source: rtems/cpukit/ftpd/ftpd.c @ bde6ac20

Last change on this file since bde6ac20 was bde6ac20, checked in by kuaLeYi <kualeyidxa@…>, on Nov 20, 2018 at 3:45:51 PM

Misc: Minor English fixes (GCI 2018)

  • Property mode set to 100644
File size: 51.3 KB
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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.  Seems 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 not 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
100/*************************************************************************
101 *                                 ftpd.c
102 *************************************************************************
103 * Description:
104 *
105 *    This file contains the daemon which services requests that appear
106 *    on the FTP port.  This server is compatible with FTP, but it
107 *    also provides 'hooks' to make it usable in situations where files
108 *    are not used/necessary.  Once the server is started, it runs
109 *    forever.
110 *
111 *
112 *    Organization:
113 *
114 *       The FTP daemon is started upon boot along with a (configurable)
115 *       number of tasks to handle sessions.  It runs all the time and
116 *       waits for connections on the known FTP port (21).  When
117 *       a connection is made, it wakes-up a 'session' task.  That
118 *       session then interacts with the remote host.  When the session
119 *       is complete, the session task goes to sleep.  The daemon still
120 *       runs, however.
121 *
122 *
123 * Supported commands are:
124 *
125 * RETR xxx     - Sends a file from the client.
126 * STOR xxx     - Receives a file from the client.  xxx = filename.
127 * LIST xxx     - Sends a file list to the client.
128 * NLST xxx     - Sends a file list to the client.
129 * USER         - Does nothing.
130 * PASS         - Does nothing.
131 * SYST         - Replies with the system type (`RTEMS').
132 * DELE xxx     - Delete file xxx.
133 * MKD xxx      - Create directory xxx.
134 * RMD xxx      - Remove directory xxx.
135 * PWD          - Print working directory.
136 * CWD xxx      - Change working directory.
137 * CDUP         - Change to upper directory.
138 * SITE CHMOD xxx yyy - Change permissions on file yyy to xxx.
139 * PORT a,b,c,d,x,y   - Setup for a data port to IP address a.b.c.d
140 *                      and port (x*256 + y).
141 * MDTM xxx     - Send file modification date/time to the client.
142 *                xxx = filename.
143 * PASV         - Use passive mode data connection.
144 *
145 *
146 * The public routines contained in this file are:
147 *
148 *    rtems_initialize_ftpd - Initializes and starts the server daemon,
149 *                            then returns to its caller.
150 *
151 *------------------------------------------------------------------------
152 * Jake Janovetz
153 * University of Illinois
154 * 1406 West Green Street
155 * Urbana IL  61801
156 *************************************************************************
157 * Change History:
158 *  12/01/97   - Creation (JWJ)
159 *  2001-01-08 - Changes by OSV
160 *  2010-04-29 - Authentication added by AV
161 *************************************************************************/
162
163/*************************************************************************
164 * Meanings of first and second digits of reply codes:
165 *
166 * Reply:  Description:
167 *-------- --------------
168 *  1yz    Positive preliminary reply.  The action is being started but
169 *         expect another reply before sending another command.
170 *  2yz    Positive completion reply.  A new command can be sent.
171 *  3yz    Positive intermediate reply.  The command has been accepted
172 *         but another command must be sent.
173 *  4yz    Transient negative completion reply.  The requested action did
174 *         not take place, but the error condition is temporary so the
175 *         command can be reissued later.
176 *  5yz    Permanent negative completion reply.  The command was not
177 *         accepted and should not be retried.
178 *-------------------------------------------------------------------------
179 *  x0z    Syntax errors.
180 *  x1z    Information.
181 *  x2z    Connections.  Replies referring to the control or data
182 *         connections.
183 *  x3z    Authentication and accounting.  Replies for the login or
184 *         accounting commands.
185 *  x4z    Unspecified.
186 *  x5z    Filesystem status.
187 *************************************************************************/
188
189#if HAVE_CONFIG_H
190#include "config.h"
191#endif
192
193#include <stdio.h>
194#include <stdlib.h>
195#include <string.h>
196#include <unistd.h>
197#include <fcntl.h>
198#include <dirent.h>
199#include <errno.h>
200#include <ctype.h>
201#include <inttypes.h>
202#include <sched.h>
203
204#include <rtems.h>
205#include <rtems/error.h>
206#include <rtems/ftpd.h>
207#include <rtems/libio.h>
208#include <rtems/thread.h>
209#include <rtems/userenv.h>
210#include <syslog.h>
211
212#include <sys/types.h>
213#include <sys/socket.h>
214#include <arpa/ftp.h>
215#include <netinet/in.h>
216
217
218#ifdef __GNUC__
219/* change to #if 1 to disable syslog entirely */
220#if 0
221#undef  syslog
222#define syslog(a, b, ...) while(0){}
223#endif
224#endif
225
226#define FTPD_SERVER_MESSAGE  "RTEMS FTP server (Version 1.1-JWJ) ready."
227
228#define FTPD_SYSTYPE "UNIX Type: L8"
229
230/* Seems to be unused */
231#if 0
232#define FTPD_WELCOME_MESSAGE \
233   "Welcome to the RTEMS FTP server.\n" \
234   "\n" \
235   "Login accepted.\n"
236#endif
237
238/* Event to be used by session tasks for waiting */
239enum
240{
241  FTPD_RTEMS_EVENT = RTEMS_EVENT_1
242};
243
244/* Configuration table */
245static struct rtems_ftpd_configuration *ftpd_config;
246
247/* this is not prototyped in strict ansi mode */
248FILE *fdopen (int fildes, const char *mode);
249
250/*SessionInfo structure.
251 *
252 * The following structure is allocated for each session.
253 */
254typedef struct
255{
256  struct sockaddr_in  ctrl_addr;   /* Control connection self address */
257  struct sockaddr_in  data_addr;   /* Data address set by PORT command */
258  struct sockaddr_in  def_addr;    /* Default address for data */
259  int                 use_default; /* 1 - use default address for data */
260  FILE                *ctrl_fp;    /* File pointer for control connection */
261  int                 ctrl_socket; /* Socket for ctrl connection */
262  int                 pasv_socket; /* Socket for PASV connection */
263  int                 data_socket; /* Socket for data connection */
264  int                 idle;        /* Timeout in seconds */
265  int                 xfer_mode;   /* Transfer mode (ASCII/binary) */
266  rtems_id            tid;         /* Task id */
267  char                *user;       /* user name (0 if not supplied) */
268  char                user_buf[256]; /* user name buffer */
269  bool                auth;        /* true if user/pass was valid, false if not or not supplied */
270} FTPD_SessionInfo_t;
271
272
273/*
274 * TaskPool structure.
275 */
276typedef struct
277{
278  FTPD_SessionInfo_t       *info;
279  FTPD_SessionInfo_t       **queue;
280  int                      count;
281  int                      head;
282  int                      tail;
283  rtems_mutex              mutex;
284  rtems_counting_semaphore sem;
285} FTPD_TaskPool_t;
286
287/*
288 * Task pool instance.
289 */
290static FTPD_TaskPool_t task_pool;
291
292/*
293 * Root directory
294 */
295
296static char const* ftpd_root = "/";
297
298/*
299 * Default idle timeout for sockets in seconds.
300 */
301static int ftpd_timeout = 0;
302
303/*
304 * Global access flags.
305 */
306static int ftpd_access = 0;
307
308static void
309yield(void)
310{
311/*
312 * If we do not build for the legacy network stack, then we use the libbsd.  In
313 * the libbsd there is no global network stack semaphore which provides round
314 * robin fairness for threads of equal priority.
315 */
316#ifndef RTEMS_NETWORKING
317  sched_yield();
318#endif
319}
320
321/*
322 * serr
323 *
324 * Return error string corresponding to current 'errno'.
