xref: /netbsd-src/libexec/ftpd/ftpd.c (revision 8ac07aec990b9d2e483062509d0a9fa5b4f57cf2)
1 /*	$NetBSD: ftpd.c,v 1.183 2008/03/27 08:12:09 lukem Exp $	*/
2 
3 /*
4  * Copyright (c) 1997-2008 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Luke Mewburn.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *        This product includes software developed by the NetBSD
21  *        Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 /*
40  * Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994
41  *	The Regents of the University of California.  All rights reserved.
42  *
43  * Redistribution and use in source and binary forms, with or without
44  * modification, are permitted provided that the following conditions
45  * are met:
46  * 1. Redistributions of source code must retain the above copyright
47  *    notice, this list of conditions and the following disclaimer.
48  * 2. Redistributions in binary form must reproduce the above copyright
49  *    notice, this list of conditions and the following disclaimer in the
50  *    documentation and/or other materials provided with the distribution.
51  * 3. Neither the name of the University nor the names of its contributors
52  *    may be used to endorse or promote products derived from this software
53  *    without specific prior written permission.
54  *
55  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
56  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
57  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
58  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
59  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
60  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
61  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
62  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
63  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
64  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
65  * SUCH DAMAGE.
66  */
67 
68 /*
69  * Copyright (C) 1997 and 1998 WIDE Project.
70  * All rights reserved.
71  *
72  * Redistribution and use in source and binary forms, with or without
73  * modification, are permitted provided that the following conditions
74  * are met:
75  * 1. Redistributions of source code must retain the above copyright
76  *    notice, this list of conditions and the following disclaimer.
77  * 2. Redistributions in binary form must reproduce the above copyright
78  *    notice, this list of conditions and the following disclaimer in the
79  *    documentation and/or other materials provided with the distribution.
80  * 3. Neither the name of the project nor the names of its contributors
81  *    may be used to endorse or promote products derived from this software
82  *    without specific prior written permission.
83  *
84  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
85  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
86  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
87  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
88  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
89  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
90  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
91  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
92  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
93  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
94  * SUCH DAMAGE.
95  */
96 
97 #include <sys/cdefs.h>
98 #ifndef lint
99 __COPYRIGHT(
100 "@(#) Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994\n\
101 	The Regents of the University of California.  All rights reserved.\n");
102 #endif /* not lint */
103 
104 #ifndef lint
105 #if 0
106 static char sccsid[] = "@(#)ftpd.c	8.5 (Berkeley) 4/28/95";
107 #else
108 __RCSID("$NetBSD: ftpd.c,v 1.183 2008/03/27 08:12:09 lukem Exp $");
109 #endif
110 #endif /* not lint */
111 
112 /*
113  * FTP server.
114  */
115 #include <sys/param.h>
116 #include <sys/stat.h>
117 #include <sys/ioctl.h>
118 #include <sys/socket.h>
119 #include <sys/wait.h>
120 #include <sys/mman.h>
121 #include <sys/resource.h>
122 
123 #include <netinet/in.h>
124 #include <netinet/in_systm.h>
125 #include <netinet/ip.h>
126 
127 #define	FTP_NAMES
128 #include <arpa/ftp.h>
129 #include <arpa/inet.h>
130 #include <arpa/telnet.h>
131 
132 #include <ctype.h>
133 #include <dirent.h>
134 #include <err.h>
135 #include <errno.h>
136 #include <fcntl.h>
137 #include <fnmatch.h>
138 #include <glob.h>
139 #include <grp.h>
140 #include <limits.h>
141 #include <netdb.h>
142 #include <pwd.h>
143 #include <poll.h>
144 #include <signal.h>
145 #include <stdarg.h>
146 #include <stdio.h>
147 #include <stdlib.h>
148 #include <string.h>
149 #include <syslog.h>
150 #include <time.h>
151 #include <tzfile.h>
152 #include <unistd.h>
153 #include <util.h>
154 #ifdef SUPPORT_UTMP
155 #include <utmp.h>
156 #endif
157 #ifdef SUPPORT_UTMPX
158 #include <utmpx.h>
159 #endif
160 #ifdef SKEY
161 #include <skey.h>
162 #endif
163 #ifdef KERBEROS5
164 #include <com_err.h>
165 #include <krb5/krb5.h>
166 #endif
167 
168 #ifdef	LOGIN_CAP
169 #include <login_cap.h>
170 #endif
171 
172 #ifdef USE_PAM
173 #include <security/pam_appl.h>
174 #endif
175 
176 #define	GLOBAL
177 #include "extern.h"
178 #include "pathnames.h"
179 #include "version.h"
180 
181 static sig_atomic_t	transflag;
182 static sig_atomic_t	urgflag;
183 
184 int	data;
185 int	Dflag;
186 int	sflag;
187 int	stru;			/* avoid C keyword */
188 int	mode;
189 int	dataport;		/* use specific data port */
190 int	dopidfile;		/* maintain pid file */
191 int	doutmp;			/* update utmp file */
192 int	dowtmp;			/* update wtmp file */
193 int	doxferlog;		/* syslog/write wu-ftpd style xferlog entries */
194 int	xferlogfd;		/* fd to write wu-ftpd xferlog entries to */
195 int	getnameopts;		/* flags for use with getname() */
196 int	dropprivs;		/* if privileges should or have been dropped */
197 int	mapped;			/* IPv4 connection on AF_INET6 socket */
198 off_t	file_size;
199 off_t	byte_count;
200 static char ttyline[20];
201 
202 #ifdef USE_PAM
203 static int	auth_pam(void);
204 pam_handle_t	*pamh = NULL;
205 #endif
206 
207 #ifdef SUPPORT_UTMP
208 static struct utmp utmp;	/* for utmp */
209 #endif
210 #ifdef SUPPORT_UTMPX
211 static struct utmpx utmpx;	/* for utmpx */
212 #endif
213 
214 static const char *anondir = NULL;
215 static const char *confdir = _DEFAULT_CONFDIR;
216 
217 static char	*curname;		/* current USER name */
218 static size_t	curname_len;		/* length of curname (include NUL) */
219 
220 #if defined(KERBEROS) || defined(KERBEROS5)
221 int	has_ccache = 0;
222 int	notickets = 1;
223 char	*krbtkfile_env = NULL;
224 char	*tty = ttyline;
225 int	login_krb5_forwardable_tgt = 0;
226 #endif
227 
228 int epsvall = 0;
229 
230 /*
231  * Timeout intervals for retrying connections
232  * to hosts that don't accept PORT cmds.  This
233  * is a kludge, but given the problems with TCP...
234  */
235 #define	SWAITMAX	90	/* wait at most 90 seconds */
236 #define	SWAITINT	5	/* interval between retries */
237 
238 int	swaitmax = SWAITMAX;
239 int	swaitint = SWAITINT;
240 
241 enum send_status {
242 	SS_SUCCESS,
243 	SS_ABORTED,			/* transfer aborted */
244 	SS_NO_TRANSFER,			/* no transfer made yet */
245 	SS_FILE_ERROR,			/* file read error */
246 	SS_DATA_ERROR			/* data send error */
247 };
248 
249 static int	 bind_pasv_addr(void);
250 static int	 checkuser(const char *, const char *, int, int, char **);
251 static int	 checkaccess(const char *);
252 static int	 checkpassword(const struct passwd *, const char *);
253 static void	 do_pass(int, int, const char *);
254 static void	 end_login(void);
255 static FILE	*getdatasock(const char *);
256 static char	*gunique(const char *);
257 static void	 login_utmp(const char *, const char *, const char *,
258 		     struct sockinet *);
259 static void	 logremotehost(struct sockinet *);
260 static void	 lostconn(int);
261 static void	 toolong(int);
262 static void	 sigquit(int);
263 static void	 sigurg(int);
264 static int	 handleoobcmd(void);
265 static int	 receive_data(FILE *, FILE *);
266 static int	 send_data(FILE *, FILE *, const struct stat *, int);
267 static struct passwd *sgetpwnam(const char *);
268 static int	 write_data(int, char *, size_t, off_t *, struct timeval *,
269 		     int);
270 static enum send_status
271 		 send_data_with_read(int, int, const struct stat *, int);
272 static enum send_status
273 		 send_data_with_mmap(int, int, const struct stat *, int);
274 static void	 logrusage(const struct rusage *, const struct rusage *);
275 static void	 logout_utmp(void);
276 
277 int	main(int, char *[]);
278 
279 #if defined(KERBEROS)
280 int	klogin(struct passwd *, char *, char *, char *);
281 void	kdestroy(void);
282 #endif
283 #if defined(KERBEROS5)
284 int	k5login(struct passwd *, char *, char *, char *);
285 void	k5destroy(void);
286 #endif
287 
288 int
289 main(int argc, char *argv[])
290 {
291 	int		ch, on = 1, tos, keepalive;
292 	socklen_t	addrlen;
293 #ifdef KERBEROS5
294 	krb5_error_code	kerror;
295 #endif
296 	char		*p;
297 	const char	*xferlogname = NULL;
298 	long		l;
299 	struct sigaction sa;
300 	sa_family_t	af = AF_UNSPEC;
301 
302 	connections = 1;
303 	ftpd_debug = 0;
304 	logging = 0;
305 	pdata = -1;
306 	Dflag = 0;
307 	sflag = 0;
308 	dataport = 0;
309 	dopidfile = 1;		/* default: DO use a pid file to count users */
310 	doutmp = 0;		/* default: Do NOT log to utmp */
311 	dowtmp = 1;		/* default: DO log to wtmp */
312 	doxferlog = 0;		/* default: Do NOT syslog xferlog */
313 	xferlogfd = -1;		/* default: Do NOT write xferlog file */
314 	getnameopts = 0;	/* default: xlate addrs to name */
315 	dropprivs = 0;
316 	mapped = 0;
317 	usedefault = 1;
318 	emailaddr = NULL;
319 	hostname[0] = '\0';
320 	homedir[0] = '\0';
321 	gidcount = 0;
322 	is_oob = 0;
323 	version = FTPD_VERSION;
324 
325 	/*
326 	 * LOG_NDELAY sets up the logging connection immediately,
327 	 * necessary for anonymous ftp's that chroot and can't do it later.
328 	 */
329 	openlog("ftpd", LOG_PID | LOG_NDELAY, LOG_FTP);
330 
331 	while ((ch = getopt(argc, argv,
332 	    "46a:c:C:Dde:h:HlL:nP:qQrst:T:uUvV:wWX")) != -1) {
333 		switch (ch) {
334 		case '4':
335 			af = AF_INET;
336 			break;
337 
338 		case '6':
339 			af = AF_INET6;
340 			break;
341 
342 		case 'a':
343 			anondir = optarg;
344 			break;
345 
346 		case 'c':
347 			confdir = optarg;
348 			break;
349 
350 		case 'C':
351 			pw = sgetpwnam(optarg);
352 			exit(checkaccess(optarg) ? 0 : 1);
353 			/* NOTREACHED */
354 
355 		case 'D':
356 			Dflag = 1;
357 			break;
358 
359 		case 'd':
360 		case 'v':		/* deprecated */
361 			ftpd_debug = 1;
362 			break;
363 
364 		case 'e':
365 			emailaddr = optarg;
366 			break;
367 
368 		case 'h':
369 			strlcpy(hostname, optarg, sizeof(hostname));
370 			break;
371 
372 		case 'H':
373 			if (gethostname(hostname, sizeof(hostname)) == -1)
374 				hostname[0] = '\0';
375 			hostname[sizeof(hostname) - 1] = '\0';
376 			break;
377 
378 		case 'l':
379 			logging++;	/* > 1 == extra logging */
380 			break;
381 
382 		case 'L':
383 			xferlogname = optarg;
384 			break;
385 
386 		case 'n':
387 			getnameopts = NI_NUMERICHOST;
388 			break;
389 
390 		case 'P':
391 			errno = 0;
392 			p = NULL;
393 			l = strtol(optarg, &p, 10);
394 			if (errno || *optarg == '\0' || *p != '\0' ||
395 			    l < IPPORT_RESERVED ||
396 			    l > IPPORT_ANONMAX) {
397 				syslog(LOG_WARNING, "Invalid dataport %s",
398 				    optarg);
399 				dataport = 0;
400 			}
401 			dataport = (int)l;
402 			break;
403 
404 		case 'q':
405 			dopidfile = 1;
406 			break;
407 
408 		case 'Q':
409 			dopidfile = 0;
410 			break;
411 
412 		case 'r':
413 			dropprivs = 1;
414 			break;
415 
416 		case 's':
417 			sflag = 1;
418 			break;
419 
420 		case 't':
421 		case 'T':
422 			syslog(LOG_WARNING,
423 			    "-%c has been deprecated in favour of ftpd.conf",
424 			    ch);
425 			break;
426 
427 		case 'u':
428 			doutmp = 1;
429 			break;
430 
431 		case 'U':
432 			doutmp = 0;
433 			break;
434 
435 		case 'V':
436 			if (EMPTYSTR(optarg) || strcmp(optarg, "-") == 0)
437 				version = NULL;
438 			else
439 				version = ftpd_strdup(optarg);
440 			break;
441 
442 		case 'w':
443 			dowtmp = 1;
444 			break;
445 
446 		case 'W':
447 			dowtmp = 0;
448 			break;
449 
450 		case 'X':
451 			doxferlog |= 1;
452 			break;
453 
454 		default:
455 			if (optopt == 'a' || optopt == 'C')
456 				exit(1);
457 			syslog(LOG_WARNING, "unknown flag -%c ignored", optopt);
458 			break;
459 		}
460 	}
461 	if (EMPTYSTR(confdir))
462 		confdir = _DEFAULT_CONFDIR;
463 
464 	if (dowtmp) {
465 #ifdef SUPPORT_UTMPX
466 		ftpd_initwtmpx();
467 #endif
468 #ifdef SUPPORT_UTMP
469 		ftpd_initwtmp();
470 #endif
471 	}
472 	errno = 0;
473 	l = sysconf(_SC_LOGIN_NAME_MAX);
474 	if (l == -1 && errno != 0) {
475 		syslog(LOG_ERR, "sysconf _SC_LOGIN_NAME_MAX: %m");
476 		exit(1);
477 	} else if (l <= 0) {
478 		syslog(LOG_WARNING, "using conservative LOGIN_NAME_MAX value");
479 		curname_len = _POSIX_LOGIN_NAME_MAX;
480 	} else
481 		curname_len = (size_t)l;
482 	curname = malloc(curname_len);
483 	if (curname == NULL) {
484 		syslog(LOG_ERR, "malloc: %m");
485 		exit(1);
486 	}
487 	curname[0] = '\0';
488 
489 	if (Dflag) {
490 		int error, fd, i, n, *socks;
491 		struct pollfd *fds;
492 		struct addrinfo hints, *res, *res0;
493 
494 		if (daemon(1, 0) == -1) {
495 			syslog(LOG_ERR, "failed to daemonize: %m");
496 			exit(1);
497 		}
498 		(void)memset(&sa, 0, sizeof(sa));
499 		sa.sa_handler = SIG_IGN;
500 		sa.sa_flags = SA_NOCLDWAIT;
501 		sigemptyset(&sa.sa_mask);
502 		(void)sigaction(SIGCHLD, &sa, NULL);
503 
504 		(void)memset(&hints, 0, sizeof(hints));
505 		hints.ai_flags = AI_PASSIVE;
506 		hints.ai_family = af;
507 		hints.ai_socktype = SOCK_STREAM;
508 		error = getaddrinfo(NULL, "ftp", &hints, &res0);
509 		if (error) {
510 			syslog(LOG_ERR, "getaddrinfo: %s", gai_strerror(error));
511 			exit(1);
512 		}
513 
514 		for (n = 0, res = res0; res != NULL; res = res->ai_next)
515 			n++;
516 		if (n == 0) {
517 			syslog(LOG_ERR, "no addresses available");
518 			exit(1);
519 		}
520 		socks = malloc(n * sizeof(int));
521 		fds = malloc(n * sizeof(struct pollfd));
522 		if (socks == NULL || fds == NULL) {
523 			syslog(LOG_ERR, "malloc: %m");
524 			exit(1);
525 		}
526 
527 		for (n = 0, res = res0; res != NULL; res = res->ai_next) {
528 			socks[n] = socket(res->ai_family, res->ai_socktype,
529 			    res->ai_protocol);
530 			if (socks[n] == -1)
531 				continue;
532 			(void)setsockopt(socks[n], SOL_SOCKET, SO_REUSEADDR,
533 			    &on, sizeof(on));
534 			if (bind(socks[n], res->ai_addr, res->ai_addrlen)
535 			    == -1) {
536 				(void)close(socks[n]);
537 				continue;
538 			}
539 			if (listen(socks[n], 12) == -1) {
540 				(void)close(socks[n]);
541 				continue;
542 			}
543 
544 			fds[n].fd = socks[n];
545 			fds[n].events = POLLIN;
546 			n++;
547 		}
548 		if (n == 0) {
549 			syslog(LOG_ERR, "%m");
550 			exit(1);
551 		}
552 		freeaddrinfo(res0);
553 
554 		if (pidfile(NULL) == -1)
555 			syslog(LOG_ERR, "failed to write a pid file: %m");
556 
557 		for (;;) {
558 			if (poll(fds, n, INFTIM) == -1) {
559 				if (errno == EINTR)
560 					continue;
561 				syslog(LOG_ERR, "poll: %m");
562 				exit(1);
563 			}
564 			for (i = 0; i < n; i++) {
565 				if (fds[i].revents & POLLIN) {
566 					fd = accept(fds[i].fd, NULL, NULL);
567 					if (fd == -1) {
568 						syslog(LOG_ERR, "accept: %m");
569 						continue;
570 					}
571 					switch (fork()) {
572 					case -1:
573 						syslog(LOG_ERR, "fork: %m");
574 						break;
575 					case 0:
576 						goto child;
577 						/* NOTREACHED */
578 					}
579 					(void)close(fd);
580 				}
581 			}
582 		}
583  child:
584 		(void)dup2(fd, STDIN_FILENO);
585 		(void)dup2(fd, STDOUT_FILENO);
586 		(void)dup2(fd, STDERR_FILENO);
587 		for (i = 0; i < n; i++)
588 			(void)close(socks[i]);
589 	}
590 
591 	memset((char *)&his_addr, 0, sizeof(his_addr));
592 	addrlen = sizeof(his_addr.si_su);
593 	if (getpeername(0, (struct sockaddr *)&his_addr.si_su, &addrlen) < 0) {
594 		syslog(LOG_ERR, "getpeername (%s): %m",argv[0]);
595 		exit(1);
596 	}
597 	his_addr.su_len = addrlen;
598 	memset((char *)&ctrl_addr, 0, sizeof(ctrl_addr));
599 	addrlen = sizeof(ctrl_addr.si_su);
600 	if (getsockname(0, (struct sockaddr *)&ctrl_addr, &addrlen) < 0) {
601 		syslog(LOG_ERR, "getsockname (%s): %m",argv[0]);
602 		exit(1);
603 	}
604 	ctrl_addr.su_len = addrlen;
605 #ifdef INET6
606 	if (his_addr.su_family == AF_INET6
607 	 && IN6_IS_ADDR_V4MAPPED(&his_addr.su_6addr)) {
608 #if 1
609 		/*
610 		 * IPv4 control connection arrived to AF_INET6 socket.
