foundation
   4
   5    Written by:
   6       Miguel de Icaza, 1995, 1997,
   7       Andrej Borsenkow 1996.
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 2 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program; if not, write to the Free Software
  21    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  22
  23    TODO:
  24    opendir instead of keeping its table of file handles could return
  25    the pointer and expect the client to send a proper value back each
  26    time :-)
  27
  28    We should use syslog to register login/logout.
  29
  30     */
  31
  32 /* {{{ Includes and global variables */
  33
  34 #include <config.h>
  35 #include <stdio.h>
  36 #include <stdlib.h>
  37 #ifdef HAVE_UNISTD_H
  38 #    include <unistd.h>
  39 #endif
  40 #include <fcntl.h>
  41 #include <string.h>
  42 #ifdef HAVE_LIMITS_H
  43 #    include <limits.h>
  44 #endif
  45 #ifndef NGROUPS_MAX
  46 #    include <sys/param.h>
  47 #    ifdef NGROUPS
  48 #        define NGROUPS_MAX NGROUPS
  49 #    endif
  50 #endif
  51 #ifdef HAVE_GRP_H
  52 #    include <grp.h>
  53 #endif
  54 #ifdef HAVE_SHADOW_H
  55 #    include <shadow.h>
  56 #else
  57 #    ifdef HAVE_SHADOW_SHADOW_H
  58 #        include <shadow/shadow.h>
  59 #    endif
  60 #endif
  61 #ifdef HAVE_CRYPT_H
  62 #    include <crypt.h>
  63 #endif
  64 #include <sys/types.h>
  65 #include <sys/stat.h>
  66 #include <sys/wait.h>
  67 #include <errno.h>
  68 #include <signal.h>
  69
  70 /* Network include files */
  71 #include <sys/socket.h>
  72 #include <netinet/in.h>
  73 #include <netdb.h>
  74 #include <arpa/inet.h>
  75 #ifdef HAVE_PMAP_SET
  76 #    include <rpc/rpc.h>
  77 #    include <rpc/pmap_prot.h>
  78 #    ifdef HAVE_RPC_PMAP_CLNT_H
  79 #        include <rpc/pmap_clnt.h>
  80 #    endif
  81 #endif
  82
  83 /* Authentication include files */
  84 #include <pwd.h>
  85 #ifdef HAVE_PAM
  86 #    include <security/pam_misc.h>
  87 #    ifndef PAM_ESTABLISH_CRED
  88 #        define PAM_ESTABLISH_CRED PAM_CRED_ESTABLISH
  89 #    endif
  90 #endif
  91
  92 #include "utilvfs.h"
  93
  94 #include "vfs.h"
  95 #include "mcfs.h"
  96 #include "tcputil.h"
  97
  98 /* The socket from which we accept commands */
  99 int msock;
 100
 101 /* Requested version number from client */
 102 static int clnt_version;
 103
 104 /* If non zero, we accept further commands */
 105 int logged_in = 0;
 106
 107 /* Home directory */
 108 char *home_dir = NULL;
 109
 110 char *up_dir = NULL;
 111
 112 /* Were we started from inetd? */
 113 int  inetd_started = 0;
 114
 115 /* Are we running as a daemon? */
 116 int  isDaemon = 0;
 117
 118 /* guess */
 119 int verbose = 0;
 120
 121 /* ftp auth */
 122 int ftp = 0;
 123
 124 /* port number in which we listen to connections,
 125  * if zero, we try to contact the portmapper to get a port, and
 126  * if it's not possible, then we use a hardcoded value
 127  */
 128 int portnum = 0;
 129
 130 /* if the server will use rcmd based authentication (hosts.equiv .rhosts) */
 131 int r_auth = 0;
 132
 133 #define OPENDIR_HANDLES 8
 134
 135 #define DO_QUIT_VOID() \
 136 do { \
 137   quit_server = 1; \
 138   return_code = 1; \
 139   return; \
 140 } while (0)
 141
 142 /* Only used by get_port_number */
 143 #define DO_QUIT_NONVOID(a) \
 144 do { \
 145   quit_server = 1; \
 146   return_code = 1; \
 147   return (a); \
 148 } while (0)
 149
 150 char buffer [4096];
 151 int debug = 1;
 152 static int quit_server;
 153 static int return_code;
 154
 155 /* }}} */
 156
 157 /* {{{ Misc routines */
 158
 159 static void send_status (int status, int errno_number)
 160 {
 161     rpc_send (msock, RPC_INT, status, RPC_INT, errno_number, RPC_END);
 162     errno = 0;
 163 }
 164
 165 /* }}} */
 166
 167 /* {{{ File with handle operations */
 168
 169 static void do_open (void)
 170 {
 171     int handle, flags, mode;
 172     char *arg;
 173
 174     rpc_get (msock, RPC_STRING, &arg, RPC_INT, &flags, RPC_INT, &mode,RPC_END);
 175
 176     handle = open (arg, flags, mode);
 177     send_status (handle, errno);
 178     g_free (arg);
 179 }
 180
 181 static void do_read (void)
 182 {
 183     int handle, count, n;
 184     void *data;
 185
 186     rpc_get (msock, RPC_INT, &handle, RPC_INT, &count, RPC_END);
 187     data = g_malloc (count);
 188     if (!data){
 189         send_status (-1, ENOMEM);
 190         return;
 191     }
 192     if (verbose) printf ("count=%d\n", count);
 193     n = read (handle, data, count);
 194     if (verbose) printf ("result=%d\n", n);
 195     if (n < 0){
 196         send_status (-1, errno);
 197         return;
 198     }
