xref: /netbsd-src/libexec/ftpd/ftpd.c (revision 181254a7b1bdde6873432bffef2d2decc4b5c22f)
1 /*	$NetBSD: ftpd.c,v 1.205 2019/10/15 18:29:32 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 1997-2009 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  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994
34  *	The Regents of the University of California.  All rights reserved.
35  *
36  * Redistribution and use in source and binary forms, with or without
37  * modification, are permitted provided that the following conditions
38  * are met:
39  * 1. Redistributions of source code must retain the above copyright
40  *    notice, this list of conditions and the following disclaimer.
41  * 2. Redistributions in binary form must reproduce the above copyright
42  *    notice, this list of conditions and the following disclaimer in the
43  *    documentation and/or other materials provided with the distribution.
44  * 3. Neither the name of the University nor the names of its contributors
45  *    may be used to endorse or promote products derived from this software
46  *    without specific prior written permission.
47  *
48  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
49  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
50  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
51  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
52  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
53  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
54  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
55  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
56  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
57  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
58  * SUCH DAMAGE.
59  */
60 
61 /*
62  * Copyright (C) 1997 and 1998 WIDE Project.
63  * All rights reserved.
64  *
65  * Redistribution and use in source and binary forms, with or without
66  * modification, are permitted provided that the following conditions
67  * are met:
68  * 1. Redistributions of source code must retain the above copyright
69  *    notice, this list of conditions and the following disclaimer.
70  * 2. Redistributions in binary form must reproduce the above copyright
71  *    notice, this list of conditions and the following disclaimer in the
72  *    documentation and/or other materials provided with the distribution.
73  * 3. Neither the name of the project nor the names of its contributors
74  *    may be used to endorse or promote products derived from this software
75  *    without specific prior written permission.
76  *
77  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
78  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
79  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
80  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
81  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
82  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
83  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
84  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
85  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
86  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
87  * SUCH DAMAGE.
88  */
89 
90 #include <sys/cdefs.h>
91 #ifndef lint
92 __COPYRIGHT("@(#) Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994\
93  The Regents of the University of California.  All rights reserved.");
94 #endif /* not lint */
95 
96 #ifndef lint
97 #if 0
98 static char sccsid[] = "@(#)ftpd.c	8.5 (Berkeley) 4/28/95";
99 #else
100 __RCSID("$NetBSD: ftpd.c,v 1.205 2019/10/15 18:29:32 christos Exp $");
101 #endif
102 #endif /* not lint */
103 
104 /*
105  * FTP server.
106  */
107 #include <sys/param.h>
108 #include <sys/stat.h>
109 #include <sys/ioctl.h>
110 #include <sys/socket.h>
111 #include <sys/wait.h>
112 #include <sys/mman.h>
113 #include <sys/resource.h>
114 
115 #include <netinet/in.h>
116 #include <netinet/in_systm.h>
117 #include <netinet/ip.h>
118 
119 #define	FTP_NAMES
120 #include <arpa/ftp.h>
121 #include <arpa/inet.h>
122 #include <arpa/telnet.h>
123 
124 #include <ctype.h>
125 #include <dirent.h>
126 #include <err.h>
127 #include <errno.h>
128 #include <fcntl.h>
129 #include <fnmatch.h>
130 #include <glob.h>
131 #include <grp.h>
132 #include <limits.h>
133 #include <netdb.h>
134 #include <pwd.h>
135 #include <poll.h>
136 #include <signal.h>
137 #include <stdarg.h>
138 #include <stdio.h>
139 #include <stdlib.h>
140 #include <string.h>
141 #include <syslog.h>
142 #include <time.h>
143 #include <tzfile.h>
144 #include <unistd.h>
145 #include <util.h>
146 #ifdef SUPPORT_UTMP
147 #include <utmp.h>
148 #endif
149 #ifdef SUPPORT_UTMPX
150 #include <utmpx.h>
151 #endif
152 #ifdef SKEY
153 #include <skey.h>
154 #endif
155 #ifdef KERBEROS5
156 #include <com_err.h>
157 #include <krb5/krb5.h>
158 #endif
159 
160 #ifdef	LOGIN_CAP
161 #include <login_cap.h>
162 #endif
163 
164 #ifdef USE_PAM
165 #include <security/pam_appl.h>
166 #endif
167 
168 #include "pfilter.h"
169 
170 #define	GLOBAL
171 #include "extern.h"
172 #include "pathnames.h"
173 #include "version.h"
174 
175 static sig_atomic_t	transflag;
176 static sig_atomic_t	urgflag;
177 
178 int	data;
179 int	Dflag;
180 int	fflag;
181 int	sflag;
182 int	stru;			/* avoid C keyword */
183 int	mode;
184 int	dataport;		/* use specific data port */
185 int	dopidfile;		/* maintain pid file */
186 int	doutmp;			/* update utmp file */
187 int	dowtmp;			/* update wtmp file */
188 int	doxferlog;		/* syslog/write wu-ftpd style xferlog entries */
189 int	xferlogfd;		/* fd to write wu-ftpd xferlog entries to */
190 int	getnameopts;		/* flags for use with getname() */
191 int	dropprivs;		/* if privileges should or have been dropped */
192 int	mapped;			/* IPv4 connection on AF_INET6 socket */
193 off_t	file_size;
194 off_t	byte_count;
195 static char ttyline[20];
196 
197 #ifdef USE_PAM
198 static int	auth_pam(void);
199 pam_handle_t	*pamh = NULL;
200 #endif
201 
202 #ifdef SUPPORT_UTMP
203 static struct utmp utmp;	/* for utmp */
204 #endif
205 #ifdef SUPPORT_UTMPX
206 static struct utmpx utmpx;	/* for utmpx */
207 #endif
208 
209 static const char *anondir = NULL;
210 static const char *confdir = _DEFAULT_CONFDIR;
211 
212 static char	*curname;		/* current USER name */
213 static size_t	curname_len;		/* length of curname (include NUL) */
214 
215 #if defined(KERBEROS) || defined(KERBEROS5)
216 int	has_ccache = 0;
217 int	notickets = 1;
218 char	*krbtkfile_env = NULL;
219 char	*tty = ttyline;
220 int	login_krb5_forwardable_tgt = 0;
221 #endif
222 
223 int epsvall = 0;
224 
225 /*
226  * Timeout intervals for retrying connections
227  * to hosts that don't accept PORT cmds.  This
228  * is a kludge, but given the problems with TCP...
229  */
230 #define	SWAITMAX	90	/* wait at most 90 seconds */
231 #define	SWAITINT	5	/* interval between retries */
232 
233 int	swaitmax = SWAITMAX;
234 int	swaitint = SWAITINT;
235 
236 enum send_status {
237 	SS_SUCCESS,
238 	SS_ABORTED,			/* transfer aborted */
239 	SS_NO_TRANSFER,			/* no transfer made yet */
240 	SS_FILE_ERROR,			/* file read error */
241 	SS_DATA_ERROR			/* data send error */
242 };
243 
244 static int	 bind_pasv_addr(void);
245 static int	 checkuser(const char *, const char *, int, int, char **);
246 static int	 checkaccess(const char *);
247 static int	 checkpassword(const struct passwd *, const char *);
248 static void	 do_pass(int, int, const char *);
249 static void	 end_login(void);
250 static FILE	*getdatasock(const char *);
251 static char	*gunique(const char *);
252 static void	 login_utmp(const char *, const char *, const char *,
253 		     struct sockinet *);
254 static void	 logremotehost(struct sockinet *);
255 __dead static void	 lostconn(int);
256 __dead static void	 toolong(int);
257 __dead static void	 sigquit(int);
258 static void	 sigurg(int);
259 static int	 handleoobcmd(void);
260 static int	 receive_data(FILE *, FILE *);
261 static int	 send_data(FILE *, FILE *, const struct stat *, int);
262 static struct passwd *sgetpwnam(const char *);
263 static int	 write_data(int, char *, size_t, off_t *, struct timeval *,
264 		     int);
265 static enum send_status
266 		 send_data_with_read(int, int, const struct stat *, int);
267 static enum send_status
268 		 send_data_with_mmap(int, int, const struct stat *, int);
269 static void	 logrusage(const struct rusage *, const struct rusage *);
270 static void	 logout_utmp(void);
271 
272 int	main(int, char *[]);
273 
274 #if defined(KERBEROS)
275 int	klogin(struct passwd *, char *, char *, char *);
276 void	kdestroy(void);
277 #endif
278 #if defined(KERBEROS5)
279 int	k5login(struct passwd *, char *, char *, char *);
280 void	k5destroy(void);
281 #endif
282 
283 int
284 main(int argc, char *argv[])
285 {
286 	int		ch, on = 1, tos, keepalive;
287 	socklen_t	addrlen;
288 #ifdef KERBEROS5
289 	krb5_error_code	kerror;
290 #endif
291 	char		*p;
292 	const char	*xferlogname = NULL;
293 	long		l;
294 	struct sigaction sa;
295 	sa_family_t	af = AF_UNSPEC;
296 
297 	connections = 1;
298 	ftpd_debug = 0;
299 	logging = 0;
300 	pdata = -1;
301 	Dflag = 0;
302 	fflag = 0;
303 	sflag = 0;
304 	dataport = 0;
305 	dopidfile = 1;		/* default: DO use a pid file to count users */
306 	doutmp = 0;		/* default: Do NOT log to utmp */
307 	dowtmp = 1;		/* default: DO log to wtmp */
308 	doxferlog = 0;		/* default: Do NOT syslog xferlog */
309 	xferlogfd = -1;		/* default: Do NOT write xferlog file */
310 	getnameopts = 0;	/* default: xlate addrs to name */
311 	dropprivs = 0;
312 	mapped = 0;
313 	usedefault = 1;
314 	emailaddr = NULL;
315 	hostname[0] = '\0';
316 	homedir[0] = '\0';
317 	gidcount = 0;
318 	is_oob = 0;
319 	version = FTPD_VERSION;
320 
321 	/*
322 	 * LOG_NDELAY sets up the logging connection immediately,
323 	 * necessary for anonymous ftp's that chroot and can't do it later.
