source: rtems/cpukit/ftpd/ftpd.c @ 09647b7

4.115
Last change on this file since 09647b7 was 09647b7, checked in by Sebastian Huber <sebastian.huber@…>, on Oct 26, 2011 at 10:32:09 AM

2011-10-26 Sebastian Huber <sebastian.huber@…>

  • ftpd/ftpd.h, ftpd/ftpd.c: Moved buffer and stack size constants into header file.
  • Property mode set to 100644
File size: 50.6 KB
Line 
1/* FIXME: 1. Parse command is a hack.  We can do better.
2 *        2. OSV: hooks support seems to be bad, as it requires storing of
3 *           entire input file in memory.  Seem to be better to change it to
4 *           something more reasonable, like having
5 *           'hook_write(void const *buf, int count)' routine that will be
6 *           called multiple times while file is being received.
7 *        3. OSV: Remove hack with "/dev/null"?
8 *
9 *  FTP Server Daemon
10 *
11 *  Submitted by: Jake Janovetz <janovetz@tempest.ece.uiuc.edu>
12 *
13 *  Changed by:   Sergei Organov <osv@javad.ru> (OSV)
14 *                Arnout Vandecappelle <arnout@mind.be> (AV)
15 *                Sebastien Bourdeauducq <sebastien@milkymist.org> (MM)
16 *               
17 *
18 *  Changes:
19 *
20 *    2010-12-02        Sebastien Bourdeauducq <sebastien@milkymist.org>
21 *
22 *      * Support spaces in filenames
23 *
24 *    2010-04-29        Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
25 *
26 *      * Added USER/PASS authentication.
27 *
28 *    2001-01-31        Sergei Organov <osv@javad.ru>
29 *
30 *      * Hacks with current dir and root dir removed in favor of new libio
31 *        support for task-local current and root directories.
32 *
33 *    2001-01-30        Sergei Organov <osv@javad.ru>
34 *
35 *      * Bug in `close_data_socket()' introduced by previous change fixed.
36 *      * `command_pasv()' changed to set timeout on socket we are listening on
37 *        and code fixed to don't close socket twice on error.
38 *      * `serr()' changed to clear `errno'.
39 *      * `data_socket()' changed to clear `errno' before `bind()'.
40 *      * `session()' changed to clear `errno' before processing session.
41 *
42 *    2001-01-29        Sergei Organov <osv@javad.ru>
43 *
44 *      * `close_data_socket()' fixed to close both active and passive sockets
45 *      * Initialize info->data_socket to -1 in `daemon()'
46 *      * Initialize `fname' to empty string  in `exec_command()'
47 *
48 *    2001-01-22        Sergei Organov <osv@javad.ru>
49 *
50 *      * Timeouts on sockets implemented. 'idle' field added to
51 *        configuration. No timeout by default to keep backward compatibility.
52 *        Note: SITE IDLE command not implemented yet.
53 *      * Basic global access control implemented. 'access' field added to
54 *        configuration. No access limitations by default to keep backward
55 *        compatibility.
56 *
57 *    2001-01-17        Sergei Organov <osv@javad.ru>
58 *
59 *      * Anchor data socket for active mode (using self IP and port 20.)
60 *      * Fixed default data port support (still not tested).
61 *      * Don't allow IP address different from originating host in
62 *        PORT command to improve security.
63 *      * Fixed bug in MDTM command.
64 *      * Check for correctness of parsing of argument in command_port().
65 *      * Fixed squeeze_path() to don't allow names like 'NAME/smth' where
66 *        'NAME' is not a directory.
67 *      * Command parsing a little bit improved: command names are now
68 *        converted to upper-case to be more compatible with RFC (command
69 *        names are not case-sensitive.)
70 *      * Reformat comments so that they have RTEMS look-and-feel.
71 *
72 *    2001-01-16        Sergei Organov <osv@javad.ru>
73 *
74 *      * Fixed DELE, SITE CHMOD, RMD, MKD broken by previous changes
75 *      * True ASCII mode implemented (doesn't work for hooks and /dev/null)
76 *      * Passive mode implemented, PASV command added.
77 *      * Default port for data connection could be used (untested, can't find
78 *        ftp client that doesn't send PORT command)
79 *      * SYST reply changed to UNIX, as former RTEMS isn't registered name.
80 *      * Reply codes reviewed and fixed.
81 *
82 *    2001-01-08        Sergei Organov <osv@javad.ru>
83 *
84 *      * use pool of pre-created threads to handle sessions
85 *      * LIST output now similar to what "/bin/ls -al" would output, thus
86 *        FTP clients could parse it.
87 *      * LIST NAME now works (both for files and directories)
88 *      * keep track of CWD for every session separately
89 *      * ability to specify root directory name in configuration table
90 *      * options sent in commands are ignored, thus LIST -al FILE works
91 *      * added support for NLST, CDUP and MDTM commands
92 *      * buffers are allocated on stack instead of heap where possible
93 *      * drop using of task notepad to pass parameters - use function
94 *        arguments instead
95 *      * various bug-fixes, e.g., use of PF_INET in socket() instead of
96 *        AF_INET, use snprintf() instead of sprintf() everywhere for safety,
97 *        etc.
98 *
99 *  $Id$
100 */
101
102/*************************************************************************
103 *                                 ftpd.c
104 *************************************************************************
105 * Description:
106 *
107 *    This file contains the daemon which services requests that appear
108 *    on the FTP port.  This server is compatible with FTP, but it
109 *    also provides 'hooks' to make it usable in situations where files
110 *    are not used/necessary.  Once the server is started, it runs
111 *    forever.
112 *
113 *
114 *    Organization:
115 *
116 *       The FTP daemon is started upon boot along with a (configurable)
117 *       number of tasks to handle sessions.  It runs all the time and
118 *       waits for connections on the known FTP port (21).  When
119 *       a connection is made, it wakes-up a 'session' task.  That
120 *       session then interacts with the remote host.  When the session
121 *       is complete, the session task goes to sleep.  The daemon still
122 *       runs, however.
123 *
124 *
125 * Supported commands are:
126 *
127 * RETR xxx     - Sends a file from the client.
128 * STOR xxx     - Receives a file from the client.  xxx = filename.
129 * LIST xxx     - Sends a file list to the client.
130 * NLST xxx     - Sends a file list to the client.
131 * USER         - Does nothing.
132 * PASS         - Does nothing.
133 * SYST         - Replies with the system type (`RTEMS').
134 * DELE xxx     - Delete file xxx.
135 * MKD xxx      - Create directory xxx.
136 * RMD xxx      - Remove directory xxx.
137 * PWD          - Print working directory.
138 * CWD xxx      - Change working directory.
139 * CDUP         - Change to upper directory.
140 * SITE CHMOD xxx yyy - Change permissions on file yyy to xxx.
141 * PORT a,b,c,d,x,y   - Setup for a data port to IP address a.b.c.d
142 *                      and port (x*256 + y).
143 * MDTM xxx     - Send file modification date/time to the client.
144 *                xxx = filename.
145 * PASV         - Use passive mode data connection.
146 *
147 *
148 * The public routines contained in this file are:
149 *
150 *    rtems_initialize_ftpd - Initializes and starts the server daemon,
151 *                            then returns to its caller.
152 *
153 *------------------------------------------------------------------------
154 * Jake Janovetz
155 * University of Illinois
156 * 1406 West Green Street
157 * Urbana IL  61801
158 *************************************************************************
159 * Change History:
160 *  12/01/97   - Creation (JWJ)
161 *  2001-01-08 - Changes by OSV
162 *  2010-04-29 - Authentication added by AV
163 *************************************************************************/
164
165/*************************************************************************
166 * Meanings of first and second digits of reply codes:
167 *
168 * Reply:  Description:
169 *-------- --------------
170 *  1yz    Positive preliminary reply.  The action is being started but
171 *         expect another reply before sending another command.
172 *  2yz    Positive completion reply.  A new command can be sent.
173 *  3yz    Positive intermediate reply.  The command has been accepted
174 *         but another command must be sent.
175 *  4yz    Transient negative completion reply.  The requested action did
176 *         not take place, but the error condition is temporary so the
177 *         command can be reissued later.
178 *  5yz    Permanent negative completion reply.  The command was not
179 *         accepted and should not be retried.
180 *-------------------------------------------------------------------------
181 *  x0z    Syntax errors.
182 *  x1z    Information.
183 *  x2z    Connections.  Replies referring to the control or data
184 *         connections.