 199     send_status (n, 0);
 200     rpc_send (msock, RPC_BLOCK, n, data, RPC_END);
 201
 202     g_free (data);
 203 }
 204
 205 static void do_write (void)
 206 {
 207     int handle, count, status, written = 0;
 208     char buf[8192];
 209
 210     rpc_get (msock, RPC_INT, &handle, RPC_INT, &count, RPC_END);
 211     status = 0;
 212     while (count) {
 213         int nbytes = count > 8192 ? 8192 : count;
 214
 215         rpc_get (msock, RPC_BLOCK, nbytes, buf, RPC_END);
 216         status = write (handle, buf, nbytes);
 217         if (status < 0) {
 218             send_status (status, errno);
 219             return;
 220         }
 221         /* FIXED: amount written must be returned to caller */
 222         written += status;
 223         if (status < nbytes) {
 224             send_status (written, errno);
 225             return;
 226         }
 227         count -= nbytes;
 228     }
 229     send_status (written, errno);
 230 }
 231
 232 static void do_lseek (void)
 233 {
 234     int handle, offset, whence, status;
 235
 236     rpc_get (msock,
 237              RPC_INT, &handle,
 238              RPC_INT, &offset,
 239              RPC_INT, &whence, RPC_END);
 240     status = lseek (handle, offset, whence);
 241     send_status (status, errno);
 242 }
 243
 244 static void do_close (void)
 245 {
 246     int handle, status;
 247
 248     rpc_get (msock, RPC_INT, &handle, RPC_END);
 249     status = close (handle);
 250     send_status (status, errno);
 251 }
 252
 253 /* }}} */
 254
 255 /* {{{ Stat family routines */
 256
 257 static void send_time (int sock, time_t time)
 258 {
 259     if (clnt_version == 1) {
 260         char   *ct;
 261         int    month;
 262
 263         ct = ctime (&time);
 264         ct [3] = ct [10] = ct [13] = ct [16] = ct [19] = 0;
 265
 266         /* Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec */
 267         if (ct [4] == 'J'){
 268             if (ct [5] == 'a'){
 269                 month = 0;
 270             } else
 271                 month = (ct [6] == 'n') ? 5 : 6;
 272         } else if (ct [4] == 'F'){
 273             month = 1;
 274         } else if (ct [4] == 'M'){
 275             month = (ct [6] == 'r') ? 2 : 5;
 276         } else if (ct [4] == 'A'){
 277             month = (ct [5] == 'p') ? 3 : 7;
 278         } else if (ct [4] == 'S'){
 279             month = 8;
 280         } else if (ct [4] == 'O'){
 281             month = 9;
 282         } else if (ct [4] == 'N'){
 283             month = 10;
 284         } else
 285         month = 11;
 286         rpc_send (msock,
 287                   RPC_INT, atoi (&ct [17]),     /* sec */
 288                   RPC_INT, atoi (&ct [14]),         /* min */
 289                   RPC_INT, atoi (&ct [11]),         /* hour */
 290                   RPC_INT, atoi (&ct [8]),          /* mday */
 291                   RPC_INT, atoi (&ct [20]),         /* year */
 292                   RPC_INT, month,                       /* month */
 293                   RPC_END);
 294     } else {
 295         long ltime = (long) time;
 296         char buf[BUF_SMALL];
 297
 298         g_snprintf (buf, sizeof(buf), "%lx", ltime);
 299         rpc_send (msock,
 300                   RPC_STRING, buf,
 301                   RPC_END);
 302     }
 303 }
 304
 305 static void send_stat_info (struct stat *st)
 306 {
 307     long mylong;
 308     int blocks =
 309 #ifdef HAVE_ST_BLOCKS
 310         st->st_blocks;
 311 #else
 312         st->st_size / 1024;
 313 #endif
 314
 315 #ifdef HAVE_ST_RDEV
 316     mylong = st->st_rdev;
 317 #else
 318     mylong = 0;
 319 #endif
 320     rpc_send (msock, RPC_INT, (long) mylong,
 321               RPC_INT, (long) st->st_ino,
 322               RPC_INT, (long) st->st_mode,
 323               RPC_INT, (long) st->st_nlink,
 324               RPC_INT, (long) st->st_uid,
 325               RPC_INT, (long) st->st_gid,
 326               RPC_INT, (long) st->st_size,
 327               RPC_INT, (long) blocks, RPC_END);
 328     send_time (msock, st->st_atime);
 329     send_time (msock, st->st_mtime);
 330     send_time (msock, st->st_ctime);
 331 }
 332
 333 static void do_lstat (void)
 334 {
 335     struct stat st;
 336     char   *file;
 337     int    n;
 338
 339     rpc_get (msock, RPC_STRING, &file, RPC_END);
 340     n = lstat (file, &st);
 341     send_status (n, errno);
 342     if (n >= 0)
 343         send_stat_info (&st);
 344     g_free (file);
 345 }
 346
 347 static void do_fstat (void)
 348 {
 349     int handle;
 350     int n;
 351     struct stat st;
 352
 353     rpc_get (msock, RPC_INT, &handle, RPC_END);