324 	 */
325 	openlog("ftpd", LOG_PID | LOG_NDELAY, LOG_FTP);
326 
327 	while ((ch = getopt(argc, argv,
328 	    "46a:c:C:Dde:fh:HlL:nP:qQrst:T:uUvV:wWX")) != -1) {
329 		switch (ch) {
330 		case '4':
331 			af = AF_INET;
332 			break;
333 
334 		case '6':
335 			af = AF_INET6;
336 			break;
337 
338 		case 'a':
339 			anondir = optarg;
340 			break;
341 
342 		case 'c':
343 			confdir = optarg;
344 			break;
345 
346 		case 'C':
347 			if ((p = strchr(optarg, '@')) != NULL) {
348 				*p++ = '\0';
349 				strlcpy(remotehost, p, MAXHOSTNAMELEN + 1);
350 				if (inet_pton(AF_INET, p,
351 				    &his_addr.su_addr) == 1) {
352 					his_addr.su_family = AF_INET;
353 					his_addr.su_len =
354 					    sizeof(his_addr.si_su.su_sin);
355 #ifdef INET6
356 				} else if (inet_pton(AF_INET6, p,
357 				    &his_addr.su_6addr) == 1) {
358 					his_addr.su_family = AF_INET6;
359 					his_addr.su_len =
360 					    sizeof(his_addr.si_su.su_sin6);
361 #endif
362 				} else
363 					his_addr.su_family = AF_UNSPEC;
364 			}
365 			pw = sgetpwnam(optarg);
366 			exit(checkaccess(optarg) ? 0 : 1);
367 			/* NOTREACHED */
368 
369 		case 'D':
370 			Dflag = 1;
371 			break;
372 
373 		case 'd':
374 		case 'v':		/* deprecated */
375 			ftpd_debug = 1;
376 			break;
377 
378 		case 'e':
379 			emailaddr = optarg;
380 			break;
381 
382 		case 'f':
383 			fflag = 1;
384 			break;
385 
386 		case 'h':
387 			strlcpy(hostname, optarg, sizeof(hostname));
388 			break;
389 
390 		case 'H':
391 			if (gethostname(hostname, sizeof(hostname)) == -1)
392 				hostname[0] = '\0';
393 			hostname[sizeof(hostname) - 1] = '\0';
394 			break;
395 
396 		case 'l':
397 			logging++;	/* > 1 == extra logging */
398 			break;
399 
400 		case 'L':
401 			xferlogname = optarg;
402 			break;
403 
404 		case 'n':
405 			getnameopts = NI_NUMERICHOST;
406 			break;
407 
408 		case 'P':
409 			errno = 0;
410 			p = NULL;
411 			l = strtol(optarg, &p, 10);
412 			if (errno || *optarg == '\0' || *p != '\0' ||
413 			    l < IPPORT_RESERVED ||
414 			    l > IPPORT_ANONMAX) {
415 				syslog(LOG_WARNING, "Invalid dataport %s",
416 				    optarg);
417 				dataport = 0;
418 			}
419 			dataport = (int)l;
420 			break;
421 
422 		case 'q':
423 			dopidfile = 1;
424 			break;
425 
426 		case 'Q':
427 			dopidfile = 0;
428 			break;
429 
430 		case 'r':
431 			dropprivs = 1;
432 			break;
433 
434 		case 's':
435 			sflag = 1;
436 			break;
437 
438 		case 't':
439 		case 'T':
440 			syslog(LOG_WARNING,
441 			    "-%c has been deprecated in favour of ftpd.conf",
442 			    ch);
443 			break;
444 
445 		case 'u':
446 			doutmp = 1;
447 			break;
448 
449 		case 'U':
450 			doutmp = 0;
451 			break;
452 
453 		case 'V':
454 			if (EMPTYSTR(optarg) || strcmp(optarg, "-") == 0)
455 				version = NULL;
456 			else
457 				version = ftpd_strdup(optarg);
458 			break;
459 
460 		case 'w':
461 			dowtmp = 1;
462 			break;
463 
464 		case 'W':
465 			dowtmp = 0;
466 			break;
467 
468 		case 'X':
469 			doxferlog |= 1;
470 			break;
471 
472 		default:
473 			if (optopt == 'a' || optopt == 'C')
474 				exit(1);
475 			syslog(LOG_WARNING, "unknown flag -%c ignored", optopt);
476 			break;
477 		}
478 	}
479 	if (EMPTYSTR(confdir))
480 		confdir = _DEFAULT_CONFDIR;
481 
482 	pfilter_open();
483 
484 	if (dowtmp) {
485 #ifdef SUPPORT_UTMPX
486 		ftpd_initwtmpx();
487 #endif
488 #ifdef SUPPORT_UTMP
489 		ftpd_initwtmp();
490 #endif
491 	}
492 	errno = 0;
493 	l = sysconf(_SC_LOGIN_NAME_MAX);
494 	if (l == -1 && errno != 0) {
495 		syslog(LOG_ERR, "sysconf _SC_LOGIN_NAME_MAX: %m");
496 		exit(1);
497 	} else if (l <= 0) {
498 		syslog(LOG_WARNING, "using conservative LOGIN_NAME_MAX value");
499 		curname_len = _POSIX_LOGIN_NAME_MAX;
500 	} else
501 		curname_len = (size_t)l;
502 	curname = malloc(curname_len);
503 	if (curname == NULL) {
504 		syslog(LOG_ERR, "malloc: %m");
505 		exit(1);
506 	}
507 	curname[0] = '\0';
508 
509 	if (Dflag) {
510 		int error, fd, i, n, *socks;
511 		struct pollfd *fds;
512 		struct addrinfo hints, *res, *res0;
513 
514 		if (!fflag && daemon(1, 0) == -1) {
515 			syslog(LOG_ERR, "failed to daemonize: %m");
516 			exit(1);
517 		}
518 		(void)memset(&sa, 0, sizeof(sa));
519 		sa.sa_handler = SIG_IGN;
520 		sa.sa_flags = SA_NOCLDWAIT;
521 		sigemptyset(&sa.sa_mask);
522 		(void)sigaction(SIGCHLD, &sa, NULL);
523 
524 		(void)memset(&hints, 0, sizeof(hints));
525 		hints.ai_flags = AI_PASSIVE;
526 		hints.ai_family = af;
527 		hints.ai_socktype = SOCK_STREAM;
528 		error = getaddrinfo(NULL, "ftp", &hints, &res0);
529 		if (error) {
530 			syslog(LOG_ERR, "getaddrinfo: %s", gai_strerror(error));
531 			exit(1);
532 		}
533 
534 		for (n = 0, res = res0; res != NULL; res = res->ai_next)
535 			n++;
536 		if (n == 0) {
537 			syslog(LOG_ERR, "no addresses available");
538 			exit(1);
539 		}
540 		socks = malloc(n * sizeof(int));
541 		fds = malloc(n * sizeof(struct pollfd));
542 		if (socks == NULL || fds == NULL) {
543 			syslog(LOG_ERR, "malloc: %m");
544 			exit(1);
545 		}
546 
547 		for (n = 0, res = res0; res != NULL; res = res->ai_next) {
548 			socks[n] = socket(res->ai_family, res->ai_socktype,
549 			    res->ai_protocol);
550 			if (socks[n] == -1)
551 				continue;
552 			(void)setsockopt(socks[n], SOL_SOCKET, SO_REUSEADDR,
553 			    &on, sizeof(on));
554 			if (bind(socks[n], res->ai_addr, res->ai_addrlen)
555 			    == -1) {
556 				(void)close(socks[n]);
557 				continue;
558 			}
559 			if (listen(socks[n], 12) == -1) {
560 				(void)close(socks[n]);
561 				continue;
562 			}
563 
564 			fds[n].fd = socks[n];
565 			fds[n].events = POLLIN;
566 			n++;
567 		}
568 		if (n == 0) {
569 			syslog(LOG_ERR, "%m");
570 			exit(1);
571 		}
572 		freeaddrinfo(res0);
573 
574 		if (pidfile(NULL) == -1)
575 			syslog(LOG_ERR, "failed to write a pid file: %m");
576 
577 		for (;;) {
578 			if (poll(fds, n, INFTIM) == -1) {
579 				if (errno == EINTR)
580 					continue;
581 				syslog(LOG_ERR, "poll: %m");
582 				exit(1);
583 			}
584 			for (i = 0; i < n; i++) {
585 				if (fds[i].revents & POLLIN) {
586 					fd = accept(fds[i].fd, NULL, NULL);
587 					if (fd == -1) {
588 						syslog(LOG_ERR, "accept: %m");
589 						continue;
590 					}
591 					switch (fork()) {
592 					case -1:
593 						syslog(LOG_ERR, "fork: %m");
594 						break;
595 					case 0:
596 						goto child;
597 						/* NOTREACHED */
598 					}
599 					(void)close(fd);
600 				}
601 			}
602 		}
603  child:
604 		(void)dup2(fd, STDIN_FILENO);
605 		(void)dup2(fd, STDOUT_FILENO);
606 		(void)dup2(fd, STDERR_FILENO);
607 		for (i = 0; i < n; i++)
608 			(void)close(socks[i]);
609 	}
610 
611 	memset((char *)&his_addr, 0, sizeof(his_addr));
612 	addrlen = sizeof(his_addr.si_su);
613 	if (getpeername(0, (struct sockaddr *)&his_addr.si_su, &addrlen) < 0) {
614 		syslog((errno == ENOTCONN) ? LOG_NOTICE : LOG_ERR,
615 		    "getpeername (%s): %m",argv[0]);
616 		exit(1);
617 	}
618 	his_addr.su_len = addrlen;
619 	memset((char *)&ctrl_addr, 0, sizeof(ctrl_addr));
620 	addrlen = sizeof(ctrl_addr.si_su);
621 	if (getsockname(0, (struct sockaddr *)&ctrl_addr, &addrlen) < 0) {
622 		syslog(LOG_ERR, "getsockname (%s): %m",argv[0]);
623 		exit(1);
624 	}
625 	ctrl_addr.su_len = addrlen;
626 #ifdef INET6
627 	if (his_addr.su_family == AF_INET6
628 	 && IN6_IS_ADDR_V4MAPPED(&his_addr.su_6addr)) {
629 #if 1
630 		/*
631 		 * IPv4 control connection arrived to AF_INET6 socket.
632 		 * I hate to do this, but this is the easiest solution.
633 		 *
634 		 * The assumption is untrue on SIIT environment.
