ftpcmd.y revision 1.74 
1/*	$OpenBSD: ftpcmd.y,v 1.74 2023/03/08 04:43:05 guenther Exp $	*/
2/*	$NetBSD: ftpcmd.y,v 1.7 1996/04/08 19:03:11 jtc Exp $	*/
3
4/*
5 * Copyright (c) 1985, 1988, 1993, 1994
6 *	The Regents of the University of California.  All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the University nor the names of its contributors
17 *    may be used to endorse or promote products derived from this software
18 *    without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 *
32 *	@(#)ftpcmd.y	8.3 (Berkeley) 4/6/94
33 */
34
35/*
36 * Grammar for FTP commands.
37 * See RFC 959.
38 */
39
40%{
41
42#include <sys/types.h>
43#include <sys/socket.h>
44#include <sys/stat.h>
45
46#include <netinet/in.h>
47#include <arpa/ftp.h>
48
49#include <ctype.h>
50#include <errno.h>
51#include <glob.h>
52#include <pwd.h>
53#include <signal.h>
54#include <stdio.h>
55#include <stdlib.h>
56#include <string.h>
57#include <syslog.h>
58#include <time.h>
59#include <unistd.h>
60#include <netdb.h>
61#include <limits.h>
62
63#include "monitor.h"
64#include "extern.h"
65
66extern	union sockunion data_dest;
67extern	int logged_in;
68extern	struct passwd *pw;
69extern	int guest;
70extern	int logging;
71extern	int type;
72extern	int form;
73extern	int debug;
74extern	int timeout;
75extern	int maxtimeout;
76extern  int pdata;
77extern	char hostname[], remotehost[];
78extern	char proctitle[];
79extern	int usedefault;
80extern  int transflag;
81extern  char tmpline[];
82extern	int portcheck;
83extern	union sockunion his_addr;
84extern	int umaskchange;
85
86off_t	restart_point;
87
88static	int cmd_type;
89static	int cmd_form;
90static	int cmd_bytesz;
91static	int state;
92static	int quit;
93char	cbuf[512];
94char	*fromname;
95
96%}
97
98%union {
99	int	i;
100	off_t	o;
101	char   *s;
102}
103
104%token
105	A	B	C	E	F	I
106	L	N	P	R	S	T
107
108	SP	CRLF	COMMA	ALL
109
110	USER	PASS	ACCT	REIN	QUIT	PORT
111	PASV	TYPE	STRU	MODE	RETR	STOR
112	APPE	MLFL	MAIL	MSND	MSOM	MSAM
113	MRSQ	MRCP	ALLO	REST	RNFR	RNTO
114	ABOR	DELE	CWD	LIST	NLST	SITE
115	STAT	HELP	NOOP	MKD	RMD	PWD
116	CDUP	STOU	SMNT	SYST	SIZE	MDTM
117
118	LPRT	LPSV	EPRT	EPSV
119
120	UMASK	IDLE	CHMOD
121
122	LEXERR
123
124%token	<s> STRING
125%token	<i> NUMBER
126%token	<o> BIGNUM
127
128%type	<i> check_login check_login_epsvall octal_number byte_size
129%type	<i> struct_code mode_code type_code form_code
130%type	<i> host_port host_long_port4 host_long_port6
131%type	<o> file_size
132%type	<s> pathstring pathname password username
133
134%start	cmd_list
135
136%%
137
138cmd_list
139	: /* empty */
140	| cmd_list cmd
141		{
142			if (fromname) {
143				free(fromname);
144				fromname = NULL;
145			}
146			restart_point = 0;
147		}
148	| cmd_list rcmd
149	;
150
151cmd
152	: USER SP username CRLF
153		{
154			monitor_user($3);
155			free($3);
156		}
157	| PASS SP password CRLF
158		{
159			quit = monitor_pass($3);
160			explicit_bzero($3, strlen($3));
161			free($3);
162
163			/* Terminate unprivileged pre-auth slave */
164			if (quit)
165				_exit(0);
166		}
167	| PORT check_login_epsvall SP host_port CRLF
168		{
169			if ($2) {
170				if ($4) {
171					usedefault = 1;
172					reply(500,
173					    "Illegal PORT rejected (range errors).");
174				} else if (portcheck &&
175				    ntohs(data_dest.su_sin.sin_port) < IPPORT_RESERVED) {
176					usedefault = 1;
177					reply(500,
178					    "Illegal PORT rejected (reserved port).");
179				} else if (portcheck &&
180				    memcmp(&data_dest.su_sin.sin_addr,
181				    &his_addr.su_sin.sin_addr,
182				    sizeof data_dest.su_sin.sin_addr)) {
183					usedefault = 1;
184					reply(500,
185					    "Illegal PORT rejected (address wrong).");
186				} else {
187					usedefault = 0;
188					if (pdata >= 0) {
189						(void) close(pdata);
190						pdata = -1;
191					}
192					reply(200, "PORT command successful.");
193				}
194			}
195		}
196	| LPRT check_login_epsvall SP host_long_port4 CRLF
197		{
198			if ($2) {
199				/* reject invalid host_long_port4 */
200				if ($4) {
201					reply(500,
202					    "Illegal LPRT command rejected");
203					usedefault = 1;
204				} else {
205					usedefault = 0;
206					if (pdata >= 0) {
207						(void) close(pdata);
208						pdata = -1;
209					}
210					reply(200, "LPRT command successful.");
211				}
212			}
213		}
214
215	| LPRT check_login_epsvall SP host_long_port6 CRLF
216		{
217			if ($2) {
218				/* reject invalid host_long_port6 */
219				if ($4) {
220					reply(500,
221					    "Illegal LPRT command rejected");
222					usedefault = 1;
223				} else {
224					usedefault = 0;
225					if (pdata >= 0) {
226						(void) close(pdata);
227						pdata = -1;
228					}