 354     n = fstat (handle, &st);
 355     send_status (n, errno);
 356     if (n < 0)
 357         return;
 358
 359     send_stat_info (&st);
 360 }
 361
 362 static void do_stat (void)
 363 {
 364     struct stat st;
 365     int    n;
 366     char   *file;
 367
 368     rpc_get (msock, RPC_STRING, &file, RPC_END);
 369
 370     n = stat (file, &st);
 371     send_status (n, errno);
 372     if (n >= 0)
 373         send_stat_info (&st);
 374     g_free (file);
 375 }
 376
 377 /* }}} */
 378
 379 /* {{{ Directory lookup operations */
 380
 381 static struct {
 382     int used;
 383     DIR *dirs [OPENDIR_HANDLES];
 384     char *names [OPENDIR_HANDLES];
 385 } mcfs_DIR;
 386
 387 static void close_handle (int handle)
 388 {
 389     if (mcfs_DIR.used > 0) mcfs_DIR.used--;
 390     if (mcfs_DIR.dirs [handle])
 391         closedir (mcfs_DIR.dirs [handle]);
 392     if (mcfs_DIR.names [handle])
 393         g_free (mcfs_DIR.names [handle]);
 394     mcfs_DIR.dirs [handle] = 0;
 395     mcfs_DIR.names [handle] = 0;
 396 }
 397
 398 static void do_opendir (void)
 399 {
 400     int handle, i;
 401     char *arg;
 402     DIR *p;
 403
 404     rpc_get (msock, RPC_STRING, &arg, RPC_END);
 405
 406     if (mcfs_DIR.used == OPENDIR_HANDLES){
 407         send_status (-1, ENFILE);       /* Error */
 408         g_free (arg);
 409         return;
 410     }
 411
 412     handle = -1;
 413     for (i = 0; i < OPENDIR_HANDLES; i++){
 414         if (mcfs_DIR.dirs [i] == 0){
 415             handle = i;
 416             break;
 417         }
 418     }
 419
 420     if (handle == -1){
 421         send_status (-1, EMFILE);
 422         g_free (arg);
 423         if (!inetd_started)
 424             fprintf (stderr, "OOPS! you have found a bug in mc - do_opendir()!\n");
 425         return;
 426     }
 427
 428     if (verbose) printf ("handle=%d\n", handle);
 429     p = opendir (arg);
 430     if (p){
 431         mcfs_DIR.dirs [handle] = p;
 432         mcfs_DIR.names [handle] = arg;
 433             mcfs_DIR.used ++;
 434
 435         /* Because 0 is an error value */
 436         rpc_send (msock, RPC_INT, handle+1, RPC_INT, 0, RPC_END);
 437
 438     } else {
 439         send_status (-1, errno);
 440         g_free (arg);
 441     }
 442 }
 443
 444 /* Sends the complete directory listing, as well as the stat information */
 445 static void do_readdir (void)
 446 {
 447     struct dirent *dirent;
 448     struct stat st;
 449     int    handle, n;
 450     char   *fname = 0;
 451
 452     rpc_get (msock, RPC_INT, &handle, RPC_END);
 453
 454     if (!handle){
 455         rpc_send (msock, RPC_INT, 0, RPC_END);
 456         return;
 457     }
 458
 459     /* We incremented it in opendir */
 460     handle --;
 461
 462     while ((dirent = readdir (mcfs_DIR.dirs [handle]))){
 463         int length = NLENGTH (dirent);
 464
 465         rpc_send (msock, RPC_INT, length, RPC_END);
 466         rpc_send (msock, RPC_BLOCK, length, dirent->d_name, RPC_END);
 467         fname = g_strconcat (mcfs_DIR.names [handle],
 468                                 PATH_SEP_STR, dirent->d_name, NULL);
 469         n = lstat (fname, &st);
 470         send_status (n, errno);
 471         g_free (fname);
 472         if (n >= 0)
 473             send_stat_info (&st);
 474     }
 475     rpc_send (msock, RPC_INT, 0, RPC_END);
 476 }
 477
 478 static void do_closedir (void)
 479 {
 480     int handle;
 481
 482     rpc_get (msock, RPC_INT, &handle, RPC_END);
 483     close_handle (handle-1);
 484 }
 485
 486 /* }}} */
 487
 488 /* {{{ Operations with one and two file name argument */
 489
 490 static void do_chdir (void)
 491 {
 492     char *file;
 493     int  status;
 494
 495     rpc_get (msock, RPC_STRING, &file, RPC_END);
 496
 497     status = chdir (file);
 498     send_status (status, errno);
 499     g_free (file);
 500 }
 501
 502 static void do_rmdir (void)
 503 {
 504     char *file;
 505     int  status;
 506
 507     rpc_get (msock, RPC_STRING, &file, RPC_END);
 508
 509     status = rmdir (file);
 510     send_status (status, errno);
 511     g_free (file);
 512 }
 513
 514 static void do_mkdir (void)
 515 {
 516     char *file;
 517     int  mode, status;
 518
 519     rpc_get (msock, RPC_STRING, &file, RPC_INT, &mode, RPC_END);
 520
 521     status = mkdir (file, mode);
 522     send_status (status, errno);
 523     g_free (file);
 524 }
 525
 526 static void do_mknod (void)
 527 {
 528     char *file;
 529     int  mode, dev, status;
 530
 531     rpc_get (msock, RPC_STRING, &file, RPC_INT, &mode, RPC_INT, &dev, RPC_END);
 532
 533     status = mknod (file, mode, dev);
 534     send_status (status, errno);