635 		 */
636 		struct sockinet tmp_addr;
637 		const int off = sizeof(struct in6_addr) - sizeof(struct in_addr);
638 
639 		tmp_addr = his_addr;
640 		memset(&his_addr, 0, sizeof(his_addr));
641 		his_addr.su_family = AF_INET;
642 		his_addr.su_len = sizeof(his_addr.si_su.su_sin);
643 		memcpy(&his_addr.su_addr, &tmp_addr.su_6addr.s6_addr[off],
644 		    sizeof(his_addr.su_addr));
645 		his_addr.su_port = tmp_addr.su_port;
646 
647 		tmp_addr = ctrl_addr;
648 		memset(&ctrl_addr, 0, sizeof(ctrl_addr));
649 		ctrl_addr.su_family = AF_INET;
650 		ctrl_addr.su_len = sizeof(ctrl_addr.si_su.su_sin);
651 		memcpy(&ctrl_addr.su_addr, &tmp_addr.su_6addr.s6_addr[off],
652 		    sizeof(ctrl_addr.su_addr));
653 		ctrl_addr.su_port = tmp_addr.su_port;
654 #else
655 		while (fgets(line, sizeof(line), fd) != NULL) {
656 			if ((cp = strchr(line, '\n')) != NULL)
657 				*cp = '\0';
658 			reply(-530, "%s", line);
659 		}
660 		(void) fflush(stdout);
661 		(void) fclose(fd);
662 		reply(530,
663 		    "Connection from IPv4 mapped address is not supported.");
664 		exit(0);
665 #endif
666 
667 		mapped = 1;
668 	} else
669 #endif /* INET6 */
670 		mapped = 0;
671 #ifdef IP_TOS
672 	if (!mapped && his_addr.su_family == AF_INET) {
673 		tos = IPTOS_LOWDELAY;
674 		if (setsockopt(0, IPPROTO_IP, IP_TOS, (char *)&tos,
675 			       sizeof(int)) < 0)
676 			syslog(LOG_WARNING, "setsockopt (IP_TOS): %m");
677 	}
678 #endif
679 	/* if the hostname hasn't been given, attempt to determine it */
680 	if (hostname[0] == '\0') {
681 		if (getnameinfo((struct sockaddr *)&ctrl_addr.si_su,
682 		    ctrl_addr.su_len, hostname, sizeof(hostname), NULL, 0,
683 			getnameopts) != 0)
684 			(void)gethostname(hostname, sizeof(hostname));
685 		hostname[sizeof(hostname) - 1] = '\0';
686 	}
687 
688 	/* set this here so klogin can use it... */
689 	(void)snprintf(ttyline, sizeof(ttyline), "ftp%d", getpid());
690 
691 	(void) freopen(_PATH_DEVNULL, "w", stderr);
692 
693 	memset(&sa, 0, sizeof(sa));
694 	sa.sa_handler = SIG_DFL;
695 	sa.sa_flags = SA_RESTART;
696 	sigemptyset(&sa.sa_mask);
697 	(void) sigaction(SIGCHLD, &sa, NULL);
698 
699 	sa.sa_handler = sigquit;
700 	sa.sa_flags = SA_RESTART;
701 	sigfillset(&sa.sa_mask);	/* block all sigs in these handlers */
702 	(void) sigaction(SIGHUP, &sa, NULL);
703 	(void) sigaction(SIGINT, &sa, NULL);
704 	(void) sigaction(SIGQUIT, &sa, NULL);
705 	(void) sigaction(SIGTERM, &sa, NULL);
706 	sa.sa_handler = lostconn;
707 	(void) sigaction(SIGPIPE, &sa, NULL);
708 	sa.sa_handler = toolong;
709 	(void) sigaction(SIGALRM, &sa, NULL);
710 	sa.sa_handler = sigurg;
711 	(void) sigaction(SIGURG, &sa, NULL);
712 
713 	/* Try to handle urgent data inline */
714 #ifdef SO_OOBINLINE
715 	if (setsockopt(0, SOL_SOCKET, SO_OOBINLINE, (char *)&on, sizeof(on)) < 0)
716 		syslog(LOG_WARNING, "setsockopt: %m");
717 #endif
718 	/* Set keepalives on the socket to detect dropped connections.  */
719 #ifdef SO_KEEPALIVE
720 	keepalive = 1;
721 	if (setsockopt(0, SOL_SOCKET, SO_KEEPALIVE, (char *)&keepalive,
722 	    sizeof(int)) < 0)
723 		syslog(LOG_WARNING, "setsockopt (SO_KEEPALIVE): %m");
724 #endif
725 
726 #ifdef	F_SETOWN
727 	if (fcntl(fileno(stdin), F_SETOWN, getpid()) == -1)
728 		syslog(LOG_WARNING, "fcntl F_SETOWN: %m");
729 #endif
730 	logremotehost(&his_addr);
731 	/*
732 	 * Set up default state
733 	 */
734 	data = -1;
735 	type = TYPE_A;
736 	form = FORM_N;
737 	stru = STRU_F;
738 	mode = MODE_S;
739 	tmpline[0] = '\0';
740 	hasyyerrored = 0;
741 
742 #ifdef KERBEROS5
743 	kerror = krb5_init_context(&kcontext);
744 	if (kerror) {
745 		syslog(LOG_ERR, "%s when initializing Kerberos context",
746 		    error_message(kerror));
747 		exit(0);
748 	}
749 #endif /* KERBEROS5 */
750 
751 	init_curclass();
752 	curclass.timeout = 300;		/* 5 minutes, as per login(1) */
753 	curclass.type = CLASS_REAL;
754 
755 	/* If logins are disabled, print out the message. */
756 	if (display_file(_PATH_NOLOGIN, 530)) {
757 		reply(530, "System not available.");
758 		exit(0);
759 	}
760 	(void)display_file(conffilename(_NAME_FTPWELCOME), 220);
761 		/* reply(220,) must follow */
762 	if (EMPTYSTR(version))
763 		reply(220, "%s FTP server ready.", hostname);
764 	else
765 		reply(220, "%s FTP server (%s) ready.", hostname, version);
766 
767 	if (xferlogname != NULL) {
768 		xferlogfd = open(xferlogname, O_WRONLY | O_APPEND | O_CREAT,
769 		    0660);
770 		if (xferlogfd == -1)
771 			syslog(LOG_WARNING, "open xferlog `%s': %m",
772 			    xferlogname);
773 		else
774 			doxferlog |= 2;
775 	}
776 
777 	ftp_loop();
778 	/* NOTREACHED */
779 }
780 
781 static void
782 lostconn(int signo __unused)
783 {
784 
785 	if (ftpd_debug)
786 		syslog(LOG_DEBUG, "lost connection");
787 	dologout(1);
788 }
789 
790 static void
791 toolong(int signo __unused)
792 {
793 
794 		/* XXXSIGRACE */
795 	reply(421,
796 	    "Timeout (" LLF " seconds): closing control connection.",
797 	    (LLT)curclass.timeout);
798 	if (logging)
799 		syslog(LOG_INFO, "User %s timed out after " LLF " seconds",
800 		    (pw ? pw->pw_name : "unknown"), (LLT)curclass.timeout);
801 	dologout(1);
802 }
803 
804 static void
805 sigquit(int signo)
806 {
807 
808 	if (ftpd_debug)
809 		syslog(LOG_DEBUG, "got signal %d", signo);
810 	dologout(1);
811 }
812 
813 static void
814 sigurg(int signo __unused)
815 {
816 
817 	urgflag = 1;
818 }
819 
820 
821 /*
822  * Save the result of a getpwnam.  Used for USER command, since
823  * the data returned must not be clobbered by any other command
824  * (e.g., globbing).
825  */
826 static struct passwd *
827 sgetpwnam(const char *name)
828 {
829 	static struct passwd save;
830 	struct passwd *p;
831 
832 	if ((p = getpwnam(name)) == NULL)
833 		return (p);
834 	if (save.pw_name) {
835 		free((char *)save.pw_name);
836 		memset(save.pw_passwd, 0, strlen(save.pw_passwd));
837 		free((char *)save.pw_passwd);
838 		free((char *)save.pw_gecos);
839 		free((char *)save.pw_dir);
840 		free((char *)save.pw_shell);
841 	}
842 	save = *p;
843 	save.pw_name = ftpd_strdup(p->pw_name);
844 	save.pw_passwd = ftpd_strdup(p->pw_passwd);
845 	save.pw_gecos = ftpd_strdup(p->pw_gecos);
846 	save.pw_dir = ftpd_strdup(p->pw_dir);
847 	save.pw_shell = ftpd_strdup(p->pw_shell);
848 	return (&save);
849 }
850 
851 static int	login_attempts;	/* number of failed login attempts */
852 static int	askpasswd;	/* had USER command, ask for PASSwd */
853 static int	permitted;	/* USER permitted */
854 
855 /*
856  * USER command.
857  * Sets global passwd pointer pw if named account exists and is acceptable;
858  * sets askpasswd if a PASS command is expected.  If logged in previously,
859  * need to reset state.  If name is "ftp" or "anonymous", the name is not in
860  * _NAME_FTPUSERS, and ftp account exists, set guest and pw, then just return.
861  * If account doesn't exist, ask for passwd anyway.  Otherwise, check user
862  * requesting login privileges.  Disallow anyone who does not have a standard
863  * shell as returned by getusershell().  Disallow anyone mentioned in the file
864  * _NAME_FTPUSERS to allow people such as root and uucp to be avoided.
865  */
866 void
867 user(const char *name)
868 {
869 	char	*class;
870 #ifdef	LOGIN_CAP
871 	login_cap_t *lc = NULL;
872 #endif
873 #ifdef USE_PAM
874 	int e;
875 #endif
876 
877 	class = NULL;
878 	if (logged_in) {
879 		switch (curclass.type) {
880 		case CLASS_GUEST:
881 			reply(530, "Can't change user from guest login.");
882 			return;
883 		case CLASS_CHROOT:
884 			reply(530, "Can't change user from chroot user.");
885 			return;
886 		case CLASS_REAL:
887 			if (dropprivs) {
888 				reply(530, "Can't change user.");
889 				return;
890 			}
891 			end_login();
892 			break;
893 		default:
894 			abort();
895 		}
896 	}
897 
898 #if defined(KERBEROS)
899 	kdestroy();
900 #endif
901 #if defined(KERBEROS5)
902 	k5destroy();
903 #endif
904 
905 	curclass.type = CLASS_REAL;
906 	askpasswd = 0;
907 	permitted = 0;
908 
909 	if (strcmp(name, "ftp") == 0 || strcmp(name, "anonymous") == 0) {
910 			/* need `pw' setup for checkaccess() and checkuser () */
911 		if ((pw = sgetpwnam("ftp")) == NULL)
912 			reply(530, "User %s unknown.", name);
913 		else if (! checkaccess("ftp") || ! checkaccess("anonymous"))
914 			reply(530, "User %s access denied.", name);
915 		else {
916 			curclass.type = CLASS_GUEST;
917 			askpasswd = 1;
918 			reply(331,
919 			    "Guest login ok, type your name as password.");
920 		}
921 		if (!askpasswd) {
922 			if (logging)
923 				syslog(LOG_NOTICE,
924 				    "ANONYMOUS FTP LOGIN REFUSED FROM %s",
925 				    remoteloghost);
926 			end_login();
927 			goto cleanup_user;
928 		}
929 		name = "ftp";
930 	} else
931 		pw = sgetpwnam(name);
932 
933 	strlcpy(curname, name, curname_len);
934 
935 			/* check user in /etc/ftpusers, and setup class */
936 	permitted = checkuser(_NAME_FTPUSERS, curname, 1, 0, &class);
937 
938 			/* check user in /etc/ftpchroot */
939 #ifdef	LOGIN_CAP
940 	lc = login_getpwclass(pw);
941 #endif
942 	if (checkuser(_NAME_FTPCHROOT, curname, 0, 0, NULL)
943 #ifdef	LOGIN_CAP	/* Allow login.conf configuration as well */
944 	    || login_getcapbool(lc, "ftp-chroot", 0)
945 #endif
946 	) {
947 		if (curclass.type == CLASS_GUEST) {
948 			syslog(LOG_NOTICE,
949 	    "Can't change guest user to chroot class; remove entry in %s",
950 			    _NAME_FTPCHROOT);
951 			exit(1);
952 		}
953 		curclass.type = CLASS_CHROOT;
954 	}
955 
956 			/* determine default class */
957 	if (class == NULL) {
958 		switch (curclass.type) {
959 		case CLASS_GUEST:
960 			class = ftpd_strdup("guest");
961 			break;
962 		case CLASS_CHROOT:
963 			class = ftpd_strdup("chroot");
964 			break;
965 		case CLASS_REAL:
966 			class = ftpd_strdup("real");
967 			break;
968 		default:
969 			syslog(LOG_ERR, "unknown curclass.type %d; aborting",
970 			    curclass.type);
971 			abort();
972 		}
973 	}
974 			/* parse ftpd.conf, setting up various parameters */
975 	parse_conf(class);
976 			/* if not guest user, check for valid shell */
977 	if (pw == NULL)
978 		permitted = 0;
979 	else {
980 		const char	*cp, *shell;
981 
982 		if ((shell = pw->pw_shell) == NULL || *shell == 0)
983 			shell = _PATH_BSHELL;
984 		while ((cp = getusershell()) != NULL)
985 			if (strcmp(cp, shell) == 0)
986 				break;
987 		endusershell();
988 		if (cp == NULL && curclass.type != CLASS_GUEST)
989 			permitted = 0;
990 	}
991 
992 			/* deny quickly (after USER not PASS) if requested */
993 	if (CURCLASS_FLAGS_ISSET(denyquick) && !permitted) {
994 		reply(530, "User %s may not use FTP.", curname);
995 		if (logging)
996 			syslog(LOG_NOTICE, "FTP LOGIN REFUSED FROM %s, %s",
997 			    remoteloghost, curname);
998 		end_login();
999 		goto cleanup_user;
1000 	}
1001 
1002 			/* if haven't asked yet (i.e, not anon), ask now */
1003 	if (!askpasswd) {
1004 		askpasswd = 1;
1005 #ifdef USE_PAM
1006 		e = auth_pam();		/* this does reply(331, ...) */
1007 		do_pass(1, e, "");
1008 		goto cleanup_user;
1009 #else /* !USE_PAM */
1010 #ifdef SKEY
1011 		if (skey_haskey(curname) == 0) {
1012 			const char *myskey;
1013 
1014 			myskey = skey_keyinfo(curname);
1015 			reply(331, "Password [ %s ] required for %s.",
1016 			    myskey ? myskey : "error getting challenge",
1017 			    curname);
1018 		} else
1019 #endif
1020 			reply(331, "Password required for %s.", curname);
1021 #endif /* !USE_PAM */
1022 	}
1023 
1024  cleanup_user:
1025 #ifdef LOGIN_CAP
1026 	login_close(lc);
1027 #endif
1028 	/*
1029 	 * Delay before reading passwd after first failed
1030 	 * attempt to slow down passwd-guessing programs.
