aboutsummaryrefslogtreecommitdiffstats
path: root/contrib/lukemftpd/src/ftpcmd.y
blob: 804a26b2b49a95df8de623abc3dff48cb16fe8e4 (plain) (blame)
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
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
/*	$NetBSD: ftpcmd.y,v 1.84 2006/02/01 14:20:12 christos Exp $	*/

/*-
 * Copyright (c) 1997-2005 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Luke Mewburn.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *        This product includes software developed by the NetBSD
 *        Foundation, Inc. and its contributors.
 * 4. Neither the name of The NetBSD Foundation nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * Copyright (c) 1985, 1988, 1993, 1994
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	@(#)ftpcmd.y	8.3 (Berkeley) 4/6/94
 */

/*
 * Grammar for FTP commands.
 * See RFC 959.
 */

%{
#include <sys/cdefs.h>

#ifndef lint
#if 0
static char sccsid[] = "@(#)ftpcmd.y	8.3 (Berkeley) 4/6/94";
#else
__RCSID("$NetBSD: ftpcmd.y,v 1.84 2006/02/01 14:20:12 christos Exp $");
#endif
#endif /* not lint */

#include <sys/param.h>
#include <sys/socket.h>
#include <sys/stat.h>

#include <netinet/in.h>
#include <arpa/ftp.h>
#include <arpa/inet.h>

#include <ctype.h>
#include <errno.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <time.h>
#include <tzfile.h>
#include <unistd.h>
#include <netdb.h>

#ifdef KERBEROS5
#include <krb5/krb5.h>
#endif

#include "extern.h"
#include "version.h"

static	int cmd_type;
static	int cmd_form;
static	int cmd_bytesz;

char	cbuf[FTP_BUFLEN];
char	*cmdp;
char	*fromname;

extern int	epsvall;
struct tab	sitetab[];

static	int	check_write(const char *, int);
static	void	help(struct tab *, const char *);
static	void	port_check(const char *, int);
	int	yylex(void);

%}

%union {
	struct {
		LLT	ll;
		int	i;
	} u;
	char   *s;
}

%token
	A	B	C	E	F	I
	L	N	P	R	S	T

	SP	CRLF	COMMA	ALL

	USER	PASS	ACCT	CWD	CDUP	SMNT
	QUIT	REIN	PORT	PASV	TYPE	STRU
	MODE	RETR	STOR	STOU	APPE	ALLO
	REST	RNFR	RNTO	ABOR	DELE	RMD
	MKD	PWD	LIST	NLST	SITE	SYST
	STAT	HELP	NOOP

	AUTH	ADAT	PROT	PBSZ	CCC	MIC
	CONF	ENC

	FEAT	OPTS

	SIZE	MDTM	MLST	MLSD

	LPRT	LPSV	EPRT	EPSV

	MAIL	MLFL	MRCP	MRSQ	MSAM	MSND
	MSOM

	CHMOD	IDLE	RATEGET	RATEPUT	UMASK

	LEXERR

%token	<s> STRING
%token	<u> NUMBER

%type	<u.i> check_login octal_number byte_size
%type	<u.i> struct_code mode_code type_code form_code decimal_integer
%type	<s> pathstring pathname password username
%type	<s> mechanism_name base64data prot_code

%start	cmd_sel

%%

cmd_sel
	: cmd
		{
			REASSIGN(fromname, NULL);
			restart_point = (off_t) 0;
		}

	| rcmd

	;

cmd
						/* RFC 959 */
	: USER SP username CRLF
		{
			user($3);
			free($3);
		}

	| PASS SP password CRLF
		{
			pass($3);
			memset($3, 0, strlen($3));
			free($3);
		}

	| CWD check_login CRLF
		{
			if ($2)
				cwd(homedir);
		}

	| CWD check_login SP pathname CRLF
		{
			if ($2 && $4 != NULL)
				cwd($4);
			if ($4 != NULL)
				free($4);
		}

	| CDUP check_login CRLF
		{
			if ($2)
				cwd("..");
		}

	| QUIT CRLF
		{
			if (logged_in) {
				reply(-221, "%s", "");
				reply(0,
 "Data traffic for this session was " LLF " byte%s in " LLF " file%s.",
				    (LLT)total_data, PLURAL(total_data),
				    (LLT)total_files, PLURAL(total_files));
				reply(0,
 "Total traffic for this session was " LLF " byte%s in " LLF " transfer%s.",
				    (LLT)total_bytes, PLURAL(total_bytes),
				    (LLT)total_xfers, PLURAL(total_xfers));
			}
			reply(221,
			    "Thank you for using the FTP service on %s.",
			    hostname);
			if (logged_in && logging) {
				syslog(LOG_INFO,
		"Data traffic: " LLF " byte%s in " LLF " file%s",
				    (LLT)total_data, PLURAL(total_data),
				    (LLT)total_files, PLURAL(total_files));
				syslog(LOG_INFO,
		"Total traffic: " LLF " byte%s in " LLF " transfer%s",
				    (LLT)total_bytes, PLURAL(total_bytes),
				    (LLT)total_xfers, PLURAL(total_xfers));
			}

			dologout(0);
		}

	| PORT check_login SP host_port CRLF
		{
			if ($2)
				port_check("PORT", AF_INET);
		}

	| LPRT check_login SP host_long_port4 CRLF
		{
			if ($2)
				port_check("LPRT", AF_INET);
		}

	| LPRT check_login SP host_long_port6 CRLF
		{
#ifdef INET6
			if ($2)
				port_check("LPRT", AF_INET6);
#else
			reply(500, "IPv6 support not available.");
#endif
		}

	| EPRT check_login SP STRING CRLF
		{
			if ($2) {
				if (extended_port($4) == 0)
					port_check("EPRT", -1);
			}
			free($4);
		}

	| PASV check_login CRLF
		{
			if ($2) {
				if (CURCLASS_FLAGS_ISSET(passive))
					passive();
				else
					reply(500, "PASV mode not available.");
			}
		}