 535     g_free (file);
 536 }
 537
 538 static void do_readlink (void)
 539 {
 540     char buffer [2048];
 541     char *file;
 542     int  n;
 543
 544     rpc_get (msock, RPC_STRING, &file, RPC_END);
 545     n = readlink (file, buffer, 2048);
 546     send_status (n, errno);
 547     if (n >= 0) {
 548         buffer [n] = 0;
 549         rpc_send (msock, RPC_STRING, buffer, RPC_END);
 550     }
 551     g_free (file);
 552 }
 553
 554 static void do_unlink (void)
 555 {
 556     char *file;
 557     int  status;
 558
 559     rpc_get (msock, RPC_STRING, &file, RPC_END);
 560     status = unlink (file);
 561     send_status (status, errno);
 562     g_free (file);
 563 }
 564
 565 static void do_rename (void)
 566 {
 567     char *f1, *f2;
 568     int  status;
 569
 570     rpc_get (msock, RPC_STRING, &f1, RPC_STRING, &f2, RPC_END);
 571     status = rename (f1, f2);
 572     send_status (status, errno);
 573     g_free (f1); g_free (f2);
 574 }
 575
 576 static void do_symlink (void)
 577 {
 578     char *f1, *f2;
 579     int  status;
 580
 581     rpc_get (msock, RPC_STRING, &f1, RPC_STRING, &f2, RPC_END);
 582     status = symlink (f1, f2);
 583     send_status (status, errno);
 584     g_free (f1); g_free (f2);
 585 }
 586
 587 static void do_link (void)
 588 {
 589     char *f1, *f2;
 590     int  status;
 591
 592     rpc_get (msock, RPC_STRING, &f1, RPC_STRING, &f2, RPC_END);
 593     status = link (f1, f2);
 594     send_status (status, errno);
 595     g_free (f1); g_free (f2);
 596 }
 597
 598
 599 /* }}} */
 600
 601 /* {{{ Misc commands */
 602
 603 static void do_gethome (void)
 604 {
 605     rpc_send (msock, RPC_STRING, (home_dir) ? home_dir : "/", RPC_END);
 606 }
 607
 608 static void do_getupdir (void)
 609 {
 610     rpc_send (msock, RPC_STRING, (up_dir) ? up_dir : "/", RPC_END);
 611 }
 612
 613 static void do_chmod (void)
 614 {
 615     char *file;
 616     int  mode, status;
 617
 618     rpc_get (msock, RPC_STRING, &file, RPC_INT, &mode, RPC_END);
 619     status = chmod (file, mode);
 620     send_status (status, errno);
 621     g_free (file);
 622 }
 623
 624 static void do_chown (void)
 625 {
 626     char *file;
 627     int  owner, group, status;
 628
 629     rpc_get (msock, RPC_STRING, &file,RPC_INT, &owner, RPC_INT,&group,RPC_END);
 630     status = chown (file, owner, group);
 631     send_status (status, errno);
 632     g_free (file);
 633 }
 634
 635 static void do_utime (void)
 636 {
 637     char *file;
 638     int  status;
 639     long atime;
 640     long mtime;
 641     char *as;
 642     char *ms;
 643     struct utimbuf times;
 644
 645     rpc_get (msock, RPC_STRING, &file,
 646                     RPC_STRING, &as,
 647                     RPC_STRING, &ms,
 648                     RPC_END);
 649     sscanf (as, "%lx", &atime);
 650     sscanf (ms, "%lx", &mtime);
 651     if (verbose) printf ("Got a = %s, m = %s, comp a = %ld, m = %ld\n",
 652                           as, ms, atime, mtime);
 653     g_free (as);
 654     g_free (ms);
 655     times.actime  = (time_t) atime;
 656     times.modtime = (time_t) mtime;
 657     status = utime (file, &times);
 658     send_status (status, errno);
 659     g_free (file);
 660 }
 661
 662 static void do_quit (void)
 663 {
 664     quit_server = 1;
 665 }
 666
 667 #ifdef HAVE_PAM
 668
 669 struct user_pass {
 670     char *username;
 671     char *password;
 672 };
 673
 674 static int
 675 mc_pam_conversation (int messages, const struct pam_message **msg,
 676                      struct pam_response **resp, void *appdata_ptr)
 677 {
 678     struct pam_response *r;
 679     struct user_pass *up = appdata_ptr;
 680     int status;
 681
 682     r = g_new (struct pam_response, messages);
 683     if (!r)
 684         return PAM_CONV_ERR;
 685     *resp = r;
 686
 687     for (status = PAM_SUCCESS; messages--; msg++, r++){
 688         switch ((*msg)->msg_style){
 689
 690         case PAM_PROMPT_ECHO_ON:
 691             r->resp = g_strdup (up->username);
 692             r->resp_retcode  = PAM_SUCCESS;
 693             break;
 694
 695         case PAM_PROMPT_ECHO_OFF:
 696             r->resp = g_strdup (up->password);
 697             r->resp_retcode = PAM_SUCCESS;
 698             break;
 699
 700         case PAM_ERROR_MSG:
 701             r->resp = NULL;
 702             r->resp_retcode = PAM_SUCCESS;
 703             break;
 704
 705         case PAM_TEXT_INFO:
 706             r->resp = NULL;
 707             r->resp_retcode = PAM_SUCCESS;
 708             break;
 709         }
 710     }
 711     return status;
 712 }
 713
