aboutsummaryrefslogtreecommitdiff
path: root/tests/ftpserver.pl
blob: e5be66f8afc825932c067038aa6b059ff1981216 (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
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
#!/usr/bin/env perl
#***************************************************************************
#                                  _   _ ____  _
#  Project                     ___| | | |  _ \| |
#                             / __| | | | |_) | |
#                            | (__| |_| |  _ <| |___
#                             \___|\___/|_| \_\_____|
#
# Copyright (C) 1998 - 2007, 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.
#
# $Id$
###########################################################################

# This is the FTP server designed for the curl test suite.
#
# It is meant to exercise curl, it is not meant to be a fully working
# or even very standard compliant server.
#
# You may optionally specify port on the command line, otherwise it'll
# default to port 8921.
#
# All socket/network/TCP related stuff is done by the 'sockfilt' program.
#

use strict;
use IPC::Open2;
#use Time::HiRes qw( gettimeofday ); # not available in perl 5.6

require "getpart.pm";
require "ftp.pm";


my $ftpdnum="";

# open and close each time to allow removal at any time
sub logmsg {
 # if later than perl 5.6 is used
 #   my ($seconds, $microseconds) = gettimeofday;
    my $seconds = time();
    my ($sec,$min,$hour,$mday,$mon,$year,$wday,$yday,$isdst) =
        localtime($seconds);
    open(FTPLOG, ">>log/ftpd$ftpdnum.log");
    printf FTPLOG ("%02d:%02d:%02d ", $hour, $min, $sec);
    print FTPLOG @_;
    close(FTPLOG);
}

sub ftpmsg {
  # append to the server.input file
  open(INPUT, ">>log/server$ftpdnum.input") ||
    logmsg "failed to open log/server$ftpdnum.input\n";

  print INPUT @_;
  close(INPUT);

  # use this, open->print->close system only to make the file
  # open as little as possible, to make the test suite run
  # better on windows/cygwin
}

my $verbose=0; # set to 1 for debugging
my $pasvbadip=0;
my $retrweirdo=0;
my $retrnosize=0;
my $srcdir=".";
my $nosave=0;
my $controldelay=0; # set to 1 to delay the control connect data sending to
 # test that curl deals with that nicely
my $slavepid; # for the DATA connection sockfilt slave process
my $ipv6;
my $ext; # append to log/pid file names
my $grok_eprt;
my $port = 8921; # just a default
my $pidfile = ".ftpd.pid"; # a default, use --pidfile

do {
    if($ARGV[0] eq "-v") {
        $verbose=1;
    }
    elsif($ARGV[0] eq "-s") {
        $srcdir=$ARGV[1];
        shift @ARGV;
    }
    elsif($ARGV[0] eq "--id") {
        $ftpdnum=$ARGV[1];
        shift @ARGV;
    }
    elsif($ARGV[0] eq "--pidfile") {
        $pidfile=$ARGV[1];
        shift @ARGV;
    }
    elsif($ARGV[0] eq "--ipv6") {
        $ipv6="--ipv6";
        $ext="ipv6";
        $grok_eprt = 1;
    }
    elsif($ARGV[0] eq "--port") {
        $port = $ARGV[1];
        shift @ARGV;
    }
} while(shift @ARGV);

sub catch_zap {
    my $signame = shift;
    print STDERR "ftpserver.pl received SIG$signame, exiting\n";
    ftpkillslaves(1);
    die "Somebody sent me a SIG$signame";
}
$SIG{INT} = \&catch_zap;
$SIG{KILL} = \&catch_zap;

my $sfpid;

local(*SFREAD, *SFWRITE);

sub sysread_or_die {
    my $FH     = shift;
    my $scalar = shift;
    my $length = shift;
    my $fcaller;
    my $lcaller;
    my $result;