229					reply(200, "LPRT command successful.");
230				}
231			}
232		}
233
234	| EPRT check_login_epsvall SP STRING CRLF
235		{
236			if ($2)
237				extended_port($4);
238			free($4);
239		}
240
241	| PASV check_login_epsvall CRLF
242		{
243			if ($2)
244				passive();
245		}
246	| LPSV check_login_epsvall CRLF
247		{
248			if ($2)
249				long_passive("LPSV", PF_UNSPEC);
250		}
251	| EPSV check_login SP NUMBER CRLF
252		{
253			if ($2)
254				long_passive("EPSV", epsvproto2af($4));
255		}
256	| EPSV check_login SP ALL CRLF
257		{
258			if ($2) {
259				reply(200, "EPSV ALL command successful.");
260				epsvall++;
261			}
262		}
263	| EPSV check_login CRLF
264		{
265			if ($2)
266				long_passive("EPSV", PF_UNSPEC);
267		}
268	| TYPE check_login SP type_code CRLF
269		{
270			if ($2) {
271				switch (cmd_type) {
272
273				case TYPE_A:
274					if (cmd_form == FORM_N) {
275						reply(200, "Type set to A.");
276						type = cmd_type;
277						form = cmd_form;
278					} else
279						reply(504, "Form must be N.");
280					break;
281
282				case TYPE_E:
283					reply(504, "Type E not implemented.");
284					break;
285
286				case TYPE_I:
287					reply(200, "Type set to I.");
288					type = cmd_type;
289					break;
290
291				case TYPE_L:
292					if (cmd_bytesz == 8) {
293						reply(200,
294						    "Type set to L (byte size 8).");
295						    type = cmd_type;
296					} else
297						reply(504, "Byte size must be 8.");
298
299				}
300			}
301		}
302	| STRU check_login SP struct_code CRLF
303		{
304			if ($2) {
305				switch ($4) {
306
307				case STRU_F:
308					reply(200, "STRU F ok.");
309					break;
310
311				default:
312					reply(504, "Unimplemented STRU type.");
313				}
314			}
315		}
316	| MODE check_login SP mode_code CRLF
317		{
318			if ($2) {
319				switch ($4) {
320
321				case MODE_S:
322					reply(200, "MODE S ok.");
323					break;
324
325				default:
326					reply(502, "Unimplemented MODE type.");
327				}
328			}
329		}
330	| ALLO check_login SP NUMBER CRLF
331		{
332			if ($2) {
333				reply(202, "ALLO command ignored.");
334			}
335		}
336	| ALLO check_login SP NUMBER SP R SP NUMBER CRLF
337		{
338			if ($2) {
339				reply(202, "ALLO command ignored.");
340			}
341		}
342	| RETR check_login SP pathname CRLF
343		{
344			if ($2 && $4 != NULL)
345				retrieve(RET_FILE, $4);
346			if ($4 != NULL)
347				free($4);
348		}
349	| STOR check_login SP pathname CRLF
350		{
351			if ($2 && $4 != NULL)
352				store($4, "w", 0);
353			if ($4 != NULL)
354				free($4);
355		}
356	| APPE check_login SP pathname CRLF
357		{
358			if ($2 && $4 != NULL)
359				store($4, "a", 0);
360			if ($4 != NULL)
361				free($4);
362		}
363	| NLST check_login CRLF
364		{
365			if ($2)
366				send_file_list(".");
367		}
368	| NLST check_login SP STRING CRLF
369		{
370			if ($2 && $4 != NULL)
371				send_file_list($4);
372			free($4);
373		}
374	| LIST check_login CRLF
375		{
376			if ($2)
377				retrieve(RET_LIST, ".");
378		}
379	| LIST check_login SP pathname CRLF
380		{
381			if ($2 && $4 != NULL)
382				retrieve(RET_LIST, $4);
383			if ($4 != NULL)
384				free($4);
385		}
386	| STAT check_login SP pathname CRLF
387		{
388			if ($2 && $4 != NULL)
389				statfilecmd($4);
390			if ($4 != NULL)
391				free($4);
392		}
393	| STAT check_login CRLF
394		{
395			if ($2)
396				statcmd();
397		}
398	| DELE check_login SP pathname CRLF
399		{
400			if ($2 && $4 != NULL)
401				delete($4);
402			if ($4 != NULL)
403				free($4);
404		}
405	| RNTO check_login SP pathname CRLF
406		{
407			if ($2 && $4 != NULL) {
408				if (fromname) {
409					renamecmd(fromname, $4);
410					free(fromname);
411					fromname = NULL;
412				} else {
413					reply(503,
414					  "Bad sequence of commands.");
415				}
416			}
417			if ($4 != NULL)
418				free($4);
419		}
420	| ABOR check_login CRLF
421		{
422			if ($2)
423				reply(225, "ABOR command successful.");
424		}
425	| CWD check_login CRLF
426		{
427			if ($2)
428				cwd(pw->pw_dir);
429		}
430	| CWD check_login SP pathname CRLF
431		{
432			if ($2 && $4 != NULL)
433				cwd($4);
434			if ($4 != NULL)
435				free($4);
436		}
437	| HELP CRLF
438		{
439			help(cmdtab, NULL);
440		}
441	| HELP SP STRING CRLF
442		{
443			char *cp = $3;
444
445			if (strncasecmp(cp, "SITE", 4) == 0) {
446				cp = $3 + 4;
447				if (*cp == ' ')
448					cp++;
449				if (*cp)
450					help(sitetab, cp);
451				else
452					help(sitetab, NULL);
453			} else
454				help(cmdtab, $3);
455			free ($3);
456		}
457	| NOOP CRLF
458		{
459			reply(200, "NOOP command successful.");
460		}
461	| MKD check_login SP pathname CRLF
462		{
463			if ($2 && $4 != NULL)
464				makedir($4);
465			if ($4 != NULL)
466				free($4);