185 *  x3z    Authentication and accounting.  Replies for the login or
186 *         accounting commands.
187 *  x4z    Unspecified.
188 *  x5z    Filesystem status.
189 *************************************************************************/
190
191#if HAVE_CONFIG_H
192#include "config.h"
193#endif
194
195#include <stdio.h>
196#include <stdlib.h>
197#include <string.h>
198#include <unistd.h>
199#include <fcntl.h>
200#include <dirent.h>
201#include <errno.h>
202#include <ctype.h>
203
204#include <rtems.h>
205#include <rtems/rtems_bsdnet.h>
206#include <rtems/error.h>
207#include <rtems/libio.h>
208#include <rtems/userenv.h>
209#include <syslog.h>
210
211#include <sys/types.h>
212#include <sys/socket.h>
213#include <arpa/ftp.h>
214#include <netinet/in.h>
215
216#include "ftpd.h"
217
218
219#ifdef __GNUC__
220/* change to #if 1 to disable syslog entirely */
221#if 0
222#undef  syslog
223#define syslog(a, b, ...) while(0){}
224#endif
225#endif
226
227#define FTPD_SERVER_MESSAGE  "RTEMS FTP server (Version 1.1-JWJ) ready."
228
229#define FTPD_SYSTYPE "UNIX Type: L8"
230
231/* Seem to be unused */
232#if 0
233#define FTPD_WELCOME_MESSAGE \
234   "Welcome to the RTEMS FTP server.\n" \
235   "\n" \
236   "Login accepted.\n"
237#endif
238
239/* Event to be used by session tasks for waiting */
240enum
241{
242  FTPD_RTEMS_EVENT = RTEMS_EVENT_1
243};
244
245/* Configuration table */
246extern struct rtems_ftpd_configuration rtems_ftpd_configuration;
247
248/* this is not prototyped in strict ansi mode */
249FILE *fdopen (int fildes, const char *mode);
250
251/*SessionInfo structure.
252 *
253 * The following structure is allocated for each session.
254 */
255typedef struct
256{
257  struct sockaddr_in  ctrl_addr;   /* Control connection self address */
258  struct sockaddr_in  data_addr;   /* Data address set by PORT command */
259  struct sockaddr_in  def_addr;    /* Default address for data */
260  int                 use_default; /* 1 - use default address for data */
261  FILE                *ctrl_fp;    /* File pointer for control connection */
262  int                 ctrl_socket; /* Socket for ctrl connection */
263  int                 pasv_socket; /* Socket for PASV connection */
264  int                 data_socket; /* Socket for data connection */
265  int                 idle;        /* Timeout in seconds */
266  int                 xfer_mode;   /* Transfer mode (ASCII/binary) */
267  rtems_id            tid;         /* Task id */
268  char                *user;       /* user name (0 if not supplied) */
269  char                *pass;       /* password (0 if not supplied) */
270  bool                auth;        /* true if user/pass was valid, false if not or not supplied */
271} FTPD_SessionInfo_t;
272
273
274/*
275 * TaskPool structure.
276 */
277typedef struct
278{
279  FTPD_SessionInfo_t    *info;
280  FTPD_SessionInfo_t    **queue;
281  int                   count;
282  int                   head;
283  int                   tail;
284  rtems_id              mutex;
285  rtems_id              sem;
286} FTPD_TaskPool_t;
287
288/*
289 * Task pool instance.
290 */
291static FTPD_TaskPool_t task_pool;
292
293/*
294 * Root directory
295 */
296
297static char const* ftpd_root = "/";
298
299/*
300 * Default idle timeout for sockets in seconds.
301 */
302static int ftpd_timeout = 0;
303
304/*
305 * Global access flags.
306 */
307static int ftpd_access = 0;
308
309/*
310 * serr
311 *
312 * Return error string corresponding to current 'errno'.
313 *
314 */
315static char const*
316serr(void)
317{
318  int err = errno;
319  errno = 0;
320  return strerror(err);
321}
322
323/*
324 * Utility routines for access control.
325 *
326 */
327
328static int
329can_read(void)
330{
331  return (ftpd_access & FTPD_NO_READ) == 0;
332}
333
334static int
335can_write(void)
336{
337  return (ftpd_access & FTPD_NO_WRITE) == 0;
338}
339
340/*
341 * Task pool management routines
342 *
343 */
344
345
346/*
347 * task_pool_done
348 *
349 * Cleanup task pool.
350 *
351 * Input parameters:
352 *   count - number of entries in task pool to cleanup
353 *
354 * Output parameters:
355 *   NONE
356 *
357 */
358static void
359task_pool_done(int count)
360{
361  int i;
362  for(i = 0; i < count; ++i)
363    rtems_task_delete(task_pool.info[i].tid);
364  if(task_pool.info)
365    free(task_pool.info);
366  if(task_pool.queue)
367    free(task_pool.queue);
368  if(task_pool.mutex != (rtems_id)-1)
369    rtems_semaphore_delete(task_pool.mutex);
370  if(task_pool.sem != (rtems_id)-1)
371    rtems_semaphore_delete(task_pool.sem);
372  task_pool.info = 0;
373  task_pool.queue = 0;
374  task_pool.count = 0;
375  task_pool.sem = -1;
376  task_pool.mutex = -1;
377}
378
379/*
380 * task_pool_init
381 *
382 * Initialize task pool.
383 *
384 * Input parameters:
385 *   count    - number of entries in task pool to create
386 *   priority - priority tasks are started with
387 *
388 * Output parameters:
389 *   returns 1 on success, 0 on failure.
390 *
391 */
392static void session(rtems_task_argument arg); /* Forward declare */
393
394static int
395task_pool_init(int count, rtems_task_priority priority)
396{
397  int i;
398  rtems_status_code sc;
399  char id = 'a';
400
401  task_pool.count = 0;
402  task_pool.head = task_pool.tail = 0;
403  task_pool.mutex = (rtems_id)-1;
404  task_pool.sem   = (rtems_id)-1;
405
406  sc = rtems_semaphore_create(
407    rtems_build_name('F', 'T', 'P', 'M'),
408    1,
409    RTEMS_DEFAULT_ATTRIBUTES
410    | RTEMS_BINARY_SEMAPHORE
411    | RTEMS_INHERIT_PRIORITY
412    | RTEMS_PRIORITY,
413    RTEMS_NO_PRIORITY,
414    &task_pool.mutex);
415
416  if(sc == RTEMS_SUCCESSFUL)
417    sc = rtems_semaphore_create(
418      rtems_build_name('F', 'T', 'P', 'S'),
419      count,
420      RTEMS_DEFAULT_ATTRIBUTES,
421      RTEMS_NO_PRIORITY,
422      &task_pool.sem);
423
424  if(sc != RTEMS_SUCCESSFUL) {
425    task_pool_done(0);
426    syslog(LOG_ERR, "ftpd: Can not create semaphores");
427    return 0;
428  }
429
430  task_pool.info = (FTPD_SessionInfo_t*)
431    malloc(sizeof(FTPD_SessionInfo_t) * count);
432  task_pool.queue = (FTPD_SessionInfo_t**)
433    malloc(sizeof(FTPD_SessionInfo_t*) * count);
434  if (NULL == task_pool.info || NULL == task_pool.queue)
435  {
436    task_pool_done(0);
437    syslog(LOG_ERR, "ftpd: Not enough memory");
438    return 0;
439  }
440
441  for(i = 0; i < count; ++i)
442  {
443    FTPD_SessionInfo_t *info = &task_pool.info[i];
444    sc = rtems_task_create(rtems_build_name('F', 'T', 'P', id),
445      priority, FTPD_STACKSIZE,
446      RTEMS_PREEMPT | RTEMS_NO_TIMESLICE |
447      RTEMS_NO_ASR | RTEMS_INTERRUPT_LEVEL(0),
448      RTEMS_NO_FLOATING_POINT | RTEMS_LOCAL,
449      &info->tid);
450    if (sc == RTEMS_SUCCESSFUL)
451    {
452      sc = rtems_task_start(
453        info->tid, session, (rtems_task_argument)info);
454      if (sc != RTEMS_SUCCESSFUL)
455        task_pool_done(i);
456    }
457    else
458      task_pool_done(i + 1);
459    if (sc != RTEMS_SUCCESSFUL)
460    {
461      syslog(LOG_ERR, "ftpd: Could not create/start FTPD session: %s",
462        rtems_status_text(sc));
463      return 0;
464    }
465    task_pool.queue[i] = task_pool.info + i;
466    if (++id > 'z')
467      id = 'a';
468  }
469  task_pool.count = count;
470  return 1;
471}
472
473/*
474 * task_pool_obtain
475 *
476 * Obtain free task from task pool.