1031 	 */
1032 	if (login_attempts)
1033 		sleep((unsigned) login_attempts);
1034 
1035 	if (class)
1036 		free(class);
1037 }
1038 
1039 /*
1040  * Determine whether something is to happen (allow access, chroot)
1041  * for a user. Each line is a shell-style glob followed by
1042  * `yes' or `no'.
1043  *
1044  * For backward compatibility, `allow' and `deny' are synonymns
1045  * for `yes' and `no', respectively.
1046  *
1047  * Each glob is matched against the username in turn, and the first
1048  * match found is used. If no match is found, the result is the
1049  * argument `def'. If a match is found but without and explicit
1050  * `yes'/`no', the result is the opposite of def.
1051  *
1052  * If the file doesn't exist at all, the result is the argument
1053  * `nofile'
1054  *
1055  * Any line starting with `#' is considered a comment and ignored.
1056  *
1057  * Returns 0 if the user is denied, or 1 if they are allowed.
1058  *
1059  * NOTE: needs struct passwd *pw setup before use.
1060  */
1061 static int
1062 checkuser(const char *fname, const char *name, int def, int nofile,
1063 	    char **retclass)
1064 {
1065 	FILE	*fd;
1066 	int	 retval;
1067 	char	*word, *perm, *class, *buf, *p;
1068 	size_t	 len, line;
1069 
1070 	retval = def;
1071 	if (retclass != NULL)
1072 		*retclass = NULL;
1073 	if ((fd = fopen(conffilename(fname), "r")) == NULL)
1074 		return nofile;
1075 
1076 	line = 0;
1077 	for (;
1078 	    (buf = fparseln(fd, &len, &line, NULL, FPARSELN_UNESCCOMM |
1079 			    FPARSELN_UNESCCONT | FPARSELN_UNESCESC)) != NULL;
1080 	    free(buf), buf = NULL) {
1081 		word = perm = class = NULL;
1082 		p = buf;
1083 		if (len < 1)
1084 			continue;
1085 		if (p[len - 1] == '\n')
1086 			p[--len] = '\0';
1087 		if (EMPTYSTR(p))
1088 			continue;
1089 
1090 		NEXTWORD(p, word);
1091 		NEXTWORD(p, perm);
1092 		NEXTWORD(p, class);
1093 		if (EMPTYSTR(word))
1094 			continue;
1095 		if (!EMPTYSTR(class)) {
1096 			if (strcasecmp(class, "all") == 0 ||
1097 			    strcasecmp(class, "none") == 0) {
1098 				syslog(LOG_WARNING,
1099 		"%s line %d: illegal user-defined class `%s' - skipping entry",
1100 					    fname, (int)line, class);
1101 				continue;
1102 			}
1103 		}
1104 
1105 					/* have a host specifier */
1106 		if ((p = strchr(word, '@')) != NULL) {
1107 			unsigned char	net[16], mask[16], *addr;
1108 			int		addrlen, bits, bytes, a;
1109 
1110 			*p++ = '\0';
1111 					/* check against network or CIDR */
1112 			memset(net, 0x00, sizeof(net));
1113 			if ((bits = inet_net_pton(his_addr.su_family, p, net,
1114 			    sizeof(net))) != -1) {
1115 #ifdef INET6
1116 				if (his_addr.su_family == AF_INET) {
1117 #endif
1118 					addrlen = 4;
1119 					addr = (unsigned char *)&his_addr.su_addr;
1120 #ifdef INET6
1121 				} else {
1122 					addrlen = 16;
1123 					addr = (unsigned char *)&his_addr.su_6addr;
1124 				}
1125 #endif
1126 				bytes = bits / 8;
1127 				bits = bits % 8;
1128 				if (bytes > 0)
1129 					memset(mask, 0xFF, bytes);
1130 				if (bytes < addrlen)
1131 					mask[bytes] = 0xFF << (8 - bits);
1132 				if (bytes + 1 < addrlen)
1133 					memset(mask + bytes + 1, 0x00,
1134 					    addrlen - bytes - 1);
1135 				for (a = 0; a < addrlen; a++)
1136 					if ((addr[a] & mask[a]) != net[a])
1137 						break;
1138 				if (a < addrlen)
1139 					continue;
1140 
1141 					/* check against hostname glob */
1142 			} else if (fnmatch(p, remotehost, FNM_CASEFOLD) != 0)
1143 				continue;
1144 		}
1145 
1146 					/* have a group specifier */
1147 		if ((p = strchr(word, ':')) != NULL) {
1148 			gid_t	*groups, *ng;
1149 			int	 gsize, i, found;
1150 
1151 			if (pw == NULL)
1152 				continue;	/* no match for unknown user */
1153 			*p++ = '\0';
1154 			groups = NULL;
1155 			gsize = 16;
1156 			do {
1157 				ng = realloc(groups, gsize * sizeof(gid_t));
1158 				if (ng == NULL)
1159 					fatal(
1160 					    "Local resource failure: realloc");
1161 				groups = ng;
1162 			} while (getgrouplist(pw->pw_name, pw->pw_gid,
1163 						groups, &gsize) == -1);
1164 			found = 0;
1165 			for (i = 0; i < gsize; i++) {
1166 				struct group *g;
1167 
1168 				if ((g = getgrgid(groups[i])) == NULL)
1169 					continue;
1170 				if (fnmatch(p, g->gr_name, 0) == 0) {
1171 					found = 1;
1172 					break;
1173 				}
1174 			}
1175 			free(groups);
1176 			if (!found)
1177 				continue;
1178 		}
1179 
1180 					/* check against username glob */
1181 		if (fnmatch(word, name, 0) != 0)
1182 			continue;
1183 
1184 		if (perm != NULL &&
1185 		    ((strcasecmp(perm, "allow") == 0) ||
1186 		     (strcasecmp(perm, "yes") == 0)))
1187 			retval = 1;
1188 		else if (perm != NULL &&
1189 		    ((strcasecmp(perm, "deny") == 0) ||
1190 		     (strcasecmp(perm, "no") == 0)))
1191 			retval = 0;
1192 		else
1193 			retval = !def;
1194 		if (!EMPTYSTR(class) && retclass != NULL)
1195 			*retclass = ftpd_strdup(class);
1196 		free(buf);
1197 		break;
1198 	}
1199 	(void) fclose(fd);
1200 	return (retval);
1201 }
1202 
1203 /*
1204  * Check if user is allowed by /etc/ftpusers
1205  * returns 1 for yes, 0 for no
1206  *
1207  * NOTE: needs struct passwd *pw setup (for checkuser())
1208  */
1209 static int
1210 checkaccess(const char *name)
1211 {
1212 
1213 	return (checkuser(_NAME_FTPUSERS, name, 1, 0, NULL));
1214 }
1215 
1216 static void
1217 login_utmp(const char *line, const char *name, const char *host,
1218     struct sockinet *haddr)
1219 {
1220 #if defined(SUPPORT_UTMPX) || defined(SUPPORT_UTMP)
1221 	struct timeval tv;
1222 	(void)gettimeofday(&tv, NULL);
1223 #endif
1224 #ifdef SUPPORT_UTMPX
1225 	if (doutmp) {
1226 		(void)memset(&utmpx, 0, sizeof(utmpx));
1227 		utmpx.ut_tv = tv;
1228 		utmpx.ut_pid = getpid();
1229 		utmpx.ut_id[0] = 'f';
1230 		utmpx.ut_id[1] = 't';
1231 		utmpx.ut_id[2] = 'p';
1232 		utmpx.ut_id[3] = '*';
1233 		utmpx.ut_type = USER_PROCESS;
1234 		(void)strncpy(utmpx.ut_name, name, sizeof(utmpx.ut_name));
1235 		(void)strncpy(utmpx.ut_line, line, sizeof(utmpx.ut_line));
1236 		(void)strncpy(utmpx.ut_host, host, sizeof(utmpx.ut_host));
1237 		(void)memcpy(&utmpx.ut_ss, &haddr->si_su, haddr->su_len);
1238 		ftpd_loginx(&utmpx);
1239 	}
1240 	if (dowtmp)
1241 		ftpd_logwtmpx(line, name, host, haddr, 0, USER_PROCESS);
1242 #endif
1243 #ifdef SUPPORT_UTMP
1244 	if (doutmp) {
1245 		(void)memset(&utmp, 0, sizeof(utmp));
1246 		(void)time(&utmp.ut_time);
1247 		(void)strncpy(utmp.ut_name, name, sizeof(utmp.ut_name));
1248 		(void)strncpy(utmp.ut_line, line, sizeof(utmp.ut_line));
1249 		(void)strncpy(utmp.ut_host, host, sizeof(utmp.ut_host));
1250 		ftpd_login(&utmp);
1251 	}
1252 	if (dowtmp)
1253 		ftpd_logwtmp(line, name, host);
1254 #endif
1255 }
1256 
1257 static void
1258 logout_utmp(void)
1259 {
1260 #ifdef SUPPORT_UTMPX
1261 	int okwtmpx = dowtmp;
1262 #endif
1263 #ifdef SUPPORT_UTMP
1264 	int okwtmp = dowtmp;
1265 #endif
1266 	if (logged_in) {
1267 #ifdef SUPPORT_UTMPX
1268 		if (doutmp)
1269 			okwtmpx &= ftpd_logoutx(ttyline, 0, DEAD_PROCESS);
1270 		if (okwtmpx)
1271 			ftpd_logwtmpx(ttyline, "", "", NULL, 0, DEAD_PROCESS);
1272 #endif
1273 #ifdef SUPPORT_UTMP
1274 		if (doutmp)
1275 			okwtmp &= ftpd_logout(ttyline);
1276 		if (okwtmp)
1277 			ftpd_logwtmp(ttyline, "", "");
1278 #endif
1279 	}
1280 }
1281 
1282 /*
1283  * Terminate login as previous user (if any), resetting state;
1284  * used when USER command is given or login fails.
1285  */
1286 static void
1287 end_login(void)
1288 {
1289 #ifdef USE_PAM
1290 	int e;
1291 #endif
1292 	logout_utmp();
1293 	show_chdir_messages(-1);		/* flush chdir cache */
1294 	if (pw != NULL && pw->pw_passwd != NULL)
1295 		memset(pw->pw_passwd, 0, strlen(pw->pw_passwd));
1296 	pw = NULL;
1297 	logged_in = 0;
1298 	askpasswd = 0;
1299 	permitted = 0;
1300 	quietmessages = 0;
1301 	gidcount = 0;
1302 	curclass.type = CLASS_REAL;
1303 	(void) seteuid((uid_t)0);
1304 #ifdef	LOGIN_CAP
1305 	setusercontext(NULL, getpwuid(0), 0,
1306 		       LOGIN_SETPRIORITY|LOGIN_SETRESOURCES|LOGIN_SETUMASK);
1307 #endif
1308 #ifdef USE_PAM
1309 	if (pamh) {
1310 		if ((e = pam_setcred(pamh, PAM_DELETE_CRED)) != PAM_SUCCESS)
1311 			syslog(LOG_ERR, "pam_setcred: %s",
1312 			    pam_strerror(pamh, e));
1313 		if ((e = pam_close_session(pamh,0)) != PAM_SUCCESS)
1314 			syslog(LOG_ERR, "pam_close_session: %s",
1315 			    pam_strerror(pamh, e));
1316 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS)
1317 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1318 		pamh = NULL;
1319 	}
1320 #endif
1321 }
1322 
1323 void
1324 pass(const char *passwd)
1325 {
1326 	do_pass(0, 0, passwd);
1327 }
1328 
1329 /*
1330  * Perform the passwd confirmation and login.
1331  *
1332  * If pass_checked is zero, confirm passwd is correct, & ignore pass_rval.
1333  * This is the traditional PASS implementation.