611 		 * I hate to do this, but this is the easiest solution.
612 		 *
613 		 * The assumption is untrue on SIIT environment.
614 		 */
615 		struct sockinet tmp_addr;
616 		const int off = sizeof(struct in6_addr) - sizeof(struct in_addr);
617 
618 		tmp_addr = his_addr;
619 		memset(&his_addr, 0, sizeof(his_addr));
620 		his_addr.su_family = AF_INET;
621 		his_addr.su_len = sizeof(his_addr.si_su.su_sin);
622 		memcpy(&his_addr.su_addr, &tmp_addr.su_6addr.s6_addr[off],
623 		    sizeof(his_addr.su_addr));
624 		his_addr.su_port = tmp_addr.su_port;
625 
626 		tmp_addr = ctrl_addr;
627 		memset(&ctrl_addr, 0, sizeof(ctrl_addr));
628 		ctrl_addr.su_family = AF_INET;
629 		ctrl_addr.su_len = sizeof(ctrl_addr.si_su.su_sin);
630 		memcpy(&ctrl_addr.su_addr, &tmp_addr.su_6addr.s6_addr[off],
631 		    sizeof(ctrl_addr.su_addr));
632 		ctrl_addr.su_port = tmp_addr.su_port;
633 #else
634 		while (fgets(line, sizeof(line), fd) != NULL) {
635 			if ((cp = strchr(line, '\n')) != NULL)
636 				*cp = '\0';
637 			reply(-530, "%s", line);
638 		}
639 		(void) fflush(stdout);
640 		(void) fclose(fd);
641 		reply(530,
642 		    "Connection from IPv4 mapped address is not supported.");
643 		exit(0);
644 #endif
645 
646 		mapped = 1;
647 	} else
648 #endif /* INET6 */
649 		mapped = 0;
650 #ifdef IP_TOS
651 	if (!mapped && his_addr.su_family == AF_INET) {
652 		tos = IPTOS_LOWDELAY;
653 		if (setsockopt(0, IPPROTO_IP, IP_TOS, (char *)&tos,
654 			       sizeof(int)) < 0)
655 			syslog(LOG_WARNING, "setsockopt (IP_TOS): %m");
656 	}
657 #endif
658 	/* if the hostname hasn't been given, attempt to determine it */
659 	if (hostname[0] == '\0') {
660 		if (getnameinfo((struct sockaddr *)&ctrl_addr.si_su,
661 		    ctrl_addr.su_len, hostname, sizeof(hostname), NULL, 0,
662 			getnameopts) != 0)
663 			(void)gethostname(hostname, sizeof(hostname));
664 		hostname[sizeof(hostname) - 1] = '\0';
665 	}
666 
667 	/* set this here so klogin can use it... */
668 	(void)snprintf(ttyline, sizeof(ttyline), "ftp%d", getpid());
669 
670 	(void) freopen(_PATH_DEVNULL, "w", stderr);
671 
672 	memset(&sa, 0, sizeof(sa));
673 	sa.sa_handler = SIG_DFL;
674 	sa.sa_flags = SA_RESTART;
675 	sigemptyset(&sa.sa_mask);
676 	(void) sigaction(SIGCHLD, &sa, NULL);
677 
678 	sa.sa_handler = sigquit;
679 	sa.sa_flags = SA_RESTART;
680 	sigfillset(&sa.sa_mask);	/* block all sigs in these handlers */
681 	(void) sigaction(SIGHUP, &sa, NULL);
682 	(void) sigaction(SIGINT, &sa, NULL);
683 	(void) sigaction(SIGQUIT, &sa, NULL);
684 	(void) sigaction(SIGTERM, &sa, NULL);
685 	sa.sa_handler = lostconn;
686 	(void) sigaction(SIGPIPE, &sa, NULL);
687 	sa.sa_handler = toolong;
688 	(void) sigaction(SIGALRM, &sa, NULL);
689 	sa.sa_handler = sigurg;
690 	(void) sigaction(SIGURG, &sa, NULL);
691 
692 	/* Try to handle urgent data inline */
693 #ifdef SO_OOBINLINE
694 	if (setsockopt(0, SOL_SOCKET, SO_OOBINLINE, (char *)&on, sizeof(on)) < 0)
695 		syslog(LOG_WARNING, "setsockopt: %m");
696 #endif
697 	/* Set keepalives on the socket to detect dropped connections.  */
698 #ifdef SO_KEEPALIVE
699 	keepalive = 1;
700 	if (setsockopt(0, SOL_SOCKET, SO_KEEPALIVE, (char *)&keepalive,
701 	    sizeof(int)) < 0)
702 		syslog(LOG_WARNING, "setsockopt (SO_KEEPALIVE): %m");
703 #endif
704 
705 #ifdef	F_SETOWN
706 	if (fcntl(fileno(stdin), F_SETOWN, getpid()) == -1)
707 		syslog(LOG_WARNING, "fcntl F_SETOWN: %m");
708 #endif
709 	logremotehost(&his_addr);
710 	/*
711 	 * Set up default state
712 	 */
713 	data = -1;
714 	type = TYPE_A;
715 	form = FORM_N;
716 	stru = STRU_F;
717 	mode = MODE_S;
718 	tmpline[0] = '\0';
719 	hasyyerrored = 0;
720 
721 #ifdef KERBEROS5
722 	kerror = krb5_init_context(&kcontext);
723 	if (kerror) {
724 		syslog(LOG_ERR, "%s when initializing Kerberos context",
725 		    error_message(kerror));
726 		exit(0);
727 	}
728 #endif /* KERBEROS5 */
729 
730 	init_curclass();
731 	curclass.timeout = 300;		/* 5 minutes, as per login(1) */
732 	curclass.type = CLASS_REAL;
733 
734 	/* If logins are disabled, print out the message. */
735 	if (display_file(_PATH_NOLOGIN, 530)) {
736 		reply(530, "System not available.");
737 		exit(0);
738 	}
739 	(void)display_file(conffilename(_NAME_FTPWELCOME), 220);
740 		/* reply(220,) must follow */
741 	if (EMPTYSTR(version))
742 		reply(220, "%s FTP server ready.", hostname);
743 	else
744 		reply(220, "%s FTP server (%s) ready.", hostname, version);
745 
746 	if (xferlogname != NULL) {
747 		xferlogfd = open(xferlogname, O_WRONLY | O_APPEND | O_CREAT,
748 		    0660);
749 		if (xferlogfd == -1)
750 			syslog(LOG_WARNING, "open xferlog `%s': %m",
751 			    xferlogname);
752 		else
753 			doxferlog |= 2;
754 	}
755 
756 	ftp_loop();
757 	/* NOTREACHED */
758 }
759 
760 static void
761 lostconn(int signo __unused)
762 {
763 
764 	if (ftpd_debug)
765 		syslog(LOG_DEBUG, "lost connection");
766 	dologout(1);
767 }
768 
769 static void
770 toolong(int signo __unused)
771 {
772 
773 		/* XXXSIGRACE */
774 	reply(421,
775 	    "Timeout (" LLF " seconds): closing control connection.",
776 	    (LLT)curclass.timeout);
777 	if (logging)
778 		syslog(LOG_INFO, "User %s timed out after " LLF " seconds",
779 		    (pw ? pw->pw_name : "unknown"), (LLT)curclass.timeout);
780 	dologout(1);
781 }
782 
783 static void
784 sigquit(int signo)
785 {
786 
787 	if (ftpd_debug)
788 		syslog(LOG_DEBUG, "got signal %d", signo);
789 	dologout(1);
790 }
791 
792 static void
793 sigurg(int signo __unused)
794 {
795 
796 	urgflag = 1;
797 }
798 
799 
800 /*
801  * Save the result of a getpwnam.  Used for USER command, since
802  * the data returned must not be clobbered by any other command
803  * (e.g., globbing).
804  */
805 static struct passwd *
806 sgetpwnam(const char *name)
807 {
808 	static struct passwd save;
809 	struct passwd *p;
810 
811 	if ((p = getpwnam(name)) == NULL)
812 		return (p);
813 	if (save.pw_name) {
814 		free((char *)save.pw_name);
815 		memset(save.pw_passwd, 0, strlen(save.pw_passwd));
816 		free((char *)save.pw_passwd);
817 		free((char *)save.pw_gecos);
818 		free((char *)save.pw_dir);
819 		free((char *)save.pw_shell);
820 	}
821 	save = *p;
822 	save.pw_name = ftpd_strdup(p->pw_name);
823 	save.pw_passwd = ftpd_strdup(p->pw_passwd);
824 	save.pw_gecos = ftpd_strdup(p->pw_gecos);
825 	save.pw_dir = ftpd_strdup(p->pw_dir);
826 	save.pw_shell = ftpd_strdup(p->pw_shell);
827 	return (&save);
828 }
829 
830 static int	login_attempts;	/* number of failed login attempts */
831 static int	askpasswd;	/* had USER command, ask for PASSwd */
832 static int	permitted;	/* USER permitted */
833 
834 /*
835  * USER command.
836  * Sets global passwd pointer pw if named account exists and is acceptable;
837  * sets askpasswd if a PASS command is expected.  If logged in previously,
838  * need to reset state.  If name is "ftp" or "anonymous", the name is not in
839  * _NAME_FTPUSERS, and ftp account exists, set guest and pw, then just return.
840  * If account doesn't exist, ask for passwd anyway.  Otherwise, check user
841  * requesting login privileges.  Disallow anyone who does not have a standard
842  * shell as returned by getusershell().  Disallow anyone mentioned in the file
843  * _NAME_FTPUSERS to allow people such as root and uucp to be avoided.
844  */
845 void
846 user(const char *name)
847 {
848 	char	*class;
849 #ifdef	LOGIN_CAP
850 	login_cap_t *lc = NULL;
851 #endif
852 #ifdef USE_PAM
853 	int e;
854 #endif
855 
856 	class = NULL;
857 	if (logged_in) {
858 		switch (curclass.type) {
859 		case CLASS_GUEST:
860 			reply(530, "Can't change user from guest login.");
861 			return;
862 		case CLASS_CHROOT:
863 			reply(530, "Can't change user from chroot user.");
864 			return;
865 		case CLASS_REAL:
866 			if (dropprivs) {
867 				reply(530, "Can't change user.");
868 				return;
869 			}
870 			end_login();
871 			break;
872 		default:
873 			abort();
874 		}
875 	}
876 
877 #if defined(KERBEROS)
878 	kdestroy();
879 #endif
880 #if defined(KERBEROS5)
881 	k5destroy();
882 #endif
883 
884 	curclass.type = CLASS_REAL;
885 	askpasswd = 0;
886 	permitted = 0;
887 
888 	if (strcmp(name, "ftp") == 0 || strcmp(name, "anonymous") == 0) {
889 			/* need `pw' setup for checkaccess() and checkuser () */
890 		if ((pw = sgetpwnam("ftp")) == NULL)
891 			reply(530, "User %s unknown.", name);
892 		else if (! checkaccess("ftp") || ! checkaccess("anonymous"))
893 			reply(530, "User %s access denied.", name);
894 		else {
895 			curclass.type = CLASS_GUEST;
896 			askpasswd = 1;
897 			reply(331,
898 			    "Guest login ok, type your name as password.");
899 		}
900 		if (!askpasswd) {
901 			if (logging)
902 				syslog(LOG_NOTICE,
903 				    "ANONYMOUS FTP LOGIN REFUSED FROM %s",
904 				    remotehost);
905 			end_login();
906 			goto cleanup_user;
907 		}
908 		name = "ftp";
909 	} else
910 		pw = sgetpwnam(name);
911 
912 	strlcpy(curname, name, curname_len);
913 
914 			/* check user in /etc/ftpusers, and setup class */
915 	permitted = checkuser(_NAME_FTPUSERS, curname, 1, 0, &class);
916 
917 			/* check user in /etc/ftpchroot */
918 #ifdef	LOGIN_CAP
919 	lc = login_getpwclass(pw);
920 #endif
921 	if (checkuser(_NAME_FTPCHROOT, curname, 0, 0, NULL)
922 #ifdef	LOGIN_CAP	/* Allow login.conf configuration as well */
923 	    || login_getcapbool(lc, "ftp-chroot", 0)
924 #endif
925 	) {
926 		if (curclass.type == CLASS_GUEST) {
927 			syslog(LOG_NOTICE,
928 	    "Can't change guest user to chroot class; remove entry in %s",
929 			    _NAME_FTPCHROOT);
930 			exit(1);
931 		}
932 		curclass.type = CLASS_CHROOT;
933 	}
934 
935 			/* determine default class */
936 	if (class == NULL) {
937 		switch (curclass.type) {
938 		case CLASS_GUEST:
939 			class = ftpd_strdup("guest");
940 			break;
941 		case CLASS_CHROOT:
942 			class = ftpd_strdup("chroot");
943 			break;
944 		case CLASS_REAL:
945 			class = ftpd_strdup("real");
946 			break;
947 		default:
948 			syslog(LOG_ERR, "unknown curclass.type %d; aborting",
949 			    curclass.type);
950 			abort();
951 		}
952 	}
953 			/* parse ftpd.conf, setting up various parameters */
954 	parse_conf(class);
955 			/* if not guest user, check for valid shell */
956 	if (pw == NULL)
957 		permitted = 0;
958 	else {
959 		const char	*cp, *shell;
960 
961 		if ((shell = pw->pw_shell) == NULL || *shell == 0)
962 			shell = _PATH_BSHELL;
963 		while ((cp = getusershell()) != NULL)
964 			if (strcmp(cp, shell) == 0)
965 				break;
966 		endusershell();
967 		if (cp == NULL && curclass.type != CLASS_GUEST)
968 			permitted = 0;
969 	}
970 
971 			/* deny quickly (after USER not PASS) if requested */
972 	if (CURCLASS_FLAGS_ISSET(denyquick) && !permitted) {
973 		reply(530, "User %s may not use FTP.", curname);
974 		if (logging)
975 			syslog(LOG_NOTICE, "FTP LOGIN REFUSED FROM %s, %s",
976 			    remotehost, curname);
977 		end_login();
978 		goto cleanup_user;
979 	}
980 
981 			/* if haven't asked yet (i.e, not anon), ask now */
982 	if (!askpasswd) {
983 		askpasswd = 1;
984 #ifdef USE_PAM
985 		e = auth_pam();		/* this does reply(331, ...) */
986 		do_pass(1, e, "");
987 		goto cleanup_user;
988 #else /* !USE_PAM */
989 #ifdef SKEY
990 		if (skey_haskey(curname) == 0) {
991 			const char *myskey;
992 
993 			myskey = skey_keyinfo(curname);
994 			reply(331, "Password [ %s ] required for %s.",
995 			    myskey ? myskey : "error getting challenge",
996 			    curname);
997 		} else
998 #endif
999 			reply(331, "Password required for %s.", curname);
1000 #endif /* !USE_PAM */
1001 	}
1002 
1003  cleanup_user:
1004 #ifdef LOGIN_CAP
1005 	login_close(lc);
1006 #endif
1007 	/*
1008 	 * Delay before reading passwd after first failed
1009 	 * attempt to slow down passwd-guessing programs.
1010 	 */
1011 	if (login_attempts)
1012 		sleep((unsigned) login_attempts);
1013 
1014 	if (class)
1015 		free(class);
1016 }
1017 
1018 /*
1019  * Determine whether something is to happen (allow access, chroot)
1020  * for a user. Each line is a shell-style glob followed by
1021  * `yes' or `no'.
1022  *
1023  * For backward compatibility, `allow' and `deny' are synonymns
1024  * for `yes' and `no', respectively.
1025  *
1026  * Each glob is matched against the username in turn, and the first
1027  * match found is used. If no match is found, the result is the
1028  * argument `def'. If a match is found but without and explicit
1029  * `yes'/`no', the result is the opposite of def.
1030  *
1031  * If the file doesn't exist at all, the result is the argument
1032  * `nofile'
1033  *
1034  * Any line starting with `#' is considered a comment and ignored.
1035  *
1036  * Returns 0 if the user is denied, or 1 if they are allowed.
1037  *
1038  * NOTE: needs struct passwd *pw setup before use.