477 *
478 * Input parameters:
479 *   NONE
480 *
481 * Output parameters:
482 *   returns pointer to the corresponding SessionInfo structure on success,
483 *           NULL if there are no free tasks in the pool.
484 *
485 */
486static FTPD_SessionInfo_t*
487task_pool_obtain(void)
488{
489  FTPD_SessionInfo_t* info = 0;
490  rtems_status_code sc;
491  sc = rtems_semaphore_obtain(task_pool.sem, RTEMS_NO_WAIT, RTEMS_NO_TIMEOUT);
492  if (sc == RTEMS_SUCCESSFUL)
493  {
494    rtems_semaphore_obtain(task_pool.mutex, RTEMS_WAIT, RTEMS_NO_TIMEOUT);
495    info = task_pool.queue[task_pool.head];
496    if(++task_pool.head >= task_pool.count)
497      task_pool.head = 0;
498    rtems_semaphore_release(task_pool.mutex);
499  }
500  return info;
501}
502
503/*
504 * task_pool_release
505 *
506 * Return task obtained by 'obtain()' back to the task pool.
507 *
508 * Input parameters:
509 *   info  - pointer to corresponding SessionInfo structure.
510 *
511 * Output parameters:
512 *   NONE
513 *
514 */
515static void
516task_pool_release(FTPD_SessionInfo_t* info)
517{
518  rtems_semaphore_obtain(task_pool.mutex, RTEMS_WAIT, RTEMS_NO_TIMEOUT);
519  task_pool.queue[task_pool.tail] = info;
520  if(++task_pool.tail >= task_pool.count)
521    task_pool.tail = 0;
522  rtems_semaphore_release(task_pool.mutex);
523  rtems_semaphore_release(task_pool.sem);
524}
525
526/*
527 * End of task pool routines
528 */
529
530/*
531 * Function: send_reply
532 *
533 *
534 *    This procedure sends a reply to the client via the control
535 *    connection.
536 *
537 *
538 * Input parameters:
539 *   code  - 3-digit reply code.
540 *   text  - Reply text.
541 *
542 * Output parameters:
543 *   NONE
544 */
545static void
546send_reply(FTPD_SessionInfo_t  *info, int code, char *text)
547{
548  text = text != NULL ? text : "";
549  fprintf(info->ctrl_fp, "%d %.70s\r\n", code, text);
550  fflush(info->ctrl_fp);
551}
552
553
554/*
555 * close_socket
556 *
557 * Close socket.
558 *
559 * Input parameters:
560 *   s - socket descriptor.
561 *   seconds - number of seconds the timeout should be,
562 *             if >= 0 - infinite timeout (no timeout).
563 *
564 * Output parameters:
565 *   returns 1 on success, 0 on failure.
566 */
567static int
568set_socket_timeout(int s, int seconds)
569{
570  int res = 0;
571  struct timeval tv;
572  int len = sizeof(tv);
573
574  if(seconds < 0)
575    seconds = 0;
576  tv.tv_usec = 0;
577  tv.tv_sec  = seconds;
578  if(0 != setsockopt(s, SOL_SOCKET, SO_SNDTIMEO, &tv, len))
579    syslog(LOG_ERR, "ftpd: Can't set send timeout on socket: %s.", serr());
580  else if(0 != setsockopt(s, SOL_SOCKET, SO_RCVTIMEO, &tv, len))
581    syslog(LOG_ERR, "ftpd: Can't set receive timeout on socket: %s.", serr());
582  else
583    res = 1;
584  return res;
585}
586
587/*
588 * close_socket
589 *
590 * Close socket.
591 *
592 * Input parameters:
593 *   s - socket descriptor to be closed.
594 *
595 * Output parameters:
596 *   returns 1 on success, 0 on failure
597 */
598static int
599close_socket(int s)
600{
601  if (0 <= s)
602  {
603    if (0 != close(s))
604    {
605      shutdown(s, 2);
606      if (0 != close(s))
607        return 0;
608    }
609  }
610  return 1;
611}
612
613/*
614 * data_socket
615 *
616 * Create data socket for session.
617 *
618 * Input parameters:
619 *   info - corresponding SessionInfo structure
620 *
621 * Output parameters:
622 *   returns socket descriptor, or -1 if failure
623 *
624 */
625static int
626data_socket(FTPD_SessionInfo_t *info)
627{
628  int s = info->pasv_socket;
629  if(0 > s)
630  {
631    int on = 1;
632    s = socket(PF_INET, SOCK_STREAM, 0);
633    if(0 > s)
634      send_reply(info, 425, "Can't create data socket.");
635    else if(0 > setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)))
636    {
637      close_socket(s);
638      s = -1;
639    }
640    else
641    {
642      struct sockaddr_in data_source;
643      int tries;
644
645      /* anchor socket to avoid multi-homing problems */
646      data_source = info->ctrl_addr;
647      data_source.sin_port = htons(20); /* ftp-data port */
648      for(tries = 1; tries < 10; ++tries)
649      {
650        errno = 0;
651        if(bind(s, (struct sockaddr *)&data_source, sizeof(data_source)) >= 0)
652          break;
653        if (errno != EADDRINUSE)
654          tries = 10;
655        else
656          rtems_task_wake_after(tries * 10);
657      }
658      if(tries >= 10)
659      {
660        send_reply(info, 425, "Can't bind data socket.");
661        close_socket(s);
662        s = -1;
663      }
664      else
665      {
666        struct sockaddr_in *data_dest =
667          (info->use_default) ? &info->def_addr : &info->data_addr;
668        if(0 > connect(s, (struct sockaddr *)data_dest, sizeof(*data_dest)))
669        {
670          send_reply(info, 425, "Can't connect data socket.");
671          close_socket(s);
672          s = -1;
673        }
674      }
675    }
676  }
677  info->data_socket = s;
678  info->use_default = 1;
679  if(s >= 0)
680    set_socket_timeout(s, info->idle);
681  return s;
682}
683
684/*
685 * close_data_socket
686 *
687 * Close data socket for session.
688 *
689 * Input parameters:
690 *   info - corresponding SessionInfo structure
691 *
692 * Output parameters:
693 *   NONE
694 *
695 */
696static void
697close_data_socket(FTPD_SessionInfo_t *info)
698{
699  /* As at most one data socket could be open simultaneously and in some cases
700     data_socket == pasv_socket, we select socket to close, then close it. */
701  int s = info->data_socket;
702  if(0 > s)
703    s = info->pasv_socket;
704  if(!close_socket(s))
705    syslog(LOG_ERR, "ftpd: Error closing data socket.");
706  info->data_socket = -1;
707  info->pasv_socket = -1;
708  info->use_default = 1;
709}
710
711/*
712 * close_stream
713 *
714 * Close control stream of session.
715 *
716 * Input parameters:
717 *   info - corresponding SessionInfo structure
718 *
719 * Output parameters:
720 *   NONE
721 *
722 */
723static void
724close_stream(FTPD_SessionInfo_t* info)
725{
726  if (NULL != info->ctrl_fp)
727  {
728    if (0 != fclose(info->ctrl_fp))
729    {
730      syslog(LOG_ERR, "ftpd: Could not close control stream: %s", serr());
731    }
732    else
733      info->ctrl_socket = -1;
734  }
735
736  if (!close_socket(info->ctrl_socket))
737    syslog(LOG_ERR, "ftpd: Could not close control socket: %s", serr());
738
739  info->ctrl_fp = NULL;
740  info->ctrl_socket = -1;
741}
742
743
744/*
745 * send_mode_reply
746 *
747 * Sends BINARY/ASCII reply string depending on current transfer mode.
748 *
749 * Input parameters:
750 *   info - corresponding SessionInfo structure
751 *
752 * Output parameters:
753 *   NONE
754 *
755 */
756static void
757send_mode_reply(FTPD_SessionInfo_t *info)
758{
759  if(info->xfer_mode == TYPE_I)
760    send_reply(info, 150, "Opening BINARY mode data connection.");
761  else
762    send_reply(info, 150, "Opening ASCII mode data connection.");
763}
764
765/*
766 * command_retrieve
767 *
768 * Perform the "RETR" command (send file to client).