	| LPSV check_login CRLF
		{
			if ($2) {
				if (CURCLASS_FLAGS_ISSET(passive)) {
					if (epsvall)
						reply(501,
						    "LPSV disallowed after EPSV ALL");
					else
						long_passive("LPSV", PF_UNSPEC);
				} else
					reply(500, "LPSV mode not available.");
			}
		}

	| EPSV check_login SP NUMBER CRLF
		{
			if ($2) {
				if (CURCLASS_FLAGS_ISSET(passive))
					long_passive("EPSV",
					    epsvproto2af($4.i));
				else
					reply(500, "EPSV mode not available.");
			}
		}

	| EPSV check_login SP ALL CRLF
		{
			if ($2) {
				if (CURCLASS_FLAGS_ISSET(passive)) {
					reply(200,
					    "EPSV ALL command successful.");
					epsvall++;
				} else
					reply(500, "EPSV mode not available.");
			}
		}

	| EPSV check_login CRLF
		{
			if ($2) {
				if (CURCLASS_FLAGS_ISSET(passive))
					long_passive("EPSV", PF_UNSPEC);
				else
					reply(500, "EPSV mode not available.");
			}
		}

	| TYPE check_login SP type_code CRLF
		{
			if ($2) {

			switch (cmd_type) {

			case TYPE_A:
				if (cmd_form == FORM_N) {
					reply(200, "Type set to A.");
					type = cmd_type;
					form = cmd_form;
				} else
					reply(504, "Form must be N.");
				break;

			case TYPE_E:
				reply(504, "Type E not implemented.");
				break;

			case TYPE_I:
				reply(200, "Type set to I.");
				type = cmd_type;
				break;

			case TYPE_L:
#if NBBY == 8
				if (cmd_bytesz == 8) {
					reply(200,
					    "Type set to L (byte size 8).");
					type = cmd_type;
				} else
					reply(504, "Byte size must be 8.");
#else /* NBBY == 8 */
				UNIMPLEMENTED for NBBY != 8
#endif /* NBBY == 8 */
			}
			
			}
		}

	| STRU check_login SP struct_code CRLF
		{
			if ($2) {
				switch ($4) {

				case STRU_F:
					reply(200, "STRU F ok.");
					break;

				default:
					reply(504, "Unimplemented STRU type.");
				}
			}
		}

	| MODE check_login SP mode_code CRLF
		{
			if ($2) {
				switch ($4) {

				case MODE_S:
					reply(200, "MODE S ok.");
					break;

				default:
					reply(502, "Unimplemented MODE type.");
				}
			}
		}

	| RETR check_login SP pathname CRLF
		{
			if ($2 && $4 != NULL)
				retrieve(NULL, $4);
			if ($4 != NULL)
				free($4);
		}

	| STOR SP pathname CRLF
		{
			if (check_write($3, 1))
				store($3, "w", 0);
			if ($3 != NULL)
				free($3);
		}

	| STOU SP pathname CRLF
		{
			if (check_write($3, 1))
				store($3, "w", 1);
			if ($3 != NULL)
				free($3);
		}
		
	| APPE SP pathname CRLF
		{
			if (check_write($3, 1))
				store($3, "a", 0);
			if ($3 != NULL)
				free($3);
		}

	| ALLO check_login SP NUMBER CRLF
		{
			if ($2)
				reply(202, "ALLO command ignored.");
		}

	| ALLO check_login SP NUMBER SP R SP NUMBER CRLF
		{
			if ($2)
				reply(202, "ALLO command ignored.");
		}

	| RNTO SP pathname CRLF
		{
			if (check_write($3, 0)) {
				if (fromname) {
					renamecmd(fromname, $3);
					REASSIGN(fromname, NULL);
				} else {
					reply(503, "Bad sequence of commands.");
				}
			}
			if ($3 != NULL)
				free($3);
		}

	| ABOR check_login CRLF
		{
			if (is_oob)
				abor();
			else if ($2)
				reply(225, "ABOR command successful.");
		}

	| DELE SP pathname CRLF
		{
			if (check_write($3, 0))
				delete($3);
			if ($3 != NULL)
				free($3);
		}

	| RMD SP pathname CRLF
		{
			if (check_write($3, 0))
				removedir($3);
			if ($3 != NULL)
				free($3);
		}

	| MKD SP pathname CRLF
		{
			if (check_write($3, 0))
				makedir($3);
			if ($3 != NULL)
				free($3);
		}

	| PWD check_login CRLF
		{
			if ($2)
				pwd();
		}

	| LIST check_login CRLF
		{
			char *argv[] = { INTERNAL_LS, "-lgA", NULL };
			
			if (CURCLASS_FLAGS_ISSET(hidesymlinks))
				argv[1] = "-LlgA";
			if ($2)
				retrieve(argv, "");
		}

	| LIST check_login SP pathname CRLF
		{
			char *argv[] = { INTERNAL_LS, "-lgA", NULL, NULL };

			if (CURCLASS_FLAGS_ISSET(hidesymlinks))
				argv[1] = "-LlgA";
			if ($2 && $4 != NULL) {
				argv[2] = $4;
				retrieve(argv, $4);
			}
			if ($4 != NULL)
				free($4);
		}

	| NLST check_login CRLF
		{
			if ($2)
				send_file_list(".");
		}

	| NLST check_login SP pathname CRLF
		{
			if ($2)
				send_file_list($4);
			free($4);
		}

	| SITE SP HELP CRLF
		{
			help(sitetab, NULL);
		}

	| SITE SP CHMOD SP octal_number SP pathname CRLF
		{
			if (check_write($7, 0)) {
				if (($5 == -1) || ($5 > 0777))
					reply(501,
				"CHMOD: Mode value must be between 0 and 0777");
				else if (chmod($7, $5) < 0)
					perror_reply(550, $7);
				else
					reply(200, "CHMOD command successful.");
			}
			if ($7 != NULL)
				free($7);
		}