 714 static struct pam_conv conv = { &mc_pam_conversation, NULL };
 715
 716
 717 /* Return 0 if authentication failed, 1 otherwise */
 718 static int
 719 mc_pam_auth (char *username, char *password)
 720 {
 721     pam_handle_t *pamh;
 722     struct user_pass up;
 723     int status;
 724
 725     up.username = username;
 726     up.password = password;
 727     conv.appdata_ptr = &up;
 728
 729     if ((status = pam_start("mcserv", username, &conv, &pamh)) != PAM_SUCCESS)
 730         goto failed_pam;
 731     if ((status = pam_authenticate (pamh, 0)) != PAM_SUCCESS)
 732         goto failed_pam;
 733     if ((status = pam_acct_mgmt (pamh, 0)) != PAM_SUCCESS)
 734         goto failed_pam;
 735     if ((status = pam_setcred (pamh, PAM_ESTABLISH_CRED)) != PAM_SUCCESS)
 736         goto failed_pam;
 737     pam_end (pamh, status);
 738     return 0;
 739
 740 failed_pam:
 741     pam_end (pamh, status);
 742     return 1;
 743 }
 744
 745 #else /* Code for non-PAM authentication */
 746
 747 /* Keep reading until we find a \n */
 748 static int next_line (int socket)
 749 {
 750     char c;
 751
 752     while (1){
 753         if (read (socket, &c, 1) <= 0)
 754             return 0;
 755         if (c == '\n')
 756             return 1;
 757     }
 758 }
 759
 760 static int ftp_answer (int sock, char *text)
 761 {
 762     char answer [4];
 763
 764     next_line (sock);
 765     socket_read_block (sock, answer, 3);
 766     answer [3] = 0;
 767     if (strcmp (answer, text) == 0)
 768         return 1;
 769     return 0;
 770 }
 771
 772 static int do_ftp_auth (char *username, char *password)
 773 {
 774     struct   sockaddr_in local_address;
 775     unsigned long inaddr;
 776     int      my_socket;
 777     char     answer [4];
 778
 779     memset ((char *) &local_address, 0, sizeof (local_address));
 780
 781     local_address.sin_family = AF_INET;
 782     /* FIXME: extract the ftp port with the proper function */
 783     local_address.sin_port   = htons (21);
 784
 785     /*  Convert localhost to usable format */
 786     if ((inaddr = inet_addr ("127.0.0.1")) != -1)
 787         memcpy ((char *) &local_address.sin_addr, (char *) &inaddr,
 788                 sizeof (inaddr));
 789
 790     if ((my_socket = socket (AF_INET, SOCK_STREAM, 0)) < 0){
 791         if (!isDaemon) fprintf (stderr, "do_auth: can't create socket\n");
 792         return 0;
 793     }
 794     if (connect (my_socket, (struct sockaddr *) &local_address,
 795              sizeof (local_address)) < 0){
 796         fprintf (stderr,
 797                  "do_auth: can't connect to ftp daemon for authentication\n");
 798         close (my_socket);
 799         return 0;
 800     }
 801     send_string (my_socket, "user ");
 802     send_string (my_socket, username);
 803     send_string (my_socket, "\r\n");
 804     if (!ftp_answer (my_socket, "331")){
 805         send_string (my_socket, "quit\r\n");
 806         close (my_socket);
 807         return 0;
 808     }
 809     next_line (my_socket);      /* Eat all the line */
 810     send_string (my_socket, "pass ");
 811     send_string (my_socket, password);
 812     send_string (my_socket, "\r\n");
 813     socket_read_block (my_socket, answer, 3);
 814     answer [3] = 0;
 815     send_string (my_socket, "\r\n");
 816     send_string (my_socket, "quit\r\n");
 817     close (my_socket);
 818     if (strcmp (answer, "230") == 0)
 819         return 1;
 820     return 0;
 821 }
 822
 823 static int do_classic_auth (char *username, char *password)
 824 {
 825     struct passwd *this;
 826     int ret;
 827 #ifdef LINUX_SHADOW
 828     struct spwd *spw;
 829     extern char *pw_encrypt (char *, char *);
 830 #else
 831 #ifdef NEED_CRYPT_PROTOTYPE
 832     extern char *crypt (const char *, const char *);
 833 #endif
 834 #endif
 835
 836     if ((this = getpwnam (username)) == 0)
 837         return 0;
 838
 839 #ifdef LINUX_SHADOW
 840     if ((spw = getspnam (username)) == NULL)
 841         this->pw_passwd = "*";
 842     else
 843         this->pw_passwd = spw->sp_pwdp;
 844     if (strcmp (pw_encrypt (password, this->pw_passwd), this->pw_passwd) == 0)
 845         ret = 1;
 846     else
 847         ret = 0;
 848 #else
 849 #ifdef HAVE_CRYPT
 850     if (strcmp (crypt (password, this->pw_passwd), this->pw_passwd) == 0){
 851         ret = 1;
 852     } else
 853 #endif
 854     {
 855         ret = 0;
 856     }
 857 #endif
 858     endpwent ();
 859     return ret;
 860 }
 861 #endif /* non-PAM authentication */
 862
 863 /* Try to authenticate the user based on:
 864    - PAM if the system has it, else it checks:
 865    - pwdauth if the system supports it.
