aboutsummaryrefslogtreecommitdiff
path: root/lib/tftp.c
blob: 891871d87b9a57feba7a4fb340149d502080b813 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
/***************************************************************************
 *                                  _   _ ____  _
 *  Project                     ___| | | |  _ \| |
 *                             / __| | | | |_) | |
 *                            | (__| |_| |  _ <| |___
 *                             \___|\___/|_| \_\_____|
 *
 * Copyright (C) 1998 - 2005, Daniel Stenberg, <daniel@haxx.se>, et al.
 *
 * This software is licensed as described in the file COPYING, which
 * you should have received as part of this distribution. The terms
 * are also available at http://curl.haxx.se/docs/copyright.html.
 *
 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
 * copies of the Software, and permit persons to whom the Software is
 * furnished to do so, under the terms of the COPYING file.
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
 * KIND, either express or implied.
 *
 * $Id$
 ***************************************************************************/

#include "setup.h"

#ifndef CURL_DISABLE_TFTP
/* -- WIN32 approved -- */
#include <stdio.h>
#include <string.h>
#include <stdarg.h>
#include <stdlib.h>
#include <ctype.h>
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif
#include <errno.h>

#if defined(WIN32)
#include <time.h>
#include <io.h>
#else
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#include <netinet/in.h>
#include <sys/time.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <netdb.h>
#ifdef HAVE_ARPA_INET_H
#include <arpa/inet.h>
#endif
#ifdef HAVE_NET_IF_H
#include <net/if.h>
#endif
#include <sys/ioctl.h>
#include <signal.h>

#ifdef HAVE_SYS_PARAM_H
#include <sys/param.h>
#endif


#endif

#include "urldata.h"
#include <curl/curl.h>
#include "transfer.h"
#include "sendf.h"
#include "tftp.h"
#include "progress.h"
#include "connect.h"
#include "strerror.h"

#define _MPRINTF_REPLACE /* use our functions only */
#include <curl/mprintf.h>

#include "memory.h"
#include "select.h"

/* The last #include file should be: */
#include "memdebug.h"

#ifndef MSG_NOSIGNAL
#define MSG_NOSIGNAL 0
#endif

typedef enum {
  TFTP_MODE_NETASCII=0,
  TFTP_MODE_OCTET
} tftp_mode_t;

typedef enum {
  TFTP_STATE_START=0,
  TFTP_STATE_RX,
  TFTP_STATE_TX,
  TFTP_STATE_FIN
} tftp_state_t;

typedef enum {
  TFTP_EVENT_INIT=0,
  TFTP_EVENT_RRQ = 1,
  TFTP_EVENT_WRQ = 2,
  TFTP_EVENT_DATA = 3,
  TFTP_EVENT_ACK = 4,
  TFTP_EVENT_ERROR = 5,
  TFTP_EVENT_TIMEOUT
} tftp_event_t;

typedef enum {
  TFTP_ERR_UNDEF=0,
  TFTP_ERR_NOTFOUND,
  TFTP_ERR_PERM,
  TFTP_ERR_DISKFULL,
  TFTP_ERR_ILLEGAL,
  TFTP_ERR_UNKNOWNID,
  TFTP_ERR_EXISTS,
  TFTP_ERR_NOSUCHUSER,
  TFTP_ERR_TIMEOUT,
  TFTP_ERR_NORESPONSE
} tftp_error_t;

typedef struct tftp_packet {
  unsigned short  event;
  union {
    struct {
      unsigned char   data[512];
    } request;
    struct {
      unsigned short  block;
      unsigned char   data[512];
    } data;
    struct {
      unsigned short  block;
    } ack;
    struct {
      unsigned short  code;
      unsigned char   data[512];
    } error;
  } u;
} tftp_packet_t;

typedef struct tftp_state_data {
  tftp_state_t    state;
  tftp_mode_t     mode;
  tftp_error_t    error;
  struct connectdata      *conn;
  curl_socket_t   sockfd;
  int             retries;
  int             retry_time;
  int             retry_max;
  time_t          start_time;
  time_t          max_time;
  unsigned short  block;
  struct sockaddr local_addr;
  socklen_t       local_addrlen;
  struct sockaddr remote_addr;
  socklen_t       remote_addrlen;
  int             rbytes;
  int             sbytes;
  tftp_packet_t   rpacket;
  tftp_packet_t   spacket;
} tftp_state_data_t;