	| SITE SP HELP SP STRING CRLF
		{
			help(sitetab, $5);
			free($5);
		}

	| SITE SP IDLE check_login CRLF
		{
			if ($4) {
				reply(200,
				    "Current IDLE time limit is " LLF
				    " seconds; max " LLF,
				    (LLT)curclass.timeout,
				    (LLT)curclass.maxtimeout);
			}
		}

	| SITE SP IDLE check_login SP NUMBER CRLF
		{
			if ($4) {
				if ($6.i < 30 || $6.i > curclass.maxtimeout) {
					reply(501,
				"IDLE time limit must be between 30 and "
					    LLF " seconds",
					    (LLT)curclass.maxtimeout);
				} else {
					curclass.timeout = $6.i;
					(void) alarm(curclass.timeout);
					reply(200,
					    "IDLE time limit set to "
					    LLF " seconds",
					    (LLT)curclass.timeout);
				}
			}
		}

	| SITE SP RATEGET check_login CRLF
		{
			if ($4) {
				reply(200,
				    "Current RATEGET is " LLF " bytes/sec",
				    (LLT)curclass.rateget);
			}
		}

	| SITE SP RATEGET check_login SP STRING CRLF
		{
			char errbuf[100];
			char *p = $6;
			LLT rate;

			if ($4) {
				rate = strsuftollx("RATEGET", p, 0,
				    curclass.maxrateget
				    ? curclass.maxrateget
				    : LLTMAX, errbuf, sizeof(errbuf));
				if (errbuf[0])
					reply(501, "%s", errbuf);
				else {
					curclass.rateget = rate;
					reply(200,
					    "RATEGET set to " LLF " bytes/sec",
					    (LLT)curclass.rateget);
				}
			}
			free($6);
		}

	| SITE SP RATEPUT check_login CRLF
		{
			if ($4) {
				reply(200,
				    "Current RATEPUT is " LLF " bytes/sec",
				    (LLT)curclass.rateput);
			}
		}

	| SITE SP RATEPUT check_login SP STRING CRLF
		{
			char errbuf[100];
			char *p = $6;
			LLT rate;

			if ($4) {
				rate = strsuftollx("RATEPUT", p, 0,
				    curclass.maxrateput
				    ? curclass.maxrateput
				    : LLTMAX, errbuf, sizeof(errbuf));
				if (errbuf[0])
					reply(501, "%s", errbuf);
				else {
					curclass.rateput = rate;
					reply(200,
					    "RATEPUT set to " LLF " bytes/sec",
					    (LLT)curclass.rateput);
				}
			}
			free($6);
		}

	| SITE SP UMASK check_login CRLF
		{
			int oldmask;

			if ($4) {
				oldmask = umask(0);
				(void) umask(oldmask);
				reply(200, "Current UMASK is %03o", oldmask);
			}
		}

	| SITE SP UMASK check_login SP octal_number CRLF
		{
			int oldmask;

			if ($4 && check_write("", 0)) {
				if (($6 == -1) || ($6 > 0777)) {
					reply(501, "Bad UMASK value");
				} else {
					oldmask = umask($6);
					reply(200,
					    "UMASK set to %03o (was %03o)",
					    $6, oldmask);
				}
			}
		}

	| SYST CRLF
		{
			if (EMPTYSTR(version))
				reply(215, "UNIX Type: L%d", NBBY);
			else
				reply(215, "UNIX Type: L%d Version: %s", NBBY,
				    version);
		}

	| STAT check_login SP pathname CRLF
		{
			if ($2 && $4 != NULL)
				statfilecmd($4);
			if ($4 != NULL)
				free($4);
		}
		
	| STAT CRLF
		{
			if (is_oob)
				statxfer();
			else
				statcmd();
		}

	| HELP CRLF
		{
			help(cmdtab, NULL);
		}

	| HELP SP STRING CRLF
		{
			char *cp = $3;

			if (strncasecmp(cp, "SITE", 4) == 0) {
				cp = $3 + 4;
				if (*cp == ' ')
					cp++;
				if (*cp)
					help(sitetab, cp);
				else
					help(sitetab, NULL);
			} else
				help(cmdtab, $3);
			free($3);
		}

	| NOOP CRLF
		{
			reply(200, "NOOP command successful.");
		}

						/* RFC 2228 */
	| AUTH SP mechanism_name CRLF
		{
			reply(502, "RFC 2228 authentication not implemented.");
			free($3);
		}

	| ADAT SP base64data CRLF
		{
			reply(503,
			    "Please set authentication state with AUTH.");
			free($3);
		}

	| PROT SP prot_code CRLF
		{
			reply(503,
			    "Please set protection buffer size with PBSZ.");
			free($3);
		}

	| PBSZ SP decimal_integer CRLF
		{
			reply(503,
			    "Please set authentication state with AUTH.");
		}

	| CCC CRLF
		{
			reply(533, "No protection enabled.");
		}

	| MIC SP base64data CRLF
		{
			reply(502, "RFC 2228 authentication not implemented.");
			free($3);
		}

	| CONF SP base64data CRLF
		{
			reply(502, "RFC 2228 authentication not implemented.");
			free($3);
		}

	| ENC SP base64data CRLF
		{
			reply(502, "RFC 2228 authentication not implemented.");
			free($3);
		}

						/* RFC 2389 */
	| FEAT CRLF
		{

			feat();
		}

	| OPTS SP STRING CRLF
		{
			
			opts($3);
			free($3);
		}


				/* extensions from draft-ietf-ftpext-mlst-11 */

		/*
		 * Return size of file in a format suitable for
		 * using with RESTART (we just count bytes).
		 */
	| SIZE check_login SP pathname CRLF
		{
			if ($2 && $4 != NULL)
				sizecmd($4);
			if ($4 != NULL)
				free($4);
		}