1039  */
1040 static int
1041 checkuser(const char *fname, const char *name, int def, int nofile,
1042 	    char **retclass)
1043 {
1044 	FILE	*fd;
1045 	int	 retval;
1046 	char	*word, *perm, *class, *buf, *p;
1047 	size_t	 len, line;
1048 
1049 	retval = def;
1050 	if (retclass != NULL)
1051 		*retclass = NULL;
1052 	if ((fd = fopen(conffilename(fname), "r")) == NULL)
1053 		return nofile;
1054 
1055 	line = 0;
1056 	for (;
1057 	    (buf = fparseln(fd, &len, &line, NULL, FPARSELN_UNESCCOMM |
1058 			    FPARSELN_UNESCCONT | FPARSELN_UNESCESC)) != NULL;
1059 	    free(buf), buf = NULL) {
1060 		word = perm = class = NULL;
1061 		p = buf;
1062 		if (len < 1)
1063 			continue;
1064 		if (p[len - 1] == '\n')
1065 			p[--len] = '\0';
1066 		if (EMPTYSTR(p))
1067 			continue;
1068 
1069 		NEXTWORD(p, word);
1070 		NEXTWORD(p, perm);
1071 		NEXTWORD(p, class);
1072 		if (EMPTYSTR(word))
1073 			continue;
1074 		if (!EMPTYSTR(class)) {
1075 			if (strcasecmp(class, "all") == 0 ||
1076 			    strcasecmp(class, "none") == 0) {
1077 				syslog(LOG_WARNING,
1078 		"%s line %d: illegal user-defined class `%s' - skipping entry",
1079 					    fname, (int)line, class);
1080 				continue;
1081 			}
1082 		}
1083 
1084 					/* have a host specifier */
1085 		if ((p = strchr(word, '@')) != NULL) {
1086 			unsigned long	net, mask, addr;
1087 			int		bits;
1088 
1089 			*p++ = '\0';
1090 					/* check against network or CIDR */
1091 			if (isdigit((unsigned char)*p) &&
1092 			    (bits = inet_net_pton(AF_INET, p,
1093 			    &net, sizeof(net))) != -1) {
1094 				net = ntohl(net);
1095 				mask = 0xffffffffU << (32 - bits);
1096 				addr = ntohl(his_addr.su_addr.s_addr);
1097 				if ((addr & mask) != net)
1098 					continue;
1099 
1100 					/* check against hostname glob */
1101 			} else if (fnmatch(p, remotehost, FNM_CASEFOLD) != 0)
1102 				continue;
1103 		}
1104 
1105 					/* have a group specifier */
1106 		if ((p = strchr(word, ':')) != NULL) {
1107 			gid_t	*groups, *ng;
1108 			int	 gsize, i, found;
1109 
1110 			if (pw == NULL)
1111 				continue;	/* no match for unknown user */
1112 			*p++ = '\0';
1113 			groups = NULL;
1114 			gsize = 16;
1115 			do {
1116 				ng = realloc(groups, gsize * sizeof(gid_t));
1117 				if (ng == NULL)
1118 					fatal(
1119 					    "Local resource failure: realloc");
1120 				groups = ng;
1121 			} while (getgrouplist(pw->pw_name, pw->pw_gid,
1122 						groups, &gsize) == -1);
1123 			found = 0;
1124 			for (i = 0; i < gsize; i++) {
1125 				struct group *g;
1126 
1127 				if ((g = getgrgid(groups[i])) == NULL)
1128 					continue;
1129 				if (fnmatch(p, g->gr_name, 0) == 0) {
1130 					found = 1;
1131 					break;
1132 				}
1133 			}
1134 			free(groups);
1135 			if (!found)
1136 				continue;
1137 		}
1138 
1139 					/* check against username glob */
1140 		if (fnmatch(word, name, 0) != 0)
1141 			continue;
1142 
1143 		if (perm != NULL &&
1144 		    ((strcasecmp(perm, "allow") == 0) ||
1145 		     (strcasecmp(perm, "yes") == 0)))
1146 			retval = 1;
1147 		else if (perm != NULL &&
1148 		    ((strcasecmp(perm, "deny") == 0) ||
1149 		     (strcasecmp(perm, "no") == 0)))
1150 			retval = 0;
1151 		else
1152 			retval = !def;
1153 		if (!EMPTYSTR(class) && retclass != NULL)
1154 			*retclass = ftpd_strdup(class);
1155 		free(buf);
1156 		break;
1157 	}
1158 	(void) fclose(fd);
1159 	return (retval);
1160 }
1161 
1162 /*
1163  * Check if user is allowed by /etc/ftpusers
1164  * returns 1 for yes, 0 for no
1165  *
1166  * NOTE: needs struct passwd *pw setup (for checkuser())
1167  */
1168 static int
1169 checkaccess(const char *name)
1170 {
1171 
1172 	return (checkuser(_NAME_FTPUSERS, name, 1, 0, NULL));
1173 }
1174 
1175 static void
1176 login_utmp(const char *line, const char *name, const char *host,
1177     struct sockinet *haddr)
1178 {
1179 #if defined(SUPPORT_UTMPX) || defined(SUPPORT_UTMP)
1180 	struct timeval tv;
1181 	(void)gettimeofday(&tv, NULL);
1182 #endif
1183 #ifdef SUPPORT_UTMPX
1184 	if (doutmp) {
1185 		(void)memset(&utmpx, 0, sizeof(utmpx));
1186 		utmpx.ut_tv = tv;
1187 		utmpx.ut_pid = getpid();
1188 		utmpx.ut_id[0] = 'f';
1189 		utmpx.ut_id[1] = 't';
1190 		utmpx.ut_id[2] = 'p';
1191 		utmpx.ut_id[3] = '*';
1192 		utmpx.ut_type = USER_PROCESS;
1193 		(void)strncpy(utmpx.ut_name, name, sizeof(utmpx.ut_name));
1194 		(void)strncpy(utmpx.ut_line, line, sizeof(utmpx.ut_line));
1195 		(void)strncpy(utmpx.ut_host, host, sizeof(utmpx.ut_host));
1196 		(void)memcpy(&utmpx.ut_ss, &haddr->si_su, haddr->su_len);
1197 		ftpd_loginx(&utmpx);
1198 	}
1199 	if (dowtmp)
1200 		ftpd_logwtmpx(line, name, host, haddr, 0, USER_PROCESS);
1201 #endif
1202 #ifdef SUPPORT_UTMP
1203 	if (doutmp) {
1204 		(void)memset(&utmp, 0, sizeof(utmp));
1205 		(void)time(&utmp.ut_time);
1206 		(void)strncpy(utmp.ut_name, name, sizeof(utmp.ut_name));
1207 		(void)strncpy(utmp.ut_line, line, sizeof(utmp.ut_line));
1208 		(void)strncpy(utmp.ut_host, host, sizeof(utmp.ut_host));
1209 		ftpd_login(&utmp);
1210 	}
1211 	if (dowtmp)
1212 		ftpd_logwtmp(line, name, host);
1213 #endif
1214 }
1215 
1216 static void
1217 logout_utmp(void)
1218 {
1219 #ifdef SUPPORT_UTMPX
1220 	int okwtmpx = dowtmp;
1221 #endif
1222 #ifdef SUPPORT_UTMP
1223 	int okwtmp = dowtmp;
1224 #endif
1225 	if (logged_in) {
1226 #ifdef SUPPORT_UTMPX
1227 		if (doutmp)
1228 			okwtmpx &= ftpd_logoutx(ttyline, 0, DEAD_PROCESS);
1229 		if (okwtmpx)
1230 			ftpd_logwtmpx(ttyline, "", "", NULL, 0, DEAD_PROCESS);
1231 #endif
1232 #ifdef SUPPORT_UTMP
1233 		if (doutmp)
1234 			okwtmp &= ftpd_logout(ttyline);
1235 		if (okwtmp)
1236 			ftpd_logwtmp(ttyline, "", "");
1237 #endif
1238 	}
1239 }
1240 
1241 /*
1242  * Terminate login as previous user (if any), resetting state;
1243  * used when USER command is given or login fails.
1244  */
1245 static void
1246 end_login(void)
1247 {
1248 #ifdef USE_PAM
1249 	int e;
1250 #endif
1251 	logout_utmp();
1252 	show_chdir_messages(-1);		/* flush chdir cache */
1253 	if (pw != NULL && pw->pw_passwd != NULL)
1254 		memset(pw->pw_passwd, 0, strlen(pw->pw_passwd));
1255 	pw = NULL;
1256 	logged_in = 0;
1257 	askpasswd = 0;
1258 	permitted = 0;
1259 	quietmessages = 0;
1260 	gidcount = 0;
1261 	curclass.type = CLASS_REAL;
1262 	(void) seteuid((uid_t)0);
1263 #ifdef	LOGIN_CAP
1264 	setusercontext(NULL, getpwuid(0), 0,
1265 		       LOGIN_SETPRIORITY|LOGIN_SETRESOURCES|LOGIN_SETUMASK);
1266 #endif
1267 #ifdef USE_PAM
1268 	if (pamh) {
1269 		if ((e = pam_setcred(pamh, PAM_DELETE_CRED)) != PAM_SUCCESS)
1270 			syslog(LOG_ERR, "pam_setcred: %s",
1271 			    pam_strerror(pamh, e));
1272 		if ((e = pam_close_session(pamh,0)) != PAM_SUCCESS)
1273 			syslog(LOG_ERR, "pam_close_session: %s",
1274 			    pam_strerror(pamh, e));
1275 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS)
1276 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1277 		pamh = NULL;
1278 	}
1279 #endif
1280 }
1281 
1282 void
1283 pass(const char *passwd)
1284 {
1285 	do_pass(0, 0, passwd);
1286 }
1287 
1288 /*
1289  * Perform the passwd confirmation and login.
1290  *
1291  * If pass_checked is zero, confirm passwd is correct, & ignore pass_rval.
1292  * This is the traditional PASS implementation.
1293  *
1294  * If pass_checked is non-zero, use pass_rval and ignore passwd.
1295  * This is used by auth_pam() which has already parsed PASS.
1296  * This only applies to curclass.type != CLASS_GUEST.
1297  */
1298 static void
1299 do_pass(int pass_checked, int pass_rval, const char *passwd)
1300 {
1301 	int		 rval;
1302 	char		 root[MAXPATHLEN];
1303 #ifdef	LOGIN_CAP
1304 	login_cap_t *lc = NULL;
1305 #endif
1306 #ifdef USE_PAM
1307 	int e;
1308 #endif
1309 
1310 	rval = 1;
1311 
1312 	if (logged_in || askpasswd == 0) {
1313 		reply(503, "Login with USER first.");
1314 		return;
1315 	}
1316 	askpasswd = 0;
1317 	if (curclass.type != CLASS_GUEST) {
1318 			/* "ftp" is the only account allowed with no password */
1319 		if (pw == NULL) {
1320 			rval = 1;	/* failure below */
1321 			goto skip;
1322 		}
1323 		if (pass_checked) {	/* password validated in user() */
1324 			rval = pass_rval;
1325 			goto skip;
1326 		}
1327 #ifdef USE_PAM
1328 		syslog(LOG_ERR, "do_pass: USE_PAM shouldn't get here");
1329 		rval = 1;
1330 		goto skip;
1331 #endif
1332 #if defined(KERBEROS)
1333 		if (klogin(pw, "", hostname, (char *)passwd) == 0) {
1334 			rval = 0;
1335 			goto skip;
1336 		}
1337 #endif
1338 #if defined(KERBEROS5)
1339 		if (k5login(pw, "", hostname, (char *)passwd) == 0) {
1340 			rval = 0;
1341 			goto skip;
1342 		}
1343 #endif
1344 #ifdef SKEY
1345 		if (skey_haskey(pw->pw_name) == 0) {
1346 			char *p;
1347 			int r;
1348 
1349 			p = ftpd_strdup(passwd);
1350 			r = skey_passcheck(pw->pw_name, p);
1351 			free(p);
1352 			if (r != -1) {
1353 				rval = 0;
1354 				goto skip;
1355 			}
1356 		}
1357 #endif
1358 		if (!sflag)
1359 			rval = checkpassword(pw, passwd);
1360 		else
1361 			rval = 1;
1362 
1363  skip:
1364 
1365 			/*
1366 			 * If rval > 0, the user failed the authentication check
1367 			 * above.  If rval == 0, either Kerberos or local
1368 			 * authentication succeeded.
1369 			 */
1370 		if (rval) {
1371 			reply(530, "%s", rval == 2 ? "Password expired." :
1372 			    "Login incorrect.");
1373 			if (logging) {
1374 				syslog(LOG_NOTICE,
1375 				    "FTP LOGIN FAILED FROM %s", remotehost);
1376 				syslog(LOG_AUTHPRIV | LOG_NOTICE,
1377 				    "FTP LOGIN FAILED FROM %s, %s",
1378 				    remotehost, curname);
1379 			}
1380 			pw = NULL;
1381 			if (login_attempts++ >= 5) {
1382 				syslog(LOG_NOTICE,
1383 				    "repeated login failures from %s",
1384 				    remotehost);
1385 				exit(0);
1386 			}
1387 			return;
1388 		}
1389 	}
1390 
1391 			/* password ok; check if anything else prevents login */
1392 	if (! permitted) {
1393 		reply(530, "User %s may not use FTP.", pw->pw_name);
1394 		if (logging)
1395 			syslog(LOG_NOTICE, "FTP LOGIN REFUSED FROM %s, %s",
1396 			    remotehost, pw->pw_name);
1397 		goto bad;
1398 	}
1399 
1400 	login_attempts = 0;		/* this time successful */
1401 	if (setegid((gid_t)pw->pw_gid) < 0) {
1402 		reply(550, "Can't set gid.");
1403 		goto bad;
1404 	}
1405 #ifdef	LOGIN_CAP
1406 	if ((lc = login_getpwclass(pw)) != NULL) {
1407 #ifdef notyet
1408 		char	remote_ip[NI_MAXHOST];
1409 
1410 		if (getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
1411 			remote_ip, sizeof(remote_ip) - 1, NULL, 0,
1412 			NI_NUMERICHOST))
1413 				*remote_ip = 0;
1414 		remote_ip[sizeof(remote_ip) - 1] = 0;
1415 		if (!auth_hostok(lc, remotehost, remote_ip)) {
1416 			syslog(LOG_INFO|LOG_AUTH,
1417 			    "FTP LOGIN FAILED (HOST) as %s: permission denied.",
1418 			    pw->pw_name);
1419 			reply(530, "Permission denied.");
1420 			pw = NULL;
1421 			return;
1422 		}
1423 		if (!auth_timeok(lc, time(NULL))) {
1424 			reply(530, "Login not available right now.");
1425 			pw = NULL;
1426 			return;
1427 		}
1428 #endif
1429 	}
1430 	setsid();
1431 	setusercontext(lc, pw, 0,
1432 		LOGIN_SETLOGIN|LOGIN_SETGROUP|LOGIN_SETPRIORITY|
1433 		LOGIN_SETRESOURCES|LOGIN_SETUMASK);
1434 #else
1435 	(void) initgroups(pw->pw_name, pw->pw_gid);
1436 			/* cache groups for cmds.c::matchgroup() */
1437 #endif
1438 #ifdef USE_PAM
1439 	if (pamh) {
1440 		if ((e = pam_open_session(pamh, 0)) != PAM_SUCCESS) {
1441 			syslog(LOG_ERR, "pam_open_session: %s",
1442 			    pam_strerror(pamh, e));
1443 		} else if ((e = pam_setcred(pamh, PAM_ESTABLISH_CRED))
1444 		    != PAM_SUCCESS) {
1445 			syslog(LOG_ERR, "pam_setcred: %s",
1446 			    pam_strerror(pamh, e));
1447 		}
1448 	}
1449 #endif
1450 	gidcount = getgroups(0, NULL);
1451 	if (gidlist)
1452 		free(gidlist);
1453 	gidlist = malloc(gidcount * sizeof *gidlist);
1454 	gidcount = getgroups(gidcount, gidlist);
1455 
1456 	/* open utmp/wtmp before chroot */
1457 	login_utmp(ttyline, pw->pw_name, remotehost, &his_addr);
1458 
1459 	logged_in = 1;
1460 
1461 	connections = 1;
1462 	if (dopidfile)
1463 		count_users();
1464 	if (curclass.limit != -1 && connections > curclass.limit) {
1465 		if (! EMPTYSTR(curclass.limitfile))
1466 			(void)display_file(conffilename(curclass.limitfile),
1467 			    530);
1468 		reply(530,
1469 		    "User %s access denied, connection limit of " LLF
1470 		    " reached.",
1471 		    pw->pw_name, (LLT)curclass.limit);
1472 		syslog(LOG_NOTICE,
1473 		    "Maximum connection limit of " LLF
1474 		    " for class %s reached, login refused for %s",
1475 		    (LLT)curclass.limit, curclass.classname, pw->pw_name);
1476 		goto bad;
1477 	}
1478 
1479 	homedir[0] = '/';
1480 	switch (curclass.type) {
1481 	case CLASS_GUEST:
1482 			/*
1483 			 * We MUST do a chdir() after the chroot. Otherwise
1484 			 * the old current directory will be accessible as "."
1485 			 * outside the new root!