 866    - conventional auth (check salt on /etc/passwd, crypt, and compare
 867    - try to contact the local ftp server and login (if -f flag used)
 868 */
 869 static int
 870 do_auth (char *username, char *password)
 871 {
 872     int auth = 0;
 873     struct passwd *this;
 874
 875     if (strcmp (username, "anonymous") == 0)
 876         username = "ftp";
 877
 878 #ifdef HAVE_PAM
 879     if (mc_pam_auth (username, password) == 0)
 880         auth = 1;
 881 #else /* if there is no pam */
 882 #ifdef HAVE_PWDAUTH
 883     if (pwdauth (username, password) == 0)
 884         auth = 1;
 885     else
 886 #endif
 887     if (do_classic_auth (username, password))
 888         auth = 1;
 889     else if (ftp)
 890         auth = do_ftp_auth (username, password);
 891 #endif /* not pam */
 892
 893     if (!auth)
 894         return 0;
 895
 896     this = getpwnam (username);
 897     if (this == 0)
 898         return 0;
 899
 900     if (chdir (this->pw_dir) == -1)
 901         return 0;
 902
 903     if (this->pw_dir [strlen (this->pw_dir) - 1] == '/')
 904         home_dir = g_strdup (this->pw_dir);
 905     else {
 906         home_dir = g_malloc (strlen (this->pw_dir) + 2);
 907         if (home_dir) {
 908             strcpy (home_dir, this->pw_dir);
 909             strcat (home_dir, "/");
 910         } else
 911             home_dir = "/";
 912     }
 913
 914
 915     if (setgid (this->pw_gid) == -1)
 916         return 0;
 917
 918 #ifdef HAVE_INITGROUPS
 919 #ifdef NGROUPS_MAX
 920     if (NGROUPS_MAX > 1 && initgroups (this->pw_name, this->pw_gid))
 921         return 0;
 922 #endif
 923 #endif
 924
 925 #if defined (HAVE_SETUID)
 926     if (setuid (this->pw_uid))
 927         return 0;
 928 #elif defined (HAVE_SETREUID)
 929     if (setreuid (this->pw_uid, this->pw_uid))
 930         return 0;
 931 #endif
 932
 933     /* If the setuid call failed, then deny access */
 934     /* This should fix the problem on those machines with strange setups */
 935     if (getuid () != this->pw_uid)
 936         return 0;
 937
 938     if (strcmp (username, "ftp") == 0)
 939         chroot (this->pw_dir);
 940
 941     endpwent ();
 942     return auth;
 943 }
 944
 945 #if 0
 946 static int do_rauth (int socket)
 947 {
 948     struct sockaddr_in from;
 949     struct hostent *hp;
 950
 951     if (getpeername(0, (struct sockaddr *)&from, &fromlen) < 0)
 952         return 0;
 953     from.sin_port = ntohs ((unsigned short) from.sin_port);
 954
 955     /* Strange, this should not happend */
 956     if (from.sin_family != AF_INET)
 957         return 0;
 958
 959     hp = gethostbyaddr((char *)&fromp.sin_addr, sizeof (struct in_addr),
 960                        fromp.sin_family);
 961
 962 }
 963 #endif
 964
 965 static int do_rauth (int msock)
 966 {
 967     return 0;
 968 }
 969
 970 static void login_reply (int logged_in)
 971 {
 972     rpc_send (msock, RPC_INT,
 973               logged_in ? MC_LOGINOK : MC_INVALID_PASS,
 974               RPC_END);
 975 }
 976
 977 /* FIXME: Implement the anonymous login */
 978 static void do_login (void)
 979 {
 980     char *username;
 981     char *password;
 982     int  result;
 983
 984     rpc_get (msock, RPC_LIMITED_STRING, &up_dir, RPC_LIMITED_STRING, &username, RPC_END);
 985     if (verbose) printf ("username: %s\n", username);
 986
 987     if (r_auth){
 988         logged_in = do_rauth (msock);
 989         if (logged_in){
 990             login_reply (logged_in);
 991             return;
 992         }
 993     }
 994     rpc_send (msock, RPC_INT, MC_NEED_PASSWORD, RPC_END);
 995     rpc_get (msock, RPC_INT, &result, RPC_END);
 996     if (result == MC_QUIT)
 997         DO_QUIT_VOID ();
 998     if (result != MC_PASS){
 999         if (verbose) printf ("do_login: Unknown response: %d\n", result);
1000         DO_QUIT_VOID ();
1001     }
1002     rpc_get (msock, RPC_LIMITED_STRING, &password, RPC_END);
1003     logged_in = do_auth (username, password);
1004     endpwent ();
1005     login_reply (logged_in);
1006 }
1007
1008 /* }}} */
1009
1010 /* {{{ Server and dispatching functions */
1011