		/*
		 * Return modification time of file as an ISO 3307
		 * style time. E.g. YYYYMMDDHHMMSS or YYYYMMDDHHMMSS.xxx
		 * where xxx is the fractional second (of any precision,
		 * not necessarily 3 digits)
		 */
	| MDTM check_login SP pathname CRLF
		{
			if ($2 && $4 != NULL) {
				struct stat stbuf;
				if (stat($4, &stbuf) < 0)
					perror_reply(550, $4);
				else if (!S_ISREG(stbuf.st_mode)) {
					reply(550, "%s: not a plain file.", $4);
				} else {
					struct tm *t;

					t = gmtime(&stbuf.st_mtime);
					reply(213,
					    "%04d%02d%02d%02d%02d%02d",
					    TM_YEAR_BASE + t->tm_year,
					    t->tm_mon+1, t->tm_mday,
					    t->tm_hour, t->tm_min, t->tm_sec);
				}
			}
			if ($4 != NULL)
				free($4);
		}

	| MLST check_login SP pathname CRLF
		{
			if ($2 && $4 != NULL)
				mlst($4);
			if ($4 != NULL)
				free($4);
		}
		
	| MLST check_login CRLF
		{
			mlst(NULL);
		}

	| MLSD check_login SP pathname CRLF
		{
			if ($2 && $4 != NULL)
				mlsd($4);
			if ($4 != NULL)
				free($4);
		}
		
	| MLSD check_login CRLF
		{
			mlsd(NULL);
		}

	| error CRLF
		{
			yyerrok;
		}
	;

rcmd
	: REST check_login SP NUMBER CRLF
		{
			if ($2) {
				REASSIGN(fromname, NULL);
				restart_point = (off_t)$4.ll;
				reply(350,
    "Restarting at " LLF ". Send STORE or RETRIEVE to initiate transfer.",
				    (LLT)restart_point);
			}
		}

	| RNFR SP pathname CRLF
		{
			restart_point = (off_t) 0;
			if (check_write($3, 0)) {
				REASSIGN(fromname, NULL);
				fromname = renamefrom($3);
			}
			if ($3 != NULL)
				free($3);
		}
	;

username
	: STRING
	;

password
	: /* empty */
		{
			$$ = (char *)calloc(1, sizeof(char));
		}

	| STRING
	;

byte_size
	: NUMBER
		{
			$$ = $1.i;
		}
	;

host_port
	: NUMBER COMMA NUMBER COMMA NUMBER COMMA NUMBER COMMA
		NUMBER COMMA NUMBER
		{
			char *a, *p;

			memset(&data_dest, 0, sizeof(data_dest));
			data_dest.su_len = sizeof(struct sockaddr_in);
			data_dest.su_family = AF_INET;
			p = (char *)&data_dest.su_port;
			p[0] = $9.i; p[1] = $11.i;
			a = (char *)&data_dest.su_addr;
			a[0] = $1.i; a[1] = $3.i; a[2] = $5.i; a[3] = $7.i;
		}
	;

host_long_port4
	: NUMBER COMMA NUMBER COMMA NUMBER COMMA NUMBER COMMA
		NUMBER COMMA NUMBER COMMA NUMBER COMMA NUMBER COMMA
		NUMBER
		{
			char *a, *p;

			memset(&data_dest, 0, sizeof(data_dest));
			data_dest.su_len = sizeof(struct sockaddr_in);
			data_dest.su_family = AF_INET;
			p = (char *)&data_dest.su_port;
			p[0] = $15.i; p[1] = $17.i;
			a = (char *)&data_dest.su_addr;
			a[0] = $5.i; a[1] = $7.i; a[2] = $9.i; a[3] = $11.i;

			/* reject invalid LPRT command */
			if ($1.i != 4 || $3.i != 4 || $13.i != 2)
				memset(&data_dest, 0, sizeof(data_dest));
		}
	;

host_long_port6
	: NUMBER COMMA NUMBER COMMA NUMBER COMMA NUMBER COMMA
		NUMBER COMMA NUMBER COMMA NUMBER COMMA NUMBER COMMA
		NUMBER COMMA NUMBER COMMA NUMBER COMMA NUMBER COMMA
		NUMBER COMMA NUMBER COMMA NUMBER COMMA NUMBER COMMA
		NUMBER COMMA NUMBER COMMA NUMBER COMMA NUMBER COMMA
		NUMBER
		{
#ifdef INET6
			char *a, *p;

			memset(&data_dest, 0, sizeof(data_dest));
			data_dest.su_len = sizeof(struct sockaddr_in6);
			data_dest.su_family = AF_INET6;
			p = (char *)&data_dest.su_port;
			p[0] = $39.i; p[1] = $41.i;
			a = (char *)&data_dest.si_su.su_sin6.sin6_addr;
			a[0] = $5.i; a[1] = $7.i; a[2] = $9.i; a[3] = $11.i;
			a[4] = $13.i; a[5] = $15.i; a[6] = $17.i; a[7] = $19.i;
			a[8] = $21.i; a[9] = $23.i; a[10] = $25.i; a[11] = $27.i;
			a[12] = $29.i; a[13] = $31.i; a[14] = $33.i; a[15] = $35.i;
			if (his_addr.su_family == AF_INET6) {
				/* XXX: more sanity checks! */
				data_dest.su_scope_id = his_addr.su_scope_id;
			}
#else
			memset(&data_dest, 0, sizeof(data_dest));
#endif /* INET6 */
			/* reject invalid LPRT command */
			if ($1.i != 6 || $3.i != 16 || $37.i != 2)
				memset(&data_dest, 0, sizeof(data_dest));
		}
	;

form_code
	: N
		{
			$$ = FORM_N;
		}

	| T
		{
			$$ = FORM_T;
		}

	| C
		{
			$$ = FORM_C;
		}
	;

type_code
	: A
		{
			cmd_type = TYPE_A;
			cmd_form = FORM_N;
		}

	| A SP form_code
		{
			cmd_type = TYPE_A;
			cmd_form = $3;
		}

	| E
		{
			cmd_type = TYPE_E;
			cmd_form = FORM_N;
		}

	| E SP form_code
		{
			cmd_type = TYPE_E;
			cmd_form = $3;
		}

	| I
		{
			cmd_type = TYPE_I;
		}

	| L
		{
			cmd_type = TYPE_L;
			cmd_bytesz = NBBY;
		}

	| L SP byte_size
		{
			cmd_type = TYPE_L;
			cmd_bytesz = $3;
		}

		/* this is for a bug in the BBN ftp */
	| L byte_size
		{
			cmd_type = TYPE_L;
			cmd_bytesz = $2;
		}
	;