/* Forward declarations */
static void tftp_rx(tftp_state_data_t *state, tftp_event_t event) ;
static void tftp_tx(tftp_state_data_t *state, tftp_event_t event) ;
void tftp_set_timeouts(tftp_state_data_t *state) ;

/**********************************************************
 *
 * tftp_set_timeouts -
 *
 * Set timeouts based on state machine state.
 * Use user provided connect timeouts until DATA or ACK
 * packet is received, then use user-provided transfer timeouts
 *
 *
 **********************************************************/
void tftp_set_timeouts(tftp_state_data_t *state)
{

  struct SessionHandle *data = state->conn->data;
  unsigned long         maxtime, timeout;

  time(&state->start_time);
  if(state->state == TFTP_STATE_START) {
    /* Compute drop-dead time */
    maxtime = data->set.connecttimeout?data->set.connecttimeout:30;
    state->max_time = state->start_time+maxtime;

    /* Set per-block timeout to total */
    timeout = maxtime ;

    /* Average restart after 5 seconds */
    state->retry_max = timeout/5;

    /* Compute the re-start interval to suit the timeout */
    state->retry_time = timeout/state->retry_max;
    if(state->retry_time<1) state->retry_time=1;

  }
  else {

    /* Compute drop-dead time */
    maxtime = data->set.timeout?data->set.timeout:3600;
    state->max_time = state->start_time+maxtime;

    /* Set per-block timeout to 10% of total */
    timeout = maxtime/10 ;

    /* Average reposting an ACK after 15 seconds */
    state->retry_max = timeout/15;
  }
  /* But bound the total number  */
  if(state->retry_max<3) state->retry_max=3;
  if(state->retry_max>50) state->retry_max=50;

  /* Compute the re-ACK interval to suit the timeout */
  state->retry_time = timeout/state->retry_max;
  if(state->retry_time<1) state->retry_time=1;

  infof(data, "set timeouts for state %d; Total %d, retry %d maxtry %d\n",
        state->state, (state->max_time-state->start_time),
        state->retry_time, state->retry_max);
}

/**********************************************************
 *
 * tftp_set_send_first
 *
 * Event handler for the START state
 *
 **********************************************************/

static void tftp_send_first(tftp_state_data_t *state, tftp_event_t event)
{
  int sbytes;
  const char *mode = "octet";
  char *filename = state->conn->path;
  struct SessionHandle *data = state->conn->data;

  /* Set ascii mode if -B flag was used */
  if(data->set.ftp_ascii)
    mode = "netascii";

  switch(event) {

  case TFTP_EVENT_INIT:    /* Send the first packet out */
  case TFTP_EVENT_TIMEOUT: /* Resend the first packet out */
    /* Increment the retry counter, quit if over the limit */
    state->retries++;
    if(state->retries>state->retry_max) {
      state->error = TFTP_ERR_NORESPONSE;
      state->state = TFTP_STATE_FIN;
      return;
    }

    if(data->set.upload) {
      /* If we are uploading, send an WRQ */
      state->spacket.event = htons(TFTP_EVENT_WRQ);
      filename = curl_unescape(filename, strlen(filename));
      state->conn->upload_fromhere = (char *)state->spacket.u.data.data;
      if(data->set.infilesize != -1) {
        Curl_pgrsSetUploadSize(data, data->set.infilesize);
      }
    }
    else {
      /* If we are downloading, send an RRQ */
      state->spacket.event = htons(TFTP_EVENT_RRQ);
    }
    sprintf((char *)state->spacket.u.request.data, "%s%c%s%c",
            filename, '\0',  mode, '\0');
    sbytes = 4 + strlen(filename) + strlen(mode);
    sbytes = sendto(state->sockfd, &state->spacket, sbytes, 0,
                    state->conn->ip_addr->ai_addr,
                    state->conn->ip_addr->ai_addrlen);
    if(sbytes < 0) {
      failf(data, "%s\n", strerror(errno));
    }
    break;

  case TFTP_EVENT_ACK: /* Connected for transmit */
    infof(data, "%s\n", "Connected for transmit");
    state->state = TFTP_STATE_TX;
    tftp_set_timeouts(state);
    tftp_tx(state, event);
    break;

  case TFTP_EVENT_DATA: /* connected for receive */
    infof(data, "%s\n", "Connected for receive");
    state->state = TFTP_STATE_RX;
    tftp_set_timeouts(state);
    tftp_rx(state, event);
    break;

  case TFTP_EVENT_ERROR:
    state->state = TFTP_STATE_FIN;
    break;

  default:
    failf(state->conn->data, "tftp_send_first: internal error\n");
    break;
  }
}