1334  *
1335  * If pass_checked is non-zero, use pass_rval and ignore passwd.
1336  * This is used by auth_pam() which has already parsed PASS.
1337  * This only applies to curclass.type != CLASS_GUEST.
1338  */
1339 static void
1340 do_pass(int pass_checked, int pass_rval, const char *passwd)
1341 {
1342 	int		 rval;
1343 	char		 root[MAXPATHLEN];
1344 #ifdef	LOGIN_CAP
1345 	login_cap_t *lc = NULL;
1346 #endif
1347 #ifdef USE_PAM
1348 	int e;
1349 #endif
1350 
1351 	rval = 1;
1352 
1353 	if (logged_in || askpasswd == 0) {
1354 		reply(503, "Login with USER first.");
1355 		return;
1356 	}
1357 	askpasswd = 0;
1358 	if (curclass.type != CLASS_GUEST) {
1359 			/* "ftp" is the only account allowed with no password */
1360 		if (pw == NULL) {
1361 			rval = 1;	/* failure below */
1362 			goto skip;
1363 		}
1364 		if (pass_checked) {	/* password validated in user() */
1365 			rval = pass_rval;
1366 			goto skip;
1367 		}
1368 #ifdef USE_PAM
1369 		syslog(LOG_ERR, "do_pass: USE_PAM shouldn't get here");
1370 		rval = 1;
1371 		goto skip;
1372 #endif
1373 #if defined(KERBEROS)
1374 		if (klogin(pw, "", hostname, (char *)passwd) == 0) {
1375 			rval = 0;
1376 			goto skip;
1377 		}
1378 #endif
1379 #if defined(KERBEROS5)
1380 		if (k5login(pw, "", hostname, (char *)passwd) == 0) {
1381 			rval = 0;
1382 			goto skip;
1383 		}
1384 #endif
1385 #ifdef SKEY
1386 		if (skey_haskey(pw->pw_name) == 0) {
1387 			char *p;
1388 			int r;
1389 
1390 			p = ftpd_strdup(passwd);
1391 			r = skey_passcheck(pw->pw_name, p);
1392 			free(p);
1393 			if (r != -1) {
1394 				rval = 0;
1395 				goto skip;
1396 			}
1397 		}
1398 #endif
1399 		if (!sflag)
1400 			rval = checkpassword(pw, passwd);
1401 		else
1402 			rval = 1;
1403 
1404  skip:
1405 
1406 			/*
1407 			 * If rval > 0, the user failed the authentication check
1408 			 * above.  If rval == 0, either Kerberos or local
1409 			 * authentication succeeded.
1410 			 */
1411 		if (rval) {
1412 			reply(530, "%s", rval == 2 ? "Password expired." :
1413 			    "Login incorrect.");
1414 			pfilter_notify(1, rval == 2 ? "exppass" : "badpass");
1415 			if (logging) {
1416 				syslog(LOG_NOTICE,
1417 				    "FTP LOGIN FAILED FROM %s", remoteloghost);
1418 				syslog(LOG_AUTHPRIV | LOG_NOTICE,
1419 				    "FTP LOGIN FAILED FROM %s, %s",
1420 				    remoteloghost, curname);
1421 			}
1422 			pw = NULL;
1423 			if (login_attempts++ >= 5) {
1424 				syslog(LOG_NOTICE,
1425 				    "repeated login failures from %s",
1426 				    remoteloghost);
1427 				exit(0);
1428 			}
1429 			return;
1430 		}
1431 	}
1432 
1433 			/* password ok; check if anything else prevents login */
1434 	if (! permitted) {
1435 		reply(530, "User %s may not use FTP.", pw->pw_name);
1436 		if (logging)
1437 			syslog(LOG_NOTICE, "FTP LOGIN REFUSED FROM %s, %s",
1438 			    remoteloghost, pw->pw_name);
1439 		goto bad;
1440 	}
1441 
1442 	login_attempts = 0;		/* this time successful */
1443 	if (setegid((gid_t)pw->pw_gid) < 0) {
1444 		reply(550, "Can't set gid.");
1445 		goto bad;
1446 	}
1447 #ifdef	LOGIN_CAP
1448 	if ((lc = login_getpwclass(pw)) != NULL) {
1449 #ifdef notyet
1450 		char	remote_ip[NI_MAXHOST];
1451 
1452 		if (getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
1453 			remote_ip, sizeof(remote_ip) - 1, NULL, 0,
1454 			NI_NUMERICHOST))
1455 				*remote_ip = 0;
1456 		remote_ip[sizeof(remote_ip) - 1] = 0;
1457 		if (!auth_hostok(lc, remotehost, remote_ip)) {
1458 			pfilter_notify(1, "bannedhost");
1459 			syslog(LOG_INFO|LOG_AUTH,
1460 			    "FTP LOGIN FAILED (HOST) as %s: permission denied.",
1461 			    pw->pw_name);
1462 			reply(530, "Permission denied.");
1463 			pw = NULL;
1464 			return;
1465 		}
1466 		if (!auth_timeok(lc, time(NULL))) {
1467 			reply(530, "Login not available right now.");
1468 			pw = NULL;
1469 			return;
1470 		}
1471 #endif
1472 	}
1473 	setsid();
1474 	setusercontext(lc, pw, 0,
1475 		LOGIN_SETLOGIN|LOGIN_SETGROUP|LOGIN_SETPRIORITY|
1476 		LOGIN_SETRESOURCES|LOGIN_SETUMASK);
1477 #else
1478 	(void) initgroups(pw->pw_name, pw->pw_gid);
1479 			/* cache groups for cmds.c::matchgroup() */
1480 #endif
1481 #ifdef USE_PAM
1482 	if (pamh) {
1483 		if ((e = pam_open_session(pamh, 0)) != PAM_SUCCESS) {
1484 			syslog(LOG_ERR, "pam_open_session: %s",
1485 			    pam_strerror(pamh, e));
1486 		} else if ((e = pam_setcred(pamh, PAM_ESTABLISH_CRED))
1487 		    != PAM_SUCCESS) {
1488 			syslog(LOG_ERR, "pam_setcred: %s",
1489 			    pam_strerror(pamh, e));
1490 		}
1491 	}
1492 #endif
1493 	gidcount = getgroups(0, NULL);
1494 	if (gidlist)
1495 		free(gidlist);
1496 	gidlist = malloc(gidcount * sizeof *gidlist);
1497 	gidcount = getgroups(gidcount, gidlist);
1498 
1499 	/* open utmp/wtmp before chroot */
1500 	login_utmp(ttyline, pw->pw_name, remotehost, &his_addr);
1501 
1502 	logged_in = 1;
1503 
1504 	connections = 1;
1505 	if (dopidfile)
1506 		count_users();
1507 	if (curclass.limit != -1 && connections > curclass.limit) {
1508 		if (! EMPTYSTR(curclass.limitfile))
1509 			(void)display_file(conffilename(curclass.limitfile),
1510 			    530);
1511 		reply(530,
1512 		    "User %s access denied, connection limit of " LLF
1513 		    " reached.",
1514 		    pw->pw_name, (LLT)curclass.limit);
1515 		syslog(LOG_NOTICE,
1516 		    "Maximum connection limit of " LLF
1517 		    " for class %s reached, login refused for %s",
1518 		    (LLT)curclass.limit, curclass.classname, pw->pw_name);
1519 		goto bad;
1520 	}
1521 
1522 	homedir[0] = '/';
1523 	switch (curclass.type) {
1524 	case CLASS_GUEST:
1525 			/*
1526 			 * We MUST do a chdir() after the chroot. Otherwise
1527 			 * the old current directory will be accessible as "."
1528 			 * outside the new root!
1529 			 */
1530 		format_path(root,
1531 		    curclass.chroot ? curclass.chroot :
1532 		    anondir ? anondir :
1533 		    pw->pw_dir);
1534 		format_path(homedir,
1535 		    curclass.homedir ? curclass.homedir :
1536 		    "/");
1537 		if (EMPTYSTR(homedir))
1538 			homedir[0] = '/';
1539 		if (EMPTYSTR(root) || chroot(root) < 0) {
1540 			syslog(LOG_NOTICE,
1541 			    "GUEST user %s: can't chroot to %s: %m",
1542 			    pw->pw_name, root);
1543 			goto bad_guest;
1544 		}
1545 		if (chdir(homedir) < 0) {
1546 			syslog(LOG_NOTICE,
1547 			    "GUEST user %s: can't chdir to %s: %m",
1548 			    pw->pw_name, homedir);
1549  bad_guest:
1550 			reply(550, "Can't set guest privileges.");
1551 			goto bad;
1552 		}
1553 		break;
1554 	case CLASS_CHROOT:
1555 		format_path(root,
1556 		    curclass.chroot ? curclass.chroot :
1557 		    pw->pw_dir);
1558 		format_path(homedir,
1559 		    curclass.homedir ? curclass.homedir :
1560 		    "/");
1561 		if (EMPTYSTR(homedir))
1562 			homedir[0] = '/';
1563 		if (EMPTYSTR(root) || chroot(root) < 0) {
1564 			syslog(LOG_NOTICE,
1565 			    "CHROOT user %s: can't chroot to %s: %m",
1566 			    pw->pw_name, root);
1567 			goto bad_chroot;
1568 		}
1569 		if (chdir(homedir) < 0) {
1570 			syslog(LOG_NOTICE,
1571 			    "CHROOT user %s: can't chdir to %s: %m",
1572 			    pw->pw_name, homedir);
1573  bad_chroot:
1574 			reply(550, "Can't change root.");
1575 			goto bad;
1576 		}
1577 		break;
1578 	case CLASS_REAL:
1579 			/* only chroot REAL if explicitly requested */
1580 		if (! EMPTYSTR(curclass.chroot)) {
1581 			format_path(root, curclass.chroot);
1582 			if (EMPTYSTR(root) || chroot(root) < 0) {
1583 				syslog(LOG_NOTICE,
1584 				    "REAL user %s: can't chroot to %s: %m",
1585 				    pw->pw_name, root);
1586 				goto bad_chroot;
1587 			}
1588 		}
1589 		format_path(homedir,
1590 		    curclass.homedir ? curclass.homedir :
1591 		    pw->pw_dir);
1592 		if (EMPTYSTR(homedir) || chdir(homedir) < 0) {
1593 			if (chdir("/") < 0) {
1594 				syslog(LOG_NOTICE,
1595 				    "REAL user %s: can't chdir to %s: %m",
1596 				    pw->pw_name,
1597 				    !EMPTYSTR(homedir) ?  homedir : "/");
1598 				reply(530,
1599 				    "User %s: can't change directory to %s.",
1600 				    pw->pw_name,
1601 				    !EMPTYSTR(homedir) ? homedir : "/");
1602 				goto bad;
1603 			} else {
1604 				reply(-230,
1605 				    "No directory! Logging in with home=/");
1606 				homedir[0] = '/';
1607 			}
1608 		}
1609 		break;
1610 	}
1611 #ifndef LOGIN_CAP
1612 	setsid();
1613 	setlogin(pw->pw_name);
1614 #endif
1615 	if (dropprivs ||
1616 	    (curclass.type != CLASS_REAL &&
1617 	    ntohs(ctrl_addr.su_port) > IPPORT_RESERVED + 1)) {
1618 		dropprivs++;
1619 		if (setgid((gid_t)pw->pw_gid) < 0) {
1620 			reply(550, "Can't set gid.");
1621 			goto bad;
1622 		}
1623 		if (setuid((uid_t)pw->pw_uid) < 0) {
1624 			reply(550, "Can't set uid.");
1625 			goto bad;
1626 		}
1627 	} else {
1628 		if (seteuid((uid_t)pw->pw_uid) < 0) {
1629 			reply(550, "Can't set uid.");
1630 			goto bad;
1631 		}
1632 	}
1633 	setenv("HOME", homedir, 1);
1634 
1635 	if (curclass.type == CLASS_GUEST && passwd[0] == '-')
1636 		quietmessages = 1;
1637 
1638 			/*
1639 			 * Display a login message, if it exists.