325 *
326 */
327static char const*
328serr(void)
329{
330  int err = errno;
331  errno = 0;
332  return strerror(err);
333}
334
335/*
336 * Utility routines for access control.
337 *
338 */
339
340static int
341can_read(void)
342{
343  return (ftpd_access & FTPD_NO_READ) == 0;
344}
345
346static int
347can_write(void)
348{
349  return (ftpd_access & FTPD_NO_WRITE) == 0;
350}
351
352/*
353 * Task pool management routines
354 *
355 */
356
357
358/*
359 * task_pool_done
360 *
361 * Cleanup task pool.
362 *
363 * Input parameters:
364 *   count - number of entries in task pool to cleanup
365 *
366 * Output parameters:
367 *   NONE
368 *
369 */
370static void
371task_pool_done(int count)
372{
373  int i;
374  for(i = 0; i < count; ++i)
375    rtems_task_delete(task_pool.info[i].tid);
376  free(task_pool.info);
377  free(task_pool.queue);
378  rtems_mutex_destroy(&task_pool.mutex);
379  rtems_counting_semaphore_destroy(&task_pool.sem);
380  task_pool.info = 0;
381  task_pool.queue = 0;
382  task_pool.count = 0;
383}
384
385/*
386 * task_pool_init
387 *
388 * Initialize task pool.
389 *
390 * Input parameters:
391 *   count    - number of entries in task pool to create
392 *   priority - priority tasks are started with
393 *
394 * Output parameters:
395 *   returns 1 on success, 0 on failure.
396 *
397 */
398static void session(rtems_task_argument arg); /* Forward declare */
399
400static int
401task_pool_init(int count, rtems_task_priority priority)
402{
403  int i;
404  rtems_status_code sc;
405  char id = 'a';
406
407  task_pool.count = 0;
408  task_pool.head = task_pool.tail = 0;
409
410  rtems_mutex_init(&task_pool.mutex, "FTPD");
411  rtems_counting_semaphore_init(&task_pool.sem, "FTPD", (unsigned int) count);
412
413  task_pool.info = (FTPD_SessionInfo_t*)
414    malloc(sizeof(FTPD_SessionInfo_t) * count);
415  task_pool.queue = (FTPD_SessionInfo_t**)
416    malloc(sizeof(FTPD_SessionInfo_t*) * count);
417  if (NULL == task_pool.info || NULL == task_pool.queue)
418  {
419    task_pool_done(0);
420    syslog(LOG_ERR, "ftpd: Not enough memory");
421    return 0;
422  }
423
424  for(i = 0; i < count; ++i)
425  {
426    FTPD_SessionInfo_t *info = &task_pool.info[i];
427    sc = rtems_task_create(rtems_build_name('F', 'T', 'P', id),
428      priority, FTPD_STACKSIZE,
429      RTEMS_PREEMPT | RTEMS_NO_TIMESLICE |
430      RTEMS_NO_ASR | RTEMS_INTERRUPT_LEVEL(0),
431      RTEMS_FLOATING_POINT | RTEMS_LOCAL,
432      &info->tid);
433    if (sc == RTEMS_SUCCESSFUL)
434    {
435      sc = rtems_task_start(
436        info->tid, session, (rtems_task_argument)info);
437      if (sc != RTEMS_SUCCESSFUL)
438        task_pool_done(i);
439    }
440    else
441      task_pool_done(i + 1);
442    if (sc != RTEMS_SUCCESSFUL)
443    {
444      syslog(LOG_ERR, "ftpd: Could not create/start FTPD session: %s",
445        rtems_status_text(sc));
446      return 0;
447    }
448    task_pool.queue[i] = task_pool.info + i;
449    if (++id > 'z')
450      id = 'a';
451  }
452  task_pool.count = count;
453  return 1;
454}
455
456/*
457 * task_pool_obtain
458 *
459 * Obtain free task from task pool.
460 *
461 * Input parameters:
462 *   NONE
463 *
464 * Output parameters:
465 *   returns pointer to the corresponding SessionInfo structure on success,
466 *           NULL if there are no free tasks in the pool.
467 *
468 */
469static FTPD_SessionInfo_t*
470task_pool_obtain(void)
471{
472  FTPD_SessionInfo_t* info = 0;
473  rtems_counting_semaphore_wait(&task_pool.sem);
474  rtems_mutex_lock(&task_pool.mutex);
475  info = task_pool.queue[task_pool.head];
476  if(++task_pool.head >= task_pool.count)
477    task_pool.head = 0;
478  rtems_mutex_unlock(&task_pool.mutex);
479  return info;
480}
481
482/*
483 * task_pool_release
484 *
485 * Return task obtained by 'obtain()' back to the task pool.
486 *
487 * Input parameters:
488 *   info  - pointer to corresponding SessionInfo structure.
489 *
490 * Output parameters:
491 *   NONE
492 *
493 */
494static void
495task_pool_release(FTPD_SessionInfo_t* info)
496{
497  rtems_mutex_lock(&task_pool.mutex);
498  task_pool.queue[task_pool.tail] = info;
499  if(++task_pool.tail >= task_pool.count)
500    task_pool.tail = 0;
501  rtems_mutex_unlock(&task_pool.mutex);
502  rtems_counting_semaphore_post(&task_pool.sem);
503}
504
505/*
506 * End of task pool routines
507 */
508
509/*
510 * Function: send_reply
511 *
512 *
513 *    This procedure sends a reply to the client via the control
514 *    connection.
515 *
516 *
517 * Input parameters:
518 *   code  - 3-digit reply code.
519 *   text  - Reply text.
520 *
521 * Output parameters:
522 *   NONE
523 */
524static void
525send_reply(FTPD_SessionInfo_t  *info, int code, const char *text)
526{
527  text = text != NULL ? text : "";
528  fprintf(info->ctrl_fp, "%d %.70s\r\n", code, text);
529  fflush(info->ctrl_fp);
530}
531
532
533/*
534 * close_socket
535 *
536 * Close socket.
537 *
538 * Input parameters:
539 *   s - socket descriptor.
540 *   seconds - number of seconds the timeout should be,
541 *             if >= 0 - infinite timeout (no timeout).
542 *
543 * Output parameters:
544 *   returns 1 on success, 0 on failure.
545 */
546static int
547set_socket_timeout(int s, int seconds)
548{
549  int res = 0;
550  struct timeval tv;
551  int len = sizeof(tv);
552
553  if(seconds < 0)
554    seconds = 0;
555  tv.tv_usec = 0;
556  tv.tv_sec  = seconds;
557  if(0 != setsockopt(s, SOL_SOCKET, SO_SNDTIMEO, &tv, len))
558    syslog(LOG_ERR, "ftpd: Can't set send timeout on socket: %s.", serr());
559  else if(0 != setsockopt(s, SOL_SOCKET, SO_RCVTIMEO, &tv, len))
560    syslog(LOG_ERR, "ftpd: Can't set receive timeout on socket: %s.", serr());
561  else
562    res = 1;
563  return res;
564}
565
566/*
567 * close_socket
568 *
569 * Close socket.
570 *
571 * Input parameters:
572 *   s - socket descriptor to be closed.
573 *
574 * Output parameters:
575 *   returns 1 on success, 0 on failure
576 */
577static int
578close_socket(int s)
579{
580  if (0 <= s)
581  {
582    if (0 != close(s))
583    {
584      shutdown(s, 2);
585      if (0 != close(s))
586        return 0;
587    }
588  }
589  return 1;
590}
591
592/*
593 * data_socket
594 *
595 * Create data socket for session.