struct_code
	: F
		{
			$$ = STRU_F;
		}

	| R
		{
			$$ = STRU_R;
		}

	| P
		{
			$$ = STRU_P;
		}
	;

mode_code
	: S
		{
			$$ = MODE_S;
		}

	| B
		{
			$$ = MODE_B;
		}

	| C
		{
			$$ = MODE_C;
		}
	;

pathname
	: pathstring
		{
			/*
			 * Problem: this production is used for all pathname
			 * processing, but only gives a 550 error reply.
			 * This is a valid reply in some cases but not in
			 * others.
			 */
			if (logged_in && $1 && *$1 == '~') {
				char	*path, *home, *result;
				size_t	len;

				path = strchr($1 + 1, '/');
				if (path != NULL)
					*path++ = '\0';
				if ($1[1] == '\0')
					home = homedir;
				else {
					struct passwd	*hpw;

					if ((hpw = getpwnam($1 + 1)) != NULL)
						home = hpw->pw_dir;
					else
						home = $1;
				}
				len = strlen(home) + 1;
				if (path != NULL)
					len += strlen(path) + 1;
				if ((result = malloc(len)) == NULL)
					fatal("Local resource failure: malloc");
				strlcpy(result, home, len);
				if (path != NULL) {
					strlcat(result, "/", len);
					strlcat(result, path, len);
				}
				$$ = result;
				free($1);
			} else
				$$ = $1;
		}
	;

pathstring
	: STRING
	;

octal_number
	: NUMBER
		{
			int ret, dec, multby, digit;

			/*
			 * Convert a number that was read as decimal number
			 * to what it would be if it had been read as octal.
			 */
			dec = $1.i;
			multby = 1;
			ret = 0;
			while (dec) {
				digit = dec%10;
				if (digit > 7) {
					ret = -1;
					break;
				}
				ret += digit * multby;
				multby *= 8;
				dec /= 10;
			}
			$$ = ret;
		}
	;

mechanism_name
	: STRING
	;

base64data
	: STRING
	;

prot_code
	: STRING
	;

decimal_integer
	: NUMBER
		{
			$$ = $1.i;
		}
	;

check_login
	: /* empty */
		{
			if (logged_in)
				$$ = 1;
			else {
				reply(530, "Please login with USER and PASS.");
				$$ = 0;
				hasyyerrored = 1;
			}
		}
	;

%%

#define	CMD	0	/* beginning of command */
#define	ARGS	1	/* expect miscellaneous arguments */
#define	STR1	2	/* expect SP followed by STRING */
#define	STR2	3	/* expect STRING */
#define	OSTR	4	/* optional SP then STRING */
#define	ZSTR1	5	/* SP then optional STRING */
#define	ZSTR2	6	/* optional STRING after SP */
#define	SITECMD	7	/* SITE command */
#define	NSTR	8	/* Number followed by a string */
#define NOARGS	9	/* No arguments allowed */
#define EOLN	10	/* End of line */

struct tab cmdtab[] = {
				/* From RFC 959, in order defined (5.3.1) */
	{ "USER", USER, STR1,	1,	"<sp> username" },
	{ "PASS", PASS, ZSTR1,	1,	"<sp> password" },
	{ "ACCT", ACCT, STR1,	0,	"(specify account)" },
	{ "CWD",  CWD,  OSTR,	1,	"[ <sp> directory-name ]" },
	{ "CDUP", CDUP, NOARGS,	1,	"(change to parent directory)" },
	{ "SMNT", SMNT, ARGS,	0,	"(structure mount)" },
	{ "QUIT", QUIT, NOARGS,	1,	"(terminate service)" },
	{ "REIN", REIN, NOARGS,	0,	"(reinitialize server state)" },
	{ "PORT", PORT, ARGS,	1,	"<sp> b0, b1, b2, b3, b4, b5" },
	{ "LPRT", LPRT, ARGS,	1,	"<sp> af, hal, h1, h2, h3,..., pal, p1, p2..." },
	{ "EPRT", EPRT, STR1,	1,	"<sp> |af|addr|port|" },
	{ "PASV", PASV, NOARGS,	1,	"(set server in passive mode)" },
	{ "LPSV", LPSV, ARGS,	1,	"(set server in passive mode)" },
	{ "EPSV", EPSV, ARGS,	1,	"[<sp> af|ALL]" },
	{ "TYPE", TYPE, ARGS,	1,	"<sp> [ A | E | I | L ]" },
	{ "STRU", STRU, ARGS,	1,	"(specify file structure)" },
	{ "MODE", MODE, ARGS,	1,	"(specify transfer mode)" },
	{ "RETR", RETR, STR1,	1,	"<sp> file-name" },
	{ "STOR", STOR, STR1,	1,	"<sp> file-name" },
	{ "STOU", STOU, STR1,	1,	"<sp> file-name" },
	{ "APPE", APPE, STR1,	1,	"<sp> file-name" },
	{ "ALLO", ALLO, ARGS,	1,	"allocate storage (vacuously)" },
	{ "REST", REST, ARGS,	1,	"<sp> offset (restart command)" },
	{ "RNFR", RNFR, STR1,	1,	"<sp> file-name" },
	{ "RNTO", RNTO, STR1,	1,	"<sp> file-name" },
	{ "ABOR", ABOR, NOARGS,	4,	"(abort operation)" },
	{ "DELE", DELE, STR1,	1,	"<sp> file-name" },
	{ "RMD",  RMD,  STR1,	1,	"<sp> path-name" },
	{ "MKD",  MKD,  STR1,	1,	"<sp> path-name" },
	{ "PWD",  PWD,  NOARGS,	1,	"(return current directory)" },
	{ "LIST", LIST, OSTR,	1,	"[ <sp> path-name ]" },
	{ "NLST", NLST, OSTR,	1,	"[ <sp> path-name ]" },
	{ "SITE", SITE, SITECMD, 1,	"site-cmd [ <sp> arguments ]" },
	{ "SYST", SYST, NOARGS,	1,	"(get type of operating system)" },
	{ "STAT", STAT, OSTR,	4,	"[ <sp> path-name ]" },
	{ "HELP", HELP, OSTR,	1,	"[ <sp> <string> ]" },
	{ "NOOP", NOOP, NOARGS,	2,	"" },