769 *
770 * Input parameters:
771 *   info - corresponding SessionInfo structure
772 *   char *filename  - source filename.
773 *
774 * Output parameters:
775 *   NONE
776 *
777 */
778static void
779command_retrieve(FTPD_SessionInfo_t  *info, char const *filename)
780{
781  int                 s = -1;
782  int                 fd = -1;
783  char                buf[FTPD_DATASIZE];
784  struct stat         stat_buf;
785  int                 res = 0;
786
787  if(!can_read() || !info->auth)
788  {
789    send_reply(info, 550, "Access denied.");
790    return;
791  }
792
793  if (0 > (fd = open(filename, O_RDONLY)))
794  {
795    send_reply(info, 550, "Error opening file.");
796    return;
797  }
798
799  if (fstat(fd, &stat_buf) == 0 && S_ISDIR(stat_buf.st_mode))
800  {
801    if (-1 != fd)
802      close(fd);
803    send_reply(info, 550, "Is a directory.");
804    return;
805  }
806
807  send_mode_reply(info);
808
809  s = data_socket(info);
810
811  if (0 <= s)
812  {
813    int n = -1;
814
815    if(info->xfer_mode == TYPE_I)
816    {
817      while ((n = read(fd, buf, FTPD_DATASIZE)) > 0)
818      {
819        if(send(s, buf, n, 0) != n)
820          break;
821      }
822    }
823    else if (info->xfer_mode == TYPE_A)
824    {
825      int rest = 0;
826      while (rest == 0 && (n = read(fd, buf, FTPD_DATASIZE)) > 0)
827      {
828        char const* e = buf;
829        char const* b;
830        int i;
831        rest = n;
832        do
833        {
834          char lf = '\0';
835
836          b = e;
837          for(i = 0; i < rest; ++i, ++e)
838          {
839            if(*e == '\n')
840            {
841              lf = '\n';
842              break;
843            }
844          }
845          if(send(s, b, i, 0) != i)
846            break;
847          if(lf == '\n')
848          {
849            if(send(s, "\r\n", 2, 0) != 2)
850              break;
851            ++e;
852            ++i;
853          }
854        }
855        while((rest -= i) > 0);
856      }
857    }
858
859    if (0 == n)
860    {
861      if (0 == close(fd))
862      {
863        fd = -1;
864        res = 1;
865      }
866    }
867  }
868
869  if (-1 != fd)
870    close(fd);
871
872  if (0 == res)
873    send_reply(info, 451, "File read error.");
874  else
875    send_reply(info, 226, "Transfer complete.");
876
877  close_data_socket(info);
878
879  return;
880}
881
882
883/*
884 * discard
885 *
886 * Analog of `write' routine that just discards passed data
887 *
888 * Input parameters:
889 *   fd    - file descriptor (ignored)
890 *   buf   - data to write (ignored)
891 *   count - number of bytes in `buf'
892 *
893 * Output parameters:
894 *   returns `count'
895 *
896 */
897static ssize_t
898discard(int fd, void const* buf, size_t count)
899{
900  (void)fd;
901  (void)buf;
902  return count;
903}
904
905/*
906 * command_store
907 *
908 * Performs the "STOR" command (receive data from client).
909 *
910 * Input parameters:
911 *   info - corresponding SessionInfo structure
912 *   char *filename   - Destination filename.
913 *
914 * Output parameters:
915 *   NONE
916 */
917static void
918command_store(FTPD_SessionInfo_t *info, char const *filename)
919{
920  int                    s;
921  int                    n;
922  unsigned long          size = 0;
923  struct rtems_ftpd_hook *usehook = NULL;
924  char                   buf[FTPD_DATASIZE];
925  int                    res = 1;
926  int                    bare_lfs = 0;
927  int                    null = 0;
928  typedef ssize_t (*WriteProc)(int, void const*, size_t);
929  WriteProc              wrt = &write;
930
931  if(!can_write() || !info->auth)
932  {
933    send_reply(info, 550, "Access denied.");
934    return;
935  }
936
937  send_mode_reply(info);
938
939  s = data_socket(info);
940  if(0 > s)
941    return;
942
943  null = !strcmp("/dev/null", filename);
944  if (null)
945  {
946    /* File "/dev/null" just throws data away.
947     *  FIXME: this is hack.  Using `/dev/null' filesystem entry would be
948     *  better.
949     */
950    wrt = &discard;
951  }
952
953  if (!null && rtems_ftpd_configuration.hooks != NULL)
954  {
955
956    /* Search our list of hooks to see if we need to do something special. */
957    struct rtems_ftpd_hook *hook;
958    int i;
959
960    i = 0;
961    hook = &rtems_ftpd_configuration.hooks[i++];
962    while (hook->filename != NULL)
963    {
964      if (!strcmp(hook->filename, filename))
965      {
966        usehook = hook;
967        break;
968      }
969      hook = &rtems_ftpd_configuration.hooks[i++];
970    }
971  }
972
973  if (usehook != NULL)
974  {
975    /*
976     * OSV: FIXME: Small buffer could be used and hook routine
977     * called multiple times instead.  Alternatively, the support could be
978     * removed entirely in favor of configuring RTEMS pseudo-device with
979     * given name.
980     */
981
982    char                *bigBufr;
983    size_t filesize = rtems_ftpd_configuration.max_hook_filesize + 1;
984
985    /*
986     * Allocate space for our "file".
987     */
988    bigBufr = (char *)malloc(filesize);
989    if (bigBufr == NULL)
990    {
991      send_reply(info, 451, "Local resource failure: malloc.");
992      close_data_socket(info);
993      return;
994    }
995
996    /*
997     * Retrieve the file into our buffer space.
998     */
999    size = 0;
1000    while ((n = recv(s, bigBufr + size, filesize - size, 0)) > 0)
1001    {
1002      size += n;
1003    }
1004    if (size >= filesize)
1005    {
1006      send_reply(info, 451, "File too long: buffer size exceeded.");
1007      free(bigBufr);
1008      close_data_socket(info);
1009      return;
1010    }
1011
1012    /*
1013     * Call our hook.
1014     */
1015    res = (usehook->hook_function)(bigBufr, size) == 0;
1016    free(bigBufr);
1017    if(!res)
1018    {
1019      send_reply(info, 451, "File processing failed.");
1020      close_data_socket(info);
1021      return;
1022    }
1023  }
1024  else
1025  {
1026    /* Data transfer to regular file or /dev/null. */
1027    int fd = 0;
1028
1029    if(!null)
1030      fd = creat(filename,
1031        S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
1032
1033    if (0 > fd)
1034    {
1035      send_reply(info, 550, "Error creating file.");
1036      close_data_socket(info);
1037      return;
1038    }
1039
1040    if(info->xfer_mode == TYPE_I)
1041    {
1042      while ((n = recv(s, buf, FTPD_DATASIZE, 0)) > 0)
1043      {
1044        if (wrt(fd, buf, n) != n)
1045        {
1046          res = 0;
1047          break;
1048        }
1049      }
1050    }
1051    else if(info->xfer_mode == TYPE_A)
1052    {
1053      int rest = 0;
1054      int pended_cr = 0;
1055      while (res && rest == 0 && (n = recv(s, buf, FTPD_DATASIZE, 0)) > 0)
1056      {
1057        char const* e = buf;
1058        char const* b;
1059        int i;
1060
1061        rest = n;
1062        if(pended_cr && *e != '\n')
1063        {
1064          char const lf = '\r';
1065          pended_cr = 0;
1066          if(wrt(fd, &lf, 1) != 1)
1067          {
1068            res = 0;
1069            break;
1070          }
1071        }
1072        do
1073        {
1074          int count;
1075          int sub = 0;
1076
1077          b = e;
1078          for(i = 0; i < rest; ++i, ++e)
1079          {
1080            int pcr = pended_cr;
1081            pended_cr = 0;
1082            if(*e == '\r')
1083            {
1084              pended_cr = 1;
1085            }
1086            else if(*e == '\n')
1087            {
1088              if(pcr)
1089              {
1090                sub = 2;
1091                ++i;
1092                ++e;
1093                break;
1094              }
1095              ++bare_lfs;
1096            }
1097          }
1098          if(res == 0)
1099            break;
1100          count = i - sub - pended_cr;
1101          if(count > 0 && wrt(fd, b, count) != count)
1102          {
1103            res = 0;
1104            break;
1105          }
1106          if(sub == 2 && wrt(fd, e - 1, 1) != 1)
1107            res = 0;
1108        }
1109        while((rest -= i) > 0);
1110      }
1111    }
1112
1113    if (0 > close(fd) || res == 0)
1114    {
1115      send_reply(info, 452, "Error writing file.");
1116      close_data_socket(info);
1117      return;
1118    }
1119  }
1120
1121  if (bare_lfs > 0)
1122  {
1123    snprintf(buf, FTPD_BUFSIZE,
1124      "Transfer complete. WARNING! %d bare linefeeds received in ASCII mode.",
1125      bare_lfs);
1126    send_reply(info, 226, buf);
1127  }
1128  else
1129    send_reply(info, 226, "Transfer complete.");
1130  close_data_socket(info);
1131
1132}
1133
1134
1135/*
1136 * send_dirline
1137 *
1138 * Sends one line of LIST command reply corresponding to single file.