596 *
597 * Input parameters:
598 *   info - corresponding SessionInfo structure
599 *
600 * Output parameters:
601 *   returns socket descriptor, or -1 if failure
602 *
603 */
604static int
605data_socket(FTPD_SessionInfo_t *info)
606{
607  int s = info->pasv_socket;
608  if(0 > s)
609  {
610    int on = 1;
611    s = socket(PF_INET, SOCK_STREAM, 0);
612    if(0 > s)
613      send_reply(info, 425, "Can't create data socket.");
614    else if(0 > setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)))
615    {
616      close_socket(s);
617      s = -1;
618    }
619    else
620    {
621      struct sockaddr_in data_source;
622      int tries;
623
624      /* anchor socket to avoid multi-homing problems */
625      data_source = info->ctrl_addr;
626      data_source.sin_port = htons(20); /* ftp-data port */
627      for(tries = 1; tries < 10; ++tries)
628      {
629        errno = 0;
630        if(bind(s, (struct sockaddr *)&data_source, sizeof(data_source)) >= 0)
631          break;
632        if (errno != EADDRINUSE)
633          tries = 10;
634        else
635          rtems_task_wake_after(tries * 10);
636      }
637      if(tries >= 10)
638      {
639        send_reply(info, 425, "Can't bind data socket.");
640        close_socket(s);
641        s = -1;
642      }
643      else
644      {
645        struct sockaddr_in *data_dest =
646          (info->use_default) ? &info->def_addr : &info->data_addr;
647        if(0 > connect(s, (struct sockaddr *)data_dest, sizeof(*data_dest)))
648        {
649          send_reply(info, 425, "Can't connect data socket.");
650          close_socket(s);
651          s = -1;
652        }
653      }
654    }
655  }
656  info->data_socket = s;
657  info->use_default = 1;
658  if(s >= 0)
659    set_socket_timeout(s, info->idle);
660  return s;
661}
662
663/*
664 * close_data_socket
665 *
666 * Close data socket for session.
667 *
668 * Input parameters:
669 *   info - corresponding SessionInfo structure
670 *
671 * Output parameters:
672 *   NONE
673 *
674 */
675static void
676close_data_socket(FTPD_SessionInfo_t *info)
677{
678  /* As at most one data socket could be open simultaneously and in some cases
679     data_socket == pasv_socket, we select socket to close, then close it. */
680  int s = info->data_socket;
681  if(0 > s)
682    s = info->pasv_socket;
683  if(!close_socket(s))
684    syslog(LOG_ERR, "ftpd: Error closing data socket.");
685  info->data_socket = -1;
686  info->pasv_socket = -1;
687  info->use_default = 1;
688}
689
690/*
691 * close_stream
692 *
693 * Close control stream of session.
694 *
695 * Input parameters:
696 *   info - corresponding SessionInfo structure
697 *
698 * Output parameters:
699 *   NONE
700 *
701 */
702static void
703close_stream(FTPD_SessionInfo_t* info)
704{
705  if (NULL != info->ctrl_fp)
706  {
707    if (0 != fclose(info->ctrl_fp))
708    {
709      syslog(LOG_ERR, "ftpd: Could not close control stream: %s", serr());
710    }
711    else
712      info->ctrl_socket = -1;
713  }
714
715  if (!close_socket(info->ctrl_socket))
716    syslog(LOG_ERR, "ftpd: Could not close control socket: %s", serr());
717
718  info->ctrl_fp = NULL;
719  info->ctrl_socket = -1;
720}
721
722
723/*
724 * send_mode_reply
725 *
726 * Sends BINARY/ASCII reply string depending on current transfer mode.
727 *
728 * Input parameters:
729 *   info - corresponding SessionInfo structure
730 *
731 * Output parameters:
732 *   NONE
733 *
734 */
735static void
736send_mode_reply(FTPD_SessionInfo_t *info)
737{
738  if(info->xfer_mode == TYPE_I)
739    send_reply(info, 150, "Opening BINARY mode data connection.");
740  else
741    send_reply(info, 150, "Opening ASCII mode data connection.");
742}
743
744/*
745 * command_retrieve
746 *
747 * Perform the "RETR" command (send file to client).
748 *
749 * Input parameters:
750 *   info - corresponding SessionInfo structure
751 *   char *filename  - source filename.
752 *
753 * Output parameters:
754 *   NONE
755 *
756 */
757static void
758command_retrieve(FTPD_SessionInfo_t  *info, char const *filename)
759{
760  int                 s = -1;
761  int                 fd = -1;
762  char                buf[FTPD_DATASIZE];
763  struct stat         stat_buf;
764  int                 res = 0;
765
766  if(!can_read() || !info->auth)
767  {
768    send_reply(info, 550, "Access denied.");
769    return;
770  }
771
772  if (0 > (fd = open(filename, O_RDONLY)))
773  {
774    send_reply(info, 550, "Error opening file.");
775    return;
776  }
777
778  if (fstat(fd, &stat_buf) == 0 && S_ISDIR(stat_buf.st_mode))
779  {
780    if (-1 != fd)
781      close(fd);
782    send_reply(info, 550, "Is a directory.");
783    return;
784  }
785
786  send_mode_reply(info);
787
788  s = data_socket(info);
789
790  if (0 <= s)
791  {
792    int n = -1;
793
794    if(info->xfer_mode == TYPE_I)
795    {
796      while ((n = read(fd, buf, FTPD_DATASIZE)) > 0)
797      {
798        if(send(s, buf, n, 0) != n)
799          break;
800        yield();
801      }
802    }
803    else if (info->xfer_mode == TYPE_A)
804    {
805      int rest = 0;
806      while (rest == 0 && (n = read(fd, buf, FTPD_DATASIZE)) > 0)
807      {
808        char const* e = buf;
809        char const* b;
810        int i;
811        rest = n;
812        do
813        {
814          char lf = '\0';
815
816          b = e;
817          for(i = 0; i < rest; ++i, ++e)
818          {
819            if(*e == '\n')
820            {
821              lf = '\n';
822              break;
823            }
824          }
825          if(send(s, b, i, 0) != i)
826            break;
827          if(lf == '\n')
828          {
829            if(send(s, "\r\n", 2, 0) != 2)
830              break;
831            ++e;
832            ++i;
833          }
834        }
835        while((rest -= i) > 0);
836        yield();
837      }
838    }
839
840    if (0 == n)
841    {
842      if (0 == close(fd))
843      {
844        fd = -1;
845        res = 1;
846      }
847    }
848  }
849
850  if (-1 != fd)
851    close(fd);
852
853  if (0 == res)
854    send_reply(info, 451, "File read error.");
855  else
856    send_reply(info, 226, "Transfer complete.");
857
858  close_data_socket(info);
859
860  return;
861}
862
863
864/*
865 * discard
866 *
867 * Analog of `write' routine that just discards passed data
868 *
869 * Input parameters:
870 *   fd    - file descriptor (ignored)
871 *   buf   - data to write (ignored)
872 *   count - number of bytes in `buf'
873 *
874 * Output parameters:
875 *   returns `count'
876 *
877 */
878static ssize_t
879discard(int fd, void const* buf, size_t count)
880{
881  (void)fd;
882  (void)buf;
883  return count;
884}
885
886/*
887 * command_store
888 *
889 * Performs the "STOR" command (receive data from client).
890 *
891 * Input parameters:
892 *   info - corresponding SessionInfo structure
893 *   char *filename   - Destination filename.
894 *
895 * Output parameters:
896 *   NONE
897 */
898static void
899command_store(FTPD_SessionInfo_t *info, char const *filename)
900{
901  int                    s;
902  int                    n;
903  unsigned long          size = 0;
904  struct rtems_ftpd_hook *usehook = NULL;
905  char                   buf[FTPD_DATASIZE];
906  int                    res = 1;
907  int                    bare_lfs = 0;
908  int                    null = 0;
909  typedef ssize_t (*WriteProc)(int, void const*, size_t);
910  WriteProc              wrt = &write;
911
912  if(!can_write() || !info->auth)
913  {
914    send_reply(info, 550, "Access denied.");
915    return;
916  }
917
918  send_mode_reply(info);
919
920  s = data_socket(info);
921  if(0 > s)
922    return;
923
924  null = !strcmp("/dev/null", filename);
925  if (null)
926  {
927    /* File "/dev/null" just throws data away.