467		}
468	| RMD check_login SP pathname CRLF
469		{
470			if ($2 && $4 != NULL)
471				removedir($4);
472			if ($4 != NULL)
473				free($4);
474		}
475	| PWD check_login CRLF
476		{
477			if ($2)
478				pwd();
479		}
480	| CDUP check_login CRLF
481		{
482			if ($2)
483				cwd("..");
484		}
485	| SITE SP HELP CRLF
486		{
487			help(sitetab, NULL);
488		}
489	| SITE SP HELP SP STRING CRLF
490		{
491			help(sitetab, $5);
492			free ($5);
493		}
494	| SITE SP UMASK check_login CRLF
495		{
496			mode_t oldmask;
497
498			if ($4) {
499				oldmask = umask(0);
500				(void) umask(oldmask);
501				reply(200, "Current UMASK is %03o", oldmask);
502			}
503		}
504	| SITE SP UMASK check_login SP octal_number CRLF
505		{
506			mode_t oldmask;
507
508			if ($4) {
509				if (($6 == -1) || ($6 > 0777)) {
510					reply(501, "Bad UMASK value");
511				} else if (!umaskchange) {
512					reply(550,
513					    "No permission to change umask.");
514				} else {
515					oldmask = umask($6);
516					reply(200,
517					    "UMASK set to %03o (was %03o)",
518					    $6, oldmask);
519				}
520			}
521		}
522	| SITE SP CHMOD check_login SP octal_number SP pathname CRLF
523		{
524			if ($4 && ($8 != NULL)) {
525				if (($6 == -1) || ($6 > 0777))
526					reply(501,
527					    "CHMOD: Mode value must be between "
528					    "0 and 0777");
529				else if (!umaskchange)
530					reply(550,
531					    "No permission to change mode of %s.",
532					    $8);
533				else if (chmod($8, $6) == -1)
534					perror_reply(550, $8);
535				else
536					reply(200,
537					    "CHMOD command successful.");
538			}
539			if ($8 != NULL)
540				free($8);
541		}
542	| SITE SP check_login IDLE CRLF
543		{
544			if ($3)
545				reply(200,
546				    "Current IDLE time limit is %d "
547				    "seconds; max %d",
548				    timeout, maxtimeout);
549		}
550	| SITE SP check_login IDLE SP NUMBER CRLF
551		{
552			if ($3) {
553				if ($6 < 30 || $6 > maxtimeout) {
554					reply(501,
555					    "Maximum IDLE time must be between "
556					    "30 and %d seconds",
557					    maxtimeout);
558				} else {
559					timeout = $6;
560					(void) alarm((unsigned) timeout);
561					reply(200,
562					    "Maximum IDLE time set to %d seconds",
563					    timeout);
564				}
565			}
566		}
567	| STOU check_login SP pathname CRLF
568		{
569			if ($2 && $4 != NULL)
570				store($4, "w", 1);
571			if ($4 != NULL)
572				free($4);
573		}
574	| SYST check_login CRLF
575		{
576			if ($2)
577			reply(215, "UNIX Type: L8");
578		}
579
580		/*
581		 * SIZE is not in RFC959, but Postel has blessed it and
582		 * it will be in the updated RFC.
583		 *
584		 * Return size of file in a format suitable for
585		 * using with RESTART (we just count bytes).
586		 */
587	| SIZE check_login SP pathname CRLF
588		{
589			if ($2 && $4 != NULL)
590				sizecmd($4);
591			if ($4 != NULL)
592				free($4);
593		}
594
595		/*
596		 * MDTM is not in RFC959, but Postel has blessed it and
597		 * it will be in the updated RFC.
598		 *
599		 * Return modification time of file as an ISO 3307
600		 * style time. E.g. YYYYMMDDHHMMSS or YYYYMMDDHHMMSS.xxx
601		 * where xxx is the fractional second (of any precision,
602		 * not necessarily 3 digits)
603		 */
604	| MDTM check_login SP pathname CRLF
605		{
606			if ($2 && $4 != NULL) {
607				struct stat stbuf;
608				if (stat($4, &stbuf) == -1)
609					reply(550, "%s: %s",
610					    $4, strerror(errno));
611				else if (!S_ISREG(stbuf.st_mode)) {
612					reply(550, "%s: not a plain file.", $4);
613				} else {
614					struct tm *t;
615					t = gmtime(&stbuf.st_mtime);
616					reply(213,
617					    "%04d%02d%02d%02d%02d%02d",
618					    1900 + t->tm_year,
619					    t->tm_mon+1, t->tm_mday,
620					    t->tm_hour, t->tm_min, t->tm_sec);
621				}
622			}
623			if ($4 != NULL)
624				free($4);
625		}
626	| QUIT CRLF
627		{
628			reply(221, "Goodbye.");
629			dologout(0);
630		}
631	| error
632		{
633			yyclearin;		/* discard lookahead data */
634			yyerrok;		/* clear error condition */
635			state = 0;		/* reset lexer state */
636		}
637	;
638rcmd
639	: RNFR check_login SP pathname CRLF
640		{
641			restart_point = 0;
642			if ($2 && $4) {
643				if (fromname)
644					free(fromname);
645				fromname = renamefrom($4);
646				if (fromname == NULL)
647					free($4);
648			} else if ($4) {
649				free ($4);
650			}
651		}
652
653	| REST check_login SP file_size CRLF
654		{
655			if ($2) {
656				if (fromname) {
657					free(fromname);
658					fromname = NULL;
659				}
660				restart_point = $4;
661				reply(350, "Restarting at %lld. %s",
662				    (long long)restart_point,
663				    "Send STORE or RETRIEVE to initiate transfer.");
664			}