1139 *
1140 * Input parameters:
1141 *   s - socket descriptor to send data to
1142 *   wide - if 0, send only file name.  If not 0, send 'stat' info as well in
1143 *          "ls -l" format.
1144 *   curTime - current time
1145 *   path - path to be prepended to what is given by 'add'
1146 *   add  - path to be appended to what is given by 'path', the resulting path
1147 *          is then passed to 'stat()' routine
1148 *   name - file name to be reported in output
1149 *   buf  - buffer for temporary data
1150 *
1151 * Output parameters:
1152 *   returns 0 on failure, 1 on success
1153 *
1154 */
1155static int
1156send_dirline(int s, int wide, time_t curTime, char const* path,
1157  char const* add, char const* fname, char* buf)
1158{
1159  if(wide)
1160  {
1161    struct stat stat_buf;
1162
1163    int plen = strlen(path);
1164    int alen = strlen(add);
1165    if(plen == 0)
1166    {
1167      buf[plen++] = '/';
1168      buf[plen] = '\0';
1169    }
1170    else
1171    {
1172      strcpy(buf, path);
1173      if(alen > 0 && buf[plen - 1] != '/')
1174      {
1175        buf[plen++] = '/';
1176        if(plen >= FTPD_BUFSIZE)
1177          return 0;
1178        buf[plen] = '\0';
1179      }
1180    }
1181    if(plen + alen >= FTPD_BUFSIZE)
1182      return 0;
1183    strcpy(buf + plen, add);
1184
1185    if (stat(buf, &stat_buf) == 0)
1186    {
1187      int len;
1188      struct tm bt;
1189      time_t tf = stat_buf.st_mtime;
1190      enum { SIZE = 80 };
1191      time_t SIX_MONTHS = (365L*24L*60L*60L)/2L;
1192      char timeBuf[SIZE];
1193      gmtime_r(&tf, &bt);
1194      if(curTime > tf + SIX_MONTHS || tf > curTime + SIX_MONTHS)
1195        strftime (timeBuf, SIZE, "%b %d  %Y", &bt);
1196      else
1197        strftime (timeBuf, SIZE, "%b %d %H:%M", &bt);
1198
1199      len = snprintf(buf, FTPD_BUFSIZE,
1200        "%c%c%c%c%c%c%c%c%c%c  1 %5d %5d %11u %s %s\r\n",
1201        (S_ISLNK(stat_buf.st_mode)?('l'):
1202          (S_ISDIR(stat_buf.st_mode)?('d'):('-'))),
1203        (stat_buf.st_mode & S_IRUSR)?('r'):('-'),
1204        (stat_buf.st_mode & S_IWUSR)?('w'):('-'),
1205        (stat_buf.st_mode & S_IXUSR)?('x'):('-'),
1206        (stat_buf.st_mode & S_IRGRP)?('r'):('-'),
1207        (stat_buf.st_mode & S_IWGRP)?('w'):('-'),
1208        (stat_buf.st_mode & S_IXGRP)?('x'):('-'),
1209        (stat_buf.st_mode & S_IROTH)?('r'):('-'),
1210        (stat_buf.st_mode & S_IWOTH)?('w'):('-'),
1211        (stat_buf.st_mode & S_IXOTH)?('x'):('-'),
1212        (int)stat_buf.st_uid,
1213        (int)stat_buf.st_gid,
1214        (int)stat_buf.st_size,
1215        timeBuf,
1216        fname
1217      );
1218
1219      if(send(s, buf, len, 0) != len)
1220        return 0;
1221    }
1222  }
1223  else
1224  {
1225    int len = snprintf(buf, FTPD_BUFSIZE, "%s\r\n", fname);
1226    if(send(s, buf, len, 0) != len)
1227      return 0;
1228  }
1229  return 1;
1230}
1231
1232/*
1233 * command_list
1234 *
1235 * Send file list to client.
1236 *
1237 * Input parameters:
1238 *   info - corresponding SessionInfo structure
1239 *   char *fname  - File (or directory) to list.
1240 *
1241 * Output parameters:
1242 *   NONE
1243 */
1244static void
1245command_list(FTPD_SessionInfo_t *info, char const *fname, int wide)
1246{
1247  int                 s;
1248  DIR                 *dirp = 0;
1249  struct dirent       *dp = 0;
1250  struct stat         stat_buf;
1251  char                buf[FTPD_BUFSIZE];
1252  time_t curTime;
1253  int sc = 1;
1254
1255  if(!info->auth)
1256  {
1257    send_reply(info, 550, "Access denied.");
1258    return;
1259  }
1260
1261  send_reply(info, 150, "Opening ASCII mode data connection for LIST.");
1262
1263  s = data_socket(info);
1264  if(0 > s)
1265  {
1266    syslog(LOG_ERR, "ftpd: Error connecting to data socket.");
1267    return;
1268  }
1269
1270  if(fname[0] == '\0')
1271    fname = ".";
1272
1273  if (0 > stat(fname, &stat_buf))
1274  {
1275    snprintf(buf, FTPD_BUFSIZE,
1276      "%s: No such file or directory.\r\n", fname);
1277    send(s, buf, strlen(buf), 0);
1278  }
1279  else if (S_ISDIR(stat_buf.st_mode) && (NULL == (dirp = opendir(fname))))
1280  {
1281    snprintf(buf, FTPD_BUFSIZE,
1282      "%s: Can not open directory.\r\n", fname);
1283    send(s, buf, strlen(buf), 0);
1284  }
1285  else
1286  {
1287    time(&curTime);
1288    if(!dirp && *fname)
1289      sc = sc && send_dirline(s, wide, curTime, fname, "", fname, buf);
1290    else {
1291      /* FIXME: need "." and ".." only when '-a' option is given */
1292      sc = sc && send_dirline(s, wide, curTime, fname, "", ".", buf);
1293      sc = sc && send_dirline(s, wide, curTime, fname,
1294        (strcmp(fname, ftpd_root) ? ".." : ""), "..", buf);
1295      while (sc && (dp = readdir(dirp)) != NULL)
1296        sc = sc &&
1297          send_dirline(s, wide, curTime, fname, dp->d_name, dp->d_name, buf);
1298    }
1299  }
1300
1301  if(dirp)
1302    closedir(dirp);
1303  close_data_socket(info);
1304
1305  if(sc)
1306    send_reply(info, 226, "Transfer complete.");
1307  else
1308    send_reply(info, 426, "Connection aborted.");
1309}
1310
1311
1312/*
1313 * command_cwd
1314 *
1315 * Change current working directory.
1316 *
1317 * Input parameters:
1318 *   info - corresponding SessionInfo structure
1319 *   dir  - directory name passed in CWD command
1320 *
1321 * Output parameters:
1322 *   NONE
1323 *
1324 */
1325static void
1326command_cwd(FTPD_SessionInfo_t  *info, char *dir)
1327{
1328  if(!info->auth)
1329  {
1330    send_reply(info, 550, "Access denied.");
1331    return;
1332  }
1333
1334  if(chdir(dir) == 0)
1335    send_reply(info, 250, "CWD command successful.");
1336  else
1337    send_reply(info, 550, "CWD command failed.");
1338}
1339
1340
1341/*
1342 * command_pwd
1343 *
1344 * Send current working directory to client.