				/* From RFC 2228, in order defined */
	{ "AUTH", AUTH, STR1,	1,	"<sp> mechanism-name" },
	{ "ADAT", ADAT, STR1,	1,	"<sp> base-64-data" },
	{ "PROT", PROT, STR1,	1,	"<sp> prot-code" },
	{ "PBSZ", PBSZ, ARGS,	1,	"<sp> decimal-integer" },
	{ "CCC",  CCC,  NOARGS,	1,	"(Disable data protection)" },
	{ "MIC",  MIC,  STR1,	4,	"<sp> base64data" },
	{ "CONF", CONF, STR1,	4,	"<sp> base64data" },
	{ "ENC",  ENC,  STR1,	4,	"<sp> base64data" },

				/* From RFC 2389, in order defined */
	{ "FEAT", FEAT, NOARGS,	1,	"(display extended features)" },
	{ "OPTS", OPTS, STR1,	1,	"<sp> command [ <sp> options ]" },

				/* from draft-ietf-ftpext-mlst-11 */
	{ "MDTM", MDTM, OSTR,	1,	"<sp> path-name" },
	{ "SIZE", SIZE, OSTR,	1,	"<sp> path-name" },
	{ "MLST", MLST, OSTR,	2,	"[ <sp> path-name ]" },
	{ "MLSD", MLSD, OSTR,	1,	"[ <sp> directory-name ]" },

				/* obsolete commands */
	{ "MAIL", MAIL, OSTR,	0,	"(mail to user)" },
	{ "MLFL", MLFL, OSTR,	0,	"(mail file)" },
	{ "MRCP", MRCP, STR1,	0,	"(mail recipient)" },
	{ "MRSQ", MRSQ, OSTR,	0,	"(mail recipient scheme question)" },
	{ "MSAM", MSAM, OSTR,	0,	"(mail send to terminal and mailbox)" },
	{ "MSND", MSND, OSTR,	0,	"(mail send to terminal)" },
	{ "MSOM", MSOM, OSTR,	0,	"(mail send to terminal or mailbox)" },
	{ "XCUP", CDUP, NOARGS,	1,	"(change to parent directory)" },
	{ "XCWD", CWD,  OSTR,	1,	"[ <sp> directory-name ]" },
	{ "XMKD", MKD,  STR1,	1,	"<sp> path-name" },
	{ "XPWD", PWD,  NOARGS,	1,	"(return current directory)" },
	{ "XRMD", RMD,  STR1,	1,	"<sp> path-name" },

	{  NULL,  0,	0,	0,	0 }
};

struct tab sitetab[] = {
	{ "CHMOD",	CHMOD,	NSTR,	1,	"<sp> mode <sp> file-name" },
	{ "HELP",	HELP,	OSTR,	1,	"[ <sp> <string> ]" },
	{ "IDLE",	IDLE,	ARGS,	1,	"[ <sp> maximum-idle-time ]" },
	{ "RATEGET",	RATEGET,OSTR,	1,	"[ <sp> get-throttle-rate ]" },
	{ "RATEPUT",	RATEPUT,OSTR,	1,	"[ <sp> put-throttle-rate ]" },
	{ "UMASK",	UMASK,	ARGS,	1,	"[ <sp> umask ]" },
	{ NULL,		0,	0,	0,	NULL }
};

/*
 * Check if a filename is allowed to be modified (isupload == 0) or
 * uploaded (isupload == 1), and if necessary, check the filename is `sane'.
 * If the filename is NULL, fail.
 * If the filename is "", don't do the sane name check.
 */
static int
check_write(const char *file, int isupload)
{
	if (file == NULL)
		return (0);
	if (! logged_in) {
		reply(530, "Please login with USER and PASS.");
		return (0);
	}
		/* checking modify */
	if (! isupload && ! CURCLASS_FLAGS_ISSET(modify)) {
		reply(502, "No permission to use this command.");
		return (0);
	}
		/* checking upload */
	if (isupload && ! CURCLASS_FLAGS_ISSET(upload)) {
		reply(502, "No permission to use this command.");
		return (0);
	}

		/* checking sanenames */
	if (file[0] != '\0' && CURCLASS_FLAGS_ISSET(sanenames)) {
		const char *p;

		if (file[0] == '.')
			goto insane_name;
		for (p = file; *p; p++) {
			if (isalnum((unsigned char)*p) || *p == '-' || *p == '+' ||
			    *p == ',' || *p == '.' || *p == '_')
				continue;
 insane_name:
			reply(553, "File name `%s' not allowed.", file);
			return (0);
		}
	}
	return (1);
}

struct tab *
lookup(struct tab *p, const char *cmd)
{

	for (; p->name != NULL; p++)
		if (strcasecmp(cmd, p->name) == 0)
			return (p);
	return (0);
}