665		}
666	;
667
668username
669	: STRING
670	;
671
672password
673	: /* empty */
674		{
675			$$ = calloc(1, sizeof(char));
676		}
677	| STRING
678	;
679
680byte_size
681	: NUMBER
682	;
683
684file_size
685	: NUMBER
686		{
687			$$ = $1;
688		}
689	| BIGNUM
690		{
691			$$ = $1;
692		}
693	;
694
695host_port
696	: NUMBER COMMA NUMBER COMMA NUMBER COMMA NUMBER COMMA
697		NUMBER COMMA NUMBER
698		{
699			char *a, *p;
700
701			if ($1 < 0 || $1 > 255 || $3 < 0 || $3 > 255 ||
702			    $5 < 0 || $5 > 255 || $7 < 0 || $7 > 255 ||
703			    $9 < 0 || $9 > 255 || $11 < 0 || $11 > 255) {
704				$$ = 1;
705			} else {
706				data_dest.su_sin.sin_len = sizeof(struct sockaddr_in);
707				data_dest.su_sin.sin_family = AF_INET;
708				p = (char *)&data_dest.su_sin.sin_port;
709				p[0] = $9; p[1] = $11;
710				a = (char *)&data_dest.su_sin.sin_addr;
711				a[0] = $1; a[1] = $3; a[2] = $5; a[3] = $7;
712				$$ = 0;
713			}
714		}
715	;
716
717host_long_port4
718	: NUMBER COMMA NUMBER COMMA NUMBER COMMA NUMBER COMMA
719		NUMBER COMMA NUMBER COMMA NUMBER COMMA NUMBER COMMA
720		NUMBER
721		{
722			char *a, *p;
723
724			/* reject invalid LPRT command */
725			if ($1 != 4 || $3 != 4 ||
726			    $5 < 0 || $5 > 255 || $7 < 0 || $7 > 255 ||
727			    $9 < 0 || $9 > 255 || $11 < 0 || $11 > 255 ||
728			    $13 != 2 ||
729			    $15 < 0 || $15 > 255 || $17 < 0 || $17 > 255) {
730				$$ = 1;
731			} else {
732				data_dest.su_sin.sin_len =
733					sizeof(struct sockaddr_in);
734				data_dest.su_family = AF_INET;
735				p = (char *)&data_dest.su_port;
736				p[0] = $15; p[1] = $17;
737				a = (char *)&data_dest.su_sin.sin_addr;
738				a[0] = $5; a[1] = $7; a[2] = $9; a[3] = $11;
739				$$ = 0;
740			}
741		}
742	;
743
744host_long_port6
745	: NUMBER COMMA NUMBER COMMA NUMBER COMMA NUMBER COMMA
746		NUMBER COMMA NUMBER COMMA NUMBER COMMA NUMBER COMMA
747		NUMBER COMMA NUMBER COMMA NUMBER COMMA NUMBER COMMA
748		NUMBER COMMA NUMBER COMMA NUMBER COMMA NUMBER COMMA
749		NUMBER COMMA NUMBER COMMA NUMBER COMMA NUMBER COMMA
750		NUMBER
751		{
752			char *a, *p;
753
754			/* reject invalid LPRT command */
755			if ($1 != 6 || $3 != 16 ||
756			    $5 < 0 || $5 > 255 || $7 < 0 || $7 > 255 ||
757			    $9 < 0 || $9 > 255 || $11 < 0 || $11 > 255 ||
758			    $13 < 0 || $13 > 255 || $15 < 0 || $15 > 255 ||
759			    $17 < 0 || $17 > 255 || $19 < 0 || $19 > 255 ||
760			    $21 < 0 || $21 > 255 || $23 < 0 || $23 > 255 ||
761			    $25 < 0 || $25 > 255 || $27 < 0 || $27 > 255 ||
762			    $29 < 0 || $29 > 255 || $31 < 0 || $31 > 255 ||
763			    $33 < 0 || $33 > 255 || $35 < 0 || $35 > 255 ||
764			    $37 != 2 ||
765			    $39 < 0 || $39 > 255 || $41 < 0 || $41 > 255) {
766				$$ = 1;
767			} else {
768				data_dest.su_sin6.sin6_len =
769					sizeof(struct sockaddr_in6);
770				data_dest.su_family = AF_INET6;
771				p = (char *)&data_dest.su_port;
772				p[0] = $39; p[1] = $41;
773				a = (char *)&data_dest.su_sin6.sin6_addr;
774				 a[0] =  $5;  a[1] =  $7;
775				 a[2] =  $9;  a[3] = $11;
776				 a[4] = $13;  a[5] = $15;
777				 a[6] = $17;  a[7] = $19;
778				 a[8] = $21;  a[9] = $23;
779				a[10] = $25; a[11] = $27;
780				a[12] = $29; a[13] = $31;
781				a[14] = $33; a[15] = $35;
782				if (his_addr.su_family == AF_INET6) {
783					/* XXX more sanity checks! */
784					data_dest.su_sin6.sin6_scope_id =
785					    his_addr.su_sin6.sin6_scope_id;
786				}
787
788				$$ = 0;
789			}
790		}
791	;
792
793form_code
794	: N
795		{
796			$$ = FORM_N;
797		}
798	| T
799		{
800			$$ = FORM_T;
801		}
802	| C
803		{
804			$$ = FORM_C;
805		}
806	;
807
808type_code
809	: A
810		{
811			cmd_type = TYPE_A;
812			cmd_form = FORM_N;
813		}
814	| A SP form_code
815		{
816			cmd_type = TYPE_A;
817			cmd_form = $3;
818		}
819	| E
820		{
821			cmd_type = TYPE_E;
822			cmd_form = FORM_N;
823		}
824	| E SP form_code
825		{
826			cmd_type = TYPE_E;
827			cmd_form = $3;
828		}
829	| I
830		{
831			cmd_type = TYPE_I;
832		}
833	| L
834		{
835			cmd_type = TYPE_L;
836			cmd_bytesz = 8;
837		}
838	| L SP byte_size
839		{
840			cmd_type = TYPE_L;
841			cmd_bytesz = $3;
842		}
843		/* this is for a bug in the BBN ftp */
844	| L byte_size
845		{
846			cmd_type = TYPE_L;
847			cmd_bytesz = $2;
848		}
849	;
850
851struct_code
852	: F
853		{
854			$$ = STRU_F;
855		}
856	| R
857		{
858			$$ = STRU_R;
859		}
860	| P
861		{
862			$$ = STRU_P;
863		}
864	;
865
866mode_code
867	: S
868		{
869			$$ = MODE_S;
870		}
871	| B
872		{
873			$$ = MODE_B;
874		}
875	| C
876		{
877			$$ = MODE_C;
878		}
879	;
880
881pathname
882	: pathstring
883		{
884			/*
885			 * Problem: this production is used for all pathname
886			 * processing, but only gives a 550 error reply.