    $result = sysread($$FH, $$scalar, $length);

    if(not defined $result) {
        ($fcaller, $lcaller) = (caller)[1,2];
        logmsg "Failed to read input\n";
        logmsg "Error: ftp$ftpdnum$ext sysread error: $!\n";
        kill(9, $sfpid);
        waitpid($sfpid, 0);
        die "Died in sysread_or_die() at $fcaller " .
            "line $lcaller. ftp$ftpdnum$ext sysread error: $!\n";
    }
    elsif($result == 0) {
        ($fcaller, $lcaller) = (caller)[1,2];
        logmsg "Failed to read input\n";
        logmsg "Error: ftp$ftpdnum$ext read zero\n";
        kill(9, $sfpid);
        waitpid($sfpid, 0);
        die "Died in sysread_or_die() at $fcaller " .
            "line $lcaller. ftp$ftpdnum$ext read zero\n";
    }

    return $result;
}

sub startsf {
    my $cmd="./server/sockfilt --port $port --logfile log/sockctrl$ftpdnum$ext.log --pidfile .sockfilt$ftpdnum$ext.pid $ipv6";
    $sfpid = open2(*SFREAD, *SFWRITE, $cmd);

    print STDERR "$cmd\n" if($verbose);

    print SFWRITE "PING\n";
    my $pong;
    sysread SFREAD, $pong, 5;

    if($pong !~ /^PONG/) {
        logmsg "Failed sockfilt command: $cmd\n";
        kill(9, $sfpid);
        waitpid($sfpid, 0);
        die "Failed to start sockfilt!";
    }
}

# remove the file here so that if startsf() fails, it is very noticable 
unlink($pidfile);

startsf();

logmsg sprintf("FTP server listens on port IPv%d/$port\n", $ipv6?6:4);
open(PID, ">$pidfile");
print PID $$."\n";
close(PID);

logmsg("logged pid $$ in $pidfile\n");

sub sockfilt {
    my $l;
    foreach $l (@_) {
        printf SFWRITE "DATA\n%04x\n", length($l);
        print SFWRITE $l;
    }
}


# Send data to the client on the control stream, which happens to be plain
# stdout.

sub sendcontrol {
    if(!$controldelay) {
        # spit it all out at once
        sockfilt @_;
    }
    else {
        my $a = join("", @_);
        my @a = split("", $a);

        for(@a) {
            sockfilt $_;
            select(undef, undef, undef, 0.01);
        }
    }
    my $log;
    foreach $log (@_) {
        my $l = $log;
        $l =~ s/[\r\n]//g;
        logmsg "> \"$l\"\n";
    }
}

# Send data to the client on the data stream

sub senddata {
    my $l;
    foreach $l (@_) {
        printf DWRITE "DATA\n%04x\n", length($l);
        print DWRITE $l;
    }
}

# this text is shown before the function specified below is run
my %displaytext = ('USER' => '331 We are happy you popped in!',
                   'PASS' => '230 Welcome you silly person',
                   'PORT' => '200 You said PORT - I say FINE',
                   'TYPE' => '200 I modify TYPE as you wanted',
                   'LIST' => '150 here comes a directory',
                   'NLST' => '150 here comes a directory',
                   'CWD'  => '250 CWD command successful.',
                   'SYST' => '215 UNIX Type: L8', # just fake something
                   'QUIT' => '221 bye bye baby', # just reply something
                   'PWD'  => '257 "/nowhere/anywhere" is current directory',
                   'MKD'  => '257 Created your requested directory',
                   'REST' => '350 Yeah yeah we set it there for you',
                   'DELE' => '200 OK OK OK whatever you say',
                   'RNFR' => '350 Received your order. Please provide more',
                   'RNTO' => '250 Ok, thanks. File renaming completed.',
                   'NOOP' => '200 Yes, I\'m very good at doing nothing.',
                   'PBSZ' => '500 PBSZ not implemented',
                   'PROT' => '500 PROT not implemented',
                   );

# callback functions for certain commands
my %commandfunc = ( 'PORT' => \&PORT_command,
                    'EPRT' => \&PORT_command,
                    'LIST' => \&LIST_command,
                    'NLST' => \&NLST_command,
                    'PASV' => \&PASV_command,
                    'EPSV' => \&PASV_command,
                    'RETR' => \&RETR_command,   
                    'SIZE' => \&SIZE_command,
                    'REST' => \&REST_command,
                    'STOR' => \&STOR_command,
                    'APPE' => \&STOR_command, # append looks like upload
                    'MDTM' => \&MDTM_command,
                    );