928     *  FIXME: this is hack.  Using `/dev/null' filesystem entry would be
929     *  better.
930     */
931    wrt = &discard;
932  }
933
934  if (!null && ftpd_config->hooks != NULL)
935  {
936
937    /* Search our list of hooks to see if we need to do something special. */
938    struct rtems_ftpd_hook *hook;
939    int i;
940
941    i = 0;
942    hook = &ftpd_config->hooks[i++];
943    while (hook->filename != NULL)
944    {
945      if (!strcmp(hook->filename, filename))
946      {
947        usehook = hook;
948        break;
949      }
950      hook = &ftpd_config->hooks[i++];
951    }
952  }
953
954  if (usehook != NULL)
955  {
956    /*
957     * OSV: FIXME: Small buffer could be used and hook routine
958     * called multiple times instead.  Alternatively, the support could be
959     * removed entirely in favor of configuring RTEMS pseudo-device with
960     * given name.
961     */
962
963    char   *bigBufr;
964    size_t  filesize = ftpd_config->max_hook_filesize + 1;
965
966    /*
967     * Allocate space for our "file".
968     */
969    bigBufr = (char *)malloc(filesize);
970    if (bigBufr == NULL)
971    {
972      send_reply(info, 451, "Local resource failure: malloc.");
973      close_data_socket(info);
974      return;
975    }
976
977    /*
978     * Retrieve the file into our buffer space.
979     */
980    size = 0;
981    while ((n = recv(s, bigBufr + size, filesize - size, 0)) > 0)
982    {
983      size += n;
984    }
985    if (size >= filesize)
986    {
987      send_reply(info, 451, "File too long: buffer size exceeded.");
988      free(bigBufr);
989      close_data_socket(info);
990      return;
991    }
992
993    /*
994     * Call our hook.
995     */
996    res = (usehook->hook_function)(bigBufr, size) == 0;
997    free(bigBufr);
998    if(!res)
999    {
1000      send_reply(info, 451, "File processing failed.");
1001      close_data_socket(info);
1002      return;
1003    }
1004  }
1005  else
1006  {
1007    /* Data transfer to regular file or /dev/null. */
1008    int fd = 0;
1009
1010    if(!null)
1011      fd = creat(filename,
1012        S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
1013
1014    if (0 > fd)
1015    {
1016      send_reply(info, 550, "Error creating file.");
1017      close_data_socket(info);
1018      return;
1019    }
1020
1021    if(info->xfer_mode == TYPE_I)
1022    {
1023      while ((n = recv(s, buf, FTPD_DATASIZE, 0)) > 0)
1024      {
1025        if (wrt(fd, buf, n) != n)
1026        {
1027          res = 0;
1028          break;
1029        }
1030        yield();
1031      }
1032    }
1033    else if(info->xfer_mode == TYPE_A)
1034    {
1035      int rest = 0;
1036      int pended_cr = 0;
1037      while (res && rest == 0 && (n = recv(s, buf, FTPD_DATASIZE, 0)) > 0)
1038      {
1039        char const* e = buf;
1040        char const* b;
1041        int i;
1042
1043        rest = n;
1044        if(pended_cr && *e != '\n')
1045        {
1046          char const lf = '\r';
1047          pended_cr = 0;
1048          if(wrt(fd, &lf, 1) != 1)
1049          {
1050            res = 0;
1051            break;
1052          }
1053        }
1054        do
1055        {
1056          int count;
1057          int sub = 0;
1058
1059          b = e;
1060          for(i = 0; i < rest; ++i, ++e)
1061          {
1062            int pcr = pended_cr;
1063            pended_cr = 0;
1064            if(*e == '\r')
1065            {
1066              pended_cr = 1;
1067            }
1068            else if(*e == '\n')
1069            {
1070              if(pcr)
1071              {
1072                sub = 2;
1073                ++i;
1074                ++e;
1075                break;
1076              }
1077              ++bare_lfs;
1078            }
1079          }
1080          if(res == 0)
1081            break;
1082          count = i - sub - pended_cr;
1083          if(count > 0 && wrt(fd, b, count) != count)
1084          {
1085            res = 0;
1086            break;
1087          }
1088          if(sub == 2 && wrt(fd, e - 1, 1) != 1)
1089            res = 0;
1090        }
1091        while((rest -= i) > 0);
1092        yield();
1093      }
1094    }
1095
1096    if (0 > close(fd) || res == 0)
1097    {
1098      send_reply(info, 452, "Error writing file.");
1099      close_data_socket(info);
1100      return;
1101    }
1102  }
1103
1104  if (bare_lfs > 0)
1105  {
1106    snprintf(buf, FTPD_BUFSIZE,
1107      "Transfer complete. WARNING! %d bare linefeeds received in ASCII mode.",
1108      bare_lfs);
1109    send_reply(info, 226, buf);
1110  }
1111  else
1112    send_reply(info, 226, "Transfer complete.");
1113  close_data_socket(info);
1114
1115}
1116
1117
1118/*
1119 * send_dirline
1120 *
1121 * Sends one line of LIST command reply corresponding to single file.
1122 *
1123 * Input parameters:
1124 *   s - socket descriptor to send data to
1125 *   wide - if 0, send only file name.  If not 0, send 'stat' info as well in
1126 *          "ls -l" format.
1127 *   curTime - current time
1128 *   path - path to be prepended to what is given by 'add'
1129 *   add  - path to be appended to what is given by 'path', the resulting path
1130 *          is then passed to 'stat()' routine
1131 *   name - file name to be reported in output
1132 *   buf  - buffer for temporary data
1133 *
1134 * Output parameters:
1135 *   returns false on failure, true on success
1136 *
1137 */
1138static bool
1139send_dirline(int s, bool wide, time_t curTime, char const* path,
1140  char const* add, char const* fname, char* buf)
1141{
1142  struct stat stat_buf;
1143  size_t plen = strlen(path);
1144  size_t alen = strlen(add);
1145  int slen = 0;
1146
1147  if(plen == 0)
1148  {
1149    buf[plen++] = '/';
1150    buf[plen] = '\0';
1151  }
1152  else
1153  {
1154    buf = memcpy(buf, path, plen + 1);
1155    if(alen > 0 && buf[plen - 1] != '/')
1156    {
1157      buf[plen++] = '/';
1158      if(plen >= FTPD_BUFSIZE)
1159        return 0;
1160      buf[plen] = '\0';
1161    }
1162  }
1163  if(plen + alen >= FTPD_BUFSIZE)
1164    return 0;
1165  memcpy(buf + plen, add, alen + 1);
1166
1167  if (stat(buf, &stat_buf) == 0)
1168  {
1169    if (wide)
1170    {
1171      struct tm bt;
1172      time_t tf = stat_buf.st_mtime;
1173      enum { SIZE = 80 };
1174      time_t SIX_MONTHS = (365L*24L*60L*60L)/2L;
1175      char timeBuf[SIZE];
1176      gmtime_r(&tf, &bt);
1177      if(curTime > tf + SIX_MONTHS || tf > curTime + SIX_MONTHS)
1178        strftime (timeBuf, SIZE, "%b %d  %Y", &bt);
1179      else
1180        strftime (timeBuf, SIZE, "%b %d %H:%M", &bt);
1181
1182      slen = snprintf(buf, FTPD_BUFSIZE,
1183        "%c%c%c%c%c%c%c%c%c%c  1 %5d %5d %11u %s %s\r\n",
1184        (S_ISLNK(stat_buf.st_mode)?('l'):
1185          (S_ISDIR(stat_buf.st_mode)?('d'):('-'))),
1186        (stat_buf.st_mode & S_IRUSR)?('r'):('-'),
1187        (stat_buf.st_mode & S_IWUSR)?('w'):('-'),
1188        (stat_buf.st_mode & S_IXUSR)?('x'):('-'),
1189        (stat_buf.st_mode & S_IRGRP)?('r'):('-'),
1190        (stat_buf.st_mode & S_IWGRP)?('w'):('-'),
1191        (stat_buf.st_mode & S_IXGRP)?('x'):('-'),
1192        (stat_buf.st_mode & S_IROTH)?('r'):('-'),
1193        (stat_buf.st_mode & S_IWOTH)?('w'):('-'),
1194        (stat_buf.st_mode & S_IXOTH)?('x'):('-'),
1195        (int)stat_buf.st_uid,
1196        (int)stat_buf.st_gid,
1197        (int)stat_buf.st_size,
1198        timeBuf,
1199        fname
1200      );
1201    }
1202    else
1203    {
1204      slen = snprintf(buf, FTPD_BUFSIZE, "%s\r\n", fname);
1205    }
1206  }
1207  else
1208  {
1209    slen = snprintf(buf, FTPD_BUFSIZE, "%s: %s.\r\n", fname, strerror(errno));
1210  }
1211
1212  if (slen >= FTPD_BUFSIZE)
1213  {
1214    static const char dots[] = { '.', '.', '.', '\r', '\n' };
1215
1216    /*
1217     * The file name exceeds the send buffer, indicate this with a ... at the
1218     * end of the line.