887			 * This is a valid reply in some cases but not in others.
888			 */
889			if (logged_in && $1 && strchr($1, '~') != NULL) {
890				glob_t gl;
891				int flags =
892				 GLOB_BRACE|GLOB_NOCHECK|GLOB_QUOTE|GLOB_TILDE;
893				char *pptr = $1;
894
895				/*
896				 * glob() will only find a leading ~, but
897				 * Netscape kindly puts a slash in front of
898				 * it for publish URLs.  There needs to be
899				 * a flag for glob() that expands tildes
900				 * anywhere in the string.
901				 */
902				if ((pptr[0] == '/') && (pptr[1] == '~'))
903					pptr++;
904
905				memset(&gl, 0, sizeof(gl));
906				if (glob(pptr, flags, NULL, &gl) ||
907				    gl.gl_pathc == 0) {
908					reply(550, "not found");
909					$$ = NULL;
910				} else {
911					$$ = strdup(gl.gl_pathv[0]);
912				}
913				globfree(&gl);
914				free($1);
915			} else
916				$$ = $1;
917		}
918	;
919
920pathstring
921	: STRING
922	;
923
924octal_number
925	: NUMBER
926		{
927			int ret, dec, multby, digit;
928
929			/*
930			 * Convert a number that was read as decimal number
931			 * to what it would be if it had been read as octal.
932			 */
933			dec = $1;
934			multby = 1;
935			ret = 0;
936			while (dec) {
937				digit = dec%10;
938				if (digit > 7) {
939					ret = -1;
940					break;
941				}
942				ret += digit * multby;
943				multby *= 8;
944				dec /= 10;
945			}
946			$$ = ret;
947		}
948	;
949
950
951check_login
952	: /* empty */
953		{
954			if (logged_in)
955				$$ = 1;
956			else {
957				reply(530, "Please login with USER and PASS.");
958				$$ = 0;
959				state = 0;
960				YYABORT;
961			}
962		}
963	;
964
965check_login_epsvall
966	: /* empty */
967		{
968			if (!logged_in) {
969				reply(530, "Please login with USER and PASS.");
970				$$ = 0;
971				state = 0;
972				YYABORT;
973			} else if (epsvall) {
974				reply(501, "the command is disallowed "
975				    "after EPSV ALL");
976				usedefault = 1;
977				$$ = 0;
978			} else
979				$$ = 1;
980		}
981	;
982
983%%
984
985#define	CMD	0	/* beginning of command */
986#define	ARGS	1	/* expect miscellaneous arguments */
987#define	STR1	2	/* expect SP followed by STRING */
988#define	STR2	3	/* expect STRING */
989#define	OSTR	4	/* optional SP then STRING */
990#define	ZSTR1	5	/* SP then optional STRING */
991#define	ZSTR2	6	/* optional STRING after SP */
992#define	SITECMD	7	/* SITE command */
993#define	NSTR	8	/* Number followed by a string */
994
995struct tab {
996	char	*name;
997	short	token;
998	short	state;
999	short	implemented;	/* 1 if command is implemented */
1000	char	*help;
1001};
1002
1003struct tab cmdtab[] = {		/* In order defined in RFC 765 */
1004	{ "USER", USER, STR1, 1,	"<sp> username" },
1005	{ "PASS", PASS, ZSTR1, 1,	"<sp> password" },
1006	{ "ACCT", ACCT, STR1, 0,	"(specify account)" },
1007	{ "SMNT", SMNT, ARGS, 0,	"(structure mount)" },
1008	{ "REIN", REIN, ARGS, 0,	"(reinitialize server state)" },
1009	{ "QUIT", QUIT, ARGS, 1,	"(terminate service)", },
1010	{ "PORT", PORT, ARGS, 1,	"<sp> b0, b1, b2, b3, b4" },
1011	{ "LPRT", LPRT, ARGS, 1,	"<sp> af, hal, h1, h2, h3,..., pal, p1, p2..." },
1012	{ "EPRT", EPRT, STR1, 1,	"<sp> |af|addr|port|" },
1013	{ "PASV", PASV, ARGS, 1,	"(set server in passive mode)" },
1014	{ "LPSV", LPSV, ARGS, 1,	"(set server in passive mode)" },
1015	{ "EPSV", EPSV, ARGS, 1,	"[<sp> af|ALL]" },
1016	{ "TYPE", TYPE, ARGS, 1,	"<sp> [ A | E | I | L ]" },
1017	{ "STRU", STRU, ARGS, 1,	"(specify file structure)" },
1018	{ "MODE", MODE, ARGS, 1,	"(specify transfer mode)" },
1019	{ "RETR", RETR, STR1, 1,	"<sp> file-name" },
1020	{ "STOR", STOR, STR1, 1,	"<sp> file-name" },
1021	{ "APPE", APPE, STR1, 1,	"<sp> file-name" },
1022	{ "MLFL", MLFL, OSTR, 0,	"(mail file)" },
1023	{ "MAIL", MAIL, OSTR, 0,	"(mail to user)" },
1024	{ "MSND", MSND, OSTR, 0,	"(mail send to terminal)" },