1486 			 */
1487 		format_path(root,
1488 		    curclass.chroot ? curclass.chroot :
1489 		    anondir ? anondir :
1490 		    pw->pw_dir);
1491 		format_path(homedir,
1492 		    curclass.homedir ? curclass.homedir :
1493 		    "/");
1494 		if (EMPTYSTR(homedir))
1495 			homedir[0] = '/';
1496 		if (EMPTYSTR(root) || chroot(root) < 0) {
1497 			syslog(LOG_NOTICE,
1498 			    "GUEST user %s: can't chroot to %s: %m",
1499 			    pw->pw_name, root);
1500 			goto bad_guest;
1501 		}
1502 		if (chdir(homedir) < 0) {
1503 			syslog(LOG_NOTICE,
1504 			    "GUEST user %s: can't chdir to %s: %m",
1505 			    pw->pw_name, homedir);
1506  bad_guest:
1507 			reply(550, "Can't set guest privileges.");
1508 			goto bad;
1509 		}
1510 		break;
1511 	case CLASS_CHROOT:
1512 		format_path(root,
1513 		    curclass.chroot ? curclass.chroot :
1514 		    pw->pw_dir);
1515 		format_path(homedir,
1516 		    curclass.homedir ? curclass.homedir :
1517 		    "/");
1518 		if (EMPTYSTR(homedir))
1519 			homedir[0] = '/';
1520 		if (EMPTYSTR(root) || chroot(root) < 0) {
1521 			syslog(LOG_NOTICE,
1522 			    "CHROOT user %s: can't chroot to %s: %m",
1523 			    pw->pw_name, root);
1524 			goto bad_chroot;
1525 		}
1526 		if (chdir(homedir) < 0) {
1527 			syslog(LOG_NOTICE,
1528 			    "CHROOT user %s: can't chdir to %s: %m",
1529 			    pw->pw_name, homedir);
1530  bad_chroot:
1531 			reply(550, "Can't change root.");
1532 			goto bad;
1533 		}
1534 		break;
1535 	case CLASS_REAL:
1536 			/* only chroot REAL if explicitly requested */
1537 		if (! EMPTYSTR(curclass.chroot)) {
1538 			format_path(root, curclass.chroot);
1539 			if (EMPTYSTR(root) || chroot(root) < 0) {
1540 				syslog(LOG_NOTICE,
1541 				    "REAL user %s: can't chroot to %s: %m",
1542 				    pw->pw_name, root);
1543 				goto bad_chroot;
1544 			}
1545 		}
1546 		format_path(homedir,
1547 		    curclass.homedir ? curclass.homedir :
1548 		    pw->pw_dir);
1549 		if (EMPTYSTR(homedir) || chdir(homedir) < 0) {
1550 			if (chdir("/") < 0) {
1551 				syslog(LOG_NOTICE,
1552 				    "REAL user %s: can't chdir to %s: %m",
1553 				    pw->pw_name,
1554 				    !EMPTYSTR(homedir) ?  homedir : "/");
1555 				reply(530,
1556 				    "User %s: can't change directory to %s.",
1557 				    pw->pw_name,
1558 				    !EMPTYSTR(homedir) ? homedir : "/");
1559 				goto bad;
1560 			} else {
1561 				reply(-230,
1562 				    "No directory! Logging in with home=/");
1563 				homedir[0] = '/';
1564 			}
1565 		}
1566 		break;
1567 	}
1568 #ifndef LOGIN_CAP
1569 	setsid();
1570 	setlogin(pw->pw_name);
1571 #endif
1572 	if (dropprivs ||
1573 	    (curclass.type != CLASS_REAL &&
1574 	    ntohs(ctrl_addr.su_port) > IPPORT_RESERVED + 1)) {
1575 		dropprivs++;
1576 		if (setgid((gid_t)pw->pw_gid) < 0) {
1577 			reply(550, "Can't set gid.");
1578 			goto bad;
1579 		}
1580 		if (setuid((uid_t)pw->pw_uid) < 0) {
1581 			reply(550, "Can't set uid.");
1582 			goto bad;
1583 		}
1584 	} else {
1585 		if (seteuid((uid_t)pw->pw_uid) < 0) {
1586 			reply(550, "Can't set uid.");
1587 			goto bad;
1588 		}
1589 	}
1590 	setenv("HOME", homedir, 1);
1591 
1592 	if (curclass.type == CLASS_GUEST && passwd[0] == '-')
1593 		quietmessages = 1;
1594 
1595 			/*
1596 			 * Display a login message, if it exists.
1597 			 * N.B. reply(230,) must follow the message.
1598 			 */
1599 	if (! EMPTYSTR(curclass.motd))
1600 		(void)display_file(conffilename(curclass.motd), 230);
1601 	show_chdir_messages(230);
1602 	if (curclass.type == CLASS_GUEST) {
1603 		char *p;
1604 
1605 		reply(230, "Guest login ok, access restrictions apply.");
1606 #if defined(HAVE_SETPROCTITLE)
1607 		snprintf(proctitle, sizeof(proctitle),
1608 		    "%s: anonymous/%s", remotehost, passwd);
1609 		setproctitle("%s", proctitle);
1610 #endif /* defined(HAVE_SETPROCTITLE) */
1611 		if (logging)
1612 			syslog(LOG_INFO,
1613 			"ANONYMOUS FTP LOGIN FROM %s, %s (class: %s, type: %s)",
1614 			    remotehost, passwd,
1615 			    curclass.classname, CURCLASSTYPE);
1616 			/* store guest password reply into pw_passwd */
1617 		REASSIGN(pw->pw_passwd, ftpd_strdup(passwd));
1618 		for (p = pw->pw_passwd; *p; p++)
1619 			if (!isgraph((unsigned char)*p))
1620 				*p = '_';
1621 	} else {
1622 		reply(230, "User %s logged in.", pw->pw_name);
1623 #if defined(HAVE_SETPROCTITLE)
1624 		snprintf(proctitle, sizeof(proctitle),
1625 		    "%s: %s", remotehost, pw->pw_name);
1626 		setproctitle("%s", proctitle);
1627 #endif /* defined(HAVE_SETPROCTITLE) */
1628 		if (logging)
1629 			syslog(LOG_INFO,
1630 			    "FTP LOGIN FROM %s as %s (class: %s, type: %s)",
1631 			    remotehost, pw->pw_name,
1632 			    curclass.classname, CURCLASSTYPE);
1633 	}
1634 	(void) umask(curclass.umask);
1635 #ifdef	LOGIN_CAP
1636 	login_close(lc);
1637 #endif
1638 	return;
1639 
1640  bad:
1641 #ifdef	LOGIN_CAP
1642 	login_close(lc);
1643 #endif
1644 			/* Forget all about it... */
1645 	end_login();
1646 }
1647 
1648 void
1649 retrieve(char *argv[], const char *name)
1650 {
1651 	FILE *fin, *dout;
1652 	struct stat st;
1653 	int (*closefunc)(FILE *) = NULL;
1654 	int dolog, sendrv, closerv, stderrfd, isconversion, isdata, isls;
1655 	struct timeval start, finish, td, *tdp;
1656 	struct rusage rusage_before, rusage_after;
1657 	const char *dispname;
1658 	char *error;
1659 
1660 	sendrv = closerv = stderrfd = -1;
1661 	isconversion = isdata = isls = dolog = 0;
1662 	tdp = NULL;
1663 	dispname = name;
1664 	fin = dout = NULL;
1665 	error = NULL;
1666 	if (argv == NULL) {		/* if not running a command ... */
1667 		dolog = 1;
1668 		isdata = 1;
1669 		fin = fopen(name, "r");
1670 		closefunc = fclose;
1671 		if (fin == NULL)	/* doesn't exist?; try a conversion */
1672 			argv = do_conversion(name);
1673 		if (argv != NULL) {
1674 			isconversion++;
1675 			syslog(LOG_DEBUG, "get command: '%s' on '%s'",
1676 			    argv[0], name);
1677 		}
1678 	}
1679 	if (argv != NULL) {
1680 		char temp[MAXPATHLEN];
1681 
1682 		if (strcmp(argv[0], INTERNAL_LS) == 0) {
1683 			isls = 1;
1684 			stderrfd = -1;
1685 		} else {
1686 			(void)snprintf(temp, sizeof(temp), "%s", TMPFILE);
1687 			stderrfd = mkstemp(temp);
1688 			if (stderrfd != -1)
1689 				(void)unlink(temp);
1690 		}
1691 		dispname = argv[0];
1692 		fin = ftpd_popen(argv, "r", stderrfd);
1693 		closefunc = ftpd_pclose;
1694 		st.st_size = -1;
1695 		st.st_blksize = BUFSIZ;
1696 	}
1697 	if (fin == NULL) {
1698 		if (errno != 0) {
1699 			perror_reply(550, dispname);
1700 			if (dolog)
1701 				logxfer("get", -1, name, NULL, NULL,
1702 				    strerror(errno));
1703 		}
1704 		goto cleanupretrieve;
1705 	}
1706 	byte_count = -1;
1707 	if (argv == NULL
1708 	    && (fstat(fileno(fin), &st) < 0 || !S_ISREG(st.st_mode))) {
1709 		error = "Not a plain file";
1710 		reply(550, "%s: %s.", dispname, error);
1711 		goto done;
1712 	}
1713 	if (restart_point) {
1714 		if (type == TYPE_A) {
1715 			off_t i;
1716 			int c;
1717 
1718 			for (i = 0; i < restart_point; i++) {
1719 				if ((c=getc(fin)) == EOF) {
1720 					error = strerror(errno);
1721 					perror_reply(550, dispname);
1722 					goto done;
1723 				}
1724 				if (c == '\n')
1725 					i++;
1726 			}
1727 		} else if (lseek(fileno(fin), restart_point, SEEK_SET) < 0) {
1728 			error = strerror(errno);
1729 			perror_reply(550, dispname);
1730 			goto done;
1731 		}
1732 	}
1733 	dout = dataconn(dispname, st.st_size, "w");
1734 	if (dout == NULL)
1735 		goto done;
1736 
1737 	(void)getrusage(RUSAGE_SELF, &rusage_before);
1738 	(void)gettimeofday(&start, NULL);
1739 	sendrv = send_data(fin, dout, &st, isdata);
1740 	(void)gettimeofday(&finish, NULL);
1741 	(void)getrusage(RUSAGE_SELF, &rusage_after);
1742 	closedataconn(dout);		/* close now to affect timing stats */
1743 	timersub(&finish, &start, &td);
1744 	tdp = &td;
1745  done:
1746 	if (dolog) {
1747 		logxfer("get", byte_count, name, NULL, tdp, error);
1748 		if (tdp != NULL)
1749 			logrusage(&rusage_before, &rusage_after);
1750 	}
1751 	closerv = (*closefunc)(fin);
1752 	if (sendrv == 0) {
1753 		FILE *errf;
1754 		struct stat sb;
1755 
1756 		if (!isls && argv != NULL && closerv != 0) {
1757 			reply(-226,
1758 			    "Command returned an exit status of %d",
1759 			    closerv);
1760 			if (isconversion)
1761 				syslog(LOG_WARNING,
1762 				    "retrieve command: '%s' returned %d",
1763 				    argv[0], closerv);
1764 		}
1765 		if (!isls && argv != NULL && stderrfd != -1 &&
1766 		    (fstat(stderrfd, &sb) == 0) && sb.st_size > 0 &&
1767 		    ((errf = fdopen(stderrfd, "r")) != NULL)) {
1768 			char *cp, line[LINE_MAX];
1769 
1770 			reply(-226, "Command error messages:");
1771 			rewind(errf);
1772 			while (fgets(line, sizeof(line), errf) != NULL) {
1773 				if ((cp = strchr(line, '\n')) != NULL)
1774 					*cp = '\0';
1775 				reply(0, "  %s", line);
1776 			}
1777 			(void) fflush(stdout);
1778 			(void) fclose(errf);
1779 				/* a reply(226,) must follow */
1780 		}
1781 		reply(226, "Transfer complete.");
1782 	}
1783  cleanupretrieve:
1784 	if (stderrfd != -1)
1785 		(void)close(stderrfd);
1786 	if (isconversion)
1787 		free(argv);
1788 }
1789 
1790 void
1791 store(const char *name, const char *fmode, int unique)
1792 {
1793 	FILE *fout, *din;
1794 	struct stat st;
1795 	int (*closefunc)(FILE *);
1796 	struct timeval start, finish, td, *tdp;
1797 	char *desc, *error;
1798 
1799 	din = NULL;
1800 	desc = (*fmode == 'w') ? "put" : "append";
1801 	error = NULL;
1802 	if (unique && stat(name, &st) == 0 &&
1803 	    (name = gunique(name)) == NULL) {
1804 		logxfer(desc, -1, name, NULL, NULL,
1805 		    "cannot create unique file");
1806 		goto cleanupstore;
1807 	}
1808 
1809 	if (restart_point)
1810 		fmode = "r+";
1811 	fout = fopen(name, fmode);
1812 	closefunc = fclose;
1813 	tdp = NULL;
1814 	if (fout == NULL) {
1815 		perror_reply(553, name);
1816 		logxfer(desc, -1, name, NULL, NULL, strerror(errno));
1817 		goto cleanupstore;
1818 	}
1819 	byte_count = -1;
1820 	if (restart_point) {
1821 		if (type == TYPE_A) {
1822 			off_t i;
1823 			int c;
1824 
1825 			for (i = 0; i < restart_point; i++) {
1826 				if ((c=getc(fout)) == EOF) {
1827 					error = strerror(errno);
1828 					perror_reply(550, name);
1829 					goto done;
1830 				}
1831 				if (c == '\n')
1832 					i++;
1833 			}
1834 			/*
1835 			 * We must do this seek to "current" position
1836 			 * because we are changing from reading to
1837 			 * writing.
1838 			 */
1839 			if (fseek(fout, 0L, SEEK_CUR) < 0) {
1840 				error = strerror(errno);
1841 				perror_reply(550, name);
1842 				goto done;
1843 			}
1844 		} else if (lseek(fileno(fout), restart_point, SEEK_SET) < 0) {
1845 			error = strerror(errno);
1846 			perror_reply(550, name);
1847 			goto done;
1848 		}
1849 	}
1850 	din = dataconn(name, (off_t)-1, "r");
1851 	if (din == NULL)
1852 		goto done;
1853 	(void)gettimeofday(&start, NULL);
1854 	if (receive_data(din, fout) == 0) {
1855 		if (unique)
1856 			reply(226, "Transfer complete (unique file name:%s).",
1857 			    name);
1858 		else
1859 			reply(226, "Transfer complete.");
1860 	}
1861 	(void)gettimeofday(&finish, NULL);
1862 	closedataconn(din);		/* close now to affect timing stats */
1863 	timersub(&finish, &start, &td);
1864 	tdp = &td;
1865  done:
1866 	logxfer(desc, byte_count, name, NULL, tdp, error);
1867 	(*closefunc)(fout);
1868  cleanupstore:
1869 	;
1870 }
1871 
1872 static FILE *
1873 getdatasock(const char *fmode)
1874 {
1875 	int		on, s, t, tries;
1876 	in_port_t	port;
1877 
1878 	on = 1;
1879 	if (data >= 0)
1880 		return (fdopen(data, fmode));
1881 	if (! dropprivs)
1882 		(void) seteuid((uid_t)0);
1883 	s = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
1884 	if (s < 0)
1885 		goto bad;
1886 	if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR,
1887 	    (char *) &on, sizeof(on)) < 0)
1888 		goto bad;
1889 	if (setsockopt(s, SOL_SOCKET, SO_KEEPALIVE,
1890 	    (char *) &on, sizeof(on)) < 0)
1891 		goto bad;
1892 			/* anchor socket to avoid multi-homing problems */
1893 	data_source = ctrl_addr;
1894 			/*
1895 			 * By default source port for PORT connctions is
1896 			 * ctrlport-1 (see RFC959 section 5.2).
1897 			 * However, if privs have been dropped and that
1898 			 * would be < IPPORT_RESERVED, use a random port
1899 			 * instead.