/**********************************************************
 *
 * tftp_rx
 *
 * Event handler for the RX state
 *
 **********************************************************/
static void tftp_rx(tftp_state_data_t *state, tftp_event_t event)
{
  int sbytes;
  int rblock;
  struct SessionHandle *data = state->conn->data;

  switch(event) {

  case TFTP_EVENT_DATA:

    /* Is this the block we expect? */
    rblock = ntohs(state->rpacket.u.data.block);
    if ((state->block+1) != rblock) {
      /* No, log it, up the retry count and fail if over the limit */
      infof(data,
            "Received unexpected DATA packet block %d\n", rblock);
      state->retries++;
      if (state->retries>state->retry_max) {
        failf(data, "tftp_rx: giving up waiting for block %d\n",
              state->block+1);
        return;
      }
    }
    /* This is the expected block.  Reset counters and ACK it. */
    state->block = rblock;
    state->retries = 0;
    state->spacket.event = htons(TFTP_EVENT_ACK);
    state->spacket.u.ack.block = htons(state->block);
    sbytes = sendto(state->sockfd, &state->spacket, 4, MSG_NOSIGNAL,
                    &state->remote_addr, state->remote_addrlen);
    if(sbytes < 0) {
      failf(data, "%s\n", strerror(errno));
    }

    /* Check if completed (That is, a less than full packet is recieved) */
    if (state->rbytes < (int)sizeof(state->spacket)){
      state->state = TFTP_STATE_FIN;
    }
    else {
      state->state = TFTP_STATE_RX;
    }
    break;

  case TFTP_EVENT_TIMEOUT:
    /* Increment the retry count and fail if over the limit */
    state->retries++;
    infof(data,
          "Timeout waiting for block %d ACK.  Retries = %d\n", state->retries);
    if(state->retries > state->retry_max) {
      state->error = TFTP_ERR_TIMEOUT;
      state->state = TFTP_STATE_FIN;
    } else {
      /* Resend the previous ACK */
      sbytes = sendto(state->sockfd, &state->spacket,
                      4, MSG_NOSIGNAL,
                      &state->remote_addr, state->remote_addrlen);
      /* Check all sbytes were sent */
      if(sbytes<0) {
        failf(data, "%s\n", strerror(errno));
      }
    }
    break;

  case TFTP_EVENT_ERROR:
    state->state = TFTP_STATE_FIN;
    break;

  default:
    failf(data, "%s\n", "tftp_rx: internal error");
    break;
  }
  Curl_pgrsSetDownloadCounter(data,
                              (curl_off_t) state->block*512);
}

/**********************************************************
 *
 * tftp_tx
 *
 * Event handler for the TX state
 *
 **********************************************************/
static void tftp_tx(tftp_state_data_t *state, tftp_event_t event)
{
  struct SessionHandle *data = state->conn->data;
  int sbytes;
  int rblock;

  switch(event) {

  case TFTP_EVENT_ACK:
    /* Ack the packet */
    rblock = ntohs(state->rpacket.u.data.block);

    if(rblock != state->block) {
      /* This isn't the expected block.  Log it and up the retry counter */
      infof(data, "Received ACK for block %d, expecting %d\n",
            rblock, state->block);
      state->retries++;
      /* Bail out if over the maximum */
      if(state->retries>state->retry_max) {
        failf(data, "%s\n",
              "tftp_tx: giving up waiting for block %d ack",
              state->block);
      }
      return;
    }
    /* This is the expected packet.  Reset the counters and send the next
       block */
    state->block++;
    state->retries = 0;
    state->spacket.event = htons(TFTP_EVENT_DATA);
    state->spacket.u.ack.block = htons(state->block);
    if(state->block > 1 && state->sbytes < 512) {
      state->state = TFTP_STATE_FIN;
      return;
    }
    Curl_fillreadbuffer(state->conn, 512, &state->sbytes);
    sbytes = sendto(state->sockfd, &state->spacket,
                    4+state->sbytes, MSG_NOSIGNAL,
                    &state->remote_addr, state->remote_addrlen);
    /* Check all sbytes were sent */
    if(sbytes<0) {
      failf(data, "%s\n", strerror(errno));
    }
    break;