1345 *
1346 * Input parameters:
1347 *   info - corresponding SessionInfo structure
1348 *
1349 * Output parameters:
1350 *   NONE
1351 */
1352static void
1353command_pwd(FTPD_SessionInfo_t  *info)
1354{
1355  char buf[FTPD_BUFSIZE];
1356  char const* cwd;
1357  errno = 0;
1358  buf[0] = '"';
1359
1360  if(!info->auth)
1361  {
1362    send_reply(info, 550, "Access denied.");
1363    return;
1364  }
1365
1366  cwd = getcwd(buf + 1, FTPD_BUFSIZE - 4);
1367  if(cwd)
1368  {
1369    int len = strlen(cwd);
1370    static char const txt[] = "\" is the current directory.";
1371    int size = sizeof(txt);
1372    if(len + size + 1 >= FTPD_BUFSIZE)
1373      size = FTPD_BUFSIZE - len - 2;
1374    memcpy(buf + len + 1, txt, size);
1375    buf[len + size] = '\0';
1376    send_reply(info, 250, buf);
1377  }
1378  else {
1379    snprintf(buf, FTPD_BUFSIZE, "Error: %s.", serr());
1380    send_reply(info, 452, buf);
1381  }
1382}
1383
1384/*
1385 * command_mdtm
1386 *
1387 * Handle FTP MDTM command (send file modification time to client)/
1388 *
1389 * Input parameters:
1390 *   info - corresponding SessionInfo structure
1391 *   fname - file name passed in MDTM command
1392 *
1393 * Output parameters:
1394 *   info->cwd is set to new CWD value.
1395 */
1396static void
1397command_mdtm(FTPD_SessionInfo_t  *info, char const* fname)
1398{
1399  struct stat stbuf;
1400  char buf[FTPD_BUFSIZE];
1401
1402  if(!info->auth)
1403  {
1404    send_reply(info, 550, "Access denied.");
1405    return;
1406  }
1407
1408  if (0 > stat(fname, &stbuf))
1409  {
1410    snprintf(buf, FTPD_BUFSIZE, "%s: %s.", fname, serr());
1411    send_reply(info, 550, buf);
1412  }
1413  else
1414  {
1415    struct tm *t = gmtime(&stbuf.st_mtime);
1416    snprintf(buf, FTPD_BUFSIZE, "%04d%02d%02d%02d%02d%02d",
1417      1900 + t->tm_year,
1418      t->tm_mon+1, t->tm_mday,
1419      t->tm_hour, t->tm_min, t->tm_sec);
1420    send_reply(info, 213, buf);
1421  }
1422}
1423
1424/*
1425 * command_port
1426 *
1427 * This procedure fills address for data connection given the IP address and
1428 * port of the remote machine.
1429 *
1430 * Input parameters:
1431 *   info - corresponding SessionInfo structure
1432 *   args - arguments to the "PORT" command.
1433 *
1434 * Output parameters:
1435 *   info->data_addr is set according to arguments of the PORT command.
1436 *   info->use_default is set to 0 on success, 1 on failure.
1437 */
1438static void
1439command_port(FTPD_SessionInfo_t *info, char const *args)
1440{
1441  enum { NUM_FIELDS = 6 };
1442  unsigned int a[NUM_FIELDS];
1443  int n;
1444
1445  close_data_socket(info);
1446
1447  n = sscanf(args, "%u,%u,%u,%u,%u,%u", a+0, a+1, a+2, a+3, a+4, a+5);
1448  if(NUM_FIELDS == n)
1449  {
1450    int i;
1451    union {
1452      uint8_t b[NUM_FIELDS];
1453      struct {
1454        uint32_t ip;
1455        uint16_t port;
1456      } u ;
1457    } ip_info;
1458
1459    for(i = 0; i < NUM_FIELDS; ++i)
1460    {
1461      if(a[i] > 255)
1462        break;
1463      ip_info.b[i] = (uint8_t)a[i];
1464    }
1465
1466    if(i == NUM_FIELDS)
1467    {
1468      /* Note: while it contradicts with RFC959, we don't allow PORT command
1469       * to specify IP address different than those of the originating client
1470       * for the sake of safety. */
1471      if (ip_info.u.ip == info->def_addr.sin_addr.s_addr)
1472      {
1473        info->data_addr.sin_addr.s_addr = ip_info.u.ip;
1474        info->data_addr.sin_port        = ip_info.u.port;
1475        info->data_addr.sin_family      = AF_INET;
1476        memset(info->data_addr.sin_zero, 0, sizeof(info->data_addr.sin_zero));
1477
1478        info->use_default = 0;
1479        send_reply(info, 200, "PORT command successful.");
1480        return; /* success */
1481      }
1482      else
1483      {
1484        send_reply(info, 425, "Address doesn't match peer's IP.");
1485        return;
1486      }
1487    }
1488  }
1489  send_reply(info, 501, "Syntax error.");
1490}
1491
1492
1493/*
1494 * command_pasv
1495 *
1496 * Handle FTP PASV command.
1497 * Open socket, listen for and accept connection on it.
1498 *
1499 * Input parameters:
1500 *   info - corresponding SessionInfo structure
1501 *
1502 * Output parameters:
1503 *   info->pasv_socket is set to the descriptor of the data socket
1504 */
1505static void
1506command_pasv(FTPD_SessionInfo_t *info)
1507{
1508  int s = -1;
1509  int err = 1;
1510
1511  close_data_socket(info);
1512
1513  s = socket(PF_INET, SOCK_STREAM, 0);
1514  if (s < 0)
1515    syslog(LOG_ERR, "ftpd: Error creating PASV socket: %s", serr());
1516  else
1517  {
1518    struct sockaddr_in addr;
1519    socklen_t addrLen = sizeof(addr);
1520
1521    addr = info->ctrl_addr;
1522    addr.sin_port = htons(0);
1523
1524    if (0 > bind(s, (struct sockaddr *)&addr, addrLen))
1525      syslog(LOG_ERR, "ftpd: Error binding PASV socket: %s", serr());
1526    else if (0 > listen(s, 1))
1527      syslog(LOG_ERR, "ftpd: Error listening on PASV socket: %s", serr());
1528    else if(set_socket_timeout(s, info->idle))
1529    {
1530      char buf[FTPD_BUFSIZE];
1531      unsigned char const *ip, *p;
1532
1533      getsockname(s, (struct sockaddr *)&addr, &addrLen);
1534      ip = (unsigned char const*)&(addr.sin_addr);
1535      p  = (unsigned char const*)&(addr.sin_port);
1536      snprintf(buf, FTPD_BUFSIZE, "Entering passive mode (%u,%u,%u,%u,%u,%u).",
1537        ip[0], ip[1], ip[2], ip[3], p[0], p[1]);
1538      send_reply(info, 227, buf);
1539
1540      info->pasv_socket = accept(s, (struct sockaddr *)&addr, &addrLen);
1541      if (0 > info->pasv_socket)
1542        syslog(LOG_ERR, "ftpd: Error accepting PASV connection: %s", serr());
1543      else
1544      {
1545        close_socket(s);
1546        s = -1;
1547        err = 0;
1548      }
1549    }
1550  }
1551  if(err)
1552  {
1553    /* (OSV) The note is from FreeBSD FTPD.
1554     * Note: a response of 425 is not mentioned as a possible response to
1555     * the PASV command in RFC959.  However, it has been blessed as a
1556     * legitimate response by Jon Postel in a telephone conversation
1557     * with Rick Adams on 25 Jan 89. */
1558    send_reply(info, 425, "Can't open passive connection.");
1559    close_socket(s);
1560  }
1561}
1562
1563
1564/*
1565 * skip_options
1566 *
1567 * Utility routine to skip options (if any) from input command.
1568 *
1569 * Input parameters:
1570 *   p  - pointer to pointer to command
1571 *
1572 * Output parameters:
1573 *   p  - is changed to point to first non-option argument
1574 */
1575static void
1576skip_options(char **p)
1577{
1578  char* buf = *p;
1579  char* last = NULL;
1580  while(1) {
1581    while(isspace((unsigned char)*buf))
1582      ++buf;
1583    if(*buf == '-') {
1584      if(*++buf == '-') { /* `--' should terminate options */
1585        if(isspace((unsigned char)*++buf)) {
1586          last = buf;
1587          do ++buf;
1588          while(isspace((unsigned char)*buf));
1589          break;
1590        }
1591      }
1592      while(*buf && !isspace((unsigned char)*buf))
1593        ++buf;
1594      last = buf;
1595    }
1596    else
1597      break;
1598  }
1599  if(last)
1600    *last = '\0';
1601  *p = buf;
1602}
1603
1604/*
1605 * split_command
1606 *
1607 * Split command into command itself, options, and arguments. Command itself
1608 * is converted to upper case.