1900 			 */
1901 	if (dataport)
1902 		port = dataport;
1903 	else
1904 		port = ntohs(ctrl_addr.su_port) - 1;
1905 	if (dropprivs && port < IPPORT_RESERVED)
1906 		port = 0;		/* use random port */
1907 	data_source.su_port = htons(port);
1908 
1909 	for (tries = 1; ; tries++) {
1910 		if (bind(s, (struct sockaddr *)&data_source.si_su,
1911 		    data_source.su_len) >= 0)
1912 			break;
1913 		if (errno != EADDRINUSE || tries > 10)
1914 			goto bad;
1915 		sleep(tries);
1916 	}
1917 	if (! dropprivs)
1918 		(void) seteuid((uid_t)pw->pw_uid);
1919 #ifdef IP_TOS
1920 	if (!mapped && ctrl_addr.su_family == AF_INET) {
1921 		on = IPTOS_THROUGHPUT;
1922 		if (setsockopt(s, IPPROTO_IP, IP_TOS, (char *)&on,
1923 			       sizeof(int)) < 0)
1924 			syslog(LOG_WARNING, "setsockopt (IP_TOS): %m");
1925 	}
1926 #endif
1927 	return (fdopen(s, fmode));
1928  bad:
1929 		/* Return the real value of errno (close may change it) */
1930 	t = errno;
1931 	if (! dropprivs)
1932 		(void) seteuid((uid_t)pw->pw_uid);
1933 	(void) close(s);
1934 	errno = t;
1935 	return (NULL);
1936 }
1937 
1938 FILE *
1939 dataconn(const char *name, off_t size, const char *fmode)
1940 {
1941 	char sizebuf[32];
1942 	FILE *file;
1943 	int retry, tos, keepalive, conerrno;
1944 
1945 	file_size = size;
1946 	byte_count = 0;
1947 	if (size != (off_t) -1)
1948 		(void)snprintf(sizebuf, sizeof(sizebuf), " (" LLF " byte%s)",
1949 		    (LLT)size, PLURAL(size));
1950 	else
1951 		sizebuf[0] = '\0';
1952 	if (pdata >= 0) {
1953 		struct sockinet from;
1954 		int s;
1955 		socklen_t fromlen = sizeof(from.su_len);
1956 
1957 		(void) alarm(curclass.timeout);
1958 		s = accept(pdata, (struct sockaddr *)&from.si_su, &fromlen);
1959 		(void) alarm(0);
1960 		if (s < 0) {
1961 			reply(425, "Can't open data connection.");
1962 			(void) close(pdata);
1963 			pdata = -1;
1964 			return (NULL);
1965 		}
1966 		(void) close(pdata);
1967 		pdata = s;
1968 		switch (from.su_family) {
1969 		case AF_INET:
1970 #ifdef IP_TOS
1971 			if (!mapped) {
1972 				tos = IPTOS_THROUGHPUT;
1973 				(void) setsockopt(s, IPPROTO_IP, IP_TOS,
1974 				    (char *)&tos, sizeof(int));
1975 			}
1976 			break;
1977 #endif
1978 		}
1979 		/* Set keepalives on the socket to detect dropped conns. */
1980 #ifdef SO_KEEPALIVE
1981 		keepalive = 1;
1982 		(void) setsockopt(s, SOL_SOCKET, SO_KEEPALIVE,
1983 		    (char *)&keepalive, sizeof(int));
1984 #endif
1985 		reply(150, "Opening %s mode data connection for '%s'%s.",
1986 		     type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
1987 		return (fdopen(pdata, fmode));
1988 	}
1989 	if (data >= 0) {
1990 		reply(125, "Using existing data connection for '%s'%s.",
1991 		    name, sizebuf);
1992 		usedefault = 1;
1993 		return (fdopen(data, fmode));
1994 	}
1995 	if (usedefault)
1996 		data_dest = his_addr;
1997 	usedefault = 1;
1998 	retry = conerrno = 0;
1999 	do {
2000 		file = getdatasock(fmode);
2001 		if (file == NULL) {
2002 			char hbuf[NI_MAXHOST];
2003 			char pbuf[NI_MAXSERV];
2004 
2005 			if (getnameinfo((struct sockaddr *)&data_source.si_su,
2006 			    data_source.su_len, hbuf, sizeof(hbuf), pbuf,
2007 			    sizeof(pbuf), NI_NUMERICHOST | NI_NUMERICSERV))
2008 				strlcpy(hbuf, "?", sizeof(hbuf));
2009 			reply(425, "Can't create data socket (%s,%s): %s.",
2010 			      hbuf, pbuf, strerror(errno));
2011 			return (NULL);
2012 		}
2013 		data = fileno(file);
2014 		conerrno = 0;
2015 		if (connect(data, (struct sockaddr *)&data_dest.si_su,
2016 		    data_dest.su_len) == 0)
2017 			break;
2018 		conerrno = errno;
2019 		(void) fclose(file);
2020 		file = NULL;
2021 		data = -1;
2022 		if (conerrno == EADDRINUSE) {
2023 			sleep((unsigned) swaitint);
2024 			retry += swaitint;
2025 		} else {
2026 			break;
2027 		}
2028 	} while (retry <= swaitmax);
2029 	if (conerrno != 0) {
2030 		perror_reply(425, "Can't build data connection");
2031 		return (NULL);
2032 	}
2033 	reply(150, "Opening %s mode data connection for '%s'%s.",
2034 	     type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
2035 	return (file);
2036 }
2037 
2038 void
2039 closedataconn(FILE *fd)
2040 {
2041 
2042 	if (fd == NULL)
2043 		return;
2044 	(void)fclose(fd);
2045 	data = -1;
2046 	if (pdata >= 0)
2047 		(void)close(pdata);
2048 	pdata = -1;
2049 }
2050 
2051 int
2052 write_data(int fd, char *buf, size_t size, off_t *bufrem,
2053     struct timeval *then, int isdata)
2054 {
2055 	struct timeval now, td;
2056 	ssize_t c;
2057 
2058 	while (size > 0) {
2059 		c = size;
2060 		if (curclass.writesize) {
2061 			if (curclass.writesize < c)
2062 				c = curclass.writesize;
2063 		}
2064 		if (curclass.rateget) {
2065 			if (*bufrem < c)
2066 				c = *bufrem;
2067 		}
2068 		(void) alarm(curclass.timeout);
2069 		c = write(fd, buf, c);
2070 		if (c <= 0)
2071 			return (1);
2072 		buf += c;
2073 		size -= c;
2074 		byte_count += c;
2075 		if (isdata) {
2076 			total_data_out += c;
2077 			total_data += c;
2078 		}
2079 		total_bytes_out += c;
2080 		total_bytes += c;
2081 		if (curclass.rateget) {
2082 			*bufrem -= c;
2083 			if (*bufrem == 0) {
2084 				(void)gettimeofday(&now, NULL);
2085 				timersub(&now, then, &td);
2086 				if (td.tv_sec == 0) {
2087 					usleep(1000000 - td.tv_usec);
2088 					(void)gettimeofday(then, NULL);
2089 				} else
2090 					*then = now;
2091 				*bufrem = curclass.rateget;
2092 			}
2093 		}
2094 	}
2095 	return (0);
2096 }
2097 
2098 static enum send_status
2099 send_data_with_read(int filefd, int netfd, const struct stat *st, int isdata)
2100 {
2101 	struct timeval then;
2102 	off_t bufrem;
2103 	size_t readsize;
2104 	char *buf;
2105 	int c, error;
2106 
2107 	if (curclass.readsize)
2108 		readsize = curclass.readsize;
2109 	else
2110 		readsize = (size_t)st->st_blksize;
2111 	if ((buf = malloc(readsize)) == NULL) {
2112 		perror_reply(451, "Local resource failure: malloc");
2113 		return (SS_NO_TRANSFER);
2114 	}
2115 
2116 	if (curclass.rateget) {
2117 		bufrem = curclass.rateget;
2118 		(void)gettimeofday(&then, NULL);
2119 	}
2120 	while (1) {
2121 		(void) alarm(curclass.timeout);
2122 		c = read(filefd, buf, readsize);
2123 		if (c == 0)
2124 			error = SS_SUCCESS;
2125 		else if (c < 0)
2126 			error = SS_FILE_ERROR;
2127 		else if (write_data(netfd, buf, c, &bufrem, &then, isdata))
2128 			error = SS_DATA_ERROR;
2129 		else if (urgflag && handleoobcmd())
2130 			error = SS_ABORTED;
2131 		else
2132 			continue;
2133 
2134 		free(buf);
2135 		return (error);
2136 	}
2137 }
2138 
2139 static enum send_status
2140 send_data_with_mmap(int filefd, int netfd, const struct stat *st, int isdata)
2141 {
2142 	struct timeval then;
2143 	off_t bufrem, filesize, off, origoff;
2144 	size_t mapsize, winsize;
2145 	int error, sendbufsize, sendlowat;
2146 	void *win;
2147 
2148 	if (curclass.sendbufsize) {
2149 		sendbufsize = curclass.sendbufsize;
2150 		if (setsockopt(netfd, SOL_SOCKET, SO_SNDBUF,
2151 		    &sendbufsize, sizeof(int)) == -1)
2152 			syslog(LOG_WARNING, "setsockopt(SO_SNDBUF, %d): %m",
2153 			    sendbufsize);
2154 	}
2155 
2156 	if (curclass.sendlowat) {
2157 		sendlowat = curclass.sendlowat;
2158 		if (setsockopt(netfd, SOL_SOCKET, SO_SNDLOWAT,
2159 		    &sendlowat, sizeof(int)) == -1)
2160 			syslog(LOG_WARNING, "setsockopt(SO_SNDLOWAT, %d): %m",
2161 			    sendlowat);
2162 	}
2163 
2164 	winsize = curclass.mmapsize;
2165 	filesize = st->st_size;
2166 	if (ftpd_debug)
2167 		syslog(LOG_INFO, "mmapsize = %ld, writesize = %ld",
2168 		    (long)winsize, (long)curclass.writesize);
2169 	if (winsize == 0)
2170 		goto try_read;
2171 
2172 	off = lseek(filefd, (off_t)0, SEEK_CUR);
2173 	if (off == -1)
2174 		goto try_read;
2175 
2176 	origoff = off;
2177 	if (curclass.rateget) {
2178 		bufrem = curclass.rateget;
2179 		(void)gettimeofday(&then, NULL);
2180 	}
2181 	while (1) {
2182 		mapsize = MIN(filesize - off, winsize);
2183 		if (mapsize == 0)
2184 			break;
2185 		win = mmap(NULL, mapsize, PROT_READ,
2186 		    MAP_FILE|MAP_SHARED, filefd, off);
2187 		if (win == MAP_FAILED) {
2188 			if (off == origoff)
2189 				goto try_read;
2190 			return (SS_FILE_ERROR);
2191 		}
2192 		(void) madvise(win, mapsize, MADV_SEQUENTIAL);
2193 		error = write_data(netfd, win, mapsize, &bufrem, &then,
2194 		    isdata);
2195 		(void) madvise(win, mapsize, MADV_DONTNEED);
2196 		munmap(win, mapsize);
2197 		if (urgflag && handleoobcmd())
2198 			return (SS_ABORTED);
2199 		if (error)
2200 			return (SS_DATA_ERROR);
2201 		off += mapsize;
2202 	}
2203 	return (SS_SUCCESS);
2204 
2205  try_read:
2206 	return (send_data_with_read(filefd, netfd, st, isdata));
2207 }
2208 
2209 /*
2210  * Transfer the contents of "instr" to "outstr" peer using the appropriate
2211  * encapsulation of the data subject to Mode, Structure, and Type.
2212  *
2213  * NB: Form isn't handled.
2214  */
2215 static int
2216 send_data(FILE *instr, FILE *outstr, const struct stat *st, int isdata)
2217 {
2218 	int	 c, filefd, netfd, rval;
2219 
2220 	urgflag = 0;
2221 	transflag = 1;
2222 	rval = -1;
2223 
2224 	switch (type) {
2225 
2226 	case TYPE_A:
2227  /* XXXLUKEM: rate limit ascii send (get) */
2228 		(void) alarm(curclass.timeout);
2229 		while ((c = getc(instr)) != EOF) {
2230 			if (urgflag && handleoobcmd())
2231 				goto cleanup_send_data;
2232 			byte_count++;
2233 			if (c == '\n') {
2234 				if (ferror(outstr))
2235 					goto data_err;
2236 				(void) putc('\r', outstr);
2237 				if (isdata) {
2238 					total_data_out++;
2239 					total_data++;
2240 				}
2241 				total_bytes_out++;
2242 				total_bytes++;
2243 			}
2244 			(void) putc(c, outstr);
2245 			if (isdata) {
2246 				total_data_out++;
2247 				total_data++;
2248 			}
2249 			total_bytes_out++;
2250 			total_bytes++;
2251 			if ((byte_count % 4096) == 0)
2252 				(void) alarm(curclass.timeout);
2253 		}
2254 		(void) alarm(0);
2255 		fflush(outstr);
2256 		if (ferror(instr))
2257 			goto file_err;
2258 		if (ferror(outstr))
2259 			goto data_err;
2260 		rval = 0;
2261 		goto cleanup_send_data;
2262 
2263 	case TYPE_I:
2264 	case TYPE_L:
2265 		filefd = fileno(instr);
2266 		netfd = fileno(outstr);
2267 		switch (send_data_with_mmap(filefd, netfd, st, isdata)) {
2268 
2269 		case SS_SUCCESS:
2270 			break;
2271 
2272 		case SS_ABORTED:
2273 		case SS_NO_TRANSFER:
2274 			goto cleanup_send_data;
2275 
2276 		case SS_FILE_ERROR:
2277 			goto file_err;
2278 
2279 		case SS_DATA_ERROR:
2280 			goto data_err;
2281 		}
2282 		rval = 0;
2283 		goto cleanup_send_data;
2284 
2285 	default:
2286 		reply(550, "Unimplemented TYPE %d in send_data", type);
2287 		goto cleanup_send_data;
2288 	}
2289 
2290  data_err:
2291 	(void) alarm(0);
2292 	perror_reply(426, "Data connection");
2293 	goto cleanup_send_data;
2294 
2295  file_err:
2296 	(void) alarm(0);
2297 	perror_reply(551, "Error on input file");
2298 	goto cleanup_send_data;
2299 
2300  cleanup_send_data:
2301 	(void) alarm(0);
2302 	transflag = 0;
2303 	urgflag = 0;
2304 	if (isdata) {
2305 		total_files_out++;
2306 		total_files++;
2307 	}
2308 	total_xfers_out++;
2309 	total_xfers++;
2310 	return (rval);
2311 }
2312 
2313 /*
2314  * Transfer data from peer to "outstr" using the appropriate encapulation of
2315  * the data subject to Mode, Structure, and Type.
2316  *
2317  * N.B.: Form isn't handled.
2318  */
2319 static int
2320 receive_data(FILE *instr, FILE *outstr)
2321 {
2322 	int	c, netfd, filefd, rval;
2323 	int	volatile bare_lfs;
2324 	off_t	byteswritten;
2325 	char	*buf;
2326 	size_t	readsize;
2327 	struct sigaction sa, sa_saved;
2328 	struct stat st;
2329 
2330 	memset(&sa, 0, sizeof(sa));
2331 	sigfillset(&sa.sa_mask);
2332 	sa.sa_flags = SA_RESTART;
2333 	sa.sa_handler = lostconn;
2334 	(void) sigaction(SIGALRM, &sa, &sa_saved);
2335 
2336 	bare_lfs = 0;
2337 	urgflag = 0;
2338 	transflag = 1;
2339 	rval = -1;
2340 	byteswritten = 0;
2341 	buf = NULL;
2342 
2343 #define FILESIZECHECK(x) \
2344 			do { \
2345 				if (curclass.maxfilesize != -1 && \
2346 				    (x) > curclass.maxfilesize) { \
2347 					errno = EFBIG; \
2348 					goto file_err; \
2349 				} \
2350 			} while (0)
2351 
2352 	switch (type) {
2353 
2354 	case TYPE_I:
2355 	case TYPE_L:
2356 		netfd = fileno(instr);
2357 		filefd = fileno(outstr);
2358 		(void) alarm(curclass.timeout);
2359 		if (curclass.readsize)
2360 			readsize = curclass.readsize;
2361 		else if (fstat(filefd, &st))
2362 			readsize = (size_t)st.st_blksize;
2363 		else
2364 			readsize = BUFSIZ;
2365 		if ((buf = malloc(readsize)) == NULL) {
2366 			perror_reply(451, "Local resource failure: malloc");
2367 			goto cleanup_recv_data;
2368 		}
2369 		if (curclass.rateput) {
2370 			while (1) {
2371 				int d;
2372 				struct timeval then, now, td;
2373 				off_t bufrem;
2374 
2375 				(void)gettimeofday(&then, NULL);
2376 				errno = c = d = 0;
2377 				for (bufrem = curclass.rateput; bufrem > 0; ) {
2378 					if ((c = read(netfd, buf,
2379 					    MIN(readsize, bufrem))) <= 0)
2380 						goto recvdone;
2381 					if (urgflag && handleoobcmd())
2382 						goto cleanup_recv_data;
2383 					FILESIZECHECK(byte_count + c);
2384 					if ((d = write(filefd, buf, c)) != c)
2385 						goto file_err;
2386 					(void) alarm(curclass.timeout);
2387 					bufrem -= c;
2388 					byte_count += c;
2389 					total_data_in += c;
2390 					total_data += c;
2391 					total_bytes_in += c;
2392 					total_bytes += c;
2393 				}
2394 				(void)gettimeofday(&now, NULL);
2395 				timersub(&now, &then, &td);
2396 				if (td.tv_sec == 0)
2397 					usleep(1000000 - td.tv_usec);
2398 			}
2399 		} else {
2400 			while ((c = read(netfd, buf, readsize)) > 0) {
2401 				if (urgflag && handleoobcmd())
2402 					goto cleanup_recv_data;
2403 				FILESIZECHECK(byte_count + c);
2404 				if (write(filefd, buf, c) != c)
2405 					goto file_err;
2406 				(void) alarm(curclass.timeout);
2407 				byte_count += c;
2408 				total_data_in += c;
2409 				total_data += c;
2410 				total_bytes_in += c;
2411 				total_bytes += c;
2412 			}
2413 		}
2414  recvdone:
2415 		if (c < 0)
2416 			goto data_err;
2417 		rval = 0;
2418 		goto cleanup_recv_data;
2419 
2420 	case TYPE_E:
2421 		reply(553, "TYPE E not implemented.");
2422 		goto cleanup_recv_data;
2423 
2424 	case TYPE_A:
2425 		(void) alarm(curclass.timeout);
2426  /* XXXLUKEM: rate limit ascii receive (put) */
2427 		while ((c = getc(instr)) != EOF) {
2428 			if (urgflag && handleoobcmd())
2429 				goto cleanup_recv_data;
2430 			byte_count++;
2431 			total_data_in++;
2432 			total_data++;
2433 			total_bytes_in++;
2434 			total_bytes++;
2435 			if ((byte_count % 4096) == 0)
2436 				(void) alarm(curclass.timeout);
2437 			if (c == '\n')
2438 				bare_lfs++;
2439 			while (c == '\r') {
2440 				if (ferror(outstr))
2441 					goto data_err;
2442 				if ((c = getc(instr)) != '\n') {
2443 					byte_count++;