#include <arpa/telnet.h>

/*
 * getline - a hacked up version of fgets to ignore TELNET escape codes.
 */
char *
getline(char *s, int n, FILE *iop)
{
	int c;
	char *cs;

	cs = s;
/* tmpline may contain saved command from urgent mode interruption */
	for (c = 0; tmpline[c] != '\0' && --n > 0; ++c) {
		*cs++ = tmpline[c];
		if (tmpline[c] == '\n') {
			*cs++ = '\0';
			if (ftpd_debug)
				syslog(LOG_DEBUG, "command: %s", s);
			tmpline[0] = '\0';
			return(s);
		}
		if (c == 0)
			tmpline[0] = '\0';
	}
	while ((c = getc(iop)) != EOF) {
		total_bytes++;
		total_bytes_in++;
		c &= 0377;
		if (c == IAC) {
		    if ((c = getc(iop)) != EOF) {
			total_bytes++;
			total_bytes_in++;
			c &= 0377;
			switch (c) {
			case WILL:
			case WONT:
				c = getc(iop);
				total_bytes++;
				total_bytes_in++;
				cprintf(stdout, "%c%c%c", IAC, DONT, 0377&c);
				(void) fflush(stdout);
				continue;
			case DO:
			case DONT:
				c = getc(iop);
				total_bytes++;
				total_bytes_in++;
				cprintf(stdout, "%c%c%c", IAC, WONT, 0377&c);
				(void) fflush(stdout);
				continue;
			case IAC:
				break;
			default:
				continue;	/* ignore command */
			}
		    }
		}
		*cs++ = c;
		if (--n <= 0 || c == '\n')
			break;
	}
	if (c == EOF && cs == s)
		return (NULL);
	*cs++ = '\0';
	if (ftpd_debug) {
		if ((curclass.type != CLASS_GUEST &&
		    strncasecmp(s, "PASS ", 5) == 0) ||
		    strncasecmp(s, "ACCT ", 5) == 0) {
			/* Don't syslog passwords */
			syslog(LOG_DEBUG, "command: %.4s ???", s);
		} else {
			char *cp;
			int len;

			/* Don't syslog trailing CR-LF */
			len = strlen(s);
			cp = s + len - 1;
			while (cp >= s && (*cp == '\n' || *cp == '\r')) {
				--cp;
				--len;
			}
			syslog(LOG_DEBUG, "command: %.*s", len, s);
		}
	}
	return (s);
}

void
ftp_handle_line(char *cp)
{

	cmdp = cp;
	yyparse();
}

void
ftp_loop(void)
{

	while (1) {
		(void) alarm(curclass.timeout);
		if (getline(cbuf, sizeof(cbuf)-1, stdin) == NULL) {
			reply(221, "You could at least say goodbye.");
			dologout(0);
		}
		(void) alarm(0);
		ftp_handle_line(cbuf);
	}
	/*NOTREACHED*/
}

int
yylex(void)
{
	static int cpos, state;
	char *cp, *cp2;
	struct tab *p;
	int n;
	char c;

	switch (state) {

	case CMD:
		hasyyerrored = 0;
		if ((cp = strchr(cmdp, '\r'))) {
			*cp = '\0';
#if HAVE_SETPROCTITLE
			if (strncasecmp(cmdp, "PASS", 4) != 0 &&
			    strncasecmp(cmdp, "ACCT", 4) != 0)
				setproctitle("%s: %s", proctitle, cmdp);
#endif /* HAVE_SETPROCTITLE */
			*cp++ = '\n';
			*cp = '\0';
		}
		if ((cp = strpbrk(cmdp, " \n")))
			cpos = cp - cmdp;
		if (cpos == 0)
			cpos = 4;
		c = cmdp[cpos];
		cmdp[cpos] = '\0';
		p = lookup(cmdtab, cmdp);
		cmdp[cpos] = c;
		if (p != NULL) {
			if (is_oob && ! CMD_OOB(p)) {
				/* command will be handled in-band */
				return (0);
			} else if (! CMD_IMPLEMENTED(p)) {
				reply(502, "%s command not implemented.",
				    p->name);
				hasyyerrored = 1;
				break;
			}
			state = p->state;
			yylval.s = p->name;
			return (p->token);
		}
		break;

	case SITECMD:
		if (cmdp[cpos] == ' ') {
			cpos++;
			return (SP);
		}
		cp = &cmdp[cpos];
		if ((cp2 = strpbrk(cp, " \n")))
			cpos = cp2 - cmdp;
		c = cmdp[cpos];
		cmdp[cpos] = '\0';
		p = lookup(sitetab, cp);
		cmdp[cpos] = c;
		if (p != NULL) {
			if (!CMD_IMPLEMENTED(p)) {
				reply(502, "SITE %s command not implemented.",
				    p->name);
				hasyyerrored = 1;
				break;
			}
			state = p->state;
			yylval.s = p->name;
			return (p->token);
		}
		break;

	case OSTR:
		if (cmdp[cpos] == '\n') {
			state = EOLN;
			return (CRLF);
		}
		/* FALLTHROUGH */

	case STR1:
	case ZSTR1:
	dostr1:
		if (cmdp[cpos] == ' ') {
			cpos++;
			state = state == OSTR ? STR2 : state+1;
			return (SP);
		}
		break;

	case ZSTR2:
		if (cmdp[cpos] == '\n') {
			state = EOLN;
			return (CRLF);
		}
		/* FALLTHROUGH */

	case STR2:
		cp = &cmdp[cpos];
		n = strlen(cp);
		cpos += n - 1;
		/*
		 * Make sure the string is nonempty and \n terminated.
		 */
		if (n > 1 && cmdp[cpos] == '\n') {
			cmdp[cpos] = '\0';
			yylval.s = ftpd_strdup(cp);
			cmdp[cpos] = '\n';
			state = ARGS;
			return (STRING);
		}
		break;

	case NSTR:
		if (cmdp[cpos] == ' ') {
			cpos++;
			return (SP);
		}
		if (isdigit((unsigned char)cmdp[cpos])) {
			cp = &cmdp[cpos];
			while (isdigit((unsigned char)cmdp[++cpos]))
				;
			c = cmdp[cpos];
			cmdp[cpos] = '\0';
			yylval.u.i = atoi(cp);
			cmdp[cpos] = c;
			state = STR1;
			return (NUMBER);
		}
		state = STR1;
		goto dostr1;