1219     */
1220    slen = FTPD_BUFSIZE - 1;
1221    memcpy(&buf[slen - sizeof(dots)], dots, sizeof(dots));
1222  }
1223
1224  if (slen > 0 && send(s, buf, (size_t) slen, 0) != slen)
1225    return false;
1226
1227  return true;
1228}
1229
1230/*
1231 * command_list
1232 *
1233 * Send file list to client.
1234 *
1235 * Input parameters:
1236 *   info - corresponding SessionInfo structure
1237 *   char *fname  - File (or directory) to list.
1238 *
1239 * Output parameters:
1240 *   NONE
1241 */
1242static void
1243command_list(FTPD_SessionInfo_t *info, char const *fname, bool wide)
1244{
1245  int                 s;
1246  DIR                 *dirp = 0;
1247  struct dirent       *dp = 0;
1248  char                buf[FTPD_BUFSIZE];
1249  time_t curTime;
1250  bool ok = true;
1251
1252  if(!info->auth)
1253  {
1254    send_reply(info, 550, "Access denied.");
1255    return;
1256  }
1257
1258  send_reply(info, 150, "Opening ASCII mode data connection for LIST.");
1259
1260  s = data_socket(info);
1261  if(0 > s)
1262  {
1263    syslog(LOG_ERR, "ftpd: Error connecting to data socket.");
1264    return;
1265  }
1266
1267  if (fname[0] == '\0')
1268    fname = ".";
1269
1270  time(&curTime);
1271  dirp = opendir(fname);
1272  if (dirp != NULL)
1273  {
1274    /* FIXME: need "." and ".." only when '-a' option is given */
1275    ok = ok && send_dirline(s, wide, curTime, fname, "", ".", buf);
1276    ok = ok && send_dirline(s, wide, curTime, fname,
1277      (strcmp(fname, ftpd_root) ? ".." : ""), "..", buf);
1278
1279    while (ok && (dp = readdir(dirp)) != NULL)
1280      ok = ok &&
1281        send_dirline(s, wide, curTime, fname, dp->d_name, dp->d_name, buf);
1282
1283    closedir(dirp);
1284  }
1285  else
1286  {
1287    send_dirline(s, wide, curTime, fname, "", fname, buf);
1288  }
1289
1290  close_data_socket(info);
1291
1292  if (ok)
1293    send_reply(info, 226, "Transfer complete.");
1294  else
1295    send_reply(info, 426, "Connection aborted.");
1296}
1297
1298
1299/*
1300 * command_cwd
1301 *
1302 * Change current working directory.
1303 *
1304 * Input parameters:
1305 *   info - corresponding SessionInfo structure
1306 *   dir  - directory name passed in CWD command
1307 *
1308 * Output parameters:
1309 *   NONE
1310 *
1311 */
1312static void
1313command_cwd(FTPD_SessionInfo_t  *info, const char *dir)
1314{
1315  if(!info->auth)
1316  {
1317    send_reply(info, 550, "Access denied.");
1318    return;
1319  }
1320
1321  if(chdir(dir) == 0)
1322    send_reply(info, 250, "CWD command successful.");
1323  else
1324    send_reply(info, 550, "CWD command failed.");
1325}
1326
1327
1328/*
1329 * command_pwd
1330 *
1331 * Send current working directory to client.
1332 *
1333 * Input parameters:
1334 *   info - corresponding SessionInfo structure
1335 *
1336 * Output parameters:
1337 *   NONE
1338 */
1339static void
1340command_pwd(FTPD_SessionInfo_t  *info)
1341{
1342  char buf[FTPD_BUFSIZE];
1343  char const* cwd;
1344  errno = 0;
1345  buf[0] = '"';
1346
1347  if(!info->auth)
1348  {
1349    send_reply(info, 550, "Access denied.");
1350    return;
1351  }
1352
1353  cwd = getcwd(buf + 1, FTPD_BUFSIZE - 4);
1354  if(cwd)
1355  {
1356    int len = strlen(cwd);
1357    static char const txt[] = "\" is the current directory.";
1358    int size = sizeof(txt);
1359    if(len + size + 1 >= FTPD_BUFSIZE)
1360      size = FTPD_BUFSIZE - len - 2;
1361    memcpy(buf + len + 1, txt, size);
1362    buf[len + size] = '\0';
1363    send_reply(info, 250, buf);
1364  }
1365  else {
1366    snprintf(buf, FTPD_BUFSIZE, "Error: %s.", serr());
1367    send_reply(info, 452, buf);
1368  }
1369}
1370
1371/*
1372 * command_mdtm
1373 *
1374 * Handle FTP MDTM command (send file modification time to client)/
1375 *
1376 * Input parameters:
1377 *   info - corresponding SessionInfo structure
1378 *   fname - file name passed in MDTM command
1379 *
1380 * Output parameters:
1381 *   info->cwd is set to new CWD value.
1382 */
1383static void
1384command_mdtm(FTPD_SessionInfo_t  *info, char const* fname)
1385{
1386  struct stat stbuf;
1387  char buf[FTPD_BUFSIZE];
1388
1389  if(!info->auth)
1390  {
1391    send_reply(info, 550, "Access denied.");
1392    return;
1393  }
1394
1395  if (0 > stat(fname, &stbuf))
1396  {
1397    snprintf(buf, FTPD_BUFSIZE, "%s: %s.", fname, serr());
1398    send_reply(info, 550, buf);
1399  }
1400  else
1401  {
1402    struct tm *t = gmtime(&stbuf.st_mtime);
1403    snprintf(buf, FTPD_BUFSIZE, "%04d%02d%02d%02d%02d%02d",
1404      1900 + t->tm_year,
1405      t->tm_mon+1, t->tm_mday,
1406      t->tm_hour, t->tm_min, t->tm_sec);
1407    send_reply(info, 213, buf);
1408  }
1409}
1410
1411static void
1412command_size(FTPD_SessionInfo_t *info, char const* fname)
1413{
1414  struct stat stbuf;
1415  char buf[FTPD_BUFSIZE];
1416
1417  if(!info->auth)
1418  {
1419    send_reply(info, 550, "Access denied.");
1420    return;
1421  }
1422
1423  if (info->xfer_mode != TYPE_I || 0 > stat(fname, &stbuf) || stbuf.st_size < 0)
1424  {
1425    send_reply(info, 550, "Could not get file size.");
1426  }
1427  else
1428  {
1429    snprintf(buf, FTPD_BUFSIZE, "%" PRIuMAX, (uintmax_t) stbuf.st_size);
1430    send_reply(info, 213, buf);
1431  }
1432}
1433
1434/*
1435 * command_port
1436 *
1437 * This procedure fills address for data connection given the IP address and
1438 * port of the remote machine.