  case TFTP_EVENT_TIMEOUT:
    /* Increment the retry counter and log the timeout */
    state->retries++;
    infof(data, "Timeout waiting for block %d ACK. "
          " Retries = %d\n", state->retries);
    /* Decide if we've had enough */
    if(state->retries > state->retry_max) {
      state->error = TFTP_ERR_TIMEOUT;
      state->state = TFTP_STATE_FIN;
    } else {
      /* Re-send the data packet */
      sbytes = sendto(state->sockfd, &state->spacket,
                      4+state->sbytes, MSG_NOSIGNAL,
                      &state->remote_addr, state->remote_addrlen);
      /* Check all sbytes were sent */
      if(sbytes<0) {
        failf(data, "%s\n", strerror(errno));
      }
    }
    break;

  case TFTP_EVENT_ERROR:
    state->state = TFTP_STATE_FIN;
    break;

  default:
    failf(data, "%s\n", "tftp_tx: internal error");
    break;
  }

  /* Update the progress meter */
  Curl_pgrsSetUploadCounter(data, (curl_off_t) state->block*512);
}

/**********************************************************
 *
 * tftp_state_machine
 *
 * The tftp state machine event dispatcher
 *
 **********************************************************/
static CURLcode tftp_state_machine(tftp_state_data_t *state,
                                   tftp_event_t event)
{
  struct SessionHandle *data = state->conn->data;
  switch(state->state) {
  case TFTP_STATE_START:
    DEBUGF(infof(data, "TFTP_STATE_START\n"));
    tftp_send_first(state, event);
    break;
  case TFTP_STATE_RX:
    DEBUGF(infof(data, "TFTP_STATE_RX\n"));
    tftp_rx(state, event);
    break;
  case TFTP_STATE_TX:
    DEBUGF(infof(data, "TFTP_STATE_TX\n"));
    tftp_tx(state, event);
    break;
  case TFTP_STATE_FIN:
    infof(data, "%s\n", "TFTP finished");
    break;
  default:
    DEBUGF(infof(data, "STATE: %d\n", state->state));
    failf(data, "%s\n", "Internal state machine error");
    break;
  }
  return CURLE_OK;
}


/**********************************************************
 *
 * Curl_tftp_connect
 *
 * The connect callback
 *
 **********************************************************/
CURLcode Curl_tftp_connect(struct connectdata *conn, bool *done)
{
  CURLcode code;
  tftp_state_data_t     *state;
  int rc;

  if((state = conn->proto.tftp = calloc(sizeof(tftp_state_data_t), 1))==NULL) {
    return CURLE_OUT_OF_MEMORY;
  }

  state->conn = conn;
  state->sockfd = state->conn->sock[FIRSTSOCKET];
  state->state = TFTP_STATE_START;

#ifdef WIN32
  /* AF_UNSPEC == 0 (from above calloc) doesn't work on Winsock */
  state->local_addr.sa_family = conn->ip_addr->ai_family;
#endif

  tftp_set_timeouts(state);

  /* Bind to any interface, random UDP port */
  rc = bind(state->sockfd, &state->local_addr, sizeof(state->local_addr));
  if(rc) {
    failf(conn->data, "bind() failed; %s\n",
          Curl_strerror(conn,Curl_ourerrno()));
    return CURLE_COULDNT_CONNECT;
  }

  Curl_pgrsStartNow(conn->data);

  *done = TRUE;
  code = CURLE_OK;
  return(code);
}

/**********************************************************
 *
 * Curl_tftp_done
 *
 * The done callback
 *
 **********************************************************/
CURLcode Curl_tftp_done(struct connectdata *conn, CURLcode status)
{
  (void)status; /* unused */

  free(conn->proto.tftp);
  conn->proto.tftp = NULL;
  Curl_pgrsDone(conn);

  return CURLE_OK;
}


/**********************************************************
 *
 * Curl_tftp
 *
 * The do callback
 *
 * This callback handles the entire TFTP transfer
 *
 **********************************************************/