1012 /* This structure must be kept in synch with mcfs.h enums */
1013
1014 static struct _command {
1015     char *command;
1016     void (*callback)(void);
1017 } commands [] = {
1018     { "open",       do_open },
1019     { "close",      do_close },
1020     { "read",       do_read },
1021     { "write",      do_write },
1022     { "opendir",    do_opendir },
1023     { "readdir",    do_readdir },
1024     { "closedir",   do_closedir },
1025     { "stat ",      do_stat },
1026     { "lstat ",     do_lstat },
1027     { "fstat",      do_fstat },
1028     { "chmod",      do_chmod },
1029     { "chown",      do_chown },
1030     { "readlink ",  do_readlink },
1031     { "unlink",     do_unlink },
1032     { "rename",     do_rename },
1033     { "chdir ",     do_chdir },
1034     { "lseek",      do_lseek },
1035     { "rmdir",      do_rmdir },
1036     { "symlink",    do_symlink },
1037     { "mknod",      do_mknod },
1038     { "mkdir",      do_mkdir },
1039     { "link",       do_link },
1040     { "gethome",    do_gethome },
1041     { "getupdir",   do_getupdir },
1042     { "login",      do_login },
1043     { "quit",       do_quit },
1044     { "utime",      do_utime },
1045 };
1046
1047 static int ncommands = sizeof(commands)/sizeof(struct _command);
1048
1049 static void exec_command (int command)
1050 {
1051     if (command < 0 ||
1052         command >= ncommands ||
1053         commands [command].command == 0){
1054         fprintf (stderr, "Got unknown command: %d\n", command);
1055         DO_QUIT_VOID ();
1056     }
1057     if (verbose) printf ("Command: %s\n", commands [command].command);
1058     (*commands [command].callback)();
1059 }
1060
1061 static void check_version (void)
1062 {
1063     int version;
1064
1065     rpc_get (msock, RPC_INT, &version, RPC_END);
1066     if (version >= 1 &&
1067         version <= RPC_PROGVER)
1068         rpc_send (msock, RPC_INT, MC_VERSION_OK, RPC_END);
1069     else
1070         rpc_send (msock, RPC_INT, MC_VERSION_MISMATCH, RPC_END);
1071
1072     clnt_version = version;
1073 }
1074
1075 /* This routine is called by rpc_get/rpc_send when the connection is closed */
1076 void tcp_invalidate_socket (int sock)
1077 {
1078     if (verbose) printf ("Connection closed\n");
1079     DO_QUIT_VOID();
1080 }
1081
1082 static void server (int sock)
1083 {
1084     int command;
1085
1086     msock = sock;
1087     quit_server = 0;
1088
1089     check_version ();
1090     do {
1091         if (rpc_get (sock, RPC_INT, &command, RPC_END) &&
1092             (logged_in || command == MC_LOGIN))
1093             exec_command (command);
1094     } while (!quit_server);
1095 }
1096
1097 /* }}} */
1098
1099 /* {{{ Net support code */
1100
1101 static char *get_client (int portnum)
1102 {
1103     int sock, clilen, newsocket;
1104     struct sockaddr_in client_address, server_address;
1105     struct hostent *hp;
1106     char hostname [255];
1107     int yes = 1;
1108 #ifdef __EMX__
1109     char *me;
1110 #endif
1111
1112     if ((sock = socket (AF_INET, SOCK_STREAM, 0)) < 0)
1113         return "Cannot create socket";
1114
1115     /* Use this to debug: */
1116     if (setsockopt (sock, SOL_SOCKET, SO_REUSEADDR, (char *) &yes, sizeof (yes)) < 0)
1117         return "setsockopt failed";
1118
1119     gethostname (hostname, 255);
1120     if (verbose) printf ("hostname=%s\n", hostname);
1121     hp = gethostbyname (hostname);
1122 #ifdef __EMX__
1123     if (hp == 0 && (me = getenv("HOSTNAME")) && (0 == strcmp(hostname, me)))
1124         hp = gethostbyname ("localhost");
1125 #endif
1126     if (hp == 0)
1127         return "hp = 0!";
1128
1129     memset ((char *) &server_address, 0, sizeof (server_address));
1130     server_address.sin_family = hp->h_addrtype;
1131     server_address.sin_addr.s_addr = htonl (INADDR_ANY);
1132     server_address.sin_port = htons (portnum);
1133
1134     if (bind (sock, (struct sockaddr *) &server_address,
1135               sizeof (server_address)) < 0)
1136         return "Cannot bind";
1137
1138     listen (sock, 5);
1139
1140     for (;;){
1141         int child;
1142
1143         clilen = sizeof (client_address);