sub close_dataconn {
    my ($closed)=@_; # non-zero if already disconnected

    if(!$closed) {
        logmsg "* disconnect data connection\n";
        print DWRITE "DISC\n";
        my $i;
        sysread DREAD, $i, 5;
    }
    else {
        logmsg "data connection already disconnected\n";
    }
    logmsg "=====> Closed data connection\n";

    logmsg "* quit sockfilt for data (pid $slavepid)\n";
    print DWRITE "QUIT\n";
    waitpid $slavepid, 0;
    $slavepid=0;
}

my $rest=0;
sub REST_command {
    $rest = $_[0];
    logmsg "Set REST position to $rest\n"
}

sub LIST_command {
  #  print "150 ASCII data connection for /bin/ls (193.15.23.1,59196) (0 bytes)\r\n";

# this is a built-in fake-dir ;-)
my @ftpdir=("total 20\r\n",
"drwxr-xr-x   8 98       98           512 Oct 22 13:06 .\r\n",
"drwxr-xr-x   8 98       98           512 Oct 22 13:06 ..\r\n",
"drwxr-xr-x   2 98       98           512 May  2  1996 .NeXT\r\n",
"-r--r--r--   1 0        1             35 Jul 16  1996 README\r\n",
"lrwxrwxrwx   1 0        1              7 Dec  9  1999 bin -> usr/bin\r\n",
"dr-xr-xr-x   2 0        1            512 Oct  1  1997 dev\r\n",
"drwxrwxrwx   2 98       98           512 May 29 16:04 download.html\r\n",
"dr-xr-xr-x   2 0        1            512 Nov 30  1995 etc\r\n",
"drwxrwxrwx   2 98       1            512 Oct 30 14:33 pub\r\n",
"dr-xr-xr-x   5 0        1            512 Oct  1  1997 usr\r\n");

    logmsg "pass LIST data on data connection\n";
    for(@ftpdir) {
        senddata $_;
    }
    close_dataconn(0);
    sendcontrol "226 ASCII transfer complete\r\n";
    return 0;
}

sub NLST_command {
    my @ftpdir=("file", "with space", "fake", "..", " ..", "funny", "README");
    logmsg "pass NLST data on data connection\n";
    for(@ftpdir) {
        senddata "$_\r\n";
    }
    close_dataconn(0);
    sendcontrol "226 ASCII transfer complete\r\n";
    return 0;
}

sub MDTM_command {
    my $testno = $_[0];

    loadtest("$srcdir/data/test$testno");

    my @data = getpart("reply", "mdtm");

    my $reply = $data[0];
    chomp $reply;

    if($reply <0) {
        sendcontrol "550 $testno: no such file.\r\n";
    }
    elsif($reply) {
        sendcontrol "$reply\r\n";
    }
    else {
        sendcontrol "500 MDTM: no such command.\r\n";
    }
    return 0;
}

sub SIZE_command {
    my $testno = $_[0];

    loadtest("$srcdir/data/test$testno");

    if($testno eq "verifiedserver") {
        my $response = "WE ROOLZ: $$\r\n";
        my $size = length($response);
        sendcontrol "213 $size\r\n";
        return 0;
    }

    my @data = getpart("reply", "size");

    my $size = $data[0];

    if($size) {
        if($size > -1) {
            sendcontrol "213 $size\r\n";
        }
        else {
            sendcontrol "550 $testno: No such file or directory.\r\n";
        }
    }
    else {
        $size=0;
        @data = getpart("reply", "data");
        for(@data) {
            $size += length($_);
        }
        if($size) {
            sendcontrol "213 $size\r\n";
        }
        else {
            sendcontrol "550 $testno: No such file or directory.\r\n";
        }
    }
    return 0;
}

sub RETR_command {
    my ($testno) = @_;

    if($testno =~ /^verifiedserver$/) {
        # this is the secret command that verifies that this actually is
        # the curl test server
        my $response = "WE ROOLZ: $$\r\n";
        my $len = length($response);
        sendcontrol "150 Binary junk ($len bytes).\r\n";
        senddata "WE ROOLZ: $$\r\n";
        close_dataconn(0);
        sendcontrol "226 File transfer complete\r\n";
        if($verbose) {
            print STDERR "FTPD: We returned proof we are the test server\n";
        }
        return 0;
    }