2444 					total_data_in++;
2445 					total_data++;
2446 					total_bytes_in++;
2447 					total_bytes++;
2448 					if ((byte_count % 4096) == 0)
2449 						(void) alarm(curclass.timeout);
2450 					byteswritten++;
2451 					FILESIZECHECK(byteswritten);
2452 					(void) putc ('\r', outstr);
2453 					if (c == '\0' || c == EOF)
2454 						goto contin2;
2455 				}
2456 			}
2457 			byteswritten++;
2458 			FILESIZECHECK(byteswritten);
2459 			(void) putc(c, outstr);
2460  contin2:	;
2461 		}
2462 		(void) alarm(0);
2463 		fflush(outstr);
2464 		if (ferror(instr))
2465 			goto data_err;
2466 		if (ferror(outstr))
2467 			goto file_err;
2468 		if (bare_lfs) {
2469 			reply(-226,
2470 			    "WARNING! %d bare linefeeds received in ASCII mode",
2471 			    bare_lfs);
2472 			reply(0, "File may not have transferred correctly.");
2473 		}
2474 		rval = 0;
2475 		goto cleanup_recv_data;
2476 
2477 	default:
2478 		reply(550, "Unimplemented TYPE %d in receive_data", type);
2479 		goto cleanup_recv_data;
2480 	}
2481 #undef FILESIZECHECK
2482 
2483  data_err:
2484 	(void) alarm(0);
2485 	perror_reply(426, "Data Connection");
2486 	goto cleanup_recv_data;
2487 
2488  file_err:
2489 	(void) alarm(0);
2490 	perror_reply(452, "Error writing file");
2491 	goto cleanup_recv_data;
2492 
2493  cleanup_recv_data:
2494 	(void) alarm(0);
2495 	(void) sigaction(SIGALRM, &sa_saved, NULL);
2496 	if (buf)
2497 		free(buf);
2498 	transflag = 0;
2499 	urgflag = 0;
2500 	total_files_in++;
2501 	total_files++;
2502 	total_xfers_in++;
2503 	total_xfers++;
2504 	return (rval);
2505 }
2506 
2507 void
2508 statcmd(void)
2509 {
2510 	struct sockinet *su = NULL;
2511 	static char hbuf[NI_MAXHOST], sbuf[NI_MAXSERV];
2512 	u_char *a, *p;
2513 	int ispassive, af;
2514 	off_t otbi, otbo, otb;
2515 
2516 	a = p = (u_char *)NULL;
2517 
2518 	reply(-211, "%s FTP server status:", hostname);
2519 	reply(0, "Version: %s", EMPTYSTR(version) ? "<suppressed>" : version);
2520 	hbuf[0] = '\0';
2521 	if (!getnameinfo((struct sockaddr *)&his_addr.si_su, his_addr.su_len,
2522 			hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST)
2523 	    && strcmp(remotehost, hbuf) != 0)
2524 		reply(0, "Connected to %s (%s)", remotehost, hbuf);
2525 	else
2526 		reply(0, "Connected to %s", remotehost);
2527 
2528 	if (logged_in) {
2529 		if (curclass.type == CLASS_GUEST)
2530 			reply(0, "Logged in anonymously");
2531 		else
2532 			reply(0, "Logged in as %s%s", pw->pw_name,
2533 			    curclass.type == CLASS_CHROOT ? " (chroot)" : "");
2534 	} else if (askpasswd)
2535 		reply(0, "Waiting for password");
2536 	else
2537 		reply(0, "Waiting for user name");
2538 	cprintf(stdout, "    TYPE: %s", typenames[type]);
2539 	if (type == TYPE_A || type == TYPE_E)
2540 		cprintf(stdout, ", FORM: %s", formnames[form]);
2541 	if (type == TYPE_L) {
2542 #if NBBY == 8
2543 		cprintf(stdout, " %d", NBBY);
2544 #else
2545 			/* XXX: `bytesize' needs to be defined in this case */
2546 		cprintf(stdout, " %d", bytesize);
2547 #endif
2548 	}
2549 	cprintf(stdout, "; STRUcture: %s; transfer MODE: %s\r\n",
2550 	    strunames[stru], modenames[mode]);
2551 	ispassive = 0;
2552 	if (data != -1) {
2553 		reply(0, "Data connection open");
2554 		su = NULL;
2555 	} else if (pdata != -1) {
2556 		reply(0, "in Passive mode");
2557 		if (curclass.advertise.su_len != 0)
2558 			su = &curclass.advertise;
2559 		else
2560 			su = &pasv_addr;
2561 		ispassive = 1;
2562 		goto printaddr;
2563 	} else if (usedefault == 0) {
2564 		su = (struct sockinet *)&data_dest;
2565 
2566 		if (epsvall) {
2567 			reply(0, "EPSV only mode (EPSV ALL)");
2568 			goto epsvonly;
2569 		}
2570  printaddr:
2571 							/* PASV/PORT */
2572 		if (su->su_family == AF_INET) {
2573 			a = (u_char *) &su->su_addr;
2574 			p = (u_char *) &su->su_port;
2575 #define UC(b) (((int) b) & 0xff)
2576 			reply(0, "%s (%d,%d,%d,%d,%d,%d)",
2577 				ispassive ? "PASV" : "PORT" ,
2578 				UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
2579 				UC(p[0]), UC(p[1]));
2580 		}
2581 
2582 							/* LPSV/LPRT */
2583 	    {
2584 		int alen, i;
2585 
2586 		alen = 0;
2587 		switch (su->su_family) {
2588 		case AF_INET:
2589 			a = (u_char *) &su->su_addr;
2590 			p = (u_char *) &su->su_port;
2591 			alen = sizeof(su->su_addr);
2592 			af = 4;
2593 			break;
2594 #ifdef INET6
2595 		case AF_INET6:
2596 			a = (u_char *) &su->su_6addr;
2597 			p = (u_char *) &su->su_port;
2598 			alen = sizeof(su->su_6addr);
2599 			af = 6;
2600 			break;
2601 #endif
2602 		default:
2603 			af = 0;
2604 			break;
2605 		}
2606 		if (af) {
2607 			cprintf(stdout, "    %s (%d,%d",
2608 			    ispassive ? "LPSV" : "LPRT", af, alen);
2609 			for (i = 0; i < alen; i++)
2610 				cprintf(stdout, ",%d", UC(a[i]));
2611 			cprintf(stdout, ",%d,%d,%d)\r\n",
2612 			    2, UC(p[0]), UC(p[1]));
2613 #undef UC
2614 		}
2615 	    }
2616 
2617 		/* EPRT/EPSV */
2618  epsvonly:
2619 		af = af2epsvproto(su->su_family);
2620 		hbuf[0] = '\0';
2621 		if (af > 0) {
2622 			struct sockinet tmp;
2623 
2624 			tmp = *su;
2625 #ifdef INET6
2626 			if (tmp.su_family == AF_INET6)
2627 				tmp.su_scope_id = 0;
2628 #endif
2629 			if (getnameinfo((struct sockaddr *)&tmp.si_su,
2630 			    tmp.su_len, hbuf, sizeof(hbuf), sbuf, sizeof(sbuf),
2631 			    NI_NUMERICHOST | NI_NUMERICSERV) == 0)
2632 				reply(0, "%s (|%d|%s|%s|)",
2633 				    ispassive ? "EPSV" : "EPRT",
2634 				    af, hbuf, sbuf);
2635 		}
2636 	} else
2637 		reply(0, "No data connection");
2638 
2639 	if (logged_in) {
2640 		reply(0,
2641 		    "Data sent:        " LLF " byte%s in " LLF " file%s",
2642 		    (LLT)total_data_out, PLURAL(total_data_out),
2643 		    (LLT)total_files_out, PLURAL(total_files_out));
2644 		reply(0,
2645 		    "Data received:    " LLF " byte%s in " LLF " file%s",
2646 		    (LLT)total_data_in, PLURAL(total_data_in),
2647 		    (LLT)total_files_in, PLURAL(total_files_in));
2648 		reply(0,
2649 		    "Total data:       " LLF " byte%s in " LLF " file%s",
2650 		    (LLT)total_data, PLURAL(total_data),
2651 		    (LLT)total_files, PLURAL(total_files));
2652 	}
2653 	otbi = total_bytes_in;
2654 	otbo = total_bytes_out;
2655 	otb = total_bytes;
2656 	reply(0, "Traffic sent:     " LLF " byte%s in " LLF " transfer%s",
2657 	    (LLT)otbo, PLURAL(otbo),
2658 	    (LLT)total_xfers_out, PLURAL(total_xfers_out));
2659 	reply(0, "Traffic received: " LLF " byte%s in " LLF " transfer%s",
2660 	    (LLT)otbi, PLURAL(otbi),
2661 	    (LLT)total_xfers_in, PLURAL(total_xfers_in));
2662 	reply(0, "Total traffic:    " LLF " byte%s in " LLF " transfer%s",
2663 	    (LLT)otb, PLURAL(otb),
2664 	    (LLT)total_xfers, PLURAL(total_xfers));
2665 
2666 	if (logged_in && !CURCLASS_FLAGS_ISSET(private)) {
2667 		struct ftpconv *cp;
2668 
2669 		reply(0, "%s", "");
2670 		reply(0, "Class: %s, type: %s",
2671 		    curclass.classname, CURCLASSTYPE);
2672 		reply(0, "Check PORT/LPRT commands: %sabled",
2673 		    CURCLASS_FLAGS_ISSET(checkportcmd) ? "en" : "dis");
2674 		if (! EMPTYSTR(curclass.display))
2675 			reply(0, "Display file: %s", curclass.display);
2676 		if (! EMPTYSTR(curclass.notify))
2677 			reply(0, "Notify fileglob: %s", curclass.notify);
2678 		reply(0, "Idle timeout: " LLF ", maximum timeout: " LLF,
2679 		    (LLT)curclass.timeout, (LLT)curclass.maxtimeout);
2680 		reply(0, "Current connections: %d", connections);
2681 		if (curclass.limit == -1)
2682 			reply(0, "Maximum connections: unlimited");
2683 		else
2684 			reply(0, "Maximum connections: " LLF,
2685 			    (LLT)curclass.limit);
2686 		if (curclass.limitfile)
2687 			reply(0, "Connection limit exceeded message file: %s",
2688 			    conffilename(curclass.limitfile));
2689 		if (! EMPTYSTR(curclass.chroot))
2690 			reply(0, "Chroot format: %s", curclass.chroot);
2691 		reply(0, "Deny bad ftpusers(5) quickly: %sabled",
2692 		    CURCLASS_FLAGS_ISSET(denyquick) ? "en" : "dis");
2693 		if (! EMPTYSTR(curclass.homedir))
2694 			reply(0, "Homedir format: %s", curclass.homedir);
2695 		if (curclass.maxfilesize == -1)
2696 			reply(0, "Maximum file size: unlimited");
2697 		else
2698 			reply(0, "Maximum file size: " LLF,
2699 			    (LLT)curclass.maxfilesize);
2700 		if (! EMPTYSTR(curclass.motd))
2701 			reply(0, "MotD file: %s", conffilename(curclass.motd));
2702 		reply(0,
2703 	    "Modify commands (CHMOD, DELE, MKD, RMD, RNFR, UMASK): %sabled",
2704 		    CURCLASS_FLAGS_ISSET(modify) ? "en" : "dis");
2705 		reply(0, "Upload commands (APPE, STOR, STOU): %sabled",
2706 		    CURCLASS_FLAGS_ISSET(upload) ? "en" : "dis");
2707 		reply(0, "Sanitize file names: %sabled",
2708 		    CURCLASS_FLAGS_ISSET(sanenames) ? "en" : "dis");
2709 		reply(0, "PASV/LPSV/EPSV connections: %sabled",
2710 		    CURCLASS_FLAGS_ISSET(passive) ? "en" : "dis");
2711 		if (curclass.advertise.su_len != 0) {
2712 			char buf[50];	/* big enough for IPv6 address */
2713 			const char *bp;
2714 
2715 			bp = inet_ntop(curclass.advertise.su_family,
2716 			    (void *)&curclass.advertise.su_addr,
2717 			    buf, sizeof(buf));
2718 			if (bp != NULL)
2719 				reply(0, "PASV advertise address: %s", bp);
2720 		}
2721 		if (curclass.portmin && curclass.portmax)
2722 			reply(0, "PASV port range: " LLF " - " LLF,
2723 			    (LLT)curclass.portmin, (LLT)curclass.portmax);
2724 		if (curclass.rateget)
2725 			reply(0, "Rate get limit: " LLF " bytes/sec",
2726 			    (LLT)curclass.rateget);
2727 		else
2728 			reply(0, "Rate get limit: disabled");
2729 		if (curclass.rateput)
2730 			reply(0, "Rate put limit: " LLF " bytes/sec",
2731 			    (LLT)curclass.rateput);
2732 		else
2733 			reply(0, "Rate put limit: disabled");
2734 		if (curclass.mmapsize)
2735 			reply(0, "Mmap size: " LLF, (LLT)curclass.mmapsize);
2736 		else
2737 			reply(0, "Mmap size: disabled");
2738 		if (curclass.readsize)
2739 			reply(0, "Read size: " LLF, (LLT)curclass.readsize);
2740 		else
2741 			reply(0, "Read size: default");
2742 		if (curclass.writesize)
2743 			reply(0, "Write size: " LLF, (LLT)curclass.writesize);
2744 		else
2745 			reply(0, "Write size: default");
2746 		if (curclass.recvbufsize)
2747 			reply(0, "Receive buffer size: " LLF,
2748 			    (LLT)curclass.recvbufsize);
2749 		else
2750 			reply(0, "Receive buffer size: default");
2751 		if (curclass.sendbufsize)
2752 			reply(0, "Send buffer size: " LLF,
2753 			    (LLT)curclass.sendbufsize);
2754 		else
2755 			reply(0, "Send buffer size: default");
2756 		if (curclass.sendlowat)
2757 			reply(0, "Send low water mark: " LLF,
2758 			    (LLT)curclass.sendlowat);
2759 		else
2760 			reply(0, "Send low water mark: default");
2761 		reply(0, "Umask: %.04o", curclass.umask);
2762 		for (cp = curclass.conversions; cp != NULL; cp=cp->next) {
2763 			if (cp->suffix == NULL || cp->types == NULL ||
2764 			    cp->command == NULL)
2765 				continue;
2766 			reply(0, "Conversion: %s [%s] disable: %s, command: %s",
2767 			    cp->suffix, cp->types, cp->disable, cp->command);
2768 		}
2769 	}
2770 
2771 	reply(211, "End of status");
2772 }
2773 
2774 void
2775 fatal(const char *s)
2776 {
2777 
2778 	reply(451, "Error in server: %s\n", s);
2779 	reply(221, "Closing connection due to server error.");
2780 	dologout(0);
2781 	/* NOTREACHED */
2782 }
2783 
2784 /*
2785  * reply() --
2786  *	depending on the value of n, display fmt with a trailing CRLF and
2787  *	prefix of:
2788  *	n < -1		prefix the message with abs(n) + "-"	(initial line)
2789  *	n == 0		prefix the message with 4 spaces	(middle lines)
2790  *	n >  0		prefix the message with n + " "		(final line)
2791  */
2792 void
2793 reply(int n, const char *fmt, ...)
2794 {
2795 	char	msg[MAXPATHLEN * 2 + 100];
2796 	size_t	b;
2797 	va_list	ap;
2798 
2799 	b = 0;
2800 	if (n == 0)
2801 		b = snprintf(msg, sizeof(msg), "    ");
2802 	else if (n < 0)
2803 		b = snprintf(msg, sizeof(msg), "%d-", -n);
2804 	else
2805 		b = snprintf(msg, sizeof(msg), "%d ", n);
2806 	va_start(ap, fmt);
2807 	vsnprintf(msg + b, sizeof(msg) - b, fmt, ap);
2808 	va_end(ap);
2809 	cprintf(stdout, "%s\r\n", msg);
2810 	(void)fflush(stdout);
2811 	if (ftpd_debug)
2812 		syslog(LOG_DEBUG, "<--- %s", msg);
2813 }
2814 
2815 static void
2816 logremotehost(struct sockinet *who)
2817 {
2818 
2819 	if (getnameinfo((struct sockaddr *)&who->si_su,
2820 	    who->su_len, remotehost, sizeof(remotehost), NULL, 0,
2821 	    getnameopts))
2822 		strlcpy(remotehost, "?", sizeof(remotehost));
2823 
2824 #if defined(HAVE_SETPROCTITLE)
2825 	snprintf(proctitle, sizeof(proctitle), "%s: connected", remotehost);
2826 	setproctitle("%s", proctitle);
2827 #endif /* defined(HAVE_SETPROCTITLE) */
2828 	if (logging)
2829 		syslog(LOG_INFO, "connection from %s to %s",
2830 		    remotehost, hostname);
2831 }
2832 
2833 /*
2834  * Record logout in wtmp file and exit with supplied status.
2835  * NOTE: because this is called from signal handlers it cannot
2836  *       use stdio (or call other functions that use stdio).
2837  */
2838 void
2839 dologout(int status)
2840 {
2841 	/*
2842 	* Prevent reception of SIGURG from resulting in a resumption
2843 	* back to the main program loop.
2844 	*/
2845 	transflag = 0;
2846 	logout_utmp();
2847 	if (logged_in) {
2848 #ifdef KERBEROS
2849 		if (!notickets && krbtkfile_env)
2850 			unlink(krbtkfile_env);
2851 #endif
2852 	}
2853 	/* beware of flushing buffers after a SIGPIPE */
2854 	if (xferlogfd != -1)
2855 		close(xferlogfd);
2856 	_exit(status);
2857 }
2858 
2859 void
2860 abor(void)
2861 {
2862 
2863 	if (!transflag)
2864 		return;
2865 	tmpline[0] = '\0';
2866 	is_oob = 0;
2867 	reply(426, "Transfer aborted. Data connection closed.");
2868 	reply(226, "Abort successful");
2869 	transflag = 0;		/* flag that the transfer has aborted */
2870 }
2871 
2872 void
2873 statxfer(void)
2874 {
2875 
2876 	if (!transflag)
2877 		return;
2878 	tmpline[0] = '\0';
2879 	is_oob = 0;
2880 	if (file_size != (off_t) -1)
2881 		reply(213,
2882 		    "Status: " LLF " of " LLF " byte%s transferred",
2883 		    (LLT)byte_count, (LLT)file_size,
2884 		    PLURAL(byte_count));
2885 	else
2886 		reply(213, "Status: " LLF " byte%s transferred",
2887 		    (LLT)byte_count, PLURAL(byte_count));
2888 }
2889 
2890 /*
2891  * Call when urgflag != 0 to handle Out Of Band commands.
2892  * Returns non zero if the OOB command aborted the transfer
2893  * by setting transflag to 0. (c.f., "ABOR").
2894  */
2895 static int
2896 handleoobcmd()
2897 {
2898 	char *cp;
2899 
2900 	if (!urgflag)
2901 		return (0);
2902 	urgflag = 0;
2903 	/* only process if transfer occurring */
2904 	if (!transflag)
2905 		return (0);
2906 	cp = tmpline;
2907 	if (getline(cp, sizeof(tmpline), stdin) == NULL) {
2908 		reply(221, "You could at least say goodbye.");
2909 		dologout(0);
2910 	}
2911 		/*
2912 		 * Manually parse OOB commands, because we can't
2913 		 * recursively call the yacc parser...