1144         newsocket = accept (sock, (struct sockaddr *) &client_address,
1145                             &clilen);
1146
1147         if (isDaemon && (child = fork())) {
1148             int status;
1149
1150             close (newsocket);
1151             waitpid (child, &status, 0);
1152             continue;
1153         }
1154
1155         if (isDaemon && fork()) exit (0);
1156
1157         server (newsocket);
1158         close (newsocket);
1159         return 0;
1160     }
1161 }
1162
1163 #ifdef HAVE_PMAP_SET
1164 static void signal_int_handler (int sig)
1165 {
1166     pmap_unset (RPC_PROGNUM, RPC_PROGVER);
1167 }
1168 #endif
1169
1170 #ifndef IPPORT_RESERVED
1171 #define IPPORT_RESERVED 1024;
1172 #endif
1173
1174 static int get_port_number (void)
1175 {
1176     int port = 0;
1177
1178 #ifdef HAVE_RRESVPORT
1179     int start_port = IPPORT_RESERVED;
1180
1181     port = rresvport (&start_port);
1182     if (port == -1){
1183         if (geteuid () == 0){
1184             fprintf (stderr, "Could not bind the server on a reserved port\n");
1185             DO_QUIT_NONVOID (-1);
1186         }
1187         port = 0;
1188     }
1189 #endif
1190     if (port)
1191         return port;
1192
1193     port = mcserver_port;
1194
1195     return port;
1196 }
1197
1198 static void register_port (int portnum, int abort_if_fail)
1199 {
1200 #ifdef HAVE_PMAP_SET
1201     /* Register our service with the portmapper */
1202     /* protocol: pmap_set (prognum, versnum, protocol, portp) */
1203
1204     if (pmap_set (RPC_PROGNUM, RPC_PROGVER, IPPROTO_TCP, portnum))
1205         signal (SIGINT, signal_int_handler);
1206     else {
1207         fprintf (stderr, "Could not register service with portmapper\n");
1208         if (abort_if_fail)
1209             exit (1);
1210     }
1211 #else
1212     if (abort_if_fail){
1213         fprintf (stderr,
1214                  "This system lacks port registration, try using the -p\n"
1215                  "flag to force installation at a given port");
1216     }
1217 #endif
1218 }
1219
1220 /* }}} */
1221
1222 int main (int argc, char *argv [])
1223 {
1224     char *result;
1225     extern char *optarg;
1226     int c;
1227
1228     while ((c = getopt (argc, argv, "fdiqp:v")) != -1){
1229         switch (c){
1230         case 'd':
1231             isDaemon = 1;
1232             verbose = 0;
1233             break;
1234
1235         case 'v':
1236             verbose = 1;
1237             break;
1238
1239         case 'f':
1240             ftp = 1;
1241             break;
1242
1243         case 'q':
1244             verbose = 0;
1245             break;
1246
1247         case 'p':
1248             portnum = atoi (optarg);
1249             break;
1250
1251         case 'i':
1252             inetd_started = 1;
1253             break;
1254
1255         case 'r':
1256             r_auth = 1;
1257             break;
1258
1259         default:
1260             fprintf (stderr, "Usage is: mcserv [options] [-p portnum]\n\n"
1261                     "options are:\n"
1262                     "-d  become a daemon (sets -q)\n"
1263                     "-q  quiet mode\n"
1264                 /*    "-r  use rhost based authentication\n" */
1265 #ifndef HAVE_PAM
1266                     "-f  force ftp authentication\n"
1267 #endif
1268                     "-v  verbose mode\n"
1269                     "-p  to specify a port number to listen\n");
1270             exit (0);
1271
1272         }
1273     }
1274
1275     if (isDaemon && fork()) exit (0);
1276
1277     if (portnum == 0)
1278         portnum = get_port_number ();
1279
1280     if (portnum != -1) {
1281         register_port (portnum, 0);
1282         if (verbose)
1283             printf ("Using port %d\n", portnum);
1284         if ((result = get_client (portnum)))
1285             perror (result);
1286 #ifdef HAVE_PMAP_SET
1287         if (!isDaemon)
1288             pmap_unset (RPC_PROGNUM, RPC_PROGVER);
1289 #endif
1290     }
1291     exit (return_code);
1292 }
1293
1294 /* FIXME: This function should not be used in mcserv */
1295 void vfs_die( char *m )
1296 {
1297     fputs (m, stderr);
1298     exit (1);
1299 }
1300