1640 			 * N.B. reply(230,) must follow the message.
1641 			 */
1642 	if (! EMPTYSTR(curclass.motd))
1643 		(void)display_file(conffilename(curclass.motd), 230);
1644 	show_chdir_messages(230);
1645 	if (curclass.type == CLASS_GUEST) {
1646 		char *p;
1647 
1648 		reply(230, "Guest login ok, access restrictions apply.");
1649 #if defined(HAVE_SETPROCTITLE)
1650 		snprintf(proctitle, sizeof(proctitle),
1651 		    "%s: anonymous/%s", remotehost, passwd);
1652 		setproctitle("%s", proctitle);
1653 #endif /* defined(HAVE_SETPROCTITLE) */
1654 		if (logging)
1655 			syslog(LOG_INFO,
1656 			"ANONYMOUS FTP LOGIN FROM %s, %s (class: %s, type: %s)",
1657 			    remoteloghost, passwd,
1658 			    curclass.classname, CURCLASSTYPE);
1659 			/* store guest password reply into pw_passwd */
1660 		REASSIGN(pw->pw_passwd, ftpd_strdup(passwd));
1661 		for (p = pw->pw_passwd; *p; p++)
1662 			if (!isgraph((unsigned char)*p))
1663 				*p = '_';
1664 	} else {
1665 		reply(230, "User %s logged in.", pw->pw_name);
1666 #if defined(HAVE_SETPROCTITLE)
1667 		snprintf(proctitle, sizeof(proctitle),
1668 		    "%s: %s", remotehost, pw->pw_name);
1669 		setproctitle("%s", proctitle);
1670 #endif /* defined(HAVE_SETPROCTITLE) */
1671 		if (logging)
1672 			syslog(LOG_INFO,
1673 			    "FTP LOGIN FROM %s as %s (class: %s, type: %s)",
1674 			    remoteloghost, pw->pw_name,
1675 			    curclass.classname, CURCLASSTYPE);
1676 	}
1677 	(void) umask(curclass.umask);
1678 #ifdef	LOGIN_CAP
1679 	login_close(lc);
1680 #endif
1681 	return;
1682 
1683  bad:
1684 #ifdef	LOGIN_CAP
1685 	login_close(lc);
1686 #endif
1687 			/* Forget all about it... */
1688 	end_login();
1689 }
1690 
1691 void
1692 retrieve(const char *argv[], const char *name)
1693 {
1694 	FILE *fin, *dout;
1695 	struct stat st;
1696 	int (*closefunc)(FILE *) = NULL;
1697 	int dolog, sendrv, closerv, stderrfd, isconversion, isdata, isls;
1698 	struct timeval start, finish, td, *tdp;
1699 	struct rusage rusage_before, rusage_after;
1700 	const char *dispname;
1701 	const char *error;
1702 
1703 	sendrv = closerv = stderrfd = -1;
1704 	isconversion = isdata = isls = dolog = 0;
1705 	tdp = NULL;
1706 	dispname = name;
1707 	fin = dout = NULL;
1708 	error = NULL;
1709 	if (argv == NULL) {		/* if not running a command ... */
1710 		dolog = 1;
1711 		isdata = 1;
1712 		fin = fopen(name, "r");
1713 		closefunc = fclose;
1714 		if (fin == NULL)	/* doesn't exist?; try a conversion */
1715 			argv = do_conversion(name);
1716 		if (argv != NULL) {
1717 			isconversion++;
1718 			syslog(LOG_DEBUG, "get command: '%s' on '%s'",
1719 			    argv[0], name);
1720 		}
1721 	}
1722 	if (argv != NULL) {
1723 		char temp[MAXPATHLEN];
1724 
1725 		if (strcmp(argv[0], INTERNAL_LS) == 0) {
1726 			isls = 1;
1727 			stderrfd = -1;
1728 		} else {
1729 			(void)snprintf(temp, sizeof(temp), "%s", TMPFILE);
1730 			stderrfd = mkstemp(temp);
1731 			if (stderrfd != -1)
1732 				(void)unlink(temp);
1733 		}
1734 		dispname = argv[0];
1735 		fin = ftpd_popen(argv, "r", stderrfd);
1736 		closefunc = ftpd_pclose;
1737 		st.st_size = -1;
1738 		st.st_blksize = BUFSIZ;
1739 	}
1740 	if (fin == NULL) {
1741 		if (errno != 0) {
1742 			perror_reply(550, dispname);
1743 			if (dolog)
1744 				logxfer("get", -1, name, NULL, NULL,
1745 				    strerror(errno));
1746 		}
1747 		goto cleanupretrieve;
1748 	}
1749 	byte_count = -1;
1750 	if (argv == NULL
1751 	    && (fstat(fileno(fin), &st) < 0 || !S_ISREG(st.st_mode))) {
1752 		error = "Not a plain file";
1753 		reply(550, "%s: %s.", dispname, error);
1754 		goto done;
1755 	}
1756 	if (restart_point) {
1757 		if (type == TYPE_A) {
1758 			off_t i;
1759 			int c;
1760 
1761 			for (i = 0; i < restart_point; i++) {
1762 				if ((c=getc(fin)) == EOF) {
1763 					error = strerror(errno);
1764 					perror_reply(550, dispname);
1765 					goto done;
1766 				}
1767 				if (c == '\n')
1768 					i++;
1769 			}
1770 		} else if (lseek(fileno(fin), restart_point, SEEK_SET) < 0) {
1771 			error = strerror(errno);
1772 			perror_reply(550, dispname);
1773 			goto done;
1774 		}
1775 	}
1776 	dout = dataconn(dispname, st.st_size, "w");
1777 	if (dout == NULL)
1778 		goto done;
1779 
1780 	(void)getrusage(RUSAGE_SELF, &rusage_before);
1781 	(void)gettimeofday(&start, NULL);
1782 	sendrv = send_data(fin, dout, &st, isdata);
1783 	(void)gettimeofday(&finish, NULL);
1784 	(void)getrusage(RUSAGE_SELF, &rusage_after);
1785 	closedataconn(dout);		/* close now to affect timing stats */
1786 	timersub(&finish, &start, &td);
1787 	tdp = &td;
1788  done:
1789 	if (dolog) {
1790 		logxfer("get", byte_count, name, NULL, tdp, error);
1791 		if (tdp != NULL)
1792 			logrusage(&rusage_before, &rusage_after);
1793 	}
1794 	closerv = (*closefunc)(fin);
1795 	if (sendrv == 0) {
1796 		FILE *errf;
1797 		struct stat sb;
1798 
1799 		if (!isls && argv != NULL && closerv != 0) {
1800 			reply(-226,
1801 			    "Command returned an exit status of %d",
1802 			    closerv);
1803 			if (isconversion)
1804 				syslog(LOG_WARNING,
1805 				    "retrieve command: '%s' returned %d",
1806 				    argv[0], closerv);
1807 		}
1808 		if (!isls && argv != NULL && stderrfd != -1 &&
1809 		    (fstat(stderrfd, &sb) == 0) && sb.st_size > 0 &&
1810 		    ((errf = fdopen(stderrfd, "r")) != NULL)) {
1811 			char *cp, line[LINE_MAX];
1812 
1813 			reply(-226, "Command error messages:");
1814 			rewind(errf);
1815 			while (fgets(line, sizeof(line), errf) != NULL) {
1816 				if ((cp = strchr(line, '\n')) != NULL)
1817 					*cp = '\0';
1818 				reply(0, "  %s", line);
1819 			}
1820 			(void) fflush(stdout);
1821 			(void) fclose(errf);
1822 				/* a reply(226,) must follow */
1823 		}
1824 		reply(226, "Transfer complete.");
1825 	}
1826  cleanupretrieve:
1827 	if (stderrfd != -1)
1828 		(void)close(stderrfd);
1829 	if (isconversion)
1830 		free(argv);
1831 }
1832 
1833 void
1834 store(const char *name, const char *fmode, int unique)
1835 {
1836 	FILE *fout, *din;
1837 	struct stat st;
1838 	int (*closefunc)(FILE *);
1839 	struct timeval start, finish, td, *tdp;
1840 	const char *desc, *error;
1841 
1842 	din = NULL;
1843 	desc = (*fmode == 'w') ? "put" : "append";
1844 	error = NULL;
1845 	if (unique && stat(name, &st) == 0 &&
1846 	    (name = gunique(name)) == NULL) {
1847 		logxfer(desc, -1, name, NULL, NULL,
1848 		    "cannot create unique file");
1849 		goto cleanupstore;
1850 	}
1851 
1852 	if (restart_point)
1853 		fmode = "r+";
1854 	fout = fopen(name, fmode);
1855 	closefunc = fclose;
1856 	tdp = NULL;
1857 	if (fout == NULL) {
1858 		perror_reply(553, name);
1859 		logxfer(desc, -1, name, NULL, NULL, strerror(errno));
1860 		goto cleanupstore;
1861 	}
1862 	byte_count = -1;
1863 	if (restart_point) {
1864 		if (type == TYPE_A) {
1865 			off_t i;
1866 			int c;
1867 
1868 			for (i = 0; i < restart_point; i++) {
1869 				if ((c=getc(fout)) == EOF) {
1870 					error = strerror(errno);
1871 					perror_reply(550, name);
1872 					goto done;
1873 				}
1874 				if (c == '\n')
1875 					i++;
1876 			}
1877 			/*
1878 			 * We must do this seek to "current" position
1879 			 * because we are changing from reading to
1880 			 * writing.
1881 			 */
1882 			if (fseek(fout, 0L, SEEK_CUR) < 0) {
1883 				error = strerror(errno);
1884 				perror_reply(550, name);
1885 				goto done;
1886 			}
1887 		} else if (lseek(fileno(fout), restart_point, SEEK_SET) < 0) {
1888 			error = strerror(errno);
1889 			perror_reply(550, name);
1890 			goto done;
1891 		}
1892 	}
1893 	din = dataconn(name, (off_t)-1, "r");
1894 	if (din == NULL)
1895 		goto done;
1896 	(void)gettimeofday(&start, NULL);
1897 	if (receive_data(din, fout) == 0) {
1898 		if (unique)
1899 			reply(226, "Transfer complete (unique file name:%s).",
1900 			    name);
1901 		else
1902 			reply(226, "Transfer complete.");
1903 	}
1904 	(void)gettimeofday(&finish, NULL);
1905 	closedataconn(din);		/* close now to affect timing stats */
1906 	timersub(&finish, &start, &td);
1907 	tdp = &td;
1908  done:
1909 	logxfer(desc, byte_count, name, NULL, tdp, error);
1910 	(*closefunc)(fout);
1911  cleanupstore:
1912 	;
1913 }
1914 
1915 static FILE *
1916 getdatasock(const char *fmode)
1917 {
1918 	int		on, s, t, tries;
1919 	in_port_t	port;
1920 
1921 	on = 1;
1922 	if (data >= 0)
1923 		return (fdopen(data, fmode));
1924 	if (! dropprivs)
1925 		(void) seteuid((uid_t)0);
1926 	s = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
1927 	if (s < 0)
1928 		goto bad;
1929 	if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR,
1930 	    (char *) &on, sizeof(on)) < 0)
1931 		goto bad;
1932 	if (setsockopt(s, SOL_SOCKET, SO_KEEPALIVE,
1933 	    (char *) &on, sizeof(on)) < 0)
1934 		goto bad;
1935 			/* anchor socket to avoid multi-homing problems */
1936 	data_source = ctrl_addr;
1937 			/*
1938 			 * By default source port for PORT connctions is
1939 			 * ctrlport-1 (see RFC959 section 5.2).