2914 		 */
2915 	if (strcasecmp(cp, "ABOR\r\n") == 0) {
2916 		abor();
2917 	} else if (strcasecmp(cp, "STAT\r\n") == 0) {
2918 		statxfer();
2919 	} else {
2920 		/* XXX: error with "500 unknown command" ? */
2921 	}
2922 	return (transflag == 0);
2923 }
2924 
2925 static int
2926 bind_pasv_addr(void)
2927 {
2928 	static int passiveport;
2929 	int port, len;
2930 
2931 	len = pasv_addr.su_len;
2932 	if (curclass.portmin == 0 && curclass.portmax == 0) {
2933 		pasv_addr.su_port = 0;
2934 		return (bind(pdata, (struct sockaddr *)&pasv_addr.si_su, len));
2935 	}
2936 
2937 	if (passiveport == 0) {
2938 		srand(getpid());
2939 		passiveport = rand() % (curclass.portmax - curclass.portmin)
2940 		    + curclass.portmin;
2941 	}
2942 
2943 	port = passiveport;
2944 	while (1) {
2945 		port++;
2946 		if (port > curclass.portmax)
2947 			port = curclass.portmin;
2948 		else if (port == passiveport) {
2949 			errno = EAGAIN;
2950 			return (-1);
2951 		}
2952 		pasv_addr.su_port = htons(port);
2953 		if (bind(pdata, (struct sockaddr *)&pasv_addr.si_su, len) == 0)
2954 			break;
2955 		if (errno != EADDRINUSE)
2956 			return (-1);
2957 	}
2958 	passiveport = port;
2959 	return (0);
2960 }
2961 
2962 /*
2963  * Note: a response of 425 is not mentioned as a possible response to
2964  *	the PASV command in RFC959. However, it has been blessed as
2965  *	a legitimate response by Jon Postel in a telephone conversation
2966  *	with Rick Adams on 25 Jan 89.
2967  */
2968 void
2969 passive(void)
2970 {
2971 	socklen_t len, recvbufsize;
2972 	char *p, *a;
2973 
2974 	if (pdata >= 0)
2975 		close(pdata);
2976 	pdata = socket(AF_INET, SOCK_STREAM, 0);
2977 	if (pdata < 0 || !logged_in) {
2978 		perror_reply(425, "Can't open passive connection");
2979 		return;
2980 	}
2981 	pasv_addr = ctrl_addr;
2982 
2983 	if (bind_pasv_addr() < 0)
2984 		goto pasv_error;
2985 	len = pasv_addr.su_len;
2986 	if (getsockname(pdata, (struct sockaddr *) &pasv_addr.si_su, &len) < 0)
2987 		goto pasv_error;
2988 	pasv_addr.su_len = len;
2989 	if (curclass.recvbufsize) {
2990 		recvbufsize = curclass.recvbufsize;
2991 		if (setsockopt(pdata, SOL_SOCKET, SO_RCVBUF, &recvbufsize,
2992 			       sizeof(int)) == -1)
2993 			syslog(LOG_WARNING, "setsockopt(SO_RCVBUF, %d): %m",
2994 			       recvbufsize);
2995 	}
2996 	if (listen(pdata, 1) < 0)
2997 		goto pasv_error;
2998 	if (curclass.advertise.su_len != 0)
2999 		a = (char *) &curclass.advertise.su_addr;
3000 	else
3001 		a = (char *) &pasv_addr.su_addr;
3002 	p = (char *) &pasv_addr.su_port;
3003 
3004 #define UC(b) (((int) b) & 0xff)
3005 
3006 	reply(227, "Entering Passive Mode (%d,%d,%d,%d,%d,%d)", UC(a[0]),
3007 		UC(a[1]), UC(a[2]), UC(a[3]), UC(p[0]), UC(p[1]));
3008 	return;
3009 
3010  pasv_error:
3011 	(void) close(pdata);
3012 	pdata = -1;
3013 	perror_reply(425, "Can't open passive connection");
3014 	return;
3015 }
3016 
3017 /*
3018  * convert protocol identifier to/from AF
3019  */
3020 int
3021 lpsvproto2af(int proto)
3022 {
3023 
3024 	switch (proto) {
3025 	case 4:
3026 		return AF_INET;
3027 #ifdef INET6
3028 	case 6:
3029 		return AF_INET6;
3030 #endif
3031 	default:
3032 		return -1;
3033 	}
3034 }
3035 
3036 int
3037 af2lpsvproto(int af)
3038 {
3039 
3040 	switch (af) {
3041 	case AF_INET:
3042 		return 4;
3043 #ifdef INET6
3044 	case AF_INET6:
3045 		return 6;
3046 #endif
3047 	default:
3048 		return -1;
3049 	}
3050 }
3051 
3052 int
3053 epsvproto2af(int proto)
3054 {
3055 
3056 	switch (proto) {
3057 	case 1:
3058 		return AF_INET;
3059 #ifdef INET6
3060 	case 2:
3061 		return AF_INET6;
3062 #endif
3063 	default:
3064 		return -1;
3065 	}
3066 }
3067 
3068 int
3069 af2epsvproto(int af)
3070 {
3071 
3072 	switch (af) {
3073 	case AF_INET:
3074 		return 1;
3075 #ifdef INET6
3076 	case AF_INET6:
3077 		return 2;
3078 #endif
3079 	default:
3080 		return -1;
3081 	}
3082 }
3083 
3084 /*
3085  * 228 Entering Long Passive Mode (af, hal, h1, h2, h3,..., pal, p1, p2...)
3086  * 229 Entering Extended Passive Mode (|||port|)
3087  */
3088 void
3089 long_passive(char *cmd, int pf)
3090 {
3091 	socklen_t len;
3092 	char *p, *a;
3093 
3094 	if (!logged_in) {
3095 		syslog(LOG_NOTICE, "long passive but not logged in");
3096 		reply(503, "Login with USER first.");
3097 		return;
3098 	}
3099 
3100 	if (pf != PF_UNSPEC && ctrl_addr.su_family != pf) {
3101 		/*
3102 		 * XXX: only EPRT/EPSV ready clients will understand this
3103 		 */
3104 		if (strcmp(cmd, "EPSV") != 0)
3105 			reply(501, "Network protocol mismatch"); /*XXX*/
3106 		else
3107 			epsv_protounsupp("Network protocol mismatch");
3108 
3109 		return;
3110 	}
3111 
3112 	if (pdata >= 0)
3113 		close(pdata);
3114 	pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
3115 	if (pdata < 0) {
3116 		perror_reply(425, "Can't open passive connection");
3117 		return;
3118 	}
3119 	pasv_addr = ctrl_addr;
3120 	if (bind_pasv_addr() < 0)
3121 		goto pasv_error;
3122 	len = pasv_addr.su_len;
3123 	if (getsockname(pdata, (struct sockaddr *) &pasv_addr.si_su, &len) < 0)
3124 		goto pasv_error;
3125 	pasv_addr.su_len = len;
3126 	if (listen(pdata, 1) < 0)
3127 		goto pasv_error;
3128 	p = (char *) &pasv_addr.su_port;
3129 
3130 #define UC(b) (((int) b) & 0xff)
3131 
3132 	if (strcmp(cmd, "LPSV") == 0) {
3133 		struct sockinet *advert;
3134 
3135 		if (curclass.advertise.su_len != 0)
3136 			advert = &curclass.advertise;
3137 		else
3138 			advert = &pasv_addr;
3139 		switch (advert->su_family) {
3140 		case AF_INET:
3141 			a = (char *) &advert->su_addr;
3142 			reply(228,
3143     "Entering Long Passive Mode (%d,%d,%d,%d,%d,%d,%d,%d,%d)",
3144 				4, 4, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
3145 				2, UC(p[0]), UC(p[1]));
3146 			return;
3147 #ifdef INET6
3148 		case AF_INET6:
3149 			a = (char *) &advert->su_6addr;
3150 			reply(228,
3151     "Entering Long Passive Mode (%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d)",
3152 				6, 16,
3153 				UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
3154 				UC(a[4]), UC(a[5]), UC(a[6]), UC(a[7]),
3155 				UC(a[8]), UC(a[9]), UC(a[10]), UC(a[11]),
3156 				UC(a[12]), UC(a[13]), UC(a[14]), UC(a[15]),
3157 				2, UC(p[0]), UC(p[1]));
3158 			return;
3159 #endif
3160 		}
3161 #undef UC
3162 	} else if (strcmp(cmd, "EPSV") == 0) {
3163 		switch (pasv_addr.su_family) {
3164 		case AF_INET:
3165 #ifdef INET6
3166 		case AF_INET6:
3167 #endif
3168 			reply(229, "Entering Extended Passive Mode (|||%d|)",
3169 			    ntohs(pasv_addr.su_port));
3170 			return;
3171 		}
3172 	} else {
3173 		/* more proper error code? */
3174 	}
3175 
3176  pasv_error:
3177 	(void) close(pdata);
3178 	pdata = -1;
3179 	perror_reply(425, "Can't open passive connection");
3180 	return;
3181 }
3182 
3183 int
3184 extended_port(const char *arg)
3185 {
3186 	char *tmp = NULL;
3187 	char *result[3];
3188 	char *p, *q;
3189 	char delim;
3190 	struct addrinfo hints;
3191 	struct addrinfo *res = NULL;
3192 	int i;
3193 	unsigned long proto;
3194 
3195 	tmp = ftpd_strdup(arg);
3196 	p = tmp;
3197 	delim = p[0];
3198 	p++;
3199 	memset(result, 0, sizeof(result));
3200 	for (i = 0; i < 3; i++) {
3201 		q = strchr(p, delim);
3202 		if (!q || *q != delim)
3203 			goto parsefail;
3204 		*q++ = '\0';
3205 		result[i] = p;
3206 		p = q;
3207 	}
3208 
3209 			/* some more sanity checks */
3210 	errno = 0;
3211 	p = NULL;
3212 	(void)strtoul(result[2], &p, 10);
3213 	if (errno || !*result[2] || *p)
3214 		goto parsefail;
3215 	errno = 0;
3216 	p = NULL;
3217 	proto = strtoul(result[0], &p, 10);
3218 	if (errno || !*result[0] || *p)
3219 		goto protounsupp;
3220 
3221 	memset(&hints, 0, sizeof(hints));
3222 	hints.ai_family = epsvproto2af((int)proto);
3223 	if (hints.ai_family < 0)
3224 		goto protounsupp;
3225 	hints.ai_socktype = SOCK_STREAM;
3226 	hints.ai_flags = AI_NUMERICHOST;
3227 	if (getaddrinfo(result[1], result[2], &hints, &res))
3228 		goto parsefail;
3229 	if (res->ai_next)
3230 		goto parsefail;
3231 	if (sizeof(data_dest) < res->ai_addrlen)
3232 		goto parsefail;
3233 	memcpy(&data_dest.si_su, res->ai_addr, res->ai_addrlen);
3234 	data_dest.su_len = res->ai_addrlen;
3235 #ifdef INET6
3236 	if (his_addr.su_family == AF_INET6 &&
3237 	    data_dest.su_family == AF_INET6) {
3238 			/* XXX: more sanity checks! */
3239 		data_dest.su_scope_id = his_addr.su_scope_id;
3240 	}
3241 #endif
3242 
3243 	if (tmp != NULL)
3244 		free(tmp);
3245 	if (res)
3246 		freeaddrinfo(res);
3247 	return 0;
3248 
3249  parsefail:
3250 	reply(500, "Invalid argument, rejected.");
3251 	usedefault = 1;
3252 	if (tmp != NULL)
3253 		free(tmp);
3254 	if (res)
3255 		freeaddrinfo(res);
3256 	return -1;
3257 
3258  protounsupp:
3259 	epsv_protounsupp("Protocol not supported");
3260 	usedefault = 1;
3261 	if (tmp != NULL)
3262 		free(tmp);
3263 	return -1;
3264 }
3265 
3266 /*
3267  * 522 Protocol not supported (proto,...)
3268  * as we assume address family for control and data connections are the same,
3269  * we do not return the list of address families we support - instead, we
3270  * return the address family of the control connection.
3271  */
3272 void
3273 epsv_protounsupp(const char *message)
3274 {
3275 	int proto;
3276 
3277 	proto = af2epsvproto(ctrl_addr.su_family);
3278 	if (proto < 0)
3279 		reply(501, "%s", message);	/* XXX */
3280 	else
3281 		reply(522, "%s, use (%d)", message, proto);
3282 }
3283 
3284 /*
3285  * Generate unique name for file with basename "local".
3286  * The file named "local" is already known to exist.
3287  * Generates failure reply on error.
3288  *
3289  * XXX:	this function should under go changes similar to
3290  *	the mktemp(3)/mkstemp(3) changes.
3291  */
3292 static char *
3293 gunique(const char *local)
3294 {
3295 	static char new[MAXPATHLEN];
3296 	struct stat st;
3297 	char *cp;
3298 	int count;
3299 
3300 	cp = strrchr(local, '/');
3301 	if (cp)
3302 		*cp = '\0';
3303 	if (stat(cp ? local : ".", &st) < 0) {
3304 		perror_reply(553, cp ? local : ".");
3305 		return (NULL);
3306 	}
3307 	if (cp)
3308 		*cp = '/';
3309 	for (count = 1; count < 100; count++) {
3310 		(void)snprintf(new, sizeof(new) - 1, "%s.%d", local, count);
3311 		if (stat(new, &st) < 0)
3312 			return (new);
3313 	}
3314 	reply(452, "Unique file name cannot be created.");
3315 	return (NULL);
3316 }
3317 
3318 /*
3319  * Format and send reply containing system error number.
3320  */
3321 void
3322 perror_reply(int code, const char *string)
3323 {
3324 	int save_errno;
3325 
3326 	save_errno = errno;
3327 	reply(code, "%s: %s.", string, strerror(errno));
3328 	errno = save_errno;
3329 }
3330 
3331 static char *onefile[] = {
3332 	"",
3333 	0
3334 };
3335 
3336 void
3337 send_file_list(const char *whichf)
3338 {
3339 	struct stat st;
3340 	DIR *dirp;
3341 	struct dirent *dir;
3342 	FILE *volatile dout;
3343 	char **volatile dirlist;
3344 	char *dirname, *p;
3345 	char *notglob;
3346 	int volatile simple;
3347 	int volatile freeglob;
3348 	glob_t gl;
3349 
3350 	dirp = NULL;
3351 	dout = NULL;
3352 	notglob = NULL;
3353 	simple = 0;
3354 	freeglob = 0;
3355 	urgflag = 0;
3356 
3357 	p = NULL;
3358 	if (strpbrk(whichf, "~{[*?") != NULL) {
3359 		int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE|GLOB_LIMIT;
3360 
3361 		memset(&gl, 0, sizeof(gl));
3362 		freeglob = 1;
3363 		if (glob(whichf, flags, 0, &gl)) {
3364 			reply(450, "Not found");
3365 			goto cleanup_send_file_list;
3366 		} else if (gl.gl_pathc == 0) {
3367 			errno = ENOENT;
3368 			perror_reply(450, whichf);
3369 			goto cleanup_send_file_list;
3370 		}
3371 		dirlist = gl.gl_pathv;
3372 	} else {
3373 		notglob = ftpd_strdup(whichf);
3374 		onefile[0] = notglob;
3375 		dirlist = onefile;
3376 		simple = 1;
3377 	}
3378 					/* XXX: } for vi sm */
3379 
3380 	while ((dirname = *dirlist++) != NULL) {
3381 		int trailingslash = 0;
3382 
3383 		if (stat(dirname, &st) < 0) {
3384 			/*
3385 			 * If user typed "ls -l", etc, and the client
3386 			 * used NLST, do what the user meant.
3387 			 */
3388 			/* XXX: nuke this support? */
3389 			if (dirname[0] == '-' && *dirlist == NULL &&
3390 			    transflag == 0) {
3391 				char *argv[] = { INTERNAL_LS, "", NULL };
3392 
3393 				argv[1] = dirname;
3394 				retrieve(argv, dirname);
3395 				goto cleanup_send_file_list;
3396 			}
3397 			perror_reply(450, whichf);
3398 			goto cleanup_send_file_list;
3399 		}
3400 
3401 		if (S_ISREG(st.st_mode)) {
3402 			/*
3403 			 * XXXRFC:
3404 			 *	should we follow RFC959 and not work
3405 			 *	for non directories?
3406 			 */
3407 			if (dout == NULL) {
3408 				dout = dataconn("file list", (off_t)-1, "w");
3409 				if (dout == NULL)
3410 					goto cleanup_send_file_list;
3411 				transflag = 1;
3412 			}
3413 			cprintf(dout, "%s%s\n", dirname,
3414 			    type == TYPE_A ? "\r" : "");
3415 			continue;
3416 		} else if (!S_ISDIR(st.st_mode))
3417 			continue;
3418 
3419 		if (dirname[strlen(dirname) - 1] == '/')
3420 			trailingslash++;
3421 
3422 		if ((dirp = opendir(dirname)) == NULL)
3423 			continue;
3424 
3425 		while ((dir = readdir(dirp)) != NULL) {
3426 			char nbuf[MAXPATHLEN];
3427 
3428 			if (urgflag && handleoobcmd())
3429 				goto cleanup_send_file_list;
3430 
3431 			if (ISDOTDIR(dir->d_name) || ISDOTDOTDIR(dir->d_name))
3432 				continue;
3433 
3434 			(void)snprintf(nbuf, sizeof(nbuf), "%s%s%s", dirname,
3435 			    trailingslash ? "" : "/", dir->d_name);
3436 
3437 			/*
3438 			 * We have to do a stat to ensure it's
3439 			 * not a directory or special file.
3440 			 */
3441 			/*
3442 			 * XXXRFC:
3443 			 *	should we follow RFC959 and filter out
3444 			 *	non files ?   lukem - NO!, or not until
3445 			 *	our ftp client uses MLS{T,D} for completion.