    $testno =~ s/^([^0-9]*)//;

    loadtest("$srcdir/data/test$testno");

    my @data = getpart("reply", "data");

    my $size=0;
    for(@data) {
        $size += length($_);
    }

    my %hash = getpartattr("reply", "data");

    if($size || $hash{'sendzero'}) {
    
        if($rest) {
            # move read pointer forward
            $size -= $rest;
            logmsg "REST $rest was removed from size, makes $size left\n";
            $rest = 0; # reset REST offset again
        }
        if($retrweirdo) {
            sendcontrol "150 Binary data connection for $testno () ($size bytes).\r\n",
            "226 File transfer complete\r\n";

            for(@data) {
                my $send = $_;
                senddata $send;
            }
            close_dataconn(0);
            $retrweirdo=0; # switch off the weirdo again!
        }
        else {
            my $sz = "($size bytes)";
            if($retrnosize) {
                $sz = "size?";
            }

            sendcontrol "150 Binary data connection for $testno () $sz.\r\n";

            for(@data) {
                my $send = $_;
                senddata $send;
            }
            close_dataconn(0);
            sendcontrol "226 File transfer complete\r\n";
        }
    }
    else {
        sendcontrol "550 $testno: No such file or directory.\r\n";
    }
    return 0;
}

sub STOR_command {
    my $testno=$_[0];

    my $filename = "log/upload.$testno";

    logmsg "STOR test number $testno in $filename\n";

    sendcontrol "125 Gimme gimme gimme!\r\n";

    open(FILE, ">$filename") ||
        return 0; # failed to open output

    my $line;
    my $ulsize=0;
    my $disc=0;
    while (5 == (sysread DREAD, $line, 5)) {
        if($line eq "DATA\n") {
            my $i;
            sysread DREAD, $i, 5;

            #print STDERR "  GOT: $i";

            my $size = hex($i);
            sysread DREAD, $line, $size;
            
            #print STDERR "  GOT: $size bytes\n";

            $ulsize += $size;
            print FILE $line if(!$nosave);
            logmsg "> Appending $size bytes to file\n";
        }
        elsif($line eq "DISC\n") {
            # disconnect!
            $disc=1;
            last;
        }
        else {
            logmsg "No support for: $line";
            last;
        }
    }
    if($nosave) {
        print FILE "$ulsize bytes would've been stored here\n";
    }
    close(FILE);
    close_dataconn($disc);
    logmsg "received $ulsize bytes upload\n";
    sendcontrol "226 File transfer complete\r\n";
    return 0;
}

sub PASV_command {
    my ($arg, $cmd)=@_;
    my $pasvport;
    my $pidf=".sockdata$ftpdnum$ext.pid";

    my $prev = checkserver($pidf);
    if($prev > 0) {
        print "kill existing server: $prev\n" if($verbose);
        kill(9, $prev);
    }

    # We fire up a new sockfilt to do the data tranfer for us.
    $slavepid = open2(\*DREAD, \*DWRITE,
                      "./server/sockfilt --port 0 --logfile log/sockdata$ftpdnum$ext.log --pidfile $pidf $ipv6");

    print DWRITE "PING\n";
    my $pong;

    sysread_or_die(\*DREAD, \$pong, 5);

    if($pong !~ /^PONG/) {
        kill(9, $slavepid);
        waitpid($slavepid, 0);
        sendcontrol "500 no free ports!\r\n";
        logmsg "failed to run sockfilt for data connection\n";
        return 0;
    }

    logmsg "Run sockfilt for data on pid $slavepid\n";

    # Find out what port we listen on
    my $i;
    print DWRITE "PORT\n";
        
    # READ the response code
    sysread_or_die(\*DREAD, \$i, 5);

    # READ the response size
    sysread_or_die(\*DREAD, \$i, 5);

    my $size = hex($i);
        