1025	{ "MSOM", MSOM, OSTR, 0,	"(mail send to terminal or mailbox)" },
1026	{ "MSAM", MSAM, OSTR, 0,	"(mail send to terminal and mailbox)" },
1027	{ "MRSQ", MRSQ, OSTR, 0,	"(mail recipient scheme question)" },
1028	{ "MRCP", MRCP, STR1, 0,	"(mail recipient)" },
1029	{ "ALLO", ALLO, ARGS, 1,	"allocate storage (vacuously)" },
1030	{ "REST", REST, ARGS, 1,	"<sp> offset (restart command)" },
1031	{ "RNFR", RNFR, STR1, 1,	"<sp> file-name" },
1032	{ "RNTO", RNTO, STR1, 1,	"<sp> file-name" },
1033	{ "ABOR", ABOR, ARGS, 1,	"(abort operation)" },
1034	{ "DELE", DELE, STR1, 1,	"<sp> file-name" },
1035	{ "CWD",  CWD,  OSTR, 1,	"[ <sp> directory-name ]" },
1036	{ "XCWD", CWD,	OSTR, 1,	"[ <sp> directory-name ]" },
1037	{ "LIST", LIST, OSTR, 1,	"[ <sp> path-name ]" },
1038	{ "NLST", NLST, OSTR, 1,	"[ <sp> path-name ]" },
1039	{ "SITE", SITE, SITECMD, 1,	"site-cmd [ <sp> arguments ]" },
1040	{ "SYST", SYST, ARGS, 1,	"(get type of operating system)" },
1041	{ "STAT", STAT, OSTR, 1,	"[ <sp> path-name ]" },
1042	{ "HELP", HELP, OSTR, 1,	"[ <sp> <string> ]" },
1043	{ "NOOP", NOOP, ARGS, 1,	"" },
1044	{ "MKD",  MKD,  STR1, 1,	"<sp> path-name" },
1045	{ "XMKD", MKD,  STR1, 1,	"<sp> path-name" },
1046	{ "RMD",  RMD,  STR1, 1,	"<sp> path-name" },
1047	{ "XRMD", RMD,  STR1, 1,	"<sp> path-name" },
1048	{ "PWD",  PWD,  ARGS, 1,	"(return current directory)" },
1049	{ "XPWD", PWD,  ARGS, 1,	"(return current directory)" },
1050	{ "CDUP", CDUP, ARGS, 1,	"(change to parent directory)" },
1051	{ "XCUP", CDUP, ARGS, 1,	"(change to parent directory)" },
1052	{ "STOU", STOU, STR1, 1,	"<sp> file-name" },
1053	{ "SIZE", SIZE, OSTR, 1,	"<sp> path-name" },
1054	{ "MDTM", MDTM, OSTR, 1,	"<sp> path-name" },
1055	{ NULL,   0,    0,    0,	0 }
1056};
1057
1058struct tab sitetab[] = {
1059	{ "UMASK", UMASK, ARGS, 1,	"[ <sp> umask ]" },
1060	{ "IDLE", IDLE, ARGS, 1,	"[ <sp> maximum-idle-time ]" },
1061	{ "CHMOD", CHMOD, NSTR, 1,	"<sp> mode <sp> file-name" },
1062	{ "HELP", HELP, OSTR, 1,	"[ <sp> <string> ]" },
1063	{ NULL,   0,    0,    0,	0 }
1064};
1065
1066static void	 help(struct tab *, char *);
1067static struct tab *
1068		 lookup(struct tab *, const char *);
1069static void	 sizecmd(const char *);
1070static int	 yylex(void);
1071
1072extern int epsvall;
1073
1074static struct tab *
1075lookup(struct tab *p, const char *cmd)
1076{
1077
1078	for (; p->name != NULL; p++)
1079		if (strcmp(cmd, p->name) == 0)
1080			return (p);
1081	return (NULL);
1082}
1083
1084#include <arpa/telnet.h>
1085
1086/*
1087 * get_line - a hacked up version of fgets to ignore TELNET escape codes.
1088 */
1089int
1090get_line(char *s, int n)
1091{
1092	int c;
1093	char *cs;
1094
1095	cs = s;
1096/* tmpline may contain saved command from urgent mode interruption */
1097	for (c = 0; tmpline[c] != '\0' && --n > 0; ++c) {
1098		*cs++ = tmpline[c];
1099		if (tmpline[c] == '\n') {
1100			*cs++ = '\0';
1101			if (debug)
1102				syslog(LOG_DEBUG, "command: %s", s);
1103			tmpline[0] = '\0';
1104			return(0);
1105		}
1106		if (c == 0)
1107			tmpline[0] = '\0';
1108	}
1109	while ((c = getc(stdin)) != EOF) {
1110		c &= 0377;
1111		if (c == IAC) {
1112		    if ((c = getc(stdin)) != EOF) {
1113			c &= 0377;
1114			switch (c) {
1115			case WILL:
1116			case WONT:
1117				c = getc(stdin);
1118				printf("%c%c%c", IAC, DONT, 0377&c);
1119				(void) fflush(stdout);
1120				continue;
1121			case DO:
1122			case DONT:
1123				c = getc(stdin);
1124				printf("%c%c%c", IAC, WONT, 0377&c);
1125				(void) fflush(stdout);
1126				continue;
1127			case IAC:
1128				break;
1129			default:
1130				continue;	/* ignore command */
1131			}
1132		    }
1133		}
1134		*cs++ = c;
1135		if (--n <= 0) {
1136			/*
1137			 * If command doesn't fit into buffer, discard the
1138			 * rest of the command and indicate truncation.
1139			 * This prevents the command to be split up into
1140			 * multiple commands.