1940 			 * However, if privs have been dropped and that
1941 			 * would be < IPPORT_RESERVED, use a random port
1942 			 * instead.
1943 			 */
1944 	if (dataport)
1945 		port = dataport;
1946 	else
1947 		port = ntohs(ctrl_addr.su_port) - 1;
1948 	if (dropprivs && port < IPPORT_RESERVED)
1949 		port = 0;		/* use random port */
1950 	data_source.su_port = htons(port);
1951 
1952 	for (tries = 1; ; tries++) {
1953 		if (bind(s, (struct sockaddr *)&data_source.si_su,
1954 		    data_source.su_len) >= 0)
1955 			break;
1956 		if (errno != EADDRINUSE || tries > 10)
1957 			goto bad;
1958 		sleep(tries);
1959 	}
1960 	if (! dropprivs)
1961 		(void) seteuid((uid_t)pw->pw_uid);
1962 #ifdef IP_TOS
1963 	if (!mapped && ctrl_addr.su_family == AF_INET) {
1964 		on = IPTOS_THROUGHPUT;
1965 		if (setsockopt(s, IPPROTO_IP, IP_TOS, (char *)&on,
1966 			       sizeof(int)) < 0)
1967 			syslog(LOG_WARNING, "setsockopt (IP_TOS): %m");
1968 	}
1969 #endif
1970 	return (fdopen(s, fmode));
1971  bad:
1972 		/* Return the real value of errno (close may change it) */
1973 	t = errno;
1974 	if (! dropprivs)
1975 		(void) seteuid((uid_t)pw->pw_uid);
1976 	if (s >= 0)
1977 		(void) close(s);
1978 	errno = t;
1979 	return (NULL);
1980 }
1981 
1982 FILE *
1983 dataconn(const char *name, off_t size, const char *fmode)
1984 {
1985 	char sizebuf[32];
1986 	FILE *file;
1987 	int retry, tos, keepalive, conerrno;
1988 
1989 	file_size = size;
1990 	byte_count = 0;
1991 	if (size != (off_t) -1)
1992 		(void)snprintf(sizebuf, sizeof(sizebuf), " (" LLF " byte%s)",
1993 		    (LLT)size, PLURAL(size));
1994 	else
1995 		sizebuf[0] = '\0';
1996 	if (pdata >= 0) {
1997 		struct sockinet from;
1998 		int s;
1999 		socklen_t fromlen = sizeof(from.su_len);
2000 
2001 		(void) alarm(curclass.timeout);
2002 		s = accept(pdata, (struct sockaddr *)&from.si_su, &fromlen);
2003 		(void) alarm(0);
2004 		if (s < 0) {
2005 			reply(425, "Can't open data connection.");
2006 			(void) close(pdata);
2007 			pdata = -1;
2008 			return (NULL);
2009 		}
2010 		(void) close(pdata);
2011 		pdata = s;
2012 		switch (from.su_family) {
2013 		case AF_INET:
2014 #ifdef IP_TOS
2015 			if (!mapped) {
2016 				tos = IPTOS_THROUGHPUT;
2017 				(void) setsockopt(s, IPPROTO_IP, IP_TOS,
2018 				    (char *)&tos, sizeof(int));
2019 			}
2020 			break;
2021 #endif
2022 		}
2023 		/* Set keepalives on the socket to detect dropped conns. */
2024 #ifdef SO_KEEPALIVE
2025 		keepalive = 1;
2026 		(void) setsockopt(s, SOL_SOCKET, SO_KEEPALIVE,
2027 		    (char *)&keepalive, sizeof(int));
2028 #endif
2029 		reply(150, "Opening %s mode data connection for '%s'%s.",
2030 		     type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
2031 		return (fdopen(pdata, fmode));
2032 	}
2033 	if (data >= 0) {
2034 		reply(125, "Using existing data connection for '%s'%s.",
2035 		    name, sizebuf);
2036 		usedefault = 1;
2037 		return (fdopen(data, fmode));
2038 	}
2039 	if (usedefault)
2040 		data_dest = his_addr;
2041 	usedefault = 1;
2042 	retry = conerrno = 0;
2043 	do {
2044 		file = getdatasock(fmode);
2045 		if (file == NULL) {
2046 			char hbuf[NI_MAXHOST];
2047 			char pbuf[NI_MAXSERV];
2048 
2049 			if (getnameinfo((struct sockaddr *)&data_source.si_su,
2050 			    data_source.su_len, hbuf, sizeof(hbuf), pbuf,
2051 			    sizeof(pbuf), NI_NUMERICHOST | NI_NUMERICSERV))
2052 				strlcpy(hbuf, "?", sizeof(hbuf));
2053 			reply(425, "Can't create data socket (%s,%s): %s.",
2054 			      hbuf, pbuf, strerror(errno));
2055 			return (NULL);
2056 		}
2057 		data = fileno(file);
2058 		conerrno = 0;
2059 		if (connect(data, (struct sockaddr *)&data_dest.si_su,
2060 		    data_dest.su_len) == 0)
2061 			break;
2062 		conerrno = errno;
2063 		(void) fclose(file);
2064 		file = NULL;
2065 		data = -1;
2066 		if (conerrno == EADDRINUSE) {
2067 			sleep((unsigned) swaitint);
2068 			retry += swaitint;
2069 		} else {
2070 			break;
2071 		}
2072 	} while (retry <= swaitmax);
2073 	if (conerrno != 0) {
2074 		perror_reply(425, "Can't build data connection");
2075 		return (NULL);
2076 	}
2077 	reply(150, "Opening %s mode data connection for '%s'%s.",
2078 	     type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
2079 	return (file);
2080 }
2081 
2082 void
2083 closedataconn(FILE *fd)
2084 {
2085 
2086 	if (fd == NULL)
2087 		return;
2088 	(void)fclose(fd);
2089 	data = -1;
2090 	if (pdata >= 0)
2091 		(void)close(pdata);
2092 	pdata = -1;
2093 }
2094 
2095 int
2096 write_data(int fd, char *buf, size_t size, off_t *bufrem,
2097     struct timeval *then, int isdata)
2098 {
2099 	struct timeval now, td;
2100 	ssize_t c;
2101 
2102 	while (size > 0) {
2103 		c = size;
2104 		if (curclass.writesize) {
2105 			if (curclass.writesize < c)
2106 				c = curclass.writesize;
2107 		}
2108 		if (curclass.rateget) {
2109 			if (*bufrem < c)
2110 				c = *bufrem;
2111 		}
2112 		(void) alarm(curclass.timeout);
2113 		c = write(fd, buf, c);
2114 		if (c <= 0)
2115 			return (1);
2116 		buf += c;
2117 		size -= c;
2118 		byte_count += c;
2119 		if (isdata) {
2120 			total_data_out += c;
2121 			total_data += c;
2122 		}
2123 		total_bytes_out += c;
2124 		total_bytes += c;
2125 		if (curclass.rateget) {
2126 			*bufrem -= c;
2127 			if (*bufrem == 0) {
2128 				(void)gettimeofday(&now, NULL);
2129 				timersub(&now, then, &td);
2130 				if (td.tv_sec == 0) {
2131 					usleep(1000000 - td.tv_usec);
2132 					(void)gettimeofday(then, NULL);
2133 				} else
2134 					*then = now;
2135 				*bufrem = curclass.rateget;
2136 			}
2137 		}
2138 	}
2139 	return (0);
2140 }
2141 
2142 static enum send_status
2143 send_data_with_read(int filefd, int netfd, const struct stat *st, int isdata)
2144 {
2145 	struct timeval then;
2146 	off_t bufrem;
2147 	ssize_t readsize;
2148 	char *buf;
2149 	int c, error;
2150 
2151 	if (curclass.readsize > 0)
2152 		readsize = curclass.readsize;
2153 	else
2154 		readsize = st->st_blksize;
2155 	if ((buf = malloc(readsize)) == NULL) {
2156 		perror_reply(451, "Local resource failure: malloc");
2157 		return (SS_NO_TRANSFER);
2158 	}
2159 
2160 	if (curclass.rateget) {
2161 		bufrem = curclass.rateget;
2162 		(void)gettimeofday(&then, NULL);
2163 	} else
2164 		bufrem = readsize;
2165 	for (;;) {
2166 		(void) alarm(curclass.timeout);
2167 		c = read(filefd, buf, readsize);
2168 		if (c == 0)
2169 			error = SS_SUCCESS;
2170 		else if (c < 0)
2171 			error = SS_FILE_ERROR;
2172 		else if (write_data(netfd, buf, c, &bufrem, &then, isdata))
2173 			error = SS_DATA_ERROR;
2174 		else if (urgflag && handleoobcmd())
2175 			error = SS_ABORTED;
2176 		else
2177 			continue;
2178 
2179 		free(buf);
2180 		return (error);
2181 	}
2182 }
2183 
2184 static enum send_status
2185 send_data_with_mmap(int filefd, int netfd, const struct stat *st, int isdata)
2186 {
2187 	struct timeval then;
2188 	off_t bufrem, filesize, off, origoff;
2189 	ssize_t mapsize, winsize;
2190 	int error, sendbufsize, sendlowat;
2191 	void *win;
2192 
2193 	bufrem = 0;
2194 	if (curclass.sendbufsize) {
2195 		sendbufsize = curclass.sendbufsize;
2196 		if (setsockopt(netfd, SOL_SOCKET, SO_SNDBUF,
2197 		    &sendbufsize, sizeof(int)) == -1)
2198 			syslog(LOG_WARNING, "setsockopt(SO_SNDBUF, %d): %m",
2199 			    sendbufsize);
2200 	}
2201 
2202 	if (curclass.sendlowat) {
2203 		sendlowat = curclass.sendlowat;
2204 		if (setsockopt(netfd, SOL_SOCKET, SO_SNDLOWAT,
2205 		    &sendlowat, sizeof(int)) == -1)
2206 			syslog(LOG_WARNING, "setsockopt(SO_SNDLOWAT, %d): %m",
2207 			    sendlowat);
2208 	}
2209 
2210 	winsize = curclass.mmapsize;
2211 	filesize = st->st_size;
2212 	if (ftpd_debug)
2213 		syslog(LOG_INFO, "mmapsize = " LLF ", writesize = " LLF,
2214 		    (LLT)winsize, (LLT)curclass.writesize);
2215 	if (winsize <= 0)
2216 		goto try_read;
2217 
2218 	off = lseek(filefd, (off_t)0, SEEK_CUR);
2219 	if (off == -1)
2220 		goto try_read;
2221 
2222 	origoff = off;
2223 	if (curclass.rateget) {
2224 		bufrem = curclass.rateget;
2225 		(void)gettimeofday(&then, NULL);
2226 	} else
2227 		bufrem = winsize;
2228 	while (1) {
2229 		mapsize = MIN(filesize - off, winsize);
2230 		if (mapsize == 0)
2231 			break;
2232 		win = mmap(NULL, mapsize, PROT_READ,
2233 		    MAP_FILE|MAP_SHARED, filefd, off);
2234 		if (win == MAP_FAILED) {
2235 			if (off == origoff)
2236 				goto try_read;
2237 			return (SS_FILE_ERROR);
2238 		}
2239 		(void) madvise(win, mapsize, MADV_SEQUENTIAL);
2240 		error = write_data(netfd, win, mapsize, &bufrem, &then,
2241 		    isdata);
2242 		(void) madvise(win, mapsize, MADV_DONTNEED);
2243 		munmap(win, mapsize);
2244 		if (urgflag && handleoobcmd())
2245 			return (SS_ABORTED);
2246 		if (error)
2247 			return (SS_DATA_ERROR);
2248 		off += mapsize;
2249 	}
2250 	return (SS_SUCCESS);
2251 
2252  try_read:
2253 	return (send_data_with_read(filefd, netfd, st, isdata));
2254 }
2255 
2256 /*
2257  * Transfer the contents of "instr" to "outstr" peer using the appropriate
2258  * encapsulation of the data subject to Mode, Structure, and Type.