3446 			 */
3447 			if (simple || (stat(nbuf, &st) == 0 &&
3448 			    S_ISREG(st.st_mode))) {
3449 				if (dout == NULL) {
3450 					dout = dataconn("file list", (off_t)-1,
3451 						"w");
3452 					if (dout == NULL)
3453 						goto cleanup_send_file_list;
3454 					transflag = 1;
3455 				}
3456 				p = nbuf;
3457 				if (nbuf[0] == '.' && nbuf[1] == '/')
3458 					p = &nbuf[2];
3459 				cprintf(dout, "%s%s\n", p,
3460 				    type == TYPE_A ? "\r" : "");
3461 			}
3462 		}
3463 		(void) closedir(dirp);
3464 	}
3465 
3466 	if (dout == NULL)
3467 		reply(450, "No files found.");
3468 	else if (ferror(dout) != 0)
3469 		perror_reply(451, "Data connection");
3470 	else
3471 		reply(226, "Transfer complete.");
3472 
3473  cleanup_send_file_list:
3474 	closedataconn(dout);
3475 	transflag = 0;
3476 	urgflag = 0;
3477 	total_xfers++;
3478 	total_xfers_out++;
3479 	if (notglob)
3480 		free(notglob);
3481 	if (freeglob)
3482 		globfree(&gl);
3483 }
3484 
3485 char *
3486 conffilename(const char *s)
3487 {
3488 	static char filename[MAXPATHLEN];
3489 
3490 	if (*s == '/')
3491 		strlcpy(filename, s, sizeof(filename));
3492 	else
3493 		(void)snprintf(filename, sizeof(filename), "%s/%s", confdir ,s);
3494 	return (filename);
3495 }
3496 
3497 /*
3498  * logxfer --
3499  *	if logging > 1, then based on the arguments, syslog a message:
3500  *	 if bytes != -1		"<command> <file1> = <bytes> bytes"
3501  *	 else if file2 != NULL	"<command> <file1> <file2>"
3502  *	 else			"<command> <file1>"
3503  *	if elapsed != NULL, append "in xxx.yyy seconds"
3504  *	if error != NULL, append ": " + error
3505  *
3506  *	if doxferlog != 0, bytes != -1, and command is "get", "put",
3507  *	or "append", syslog and/or write a wu-ftpd style xferlog entry
3508  */
3509 void
3510 logxfer(const char *command, off_t bytes, const char *file1, const char *file2,
3511     const struct timeval *elapsed, const char *error)
3512 {
3513 	char		 buf[MAXPATHLEN * 2 + 100];
3514 	char		 realfile1[MAXPATHLEN], realfile2[MAXPATHLEN];
3515 	const char	*r1, *r2;
3516 	char		 direction;
3517 	size_t		 len;
3518 	time_t		 now;
3519 
3520 	if (logging <=1 && !doxferlog)
3521 		return;
3522 
3523 	r1 = r2 = NULL;
3524 	if ((r1 = realpath(file1, realfile1)) == NULL)
3525 		r1 = file1;
3526 	if (file2 != NULL)
3527 		if ((r2 = realpath(file2, realfile2)) == NULL)
3528 			r2 = file2;
3529 
3530 		/*
3531 		 * syslog command
3532 		 */
3533 	if (logging > 1) {
3534 		len = snprintf(buf, sizeof(buf), "%s %s", command, r1);
3535 		if (bytes != (off_t)-1)
3536 			len += snprintf(buf + len, sizeof(buf) - len,
3537 			    " = " LLF " byte%s", (LLT) bytes, PLURAL(bytes));
3538 		else if (r2 != NULL)
3539 			len += snprintf(buf + len, sizeof(buf) - len,
3540 			    " %s", r2);
3541 		if (elapsed != NULL)
3542 			len += snprintf(buf + len, sizeof(buf) - len,
3543 			    " in %ld.%.03d seconds", elapsed->tv_sec,
3544 			    (int)(elapsed->tv_usec / 1000));
3545 		if (error != NULL)
3546 			len += snprintf(buf + len, sizeof(buf) - len,
3547 			    ": %s", error);
3548 		syslog(LOG_INFO, "%s", buf);
3549 	}
3550 
3551 		/*
3552 		 * syslog wu-ftpd style log entry, prefixed with "xferlog: "
3553 		 */
3554 	if (!doxferlog || bytes == -1)
3555 		return;
3556 
3557 	if (strcmp(command, "get") == 0)
3558 		direction = 'o';
3559 	else if (strcmp(command, "put") == 0 || strcmp(command, "append") == 0)
3560 		direction = 'i';
3561 	else
3562 		return;
3563 
3564 	time(&now);
3565 	len = snprintf(buf, sizeof(buf),
3566 	    "%.24s %ld %s " LLF " %s %c %s %c %c %s FTP 0 * %c\n",
3567 
3568 /*
3569  * XXX: wu-ftpd puts ' (send)' or ' (recv)' in the syslog message, and removes
3570  *	the full date.  This may be problematic for accurate log parsing,
3571  *	given that syslog messages don't contain the full date.
3572  */
3573 	    ctime(&now),
3574 	    elapsed == NULL ? 0 : elapsed->tv_sec + (elapsed->tv_usec > 0),
3575 	    remotehost,
3576 	    (LLT) bytes,
3577 	    r1,
3578 	    type == TYPE_A ? 'a' : 'b',
3579 	    "_",		/* XXX: take conversions into account? */
3580 	    direction,
3581 
3582 	    curclass.type == CLASS_GUEST ?  'a' :
3583 	    curclass.type == CLASS_CHROOT ? 'g' :
3584 	    curclass.type == CLASS_REAL ?   'r' : '?',
3585 
3586 	    curclass.type == CLASS_GUEST ? pw->pw_passwd : pw->pw_name,
3587 	    error != NULL ? 'i' : 'c'
3588 	    );
3589 
3590 	if ((doxferlog & 2) && xferlogfd != -1)
3591 		write(xferlogfd, buf, len);
3592 	if ((doxferlog & 1)) {
3593 		buf[len-1] = '\n';	/* strip \n from syslog message */
3594 		syslog(LOG_INFO, "xferlog: %s", buf);
3595 	}
3596 }
3597 
3598 /*
3599  * Log the resource usage.
3600  *
3601  * XXX: more resource usage to logging?
3602  */
3603 void
3604 logrusage(const struct rusage *rusage_before,
3605     const struct rusage *rusage_after)
3606 {
3607 	struct timeval usrtime, systime;
3608 
3609 	if (logging <= 1)
3610 		return;
3611 
3612 	timersub(&rusage_after->ru_utime, &rusage_before->ru_utime, &usrtime);
3613 	timersub(&rusage_after->ru_stime, &rusage_before->ru_stime, &systime);
3614 	syslog(LOG_INFO, "%ld.%.03du %ld.%.03ds %ld+%ldio %ldpf+%ldw",
3615 	    usrtime.tv_sec, (int)(usrtime.tv_usec / 1000),
3616 	    systime.tv_sec, (int)(systime.tv_usec / 1000),
3617 	    rusage_after->ru_inblock - rusage_before->ru_inblock,
3618 	    rusage_after->ru_oublock - rusage_before->ru_oublock,
3619 	    rusage_after->ru_majflt - rusage_before->ru_majflt,
3620 	    rusage_after->ru_nswap - rusage_before->ru_nswap);
3621 }
3622 
3623 /*
3624  * Determine if `password' is valid for user given in `pw'.
3625  * Returns 2 if password expired, 1 if otherwise failed, 0 if ok
3626  */
3627 int
3628 checkpassword(const struct passwd *pwent, const char *password)
3629 {
3630 	char	*orig, *new;
3631 	time_t	 change, expire, now;
3632 
3633 	change = expire = 0;
3634 	if (pwent == NULL)
3635 		return 1;
3636 
3637 	time(&now);
3638 	orig = pwent->pw_passwd;	/* save existing password */
3639 	expire = pwent->pw_expire;
3640 	change = (pwent->pw_change == _PASSWORD_CHGNOW)? now : pwent->pw_change;
3641 
3642 	if (orig[0] == '\0')		/* don't allow empty passwords */
3643 		return 1;
3644 
3645 	new = crypt(password, orig);	/* encrypt given password */
3646 	if (strcmp(new, orig) != 0)	/* compare */
3647 		return 1;
3648 
3649 	if ((expire && now >= expire) || (change && now >= change))
3650 		return 2;		/* check if expired */
3651 
3652 	return 0;			/* OK! */
3653 }
3654 
3655 char *
3656 ftpd_strdup(const char *s)
3657 {
3658 	char *new = strdup(s);
3659 
3660 	if (new == NULL)
3661 		fatal("Local resource failure: malloc");
3662 		/* NOTREACHED */
3663 	return (new);
3664 }
3665 
3666 /*
3667  * As per fprintf(), but increment total_bytes and total_bytes_out,
3668  * by the appropriate amount.
3669  */
3670 void
3671 cprintf(FILE *fd, const char *fmt, ...)
3672 {
3673 	off_t b;
3674 	va_list ap;
3675 
3676 	va_start(ap, fmt);
3677 	b = vfprintf(fd, fmt, ap);
3678 	va_end(ap);
3679 	total_bytes += b;
3680 	total_bytes_out += b;
3681 }
3682 
3683 #ifdef USE_PAM
3684 /*
3685  * the following code is stolen from imap-uw PAM authentication module and
3686  * login.c
3687  */
3688 typedef struct {
3689 	const char *uname;	/* user name */
3690 	int	    triedonce;	/* if non-zero, tried before */
3691 } ftpd_cred_t;
3692 
3693 static int
3694 auth_conv(int num_msg, const struct pam_message **msg,
3695     struct pam_response **resp, void *appdata)
3696 {
3697 	int i;
3698 	size_t n;
3699 	ftpd_cred_t *cred = (ftpd_cred_t *) appdata;
3700 	struct pam_response *myreply;
3701 	char pbuf[FTP_BUFLEN];
3702 
3703 	if (num_msg <= 0 || num_msg > PAM_MAX_NUM_MSG)
3704 		return (PAM_CONV_ERR);
3705 	myreply = calloc(num_msg, sizeof *myreply);
3706 	if (myreply == NULL)
3707 		return PAM_BUF_ERR;
3708 
3709 	for (i = 0; i < num_msg; i++) {
3710 		myreply[i].resp_retcode = 0;
3711 		myreply[i].resp = NULL;
3712 		switch (msg[i]->msg_style) {
3713 		case PAM_PROMPT_ECHO_ON:	/* user */
3714 			myreply[i].resp = ftpd_strdup(cred->uname);
3715 			/* PAM frees resp. */
3716 			break;
3717 		case PAM_PROMPT_ECHO_OFF:	/* authtok (password) */
3718 				/*
3719 				 * Only send a single 331 reply and
3720 				 * then expect a PASS.
3721 				 */
3722 			if (cred->triedonce) {
3723 				syslog(LOG_ERR,
3724 			"auth_conv: already performed PAM_PROMPT_ECHO_OFF");
3725 				goto fail;
3726 			}
3727 			cred->triedonce++;
3728 			if (msg[i]->msg[0] == '\0') {
3729 				(void)strlcpy(pbuf, "password", sizeof(pbuf));
3730 			} else {
3731 				/* Uncapitalize msg, remove trailing ':' */
3732 				(void)strlcpy(pbuf, msg[i]->msg, sizeof(pbuf));
3733 				n = strlen(pbuf);
3734 				if (isupper((unsigned char)pbuf[0]))
3735 					pbuf[0] = tolower(
3736 					    (unsigned char)pbuf[0]);
3737 				n = strlen(pbuf) - 1;
3738 				if (pbuf[n] == ':')
3739 					pbuf[n] = '\0';
3740 			}
3741 				/* Send reply, wait for a response. */
3742 			reply(331, "User %s accepted, provide %s.",
3743 			    cred->uname, pbuf);
3744 			(void) alarm(curclass.timeout);
3745 			if (getline(pbuf, sizeof(pbuf)-1, stdin) == NULL) {
3746 				reply(221, "You could at least say goodbye.");
3747 				dologout(0);
3748 			}
3749 			(void) alarm(0);
3750 				/* Ensure it is PASS */
3751 			if (strncasecmp(pbuf, "PASS ", 5) != 0) {
3752 			    syslog(LOG_ERR,
3753 				"auth_conv: unexpected reply '%.4s'", pbuf);
3754 			    /* XXX: should we do this reply(-530, ..) ? */
3755 			    reply(-530, "Unexpected reply '%.4s'.", pbuf);
3756 			    goto fail;
3757 			}
3758 				/* Strip CRLF from "PASS" reply */
3759 			n = strlen(pbuf);
3760 			while (--n >= 5 &&
3761 			    (pbuf[n] == '\r' || pbuf[n] == '\n'))
3762 			    pbuf[n] = '\0';
3763 				/* Copy password into reply */
3764 			myreply[i].resp = ftpd_strdup(pbuf+5);
3765 				/* PAM frees resp. */
3766 			break;
3767 		case PAM_TEXT_INFO:
3768 		case PAM_ERROR_MSG:
3769 			break;
3770 		default:			/* unknown message style */
3771 			goto fail;
3772 		}
3773 	}
3774 
3775 	*resp = myreply;
3776 	return PAM_SUCCESS;
3777 
3778  fail:
3779 	free(myreply);
3780 	*resp = NULL;
3781 	return PAM_CONV_ERR;
3782 }
3783 
3784 /*
3785  * Attempt to authenticate the user using PAM.  Returns 0 if the user is
3786  * authenticated, or 1 if not authenticated.  If some sort of PAM system
3787  * error occurs (e.g., the "/etc/pam.conf" file is missing) then this
3788  * function returns -1.  This can be used as an indication that we should
3789  * fall back to a different authentication mechanism.
3790  * pw maybe be updated to a new user if PAM_USER changes from curname.
3791  */
3792 static int
3793 auth_pam(void)
3794 {
3795 	const char *tmpl_user;
3796 	const void *item;
3797 	int rval;
3798 	int e;
3799 	ftpd_cred_t auth_cred = { curname, 0 };
3800 	struct pam_conv conv = { &auth_conv, &auth_cred };
3801 
3802 	e = pam_start("ftpd", curname, &conv, &pamh);
3803 	if (e != PAM_SUCCESS) {
3804 		/*
3805 		 * In OpenPAM, it's OK to pass NULL to pam_strerror()
3806 		 * if context creation has failed in the first place.
3807 		 */
3808 		syslog(LOG_ERR, "pam_start: %s", pam_strerror(NULL, e));
3809 		return -1;
3810 	}
3811 
3812 	e = pam_set_item(pamh, PAM_RHOST, remotehost);
3813 	if (e != PAM_SUCCESS) {
3814 		syslog(LOG_ERR, "pam_set_item(PAM_RHOST): %s",
3815 			pam_strerror(pamh, e));
3816 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
3817 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
3818 		}
3819 		pamh = NULL;
3820 		return -1;
3821 	}
3822 
3823 	e = pam_set_item(pamh, PAM_SOCKADDR, &his_addr);
3824 	if (e != PAM_SUCCESS) {
3825 		syslog(LOG_ERR, "pam_set_item(PAM_SOCKADDR): %s",
3826 			pam_strerror(pamh, e));
3827 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
3828 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
3829 		}
3830 		pamh = NULL;
3831 		return -1;
3832 	}
3833 
3834 	e = pam_authenticate(pamh, 0);
3835 	switch (e) {
3836 	case PAM_SUCCESS:
3837 		/*
3838 		 * With PAM we support the concept of a "template"
3839 		 * user.  The user enters a login name which is
3840 		 * authenticated by PAM, usually via a remote service
3841 		 * such as RADIUS or TACACS+.  If authentication
3842 		 * succeeds, a different but related "template" name
3843 		 * is used for setting the credentials, shell, and
3844 		 * home directory.  The name the user enters need only
3845 		 * exist on the remote authentication server, but the
3846 		 * template name must be present in the local password
3847 		 * database.
3848 		 *
3849 		 * This is supported by two various mechanisms in the
3850 		 * individual modules.  However, from the application's
3851 		 * point of view, the template user is always passed
3852 		 * back as a changed value of the PAM_USER item.
3853 		 */
3854 		if ((e = pam_get_item(pamh, PAM_USER, &item)) ==
3855 		    PAM_SUCCESS) {
3856 			tmpl_user = (const char *) item;
3857 			if (pw == NULL
3858 			    || strcmp(pw->pw_name, tmpl_user) != 0) {
3859 				pw = sgetpwnam(tmpl_user);
3860 				if (ftpd_debug)
3861 					syslog(LOG_DEBUG,
3862 					    "PAM changed user from %s to %s",
3863 					    curname, pw->pw_name);
3864 				(void)strlcpy(curname, pw->pw_name,
3865 				    curname_len);
3866 			}
3867 		} else
3868 			syslog(LOG_ERR, "Couldn't get PAM_USER: %s",
3869 			    pam_strerror(pamh, e));
3870 		rval = 0;
3871 		break;
3872 
3873 	case PAM_AUTH_ERR:
3874 	case PAM_USER_UNKNOWN:
3875 	case PAM_MAXTRIES:
3876 		rval = 1;
3877 		break;
3878 
3879 	default:
3880 		syslog(LOG_ERR, "pam_authenticate: %s", pam_strerror(pamh, e));
3881 		rval = -1;
3882 		break;
3883 	}
3884 
3885 	if (rval == 0) {
3886 		e = pam_acct_mgmt(pamh, 0);
3887 		if (e != PAM_SUCCESS) {
3888 			syslog(LOG_ERR, "pam_acct_mgmt: %s",
3889 						pam_strerror(pamh, e));
3890 			rval = 1;
3891 		}
3892 	}
3893 
3894 	if (rval != 0) {
3895 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
3896 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
3897 		}
3898 		pamh = NULL;
3899 	}
3900 	return rval;
3901 }
3902 
3903 #endif /* USE_PAM */
3904