	case ARGS:
		if (isdigit((unsigned char)cmdp[cpos])) {
			cp = &cmdp[cpos];
			while (isdigit((unsigned char)cmdp[++cpos]))
				;
			c = cmdp[cpos];
			cmdp[cpos] = '\0';
			yylval.u.i = atoi(cp);
			yylval.u.ll = STRTOLL(cp, (char **)NULL, 10);
			cmdp[cpos] = c;
			return (NUMBER);
		}
		if (strncasecmp(&cmdp[cpos], "ALL", 3) == 0
		    && !isalnum((unsigned char)cmdp[cpos + 3])) {
			cpos += 3;
			return (ALL);
		}
		switch (cmdp[cpos++]) {

		case '\n':
			state = EOLN;
			return (CRLF);

		case ' ':
			return (SP);

		case ',':
			return (COMMA);

		case 'A':
		case 'a':
			return (A);

		case 'B':
		case 'b':
			return (B);

		case 'C':
		case 'c':
			return (C);

		case 'E':
		case 'e':
			return (E);

		case 'F':
		case 'f':
			return (F);

		case 'I':
		case 'i':
			return (I);

		case 'L':
		case 'l':
			return (L);

		case 'N':
		case 'n':
			return (N);

		case 'P':
		case 'p':
			return (P);

		case 'R':
		case 'r':
			return (R);

		case 'S':
		case 's':
			return (S);

		case 'T':
		case 't':
			return (T);

		}
		break;

	case NOARGS:
		if (cmdp[cpos] == '\n') {
			state = EOLN;
			return (CRLF);
		}
		c = cmdp[cpos];
		cmdp[cpos] = '\0';
		reply(501, "'%s' command does not take any arguments.", cmdp);
		hasyyerrored = 1;
		cmdp[cpos] = c;
		break;

	case EOLN:
		state = CMD;
		return (0);

	default:
		fatal("Unknown state in scanner.");
	}
	yyerror(NULL);
	state = CMD;
	return (0);
}

/* ARGSUSED */
void
yyerror(char *s)
{
	char *cp;

	if (hasyyerrored || is_oob)
		return;
	if ((cp = strchr(cmdp,'\n')) != NULL)
		*cp = '\0';
	reply(500, "'%s': command not understood.", cmdp);
	hasyyerrored = 1;
}

static void
help(struct tab *ctab, const char *s)
{
	struct tab *c;
	int width, NCMDS;
	char *htype;

	if (ctab == sitetab)
		htype = "SITE ";
	else
		htype = "";
	width = 0, NCMDS = 0;
	for (c = ctab; c->name != NULL; c++) {
		int len = strlen(c->name);

		if (len > width)
			width = len;
		NCMDS++;
	}
	width = (width + 8) &~ 7;
	if (s == 0) {
		int i, j, w;
		int columns, lines;

		reply(-214, "%s", "");
		reply(0, "The following %scommands are recognized.", htype);
		reply(0, "(`-' = not implemented, `+' = supports options)");
		columns = 76 / width;
		if (columns == 0)
			columns = 1;
		lines = (NCMDS + columns - 1) / columns;
		for (i = 0; i < lines; i++) {
			cprintf(stdout, "    ");
			for (j = 0; j < columns; j++) {
				c = ctab + j * lines + i;
				cprintf(stdout, "%s", c->name);
				w = strlen(c->name);
				if (! CMD_IMPLEMENTED(c)) {
					CPUTC('-', stdout);
					w++;
				}
				if (CMD_HAS_OPTIONS(c)) {
					CPUTC('+', stdout);
					w++;
				}
				if (c + lines >= &ctab[NCMDS])
					break;
				while (w < width) {
					CPUTC(' ', stdout);
					w++;
				}
			}
			cprintf(stdout, "\r\n");
		}
		(void) fflush(stdout);
		reply(214, "Direct comments to ftp-bugs@%s.", hostname);
		return;
	}
	c = lookup(ctab, s);
	if (c == (struct tab *)0) {
		reply(502, "Unknown command '%s'.", s);
		return;
	}
	if (CMD_IMPLEMENTED(c))
		reply(214, "Syntax: %s%s %s", htype, c->name, c->help);
	else
		reply(504, "%s%-*s\t%s; not implemented.", htype, width,
		    c->name, c->help);
}

/*
 * Check that the structures used for a PORT, LPRT or EPRT command are
 * valid (data_dest, his_addr), and if necessary, detect ftp bounce attacks.
 * If family != -1 check that his_addr.su_family == family.
 */
static void
port_check(const char *cmd, int family)
{
	char h1[NI_MAXHOST], h2[NI_MAXHOST];
	char s1[NI_MAXHOST], s2[NI_MAXHOST];
#ifdef NI_WITHSCOPEID
	const int niflags = NI_NUMERICHOST | NI_NUMERICSERV | NI_WITHSCOPEID;
#else
	const int niflags = NI_NUMERICHOST | NI_NUMERICSERV;
#endif

	if (epsvall) {
		reply(501, "%s disallowed after EPSV ALL", cmd);
		return;
	}

	if (family != -1 && his_addr.su_family != family) {
 port_check_fail:
		reply(500, "Illegal %s command rejected", cmd);
		return;
	}

	if (data_dest.su_family != his_addr.su_family)
		goto port_check_fail;

			/* be paranoid, if told so */
	if (CURCLASS_FLAGS_ISSET(checkportcmd)) {
#ifdef INET6
		/*
		 * be paranoid, there are getnameinfo implementation that does
		 * not present scopeid portion
		 */
		if (data_dest.su_family == AF_INET6 &&
		    data_dest.su_scope_id != his_addr.su_scope_id)
			goto port_check_fail;
#endif

		if (getnameinfo((struct sockaddr *)&data_dest, data_dest.su_len,
		    h1, sizeof(h1), s1, sizeof(s1), niflags))
			goto port_check_fail;
		if (getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
		    h2, sizeof(h2), s2, sizeof(s2), niflags))
			goto port_check_fail;

		if (atoi(s1) < IPPORT_RESERVED || strcmp(h1, h2) != 0)
			goto port_check_fail;
	}

	usedefault = 0;
	if (pdata >= 0) {
		(void) close(pdata);
		pdata = -1;
	}
	reply(200, "%s command successful.", cmd);
}