1141			 */
1142			while (c != '\n' && (c = getc(stdin)) != EOF)
1143				;
1144			return (-2);
1145		}
1146		if (c == '\n')
1147			break;
1148	}
1149	if (c == EOF && cs == s)
1150		return (-1);
1151	*cs++ = '\0';
1152	if (debug) {
1153		if (!guest && strncasecmp("pass ", s, 5) == 0) {
1154			/* Don't syslog passwords */
1155			syslog(LOG_DEBUG, "command: %.5s ???", s);
1156		} else {
1157			char *cp;
1158			int len;
1159
1160			/* Don't syslog trailing CR-LF */
1161			len = strlen(s);
1162			cp = s + len - 1;
1163			while (cp >= s && (*cp == '\n' || *cp == '\r')) {
1164				--cp;
1165				--len;
1166			}
1167			syslog(LOG_DEBUG, "command: %.*s", len, s);
1168		}
1169	}
1170	return (0);
1171}
1172
1173void
1174toolong(int signo)
1175{
1176	struct syslog_data sdata = SYSLOG_DATA_INIT;
1177
1178	reply_r(421,
1179	    "Timeout (%d seconds): closing control connection.", timeout);
1180	if (logging)
1181		syslog_r(LOG_INFO, &sdata, "User %s timed out after %d seconds",
1182		    (pw ? pw -> pw_name : "unknown"), timeout);
1183	dologout(1);
1184}
1185
1186static int
1187yylex(void)
1188{
1189	static int cpos;
1190	char *cp, *cp2;
1191	struct tab *p;
1192	int n;
1193	char c;
1194
1195	for (;;) {
1196		switch (state) {
1197
1198		case CMD:
1199			(void) alarm((unsigned) timeout);
1200			n = get_line(cbuf, sizeof(cbuf)-1);
1201			if (n == -1) {
1202				reply(221, "You could at least say goodbye.");
1203				dologout(0);
1204			} else if (n == -2) {
1205				reply(500, "Command too long.");
1206				alarm(0);
1207				continue;
1208			}
1209			(void) alarm(0);
1210			if ((cp = strchr(cbuf, '\r'))) {
1211				*cp++ = '\n';
1212				*cp = '\0';
1213			}
1214			if (strncasecmp(cbuf, "PASS", 4) != 0) {
1215				if ((cp = strpbrk(cbuf, "\n"))) {
1216					c = *cp;
1217					*cp = '\0';
1218					setproctitle("%s: %s", proctitle, cbuf);
1219					*cp = c;
1220				}
1221			}
1222			if ((cp = strpbrk(cbuf, " \n")))
1223				cpos = cp - cbuf;
1224			if (cpos == 0)
1225				cpos = 4;
1226			c = cbuf[cpos];
1227			cbuf[cpos] = '\0';
1228			upper(cbuf);
1229			p = lookup(cmdtab, cbuf);
1230			cbuf[cpos] = c;
1231			if (p != NULL) {
1232				if (p->implemented == 0) {
1233					nack(p->name);
1234					return (LEXERR);
1235				}
1236				state = p->state;
1237				yylval.s = p->name;
1238				return (p->token);
1239			}
1240			break;
1241
1242		case SITECMD:
1243			if (cbuf[cpos] == ' ') {
1244				cpos++;
1245				return (SP);
1246			}
1247			cp = &cbuf[cpos];
1248			if ((cp2 = strpbrk(cp, " \n")))
1249				cpos = cp2 - cbuf;
1250			c = cbuf[cpos];
1251			cbuf[cpos] = '\0';
1252			upper(cp);
1253			p = lookup(sitetab, cp);
1254			cbuf[cpos] = c;
1255			if (p != NULL) {
1256				if (p->implemented == 0) {
1257					state = CMD;
1258					nack(p->name);
1259					return (LEXERR);
1260				}
1261				state = p->state;
1262				yylval.s = p->name;
1263				return (p->token);
1264			}
1265			state = CMD;
1266			break;
1267
1268		case OSTR:
1269			if (cbuf[cpos] == '\n') {
1270				state = CMD;
1271				return (CRLF);
1272			}
1273			/* FALLTHROUGH */
1274
1275		case STR1:
1276		case ZSTR1:
1277		dostr1:
1278			if (cbuf[cpos] == ' ') {
1279				cpos++;
1280				state = state == OSTR ? STR2 : state+1;
1281				return (SP);
1282			}
1283			break;
1284
1285		case ZSTR2:
1286			if (cbuf[cpos] == '\n') {
1287				state = CMD;
1288				return (CRLF);
1289			}
1290			/* FALLTHROUGH */
1291
1292		case STR2:
1293			cp = &cbuf[cpos];
1294			n = strlen(cp);
1295			cpos += n - 1;
1296			/*
1297			 * Make sure the string is nonempty and \n terminated.