    # READ the response data
    sysread_or_die(\*DREAD, \$i, $size);
        
    # The data is in the format
    # IPvX/NNN

    if($i =~ /IPv(\d)\/(\d+)/) {
        # FIX: deal with IP protocol version
        $pasvport = $2;
    }

    if($cmd ne "EPSV") {
        # PASV reply
        my $p="127,0,0,1";
        if($pasvbadip) {
            $p="1,2,3,4";
        }
        sendcontrol sprintf("227 Entering Passive Mode ($p,%d,%d)\n",
                            ($pasvport/256), ($pasvport%256));
    }
    else {
        # EPSV reply
        sendcontrol sprintf("229 Entering Passive Mode (|||%d|)\n", $pasvport);
    }

    eval {
        local $SIG{ALRM} = sub { die "alarm\n" };

	# assume swift operations unless explicitly slow
	alarm ($controldelay?20:5);

        # Wait for 'CNCT'
	my $input;

        while(sysread(DREAD, $input, 5)) {

	    if($input !~ /^CNCT/) {
		# we wait for a connected client
		logmsg "Odd, we got $input from client\n";
		next;
	    }
	    logmsg "====> Client DATA connect\n";
	    last;
	}
        alarm 0;
    };
    if ($@) {
        # timed out

        print DWRITE "QUIT\n";
        waitpid $slavepid, 0;
        logmsg "accept failed\n";
        $slavepid=0;
        return;
    }
    else {
        logmsg "data connection setup on port $pasvport\n";
    }

    return;
}

# Support both PORT and EPRT here. Consider LPRT too.

sub PORT_command {
    my ($arg, $cmd) = @_;
    my $port;

    # We always ignore the given IP and use localhost.

    if($cmd eq "PORT") {
        if($arg !~ /(\d+),(\d+),(\d+),(\d+),(\d+),(\d+)/) {
            logmsg "bad PORT-line: $arg\n";
            sendcontrol "500 silly you, go away\r\n";
            return 0;
        }
        $port = ($5<<8)+$6;
    }
    # EPRT |2|::1|49706|
    elsif(($cmd eq "EPRT") && ($grok_eprt)) {
        if($arg !~ /(\d+)\|([^\|]+)\|(\d+)/) {
            sendcontrol "500 silly you, go away\r\n";
            return 0;
        }
        sendcontrol "200 Thanks for dropping by. We contact you later\r\n";
        $port = $3;
    }
    else {
        sendcontrol "500 we don't like $cmd now\r\n";
        return 0;
    }

    if(!$port || $port > 65535) {
        print STDERR "very illegal PORT number: $port\n";
        return 1;
    }

    # We fire up a new sockfilt to do the data tranfer for us.
    # FIX: make it use IPv6 if need be
    $slavepid = open2(\*DREAD, \*DWRITE,
                      "./server/sockfilt --connect $port --logfile log/sockdata$ftpdnum$ext.log --pidfile .sockdata$ftpdnum$ext.pid $ipv6");

    print DWRITE "PING\n";
    my $pong;
    sysread DREAD, $pong, 5;

    if($pong !~ /^PONG/) {
        logmsg "Failed sockfilt for data connection\n";
        kill(9, $slavepid);
        waitpid($slavepid, 0);
    }

    logmsg "====> Client DATA connect to port $port\n";

    return;
}

my %customreply;
my %customcount;
my %delayreply;
sub customize {
    undef %customreply;

    $nosave = 0; # default is to save as normal
    $controldelay = 0; # default is no delaying the responses
    $retrweirdo = 0;
    $retrnosize = 0;
    $pasvbadip = 0;
    $nosave = 0;
    %customcount = ();
    %delayreply = ();

    open(CUSTOM, "<log/ftpserver.cmd") ||
        return 1;

    logmsg "FTPD: Getting commands from log/ftpserver.cmd\n";