1609 *
1610 * Input parameters:
1611 *   buf - initial command string
1612 *
1613 * Output parameter:
1614 *   buf  - is modified by inserting '\0' at ends of split entities
1615 *   cmd  - upper-cased command code
1616 *   opts - string containing all the options
1617 *   args - string containing all the arguments
1618 */
1619void
1620split_command(char *buf, char **cmd, char **opts, char **args)
1621{
1622  char* eoc;
1623  char* p = buf;
1624  while(isspace((unsigned char)*p))
1625    ++p;
1626  *cmd = p;
1627  while(*p && !isspace((unsigned char)*p))
1628  {
1629    *p = toupper((unsigned char)*p);
1630    ++p;
1631  }
1632  eoc = p;
1633  if(*p)
1634    *p++ = '\0';
1635  while(isspace((unsigned char)*p))
1636    ++p;
1637  *opts = p;
1638  skip_options(&p);
1639  *args = p;
1640  if(*opts == p)
1641    *opts = eoc;
1642  while(*p && *p != '\r' && *p != '\n')
1643    ++p;
1644  if(*p)
1645    *p++ = '\0';
1646}
1647
1648/*
1649 * exec_command
1650 *
1651 * Parse and execute FTP command.
1652 *
1653 * FIXME: This section is somewhat of a hack.  We should have a better
1654 *        way to parse commands.
1655 *
1656 * Input parameters:
1657 *   info - corresponding SessionInfo structure
1658 *   cmd  - command to be executed (upper-case)
1659 *   args - arguments of the command
1660 *
1661 * Output parameters:
1662 *    NONE
1663 */
1664static void
1665exec_command(FTPD_SessionInfo_t *info, char* cmd, char* args)
1666{
1667  char fname[FTPD_BUFSIZE];
1668  int wrong_command = 0;
1669
1670  fname[0] = '\0';
1671
1672  if (!strcmp("PORT", cmd))
1673  {
1674    command_port(info, args);
1675  }
1676  else if (!strcmp("PASV", cmd))
1677  {
1678    command_pasv(info);
1679  }
1680  else if (!strcmp("RETR", cmd))
1681  {
1682    strncpy(fname, args, 254);
1683    command_retrieve(info, fname);
1684  }
1685  else if (!strcmp("STOR", cmd))
1686  {
1687    strncpy(fname, args, 254);
1688    command_store(info, fname);
1689  }
1690  else if (!strcmp("LIST", cmd))
1691  {
1692    strncpy(fname, args, 254);
1693    command_list(info, fname, 1);
1694  }
1695  else if (!strcmp("NLST", cmd))
1696  {
1697    strncpy(fname, args, 254);
1698    command_list(info, fname, 0);
1699  }
1700  else if (!strcmp("MDTM", cmd))
1701  {
1702    strncpy(fname, args, 254);
1703    command_mdtm(info, fname);
1704  }
1705  else if (!strcmp("SYST", cmd))
1706  {
1707    send_reply(info, 215, FTPD_SYSTYPE);
1708  }
1709  else if (!strcmp("TYPE", cmd))
1710  {
1711    if (args[0] == 'I')
1712    {
1713      info->xfer_mode = TYPE_I;
1714      send_reply(info, 200, "Type set to I.");
1715    }
1716    else if (args[0] == 'A')
1717    {
1718      info->xfer_mode = TYPE_A;
1719      send_reply(info, 200, "Type set to A.");
1720    }
1721    else
1722    {
1723      info->xfer_mode = TYPE_I;
1724      send_reply(info, 504, "Type not implemented.  Set to I.");
1725    }
1726  }
1727  else if (!strcmp("USER", cmd))
1728  {
1729    sscanf(args, "%254s", fname);
1730    if (info->user)
1731      free(info->user);
1732    if (info->pass)
1733      free(info->pass);
1734    info->pass = NULL;
1735    info->user = strdup(fname);
1736    if (rtems_ftpd_configuration.login &&
1737      !rtems_ftpd_configuration.login(info->user, NULL)) {
1738      info->auth = false;
1739      send_reply(info, 331, "User name okay, need password.");
1740    } else {
1741      info->auth = true;
1742      send_reply(info, 230, "User logged in.");
1743    }
1744  }
1745  else if (!strcmp("PASS", cmd))
1746  {
1747    sscanf(args, "%254s", fname);
1748    if (info->pass)
1749      free(info->pass);
1750    info->pass = strdup(fname);
1751    if (!info->user) {
1752      send_reply(info, 332, "Need account to log in");
1753    } else {
1754      if (rtems_ftpd_configuration.login &&
1755        !rtems_ftpd_configuration.login(info->user, info->pass)) {
1756        info->auth = false;
1757        send_reply(info, 530, "Not logged in.");
1758      } else {
1759        info->auth = true;
1760        send_reply(info, 230, "User logged in.");
1761      }
1762    }
1763  }
1764  else if (!strcmp("DELE", cmd))
1765  {
1766    if(!can_write() || !info->auth)
1767    {
1768      send_reply(info, 550, "Access denied.");
1769    }
1770    else if (
1771      strncpy(fname, args, 254) &&
1772      unlink(fname) == 0)
1773    {
1774      send_reply(info, 257, "DELE successful.");
1775    }
1776    else
1777    {
1778      send_reply(info, 550, "DELE failed.");
1779    }
1780  }
1781  else if (!strcmp("SITE", cmd))
1782  {
1783    char* opts;
1784    split_command(args, &cmd, &opts, &args);
1785    if(!strcmp("CHMOD", cmd))
1786    {
1787      int mask;
1788
1789      if(!can_write() || !info->auth)
1790      {
1791        send_reply(info, 550, "Access denied.");
1792      }
1793      else {
1794        char *c;
1795        c = strchr(args, ' ');
1796        if((c != NULL) && (sscanf(args, "%o", &mask) == 1) && strncpy(fname, c+1, 254) 
1797          && (chmod(fname, (mode_t)mask) == 0))
1798          send_reply(info, 257, "CHMOD successful.");
1799        else
1800          send_reply(info, 550, "CHMOD failed.");
1801      }
1802    }
1803    else
1804      wrong_command = 1;
1805  }
1806  else if (!strcmp("RMD", cmd))
1807  {
1808    if(!can_write() || !info->auth)
1809    {
1810      send_reply(info, 550, "Access denied.");
1811    }
1812    else if (
1813      strncpy(fname, args, 254) &&
1814      rmdir(fname) == 0)
1815    {
1816      send_reply(info, 257, "RMD successful.");
1817    }
1818    else
1819    {
1820      send_reply(info, 550, "RMD failed.");
1821    }
1822  }
1823  else if (!strcmp("MKD", cmd))
1824  {
1825    if(!can_write() || !info->auth)
1826    {
1827      send_reply(info, 550, "Access denied.");
1828    }
1829    else if (
1830      strncpy(fname, args, 254) &&
1831      mkdir(fname, S_IRWXU | S_IRWXG | S_IRWXO) == 0)
1832    {
1833      send_reply(info, 257, "MKD successful.");
1834    }
1835    else
1836    {
1837      send_reply(info, 550, "MKD failed.");
1838    }
1839  }
1840  else if (!strcmp("CWD", cmd))
1841  {
1842    strncpy(fname, args, 254);
1843    command_cwd(info, fname);
1844  }
1845  else if (!strcmp("CDUP", cmd))
1846  {
1847    command_cwd(info, "..");
1848  }
1849  else if (!strcmp("PWD", cmd))
1850  {
1851    command_pwd(info);
1852  }
1853  else
1854    wrong_command = 1;
1855
1856  if(wrong_command)
1857    send_reply(info, 500, "Command not understood.");
1858}
1859
1860
1861/*
1862 * session
1863 *
1864 * This task handles single session.  It is waked up when the FTP daemon gets a
1865 * service request from a remote machine.  Here, we watch for commands that
1866 * will come through the control connection.  These commands are then parsed
1867 * and executed until the connection is closed, either unintentionally or
1868 * intentionally with the "QUIT" command.
1869 *
1870 * Input parameters:
1871 *   arg - pointer to corresponding SessionInfo.