CURLcode Curl_tftp(struct connectdata *conn, bool *done)
{
  struct SessionHandle  *data = conn->data;
  tftp_state_data_t     *state = (tftp_state_data_t *)(conn->proto.tftp);
  tftp_event_t          event;
  CURLcode              code;
  int                   rc;
  struct sockaddr       fromaddr;
  socklen_t             fromlen;
  int                   check_time = 0;

  (void)done; /* prevent compiler warning */

  /* Run the TFTP State Machine */
  for(tftp_state_machine(state, TFTP_EVENT_INIT);
      state->state != TFTP_STATE_FIN;
      tftp_state_machine(state, event) ) {

    /* Wait until ready to read or timeout occurs */
    rc=Curl_select(state->sockfd, CURL_SOCKET_BAD, state->retry_time * 1000);

    if(rc == -1) {
      /* bail out */
      int error = Curl_ourerrno();
      failf(data, "%s\n", Curl_strerror(conn, error));
      event = TFTP_EVENT_ERROR;
    }
    else if (rc==0) {
      /* A timeout occured */
      event = TFTP_EVENT_TIMEOUT;

      /* Force a look at transfer timeouts */
      check_time = 0;

    }
    else {

      /* Receive the packet */
      fromlen=sizeof(fromaddr);
      state->rbytes = recvfrom(state->sockfd,
                               (void *)&state->rpacket, sizeof(state->rpacket),
                               0, &fromaddr, &fromlen);
      if(state->remote_addrlen==0) {
        memcpy(&state->remote_addr, &fromaddr, fromlen);
        state->remote_addrlen = fromlen;
      }

      /* The event is given by the TFTP packet time */
      event = ntohs(state->rpacket.event);

      switch(event) {
      case TFTP_EVENT_DATA:
        Curl_client_write(data, CLIENTWRITE_BODY,
                          (char *)state->rpacket.u.data.data, state->rbytes-4);
        break;
      case TFTP_EVENT_ERROR:
        state->error = ntohs(state->rpacket.u.error.code);
        infof(conn->data, "%s\n", (char *)state->rpacket.u.error.data);
        break;
      case TFTP_EVENT_ACK:
        break;
      case TFTP_EVENT_RRQ:
      case TFTP_EVENT_WRQ:
      default:
        failf(conn->data, "%s\n", "Internal error: Unexpected packet");
        break;
      }

      /* Update the progress meter */
      Curl_pgrsUpdate(conn);

    }

    /* Check for transfer timeout every 10 blocks, or after timeout */
    if(check_time%10==0) {
      time_t current;
      time(&current);
      if(current>state->max_time) {
        DEBUGF(infof(data, "timeout: %d > %d\n",
                     current, state->max_time));
        state->error = TFTP_ERR_TIMEOUT;
        state->state = TFTP_STATE_FIN;
      }
    }

  }

  /* Tell curl we're done */
  Curl_Transfer(conn, -1, -1, FALSE, NULL, -1, NULL);

  /* If we have encountered an error */
  if(state->error) {

    /* Translate internal error codes to curl error codes */
    switch(state->error) {
    case TFTP_ERR_NOTFOUND:
      code = CURLE_TFTP_NOTFOUND;
      break;
    case TFTP_ERR_PERM:
      code = CURLE_TFTP_PERM;
      break;
    case TFTP_ERR_DISKFULL:
      code = CURLE_TFTP_DISKFULL;
      break;
    case TFTP_ERR_ILLEGAL:
      code = CURLE_TFTP_ILLEGAL;
      break;
    case TFTP_ERR_UNKNOWNID:
      code = CURLE_TFTP_UNKNOWNID;
      break;
    case TFTP_ERR_EXISTS:
      code = CURLE_TFTP_EXISTS;
      break;
    case TFTP_ERR_NOSUCHUSER:
      code = CURLE_TFTP_NOSUCHUSER;
      break;
    case TFTP_ERR_TIMEOUT:
      code = CURLE_OPERATION_TIMEOUTED;
      break;
    case TFTP_ERR_NORESPONSE:
      code = CURLE_COULDNT_CONNECT;
      break;
    default:
      code= CURLE_ABORTED_BY_CALLBACK;
      break;
    }
  }
  else
    code = CURLE_OK;
  return code;
}
#endif