    while(<CUSTOM>) {
        if($_ =~ /REPLY ([A-Z]+) (.*)/) {
            $customreply{$1}=$2;
            logmsg "FTPD: set custom reply for $1\n";
        }
        if($_ =~ /COUNT ([A-Z]+) (.*)/) {
            # we blank the customreply for this command when having
            # been used this number of times
            $customcount{$1}=$2;
            logmsg "FTPD: blank custom reply for $1 after $2 uses\n";
        }
        elsif($_ =~ /DELAY ([A-Z]+) (\d*)/) {
            $delayreply{$1}=$2;
            logmsg "FTPD: delay reply for $1 with $2 seconds\n";
        }
        elsif($_ =~ /SLOWDOWN/) {
            $controldelay=1;
            logmsg "FTPD: send response with 0.1 sec delay between each byte\n";
        }
        elsif($_ =~ /RETRWEIRDO/) {
            logmsg "FTPD: instructed to use RETRWEIRDO\n";
            $retrweirdo=1;
        }
        elsif($_ =~ /RETRNOSIZE/) {
            logmsg "FTPD: instructed to use RETRNOSIZE\n";
            $retrnosize=1;
        }
        elsif($_ =~ /PASVBADIP/) {
            logmsg "FTPD: instructed to use PASVBADIP\n";
            $pasvbadip=1;
        }
        elsif($_ =~ /NOSAVE/) {
            # don't actually store the file we upload - to be used when
            # uploading insanely huge amounts
            $nosave = 1;
            logmsg "FTPD: NOSAVE prevents saving of uploaded data\n";
        }
    }
    close(CUSTOM);
}

my @welcome=(
            '220-        _   _ ____  _     '."\r\n",
            '220-    ___| | | |  _ \| |    '."\r\n",
            '220-   / __| | | | |_) | |    '."\r\n",
            '220-  | (__| |_| |  _ <| |___ '."\r\n",
            '220    \___|\___/|_| \_\_____|'."\r\n");


while(1) {
    #
    # We read 'sockfilt' commands.
    # 
    my $input;

    logmsg "Awaiting input\n";
    sysread_or_die(\*SFREAD, \$input, 5);

    if($input !~ /^CNCT/) {
        # we wait for a connected client
        logmsg "sockfilt said: $input";
        next;
    }
    logmsg "====> Client connect\n";

    # flush data:
    $| = 1;

    kill(9, $slavepid) if($slavepid);
    waitpid($slavepid, 0) if($slavepid);
    $slavepid=0;
        
    &customize(); # read test control instructions

    sendcontrol @welcome;
    if($verbose) {
        for(@welcome) {
            print STDERR "OUT: $_";
        }
    }

    while(1) {
        my $i;

        # Now we expect to read DATA\n[hex size]\n[prot], where the [prot]
        # part only is FTP lingo.

        # COMMAND
        sysread_or_die(\*SFREAD, \$i, 5);

        if($i !~ /^DATA/) {
            logmsg "sockfilt said $i";
            if($i =~ /^DISC/) {
                # disconnect
                last;
            }
            next;
        }

        # SIZE of data
        sysread_or_die(\*SFREAD, \$i, 5);

        my $size = hex($i);

        # data
        sysread SFREAD, $_, $size;
        
        ftpmsg $_;
        
        # Remove trailing CRLF.
        s/[\n\r]+$//;

        unless (m/^([A-Z]{3,4})\s?(.*)/i) {
            sendcontrol "500 '$_': command not understood.\r\n";
            last;
        }
        my $FTPCMD=$1;
        my $FTPARG=$2;
        my $full=$_;
                 
        logmsg "< \"$full\"\n";

        if($verbose) {
            print STDERR "IN: $full\n";
        }

        my $delay = $delayreply{$FTPCMD};
        if($delay) {
            # just go sleep this many seconds!
            logmsg("Sleep for $delay seconds\n");
            sleep($delay);
        }

        my $text;
        $text = $customreply{$FTPCMD};
        my $fake = $text;
        if($text eq "") {
            $text = $displaytext{$FTPCMD};
        }
        else {
            if($customcount{$FTPCMD} && (!--$customcount{$FTPCMD})) {
                # used enough number of times, now blank the customreply
                $customreply{$FTPCMD}="";
            }
        }
        my $check;
        if($text) {
            sendcontrol "$text\r\n";
        }
        else {
            $check=1; # no repsonse yet
        }

        if($fake eq "") {
            # only perform this if we're not faking a reply
            my $func = $commandfunc{$FTPCMD};
            if($func) {
                &$func($FTPARG, $FTPCMD);
                $check=0; # taken care of
            }
        }

        if($check) {
            logmsg "$FTPCMD wasn't handled!\n";
            sendcontrol "500 $FTPCMD is not dealt with!\r\n";
        }
            
    } # while(1)
    logmsg "====> Client disconnected\n";
}

print SFWRITE "QUIT\n";
waitpid $sfpid, 0;
exit;