1872 *
1873 * Output parameters:
1874 *   NONE
1875 */
1876static void
1877session(rtems_task_argument arg)
1878{
1879  FTPD_SessionInfo_t  *const info = (FTPD_SessionInfo_t  *)arg;
1880  int chroot_made = 0;
1881
1882  rtems_libio_set_private_env();
1883
1884  /* chroot() can fail here because the directory may not exist yet. */
1885  chroot_made = chroot(ftpd_root) == 0;
1886
1887  while(1)
1888  {
1889    rtems_event_set set;
1890
1891    rtems_event_receive(FTPD_RTEMS_EVENT, RTEMS_EVENT_ANY, RTEMS_NO_TIMEOUT,
1892      &set);
1893
1894    chroot_made = chroot_made || chroot(ftpd_root) == 0;
1895    chdir("/");
1896
1897    errno = 0;
1898
1899    send_reply(info, 220, FTPD_SERVER_MESSAGE);
1900
1901    while (1)
1902    {
1903      char buf[FTPD_BUFSIZE];
1904      char *cmd, *opts, *args;
1905
1906      if (fgets(buf, FTPD_BUFSIZE, info->ctrl_fp) == NULL)
1907      {
1908        syslog(LOG_INFO, "ftpd: Connection aborted.");
1909        break;
1910      }
1911
1912      split_command(buf, &cmd, &opts, &args);
1913
1914      if (!strcmp("QUIT", cmd))
1915      {
1916        send_reply(info, 221, "Goodbye.");
1917        break;
1918      }
1919      else
1920      {
1921        exec_command(info, cmd, args);
1922      }
1923    }
1924
1925    /* Close connection and put ourselves back into the task pool. */
1926    close_data_socket(info);
1927    close_stream(info);
1928    free(info->user);
1929    free(info->pass);
1930    task_pool_release(info);
1931  }
1932}
1933
1934
1935/*
1936 * daemon
1937 *
1938 * This task runs forever.  It waits for service requests on the FTP port
1939 * (port 21 by default).  When a request is received, it opens a new session
1940 * to handle those requests until the connection is closed.
1941 *
1942 * Input parameters:
1943 *   NONE
1944 *
1945 * Output parameters:
1946 *   NONE
1947 */
1948static void
1949daemon(rtems_task_argument args __attribute__((unused)))
1950{
1951  int                 s;
1952  socklen_t           addrLen;
1953  struct sockaddr_in  addr;
1954  FTPD_SessionInfo_t  *info = NULL;
1955
1956
1957  s = socket(PF_INET, SOCK_STREAM, 0);
1958  if (s < 0)
1959    syslog(LOG_ERR, "ftpd: Error creating socket: %s", serr());
1960
1961  addr.sin_family      = AF_INET;
1962  addr.sin_port        = htons(rtems_ftpd_configuration.port);
1963  addr.sin_addr.s_addr = htonl(INADDR_ANY);
1964  memset(addr.sin_zero, 0, sizeof(addr.sin_zero));
1965
1966  if (0 > bind(s, (struct sockaddr *)&addr, sizeof(addr)))
1967    syslog(LOG_ERR, "ftpd: Error binding control socket: %s", serr());
1968  else if (0 > listen(s, 1))
1969    syslog(LOG_ERR, "ftpd: Error listening on control socket: %s", serr());
1970  else while (1)
1971  {
1972    int ss;
1973    addrLen = sizeof(addr);
1974    ss = accept(s, (struct sockaddr *)&addr, &addrLen);
1975    if (0 > ss)
1976      syslog(LOG_ERR, "ftpd: Error accepting control connection: %s", serr());
1977    else if(!set_socket_timeout(ss, ftpd_timeout))
1978      close_socket(ss);
1979    else
1980    {
1981      info = task_pool_obtain();
1982      if (NULL == info)
1983      {
1984        close_socket(ss);
1985      }
1986      else
1987      {
1988        info->ctrl_socket = ss;
1989        if ((info->ctrl_fp = fdopen(info->ctrl_socket, "r+")) == NULL)
1990        {
1991          syslog(LOG_ERR, "ftpd: fdopen() on socket failed: %s", serr());
1992          close_stream(info);
1993          task_pool_release(info);
1994        }
1995        else
1996        {
1997          /* Initialize corresponding SessionInfo structure */
1998          info->def_addr = addr;
1999          if(0 > getsockname(ss, (struct sockaddr *)&addr, &addrLen))
2000          {
2001            syslog(LOG_ERR, "ftpd: getsockname(): %s", serr());
2002            close_stream(info);
2003            task_pool_release(info);
2004          }
2005          else
2006          {
2007            info->use_default = 1;
2008            info->ctrl_addr  = addr;
2009            info->pasv_socket = -1;
2010            info->data_socket = -1;
2011            info->xfer_mode   = TYPE_A;
2012            info->data_addr.sin_port =
2013              htons(ntohs(info->ctrl_addr.sin_port) - 1);
2014            info->idle = ftpd_timeout;
2015            info->user = NULL;
2016            info->pass = NULL;
2017            if (rtems_ftpd_configuration.login)
2018              info->auth = false;
2019            else
2020              info->auth = true;
2021            /* Wakeup the session task.  The task will call task_pool_release
2022               after it closes connection. */
2023            rtems_event_send(info->tid, FTPD_RTEMS_EVENT);
2024          }
2025        }
2026      }
2027    }
2028  }
2029  rtems_task_delete(RTEMS_SELF);
2030}
2031
2032
2033/*
2034 * rtems_ftpd_start
2035 *
2036 * Here, we start the FTPD task which waits for FTP requests and services
2037 * them.  This procedure returns to its caller once the task is started.
2038 *
2039 *
2040 * Input parameters:
2041 *
2042 * Output parameters:
2043 *    returns RTEMS_SUCCESSFUL on successful start of the daemon.
2044 */
2045int
2046rtems_initialize_ftpd(void)
2047{
2048  rtems_status_code   sc;
2049  rtems_id            tid;
2050  rtems_task_priority priority;
2051  int count;
2052
2053  if (rtems_ftpd_configuration.port == 0)
2054  {
2055    rtems_ftpd_configuration.port = FTPD_CONTROL_PORT;
2056  }
2057
2058  if (rtems_ftpd_configuration.priority == 0)
2059  {
2060    rtems_ftpd_configuration.priority = 40;
2061  }
2062  priority = rtems_ftpd_configuration.priority;
2063
2064  ftpd_timeout = rtems_ftpd_configuration.idle;
2065  if (ftpd_timeout < 0)
2066    ftpd_timeout = 0;
2067  rtems_ftpd_configuration.idle = ftpd_timeout;
2068
2069  ftpd_access = rtems_ftpd_configuration.access;
2070
2071  if (rtems_ftpd_configuration.tasks_count <= 0)
2072    rtems_ftpd_configuration.tasks_count = 1;
2073  count = rtems_ftpd_configuration.tasks_count;
2074
2075  if (!task_pool_init(count, priority))
2076  {
2077    syslog(LOG_ERR, "ftpd: Could not initialize task pool.");
2078    return RTEMS_UNSATISFIED;
2079  }
2080
2081  sc = rtems_task_create(rtems_build_name('F', 'T', 'P', 'D'),
2082    priority, RTEMS_MINIMUM_STACK_SIZE,
2083    RTEMS_PREEMPT | RTEMS_NO_TIMESLICE | RTEMS_NO_ASR |
2084    RTEMS_INTERRUPT_LEVEL(0),
2085    RTEMS_NO_FLOATING_POINT | RTEMS_LOCAL,
2086    &tid);
2087
2088  if (sc == RTEMS_SUCCESSFUL)
2089  {
2090    sc = rtems_task_start(tid, daemon, 0);
2091    if (sc != RTEMS_SUCCESSFUL)
2092      rtems_task_delete(tid);
2093  }
2094
2095  if (sc != RTEMS_SUCCESSFUL)
2096  {
2097    task_pool_done(count);
2098    syslog(LOG_ERR, "ftpd: Could not create/start FTP daemon: %s",
2099      rtems_status_text(sc));
2100    return RTEMS_UNSATISFIED;
2101  }
2102
2103  ftpd_root = "/";
2104  if (
2105    rtems_ftpd_configuration.root &&
2106    rtems_ftpd_configuration.root[0] == '/'
2107  )
2108    ftpd_root = rtems_ftpd_configuration.root;
2109
2110  rtems_ftpd_configuration.root = ftpd_root;
2111
2112  syslog(LOG_INFO, "ftpd: FTP daemon started (%d session%s max)",
2113    count, ((count > 1) ? "s" : ""));
2114
2115  return RTEMS_SUCCESSFUL;
2116}
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