2259  *
2260  * NB: Form isn't handled.
2261  */
2262 static int
2263 send_data(FILE *instr, FILE *outstr, const struct stat *st, int isdata)
2264 {
2265 	int	 c, filefd, netfd, rval;
2266 
2267 	urgflag = 0;
2268 	transflag = 1;
2269 	rval = -1;
2270 
2271 	switch (type) {
2272 
2273 	case TYPE_A:
2274  /* XXXLUKEM: rate limit ascii send (get) */
2275 		(void) alarm(curclass.timeout);
2276 		while ((c = getc(instr)) != EOF) {
2277 			if (urgflag && handleoobcmd())
2278 				goto cleanup_send_data;
2279 			byte_count++;
2280 			if (c == '\n') {
2281 				if (ferror(outstr))
2282 					goto data_err;
2283 				(void) putc('\r', outstr);
2284 				if (isdata) {
2285 					total_data_out++;
2286 					total_data++;
2287 				}
2288 				total_bytes_out++;
2289 				total_bytes++;
2290 			}
2291 			(void) putc(c, outstr);
2292 			if (isdata) {
2293 				total_data_out++;
2294 				total_data++;
2295 			}
2296 			total_bytes_out++;
2297 			total_bytes++;
2298 			if ((byte_count % 4096) == 0)
2299 				(void) alarm(curclass.timeout);
2300 		}
2301 		(void) alarm(0);
2302 		fflush(outstr);
2303 		if (ferror(instr))
2304 			goto file_err;
2305 		if (ferror(outstr))
2306 			goto data_err;
2307 		rval = 0;
2308 		goto cleanup_send_data;
2309 
2310 	case TYPE_I:
2311 	case TYPE_L:
2312 		filefd = fileno(instr);
2313 		netfd = fileno(outstr);
2314 		switch (send_data_with_mmap(filefd, netfd, st, isdata)) {
2315 
2316 		case SS_SUCCESS:
2317 			break;
2318 
2319 		case SS_ABORTED:
2320 		case SS_NO_TRANSFER:
2321 			goto cleanup_send_data;
2322 
2323 		case SS_FILE_ERROR:
2324 			goto file_err;
2325 
2326 		case SS_DATA_ERROR:
2327 			goto data_err;
2328 		}
2329 		rval = 0;
2330 		goto cleanup_send_data;
2331 
2332 	default:
2333 		reply(550, "Unimplemented TYPE %d in send_data", type);
2334 		goto cleanup_send_data;
2335 	}
2336 
2337  data_err:
2338 	(void) alarm(0);
2339 	perror_reply(426, "Data connection");
2340 	goto cleanup_send_data;
2341 
2342  file_err:
2343 	(void) alarm(0);
2344 	perror_reply(551, "Error on input file");
2345 	goto cleanup_send_data;
2346 
2347  cleanup_send_data:
2348 	(void) alarm(0);
2349 	transflag = 0;
2350 	urgflag = 0;
2351 	if (isdata) {
2352 		total_files_out++;
2353 		total_files++;
2354 	}
2355 	total_xfers_out++;
2356 	total_xfers++;
2357 	return (rval);
2358 }
2359 
2360 /*
2361  * Transfer data from peer to "outstr" using the appropriate encapulation of
2362  * the data subject to Mode, Structure, and Type.
2363  *
2364  * N.B.: Form isn't handled.
2365  */
2366 static int
2367 receive_data(FILE *instr, FILE *outstr)
2368 {
2369 	int	c, netfd, filefd, rval;
2370 	int	volatile bare_lfs;
2371 	off_t	byteswritten;
2372 	char	*buf;
2373 	ssize_t	readsize;
2374 	struct sigaction sa, sa_saved;
2375 	struct stat st;
2376 
2377 	memset(&sa, 0, sizeof(sa));
2378 	sigfillset(&sa.sa_mask);
2379 	sa.sa_flags = SA_RESTART;
2380 	sa.sa_handler = lostconn;
2381 	(void) sigaction(SIGALRM, &sa, &sa_saved);
2382 
2383 	bare_lfs = 0;
2384 	urgflag = 0;
2385 	transflag = 1;
2386 	rval = -1;
2387 	byteswritten = 0;
2388 	buf = NULL;
2389 
2390 #define FILESIZECHECK(x) \
2391 			do { \
2392 				if (curclass.maxfilesize != -1 && \
2393 				    (x) > curclass.maxfilesize) { \
2394 					errno = EFBIG; \
2395 					goto file_err; \
2396 				} \
2397 			} while (0)
2398 
2399 	switch (type) {
2400 
2401 	case TYPE_I:
2402 	case TYPE_L:
2403 		netfd = fileno(instr);
2404 		filefd = fileno(outstr);
2405 		(void) alarm(curclass.timeout);
2406 		if (curclass.readsize)
2407 			readsize = curclass.readsize;
2408 		else if (fstat(filefd, &st) != -1)
2409 			readsize = (ssize_t)st.st_blksize;
2410 		else
2411 			readsize = BUFSIZ;
2412 		if ((buf = malloc(readsize)) == NULL) {
2413 			perror_reply(451, "Local resource failure: malloc");
2414 			goto cleanup_recv_data;
2415 		}
2416 		if (curclass.rateput) {
2417 			while (1) {
2418 				int d;
2419 				struct timeval then, now, td;
2420 				off_t bufrem;
2421 
2422 				(void)gettimeofday(&then, NULL);
2423 				errno = c = d = 0;
2424 				for (bufrem = curclass.rateput; bufrem > 0; ) {
2425 					if ((c = read(netfd, buf,
2426 					    MIN(readsize, bufrem))) <= 0)
2427 						goto recvdone;
2428 					if (urgflag && handleoobcmd())
2429 						goto cleanup_recv_data;
2430 					FILESIZECHECK(byte_count + c);
2431 					if ((d = write(filefd, buf, c)) != c)
2432 						goto file_err;
2433 					(void) alarm(curclass.timeout);
2434 					bufrem -= c;
2435 					byte_count += c;
2436 					total_data_in += c;
2437 					total_data += c;
2438 					total_bytes_in += c;
2439 					total_bytes += c;
2440 				}
2441 				(void)gettimeofday(&now, NULL);
2442 				timersub(&now, &then, &td);
2443 				if (td.tv_sec == 0)
2444 					usleep(1000000 - td.tv_usec);
2445 			}
2446 		} else {
2447 			while ((c = read(netfd, buf, readsize)) > 0) {
2448 				if (urgflag && handleoobcmd())
2449 					goto cleanup_recv_data;
2450 				FILESIZECHECK(byte_count + c);
2451 				if (write(filefd, buf, c) != c)
2452 					goto file_err;
2453 				(void) alarm(curclass.timeout);
2454 				byte_count += c;
2455 				total_data_in += c;
2456 				total_data += c;
2457 				total_bytes_in += c;
2458 				total_bytes += c;
2459 			}
2460 		}
2461  recvdone:
2462 		if (c < 0)
2463 			goto data_err;
2464 		rval = 0;
2465 		goto cleanup_recv_data;
2466 
2467 	case TYPE_E:
2468 		reply(553, "TYPE E not implemented.");
2469 		goto cleanup_recv_data;
2470 
2471 	case TYPE_A:
2472 		(void) alarm(curclass.timeout);
2473  /* XXXLUKEM: rate limit ascii receive (put) */
2474 		while ((c = getc(instr)) != EOF) {
2475 			if (urgflag && handleoobcmd())
2476 				goto cleanup_recv_data;
2477 			byte_count++;
2478 			total_data_in++;
2479 			total_data++;
2480 			total_bytes_in++;
2481 			total_bytes++;
2482 			if ((byte_count % 4096) == 0)
2483 				(void) alarm(curclass.timeout);
2484 			if (c == '\n')
2485 				bare_lfs++;
2486 			while (c == '\r') {
2487 				if (ferror(outstr))
2488 					goto data_err;
2489 				if ((c = getc(instr)) != '\n') {
2490 					byte_count++;
2491 					total_data_in++;
2492 					total_data++;
2493 					total_bytes_in++;
2494 					total_bytes++;
2495 					if ((byte_count % 4096) == 0)
2496 						(void) alarm(curclass.timeout);
2497 					byteswritten++;
2498 					FILESIZECHECK(byteswritten);
2499 					(void) putc ('\r', outstr);
2500 					if (c == '\0' || c == EOF)
2501 						goto contin2;
2502 				}
2503 			}
2504 			byteswritten++;
2505 			FILESIZECHECK(byteswritten);
2506 			(void) putc(c, outstr);
2507  contin2:	;
2508 		}
2509 		(void) alarm(0);
2510 		fflush(outstr);
2511 		if (ferror(instr))
2512 			goto data_err;
2513 		if (ferror(outstr))
2514 			goto file_err;
2515 		if (bare_lfs) {
2516 			reply(-226,
2517 			    "WARNING! %d bare linefeeds received in ASCII mode",
2518 			    bare_lfs);
2519 			reply(0, "File may not have transferred correctly.");
2520 		}
2521 		rval = 0;
2522 		goto cleanup_recv_data;
2523 
2524 	default:
2525 		reply(550, "Unimplemented TYPE %d in receive_data", type);
2526 		goto cleanup_recv_data;
2527 	}
2528 #undef FILESIZECHECK
2529 
2530  data_err:
2531 	(void) alarm(0);
2532 	perror_reply(426, "Data Connection");
2533 	goto cleanup_recv_data;
2534 
2535  file_err:
2536 	(void) alarm(0);
2537 	perror_reply(452, "Error writing file");
2538 	goto cleanup_recv_data;
2539 
2540  cleanup_recv_data:
2541 	(void) alarm(0);
2542 	(void) sigaction(SIGALRM, &sa_saved, NULL);
2543 	if (buf)
2544 		free(buf);
2545 	transflag = 0;
2546 	urgflag = 0;
2547 	total_files_in++;
2548 	total_files++;
2549 	total_xfers_in++;
2550 	total_xfers++;
2551 	return (rval);
2552 }
2553 
2554 void
2555 statcmd(void)
2556 {
2557 	struct sockinet *su = NULL;
2558 	static char hbuf[NI_MAXHOST], sbuf[NI_MAXSERV];
2559 	unsigned char *a, *p;
2560 	int ispassive, af;
2561 	off_t otbi, otbo, otb;
2562 
2563 	a = p = NULL;
2564 
2565 	reply(-211, "%s FTP server status:", hostname);
2566 	reply(0, "Version: %s", EMPTYSTR(version) ? "<suppressed>" : version);
2567 	hbuf[0] = '\0';
2568 	if (!getnameinfo((struct sockaddr *)&his_addr.si_su, his_addr.su_len,
2569 			hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST)
2570 	    && strcmp(remotehost, hbuf) != 0)
2571 		reply(0, "Connected to %s (%s)", remotehost, hbuf);
2572 	else
2573 		reply(0, "Connected to %s", remotehost);
2574 
2575 	if (logged_in) {
2576 		if (curclass.type == CLASS_GUEST)
2577 			reply(0, "Logged in anonymously");
2578 		else
2579 			reply(0, "Logged in as %s%s", pw->pw_name,
2580 			    curclass.type == CLASS_CHROOT ? " (chroot)" : "");
2581 	} else if (askpasswd)
2582 		reply(0, "Waiting for password");
2583 	else
2584 		reply(0, "Waiting for user name");
2585 	cprintf(stdout, "    TYPE: %s", typenames[type]);
2586 	if (type == TYPE_A || type == TYPE_E)
2587 		cprintf(stdout, ", FORM: %s", formnames[form]);
2588 	if (type == TYPE_L) {
2589 #if NBBY == 8
2590 		cprintf(stdout, " %d", NBBY);
2591 #else
2592 			/* XXX: `bytesize' needs to be defined