1439 *
1440 * Input parameters:
1441 *   info - corresponding SessionInfo structure
1442 *   args - arguments to the "PORT" command.
1443 *
1444 * Output parameters:
1445 *   info->data_addr is set according to arguments of the PORT command.
1446 *   info->use_default is set to 0 on success, 1 on failure.
1447 */
1448static void
1449command_port(FTPD_SessionInfo_t *info, char const *args)
1450{
1451  enum { NUM_FIELDS = 6 };
1452  unsigned int a[NUM_FIELDS];
1453  int n;
1454
1455  close_data_socket(info);
1456
1457  n = sscanf(args, "%u,%u,%u,%u,%u,%u", a+0, a+1, a+2, a+3, a+4, a+5);
1458  if(NUM_FIELDS == n)
1459  {
1460    int i;
1461    union {
1462      uint8_t b[NUM_FIELDS];
1463      struct {
1464        uint32_t ip;
1465        uint16_t port;
1466      } u ;
1467    } ip_info;
1468
1469    for(i = 0; i < NUM_FIELDS; ++i)
1470    {
1471      if(a[i] > 255)
1472        break;
1473      ip_info.b[i] = (uint8_t)a[i];
1474    }
1475
1476    if(i == NUM_FIELDS)
1477    {
1478      /* Note: while it contradicts RFC959, we don't allow PORT command
1479       * to specify IP address different from that of the originating client
1480       * for the sake of safety. */
1481      if (ip_info.u.ip == info->def_addr.sin_addr.s_addr)
1482      {
1483        info->data_addr.sin_addr.s_addr = ip_info.u.ip;
1484        info->data_addr.sin_port        = ip_info.u.port;
1485        info->data_addr.sin_family      = AF_INET;
1486        memset(info->data_addr.sin_zero, 0, sizeof(info->data_addr.sin_zero));
1487
1488        info->use_default = 0;
1489        send_reply(info, 200, "PORT command successful.");
1490        return; /* success */
1491      }
1492      else
1493      {
1494        send_reply(info, 425, "Address doesn't match peer's IP.");
1495        return;
1496      }
1497    }
1498  }
1499  send_reply(info, 501, "Syntax error.");
1500}
1501
1502
1503/*
1504 * command_pasv
1505 *
1506 * Handle FTP PASV command.
1507 * Open socket, listen for and accept connection on it.
1508 *
1509 * Input parameters:
1510 *   info - corresponding SessionInfo structure
1511 *
1512 * Output parameters:
1513 *   info->pasv_socket is set to the descriptor of the data socket
1514 */
1515static void
1516command_pasv(FTPD_SessionInfo_t *info)
1517{
1518  int s = -1;
1519  int err = 1;
1520
1521  close_data_socket(info);
1522
1523  s = socket(PF_INET, SOCK_STREAM, 0);
1524  if (s < 0)
1525    syslog(LOG_ERR, "ftpd: Error creating PASV socket: %s", serr());
1526  else
1527  {
1528    struct sockaddr_in addr;
1529    socklen_t addrLen = sizeof(addr);
1530
1531    addr = info->ctrl_addr;
1532    addr.sin_port = htons(0);
1533
1534    if (0 > bind(s, (struct sockaddr *)&addr, addrLen))
1535      syslog(LOG_ERR, "ftpd: Error binding PASV socket: %s", serr());
1536    else if (0 > listen(s, 1))
1537      syslog(LOG_ERR, "ftpd: Error listening on PASV socket: %s", serr());
1538    else if (set_socket_timeout(s, info->idle))
1539    {
1540      if (0 == getsockname(s, (struct sockaddr *)&addr, &addrLen))
1541      {
1542        char buf[FTPD_BUFSIZE];
1543        unsigned char const *ip, *p;
1544
1545        ip = (unsigned char const*)&(addr.sin_addr);
1546        p  = (unsigned char const*)&(addr.sin_port);
1547        snprintf(buf, FTPD_BUFSIZE, "Entering passive mode (%u,%u,%u,%u,%u,%u).",
1548          ip[0], ip[1], ip[2], ip[3], p[0], p[1]);
1549        send_reply(info, 227, buf);
1550
1551        info->pasv_socket = accept(s, (struct sockaddr *)&addr, &addrLen);
1552        if (0 > info->pasv_socket)
1553          syslog(LOG_ERR, "ftpd: Error accepting PASV connection: %s", serr());
1554        else
1555        {
1556          close_socket(s);
1557          s = -1;
1558          err = 0;
1559        }
1560      }
1561      else
1562        syslog(LOG_ERR, "ftpd: Cannot get socket name: %s", serr());
1563    }
1564  }
1565  if(err)
1566  {
1567    /* (OSV) The note is from FreeBSD FTPD.
1568     * Note: a response of 425 is not mentioned as a possible response to
1569     * the PASV command in RFC959.  However, it has been blessed as a
1570     * legitimate response by Jon Postel in a telephone conversation
1571     * with Rick Adams on 25 Jan 89. */
1572    send_reply(info, 425, "Can't open passive connection.");
1573    close_socket(s);
1574  }
1575}
1576
1577
1578/*
1579 * skip_options
1580 *
1581 * Utility routine to skip options (if any) from input command.
1582 *
1583 * Input parameters:
1584 *   p  - pointer to pointer to command
1585 *
1586 * Output parameters:
1587 *   p  - is changed to point to first non-option argument
1588 */
1589static void
1590skip_options(char **p)
1591{
1592  char* buf = *p;
1593  char* last = NULL;
1594  while(1) {
1595    while(isspace((unsigned char)*buf))
1596      ++buf;
1597    if(*buf == '-') {
1598      if(*++buf == '-') { /* `--' should terminate options */
1599        if(isspace((unsigned char)*++buf)) {
1600          last = buf;
1601          do ++buf;
1602          while(isspace((unsigned char)*buf));
1603          break;
1604        }
1605      }
1606      while(*buf && !isspace((unsigned char)*buf))
1607        ++buf;
1608      last = buf;
1609    }
1610    else
1611      break;
1612  }
1613  if(last)
1614    *last = '\0';
1615  *p = buf;
1616}
1617
1618/*
1619 * split_command
1620 *
1621 * Split command into command itself, options, and arguments. Command itself
1622 * is converted to upper case.
1623 *
1624 * Input parameters:
1625 *   buf - initial command string
1626 *
1627 * Output parameter:
1628 *   buf  - is modified by inserting '\0' at ends of split entities
1629 *   cmd  - upper-cased command code
1630 *   opts - string containing all the options
1631 *   args - string containing all the arguments
1632 */
1633static void
1634split_command(char *buf, char **cmd, char **opts, char **args)
1635{
1636  char* eoc;
1637  char* p = buf;
1638  while(isspace((unsigned char)*p))
1639    ++p;
1640  *cmd = p;
1641  while(*p && !isspace((unsigned char)*p))
1642  {
1643    *p = toupper((unsigned char)*p);
1644    ++p;
1645  }
1646  eoc = p;
1647  if(*p)
1648    *p++ = '\0';
1649  while(isspace((unsigned char)*p))
1650    ++p;
1651  *opts = p;
1652  skip_options(&p);
1653  *args = p;
1654  if(*opts == p)
1655    *opts = eoc;
1656  while(*p && *p != '\r' && *p != '\n')
1657    ++p;
1658  if(*p)
1659    *p++ = '\0';
1660}
1661
1662/*
1663 * exec_command
1664 *
1665 * Parse and execute FTP command.
1666 *
1667 * FIXME: This section is somewhat of a hack.  We should have a better
1668 *        way to parse commands.