1298			 */
1299			if (n > 1 && cbuf[cpos] == '\n') {
1300				cbuf[cpos] = '\0';
1301				yylval.s = strdup(cp);
1302				if (yylval.s == NULL)
1303					fatal("Ran out of memory.");
1304				cbuf[cpos] = '\n';
1305				state = ARGS;
1306				return (STRING);
1307			}
1308			break;
1309
1310		case NSTR:
1311			if (cbuf[cpos] == ' ') {
1312				cpos++;
1313				return (SP);
1314			}
1315			if (isdigit((unsigned char)cbuf[cpos])) {
1316				cp = &cbuf[cpos];
1317				while (isdigit((unsigned char)cbuf[++cpos]))
1318					;
1319				c = cbuf[cpos];
1320				cbuf[cpos] = '\0';
1321				yylval.i = atoi(cp);
1322				cbuf[cpos] = c;
1323				state = STR1;
1324				return (NUMBER);
1325			}
1326			state = STR1;
1327			goto dostr1;
1328
1329		case ARGS:
1330			if (isdigit((unsigned char)cbuf[cpos])) {
1331				long long llval;
1332
1333				cp = &cbuf[cpos];
1334				errno = 0;
1335				llval = strtoll(cp, &cp2, 10);
1336				if (llval < 0 ||
1337				    (errno == ERANGE && llval == LLONG_MAX))
1338					break;
1339
1340				cpos = (int)(cp2 - cbuf);
1341				if (llval > INT_MAX) {
1342					yylval.o = llval;
1343					return (BIGNUM);
1344				} else {
1345					yylval.i = (int)llval;
1346					return (NUMBER);
1347				}
1348			}
1349			if (strncasecmp(&cbuf[cpos], "ALL", 3) == 0 &&
1350			    !isalnum((unsigned char)cbuf[cpos + 3])) {
1351				cpos += 3;
1352				return ALL;
1353			}
1354			switch (cbuf[cpos++]) {
1355
1356			case '\n':
1357				state = CMD;
1358				return (CRLF);
1359
1360			case ' ':
1361				return (SP);
1362
1363			case ',':
1364				return (COMMA);
1365
1366			case 'A':
1367			case 'a':
1368				return (A);
1369
1370			case 'B':
1371			case 'b':
1372				return (B);
1373
1374			case 'C':
1375			case 'c':
1376				return (C);
1377
1378			case 'E':
1379			case 'e':
1380				return (E);
1381
1382			case 'F':
1383			case 'f':
1384				return (F);
1385
1386			case 'I':
1387			case 'i':
1388				return (I);
1389
1390			case 'L':
1391			case 'l':
1392				return (L);
1393
1394			case 'N':
1395			case 'n':
1396				return (N);
1397
1398			case 'P':
1399			case 'p':
1400				return (P);
1401
1402			case 'R':
1403			case 'r':
1404				return (R);
1405
1406			case 'S':
1407			case 's':
1408				return (S);
1409
1410			case 'T':
1411			case 't':
1412				return (T);
1413
1414			}
1415			break;
1416
1417		default:
1418			fatal("Unknown state in scanner.");
1419		}
1420		state = CMD;
1421		return (LEXERR);
1422	}
1423}
1424
1425void
1426upper(char *s)
1427{
1428	char *p;
1429
1430	for (p = s; *p; p++)
1431		*p = (char)toupper((unsigned char)*p);
1432}
1433
1434static void
1435help(struct tab *ctab, char *s)
1436{
1437	struct tab *c;
1438	int width, NCMDS;
1439	char *type;
1440
1441	if (ctab == sitetab)
1442		type = "SITE ";
1443	else
1444		type = "";
1445	width = 0, NCMDS = 0;
1446	for (c = ctab; c->name != NULL; c++) {
1447		int len = strlen(c->name);
1448
1449		if (len > width)
1450			width = len;
1451		NCMDS++;
1452	}
1453	width = (width + 8) &~ 7;
1454	if (s == NULL) {
1455		int i, j, w;
1456		int columns, lines;
1457
1458		lreply(214, "The following %scommands are recognized %s.",
1459		    type, "(* =>'s unimplemented)");
1460		columns = 76 / width;
1461		if (columns == 0)
1462			columns = 1;
1463		lines = (NCMDS + columns - 1) / columns;
1464		for (i = 0; i < lines; i++) {
1465			printf("   ");
1466			for (j = 0; j < columns; j++) {
1467				c = ctab + j * lines + i;
1468				printf("%s%c", c->name,
1469					c->implemented ? ' ' : '*');
1470				if (c + lines >= &ctab[NCMDS])
1471					break;
1472				w = strlen(c->name) + 1;
1473				while (w < width) {
1474					putchar(' ');
1475					w++;
1476				}
1477			}
1478			printf("\r\n");
1479		}
1480		(void) fflush(stdout);
1481		reply(214, "Direct comments to ftp-bugs@%s.", hostname);
1482		return;
1483	}
1484	upper(s);
1485	c = lookup(ctab, s);
1486	if (c == NULL) {
1487		reply(502, "Unknown command %s.", s);
1488		return;
1489	}
1490	if (c->implemented)
1491		reply(214, "Syntax: %s%s %s", type, c->name, c->help);
1492	else
1493		reply(214, "%s%-*s\t%s; unimplemented.", type, width,
1494		    c->name, c->help);
1495}
1496
1497static void
1498sizecmd(const char *filename)
1499{
1500	switch (type) {
1501	case TYPE_L:
1502	case TYPE_I: {
1503		struct stat stbuf;
1504		if (stat(filename, &stbuf) == -1 || !S_ISREG(stbuf.st_mode))
1505			reply(550, "%s: not a plain file.", filename);
1506		else
1507			reply(213, "%lld", (long long)stbuf.st_size);
1508		break; }
1509	case TYPE_A: {
1510		FILE *fin;
1511		int c;
1512		off_t count;
1513		struct stat stbuf;
1514		fin = fopen(filename, "r");
1515		if (fin == NULL) {
1516			perror_reply(550, filename);
1517			return;
1518		}
1519		if (fstat(fileno(fin), &stbuf) == -1 || !S_ISREG(stbuf.st_mode)) {
1520			reply(550, "%s: not a plain file.", filename);
1521			(void) fclose(fin);
1522			return;
1523		}
1524		if (stbuf.st_size > 10240) {
1525			reply(550, "%s: file too large for SIZE.", filename);
1526			(void) fclose(fin);
1527			return;
1528		}
1529
1530		count = 0;
1531		while((c = getc(fin)) != EOF) {
1532			if (c == '\n')	/* will get expanded to \r\n */
1533				count++;
1534			count++;
1535		}
1536		(void) fclose(fin);
1537
1538		reply(213, "%lld", (long long)count);
1539		break; }
1540	default:
1541		reply(504, "SIZE not implemented for Type %c.", "?AEIL"[type]);
1542	}
1543}
1544