1669 *
1670 * Input parameters:
1671 *   info - corresponding SessionInfo structure
1672 *   cmd  - command to be executed (upper-case)
1673 *   args - arguments of the command
1674 *
1675 * Output parameters:
1676 *    NONE
1677 */
1678static void
1679exec_command(FTPD_SessionInfo_t *info, char *cmd, char *args)
1680{
1681  int wrong_command = 0;
1682
1683  if (!strcmp("PORT", cmd))
1684  {
1685    command_port(info, args);
1686  }
1687  else if (!strcmp("PASV", cmd))
1688  {
1689    command_pasv(info);
1690  }
1691  else if (!strcmp("RETR", cmd))
1692  {
1693    command_retrieve(info, args);
1694  }
1695  else if (!strcmp("STOR", cmd))
1696  {
1697    command_store(info, args);
1698  }
1699  else if (!strcmp("LIST", cmd))
1700  {
1701    command_list(info, args, true);
1702  }
1703  else if (!strcmp("NLST", cmd))
1704  {
1705    command_list(info, args, false);
1706  }
1707  else if (!strcmp("MDTM", cmd))
1708  {
1709    command_mdtm(info, args);
1710  }
1711  else if (!strcmp("SIZE", cmd))
1712  {
1713    command_size(info, args);
1714  }
1715  else if (!strcmp("SYST", cmd))
1716  {
1717    send_reply(info, 215, FTPD_SYSTYPE);
1718  }
1719  else if (!strcmp("TYPE", cmd))
1720  {
1721    if (args[0] == 'I')
1722    {
1723      info->xfer_mode = TYPE_I;
1724      send_reply(info, 200, "Type set to I.");
1725    }
1726    else if (args[0] == 'A')
1727    {
1728      info->xfer_mode = TYPE_A;
1729      send_reply(info, 200, "Type set to A.");
1730    }
1731    else
1732    {
1733      info->xfer_mode = TYPE_I;
1734      send_reply(info, 504, "Type not implemented.  Set to I.");
1735    }
1736  }
1737  else if (!strcmp("USER", cmd))
1738  {
1739    strlcpy(info->user_buf, args, sizeof(info->user_buf));
1740    info->user = info->user_buf;
1741    if (ftpd_config->login &&
1742      !ftpd_config->login(info->user, NULL)) {
1743      info->auth = false;
1744      send_reply(info, 331, "User name okay, need password.");
1745    } else {
1746      info->auth = true;
1747      send_reply(info, 230, "User logged in.");
1748    }
1749  }
1750  else if (!strcmp("PASS", cmd))
1751  {
1752    if (!info->user) {
1753      send_reply(info, 332, "Need account to log in");
1754    } else {
1755      if (ftpd_config->login &&
1756        !ftpd_config->login(info->user, args)) {
1757        info->auth = false;
1758        send_reply(info, 530, "Not logged in.");
1759      } else {
1760        info->auth = true;
1761        send_reply(info, 230, "User logged in.");
1762      }
1763    }
1764  }
1765  else if (!strcmp("DELE", cmd))
1766  {
1767    if(!can_write() || !info->auth)
1768    {
1769      send_reply(info, 550, "Access denied.");
1770    }
1771    else if (unlink(args) == 0)
1772    {
1773      send_reply(info, 257, "DELE successful.");
1774    }
1775    else
1776    {
1777      send_reply(info, 550, "DELE failed.");
1778    }
1779  }
1780  else if (!strcmp("SITE", cmd))
1781  {
1782    char* opts;
1783    split_command(args, &cmd, &opts, &args);
1784    if(!strcmp("CHMOD", cmd))
1785    {
1786      int mask;
1787
1788      if(!can_write() || !info->auth)
1789      {
1790        send_reply(info, 550, "Access denied.");
1791      }
1792      else {
1793        char *c;
1794        c = strchr(args, ' ');
1795        if((c != NULL) && (sscanf(args, "%o", &mask) == 1)
1796          && (chmod(c + 1, (mode_t)mask) == 0))
1797          send_reply(info, 257, "CHMOD successful.");
1798        else
1799          send_reply(info, 550, "CHMOD failed.");
1800      }
1801    }
1802    else
1803      wrong_command = 1;
1804  }
1805  else if (!strcmp("RMD", cmd))
1806  {
1807    if(!can_write() || !info->auth)
1808    {
1809      send_reply(info, 550, "Access denied.");
1810    }
1811    else if (rmdir(args) == 0)
1812    {
1813      send_reply(info, 257, "RMD successful.");
1814    }
1815    else
1816    {
1817      send_reply(info, 550, "RMD failed.");
1818    }
1819  }
1820  else if (!strcmp("MKD", cmd))
1821  {
1822    if(!can_write() || !info->auth)
1823    {
1824      send_reply(info, 550, "Access denied.");
1825    }
1826    else if (mkdir(args, S_IRWXU | S_IRWXG | S_IRWXO) == 0)
1827    {
1828      send_reply(info, 257, "MKD successful.");
1829    }
1830    else
1831    {
1832      send_reply(info, 550, "MKD failed.");
1833    }
1834  }
1835  else if (!strcmp("CWD", cmd))
1836  {
1837    command_cwd(info, args);
1838  }
1839  else if (!strcmp("CDUP", cmd))
1840  {
1841    command_cwd(info, "..");
1842  }
1843  else if (!strcmp("PWD", cmd))
1844  {
1845    command_pwd(info);
1846  }
1847  else
1848    wrong_command = 1;
1849
1850  if(wrong_command)
1851    send_reply(info, 500, "Command not understood.");
1852}
1853
1854
1855/*
1856 * session
1857 *
1858 * This task handles single session.  It is woken up when the FTP daemon gets a
1859 * service request from a remote machine.  Here, we watch for commands that
1860 * will come through the control connection.  These commands are then parsed
1861 * and executed until the connection is closed, either unintentionally or
1862 * intentionally with the "QUIT" command.
1863 *
1864 * Input parameters:
1865 *   arg - pointer to corresponding SessionInfo.
1866 *
1867 * Output parameters:
1868 *   NONE
1869 */
1870static void
1871session(rtems_task_argument arg)
1872{
1873  FTPD_SessionInfo_t  *const info = (FTPD_SessionInfo_t  *)arg;
1874  bool chroot_made = false;
1875
1876  while (1)
1877  {
1878    rtems_event_set set;
1879
1880    rtems_event_receive(FTPD_RTEMS_EVENT, RTEMS_EVENT_ANY, RTEMS_NO_TIMEOUT,
1881      &set);
1882
1883    chroot_made = chroot_made
1884      || (rtems_libio_set_private_env() == RTEMS_SUCCESSFUL
1885        && chroot(ftpd_root) == 0);
1886
1887    /*
1888     * The chdir() must immediately follow the chroot(), otherwise static
1889     * analysis tools may complain about a security issue.
1890     */
1891
1892    if (chroot_made && chdir("/") == 0)
1893    {
1894      send_reply(info, 220, FTPD_SERVER_MESSAGE);
1895
1896      while (1)
1897      {
1898        char buf[FTPD_BUFSIZE];
1899        char *cmd, *opts, *args;
1900        size_t len;
1901
1902        if (fgets(buf, FTPD_BUFSIZE, info->ctrl_fp) == NULL)
1903        {
1904          syslog(LOG_INFO, "ftpd: Connection aborted.");
1905          break;
1906        }
1907
1908        len = strlen(buf);
1909
1910        if (len == 0)
1911          continue;
1912
1913        if (buf[len - 1] != '\n')
1914        {
1915          send_reply(info, 501, "Command line too long.");
1916
1917          /*
1918           * We could also try to continue here; however, discarding the rest
1919           * of the current command line and figuring out when the next command
1920           * starts with fgets() is not that easy.  It would be better to avoid
1921           * the FILE stream and just use the socket directly with send() and
1922           * recv().
1923           */
1924          break;
1925        }
1926
1927        split_command(buf, &cmd, &opts, &args);
1928
1929        if (!strcmp("QUIT", cmd))
1930        {
1931          send_reply(info, 221, "Goodbye.");
1932          break;
1933        }
1934        else
1935        {
1936          exec_command(info, cmd, args);
1937        }
1938      }
1939    }
1940    else
1941    {
1942      send_reply(info, 421, "Service not available, closing control connection.");
1943    }
1944
1945    /*
1946     * Go back to the root directory.  A use case is to release a current
1947     * directory in a mounted file system on dynamic media, e.g. USB stick.
1948     * The return value can be ignored since the next session will try do the
1949     * operation again and an error check is performed in this case.
1950     */
1951    chdir("/");
1952
1953    /* Close connection and put ourselves back into the task pool. */
1954    close_data_socket(info);
1955    close_stream(info);
1956    task_pool_release(info);
1957  }
1958}
1959
1960
1961/*
1962 * ftpd_daemon
1963 *
1964 * This task runs forever.  It waits for service requests on the FTP port
1965 * (port 21 by default).  When a request is received, it opens a new session
1966 * to handle those requests until the connection is closed.
1967 *
1968 * Input parameters:
1969 *   NONE
1970 *
1971 * Output parameters:
1972 *   NONE
1973 */
1974static void
1975ftpd_daemon(rtems_task_argument args RTEMS_UNUSED)
1976{
1977  int                 s;
1978  socklen_t           addrLen;
1979  struct sockaddr_in  addr;
1980
1981  memset(&addr, 0, sizeof(addr));
1982  addr.sin_family      = AF_INET;
1983  addr.sin_port        = htons(ftpd_config->port);
1984  addr.sin_addr.s_addr = htonl(INADDR_ANY);
1985
1986  s = socket(PF_INET, SOCK_STREAM, 0);
1987  if (s < 0)
1988    syslog(LOG_ERR, "ftpd: Error creating control socket: %s", serr());
1989  else if (0 > bind(s, (struct sockaddr *)&addr, sizeof(addr)))
1990    syslog(LOG_ERR, "ftpd: Error binding control socket: %s", serr());
1991  else if (0 > listen(s, 1))
1992    syslog(LOG_ERR, "ftpd: Error listening on control socket: %s", serr());
1993  else while (1)
1994  {
1995    int ss;
1996    addrLen = sizeof(addr);
1997    ss = accept(s, (struct sockaddr *)&addr, &addrLen);
1998    if (0 > ss)
1999      syslog(LOG_ERR, "ftpd: Error accepting control connection: %s", serr());
2000    else if(!set_socket_timeout(ss, ftpd_timeout))
2001      close_socket(ss);
2002    else
2003    {
2004      FTPD_SessionInfo_t *info;
2005
2006      info = task_pool_obtain();
2007      if (NULL == info)
2008      {
2009        close_socket(ss);
2010      }
2011      else
2012      {
2013        info->ctrl_socket = ss;
2014        if ((info->ctrl_fp = fdopen(info->ctrl_socket, "r+")) == NULL)
2015        {
2016          syslog(LOG_ERR, "ftpd: fdopen() on socket failed: %s", serr());
2017          close_stream(info);
2018          task_pool_release(info);
2019        }
2020        else
2021        {
2022          /* Initialize corresponding SessionInfo structure */
2023          info->def_addr = addr;
2024          if(0 > getsockname(ss, (struct sockaddr *)&addr, &addrLen))
2025          {
2026            syslog(LOG_ERR, "ftpd: getsockname(): %s", serr());
2027            close_stream(info);
2028            task_pool_release(info);
2029          }
2030          else
2031          {
2032            info->use_default = 1;
2033            info->ctrl_addr  = addr;
2034            info->pasv_socket = -1;
2035            info->data_socket = -1;
2036            info->xfer_mode   = TYPE_A;
2037            info->data_addr.sin_port =
2038              htons(ntohs(info->ctrl_addr.sin_port) - 1);
2039            info->idle = ftpd_timeout;
2040            info->user = NULL;
2041            if (ftpd_config->login)
2042              info->auth = false;
2043            else
2044              info->auth = true;
2045            /* Wakeup the session task.  The task will call task_pool_release
2046               after it closes connection. */
2047            rtems_event_send(info->tid, FTPD_RTEMS_EVENT);
2048          }
2049        }
2050      }
2051    }
2052  }
2053
2054  close(s);
2055  rtems_task_exit();
2056}
2057
2058
2059/*
2060 * rtems_ftpd_start
2061 *
2062 * Here, we start the FTPD task which waits for FTP requests and services
2063 * them.  This procedure returns to its caller once the task is started.
2064 *
2065 *
2066 * Input parameters:
2067 *    config: constant initial setup.
2068 * Output parameters:
2069 *    returns RTEMS_SUCCESSFUL on successful start of the daemon.
2070 */
2071int
2072rtems_ftpd_start(const struct rtems_ftpd_configuration* config)
2073{
2074  rtems_status_code   sc;
2075  rtems_id            tid;
2076  rtems_task_priority priority;
2077  int count;
2078
2079  if (ftpd_config != NULL)
2080    return RTEMS_RESOURCE_IN_USE;
2081
2082  ftpd_config = malloc(sizeof(*ftpd_config));
2083  if (ftpd_config == NULL)
2084    return RTEMS_NO_MEMORY;
2085
2086  *ftpd_config = *config;
2087
2088  if (ftpd_config->port == 0)
2089  {
2090    ftpd_config->port = FTPD_CONTROL_PORT;
2091  }
2092
2093  if (ftpd_config->priority == 0)
2094  {
2095    ftpd_config->priority = 40;
2096  }
2097  priority = ftpd_config->priority;
2098
2099  ftpd_timeout = ftpd_config->idle;
2100  if (ftpd_timeout < 0)
2101    ftpd_timeout = 0;
2102  ftpd_config->idle = ftpd_timeout;
2103
2104  ftpd_access = ftpd_config->access;
2105
2106  ftpd_root = "/";
2107  if (ftpd_config->root && ftpd_config->root[0] == '/' )
2108    ftpd_root = ftpd_config->root;
2109
2110  ftpd_config->root = ftpd_root;
2111
2112  if (ftpd_config->tasks_count <= 0)
2113    ftpd_config->tasks_count = 1;
2114  count = ftpd_config->tasks_count;
2115
2116  if (!task_pool_init(count, priority))
2117  {
2118    syslog(LOG_ERR, "ftpd: Could not initialize task pool.");
2119    return RTEMS_UNSATISFIED;
2120  }
2121
2122  sc = rtems_task_create(rtems_build_name('F', 'T', 'P', 'D'),
2123    priority, RTEMS_MINIMUM_STACK_SIZE,
2124    RTEMS_PREEMPT | RTEMS_NO_TIMESLICE | RTEMS_NO_ASR |
2125    RTEMS_INTERRUPT_LEVEL(0),
2126    RTEMS_FLOATING_POINT | RTEMS_LOCAL,
2127    &tid);
2128
2129  if (sc == RTEMS_SUCCESSFUL)
2130  {
2131    sc = rtems_task_start(tid, ftpd_daemon, 0);
2132    if (sc != RTEMS_SUCCESSFUL)
2133      rtems_task_delete(tid);
2134  }
2135
2136  if (sc != RTEMS_SUCCESSFUL)
2137  {
2138    task_pool_done(count);
2139    syslog(LOG_ERR, "ftpd: Could not create/start FTP daemon: %s",
2140      rtems_status_text(sc));
2141    return RTEMS_UNSATISFIED;
2142  }
2143
2144  if (ftpd_config->verbose)
2145    syslog(LOG_INFO, "ftpd: FTP daemon started (%d session%s max)",
2146           count, ((count > 1) ? "s" : ""));
2147
2148  return RTEMS_SUCCESSFUL;
2149}
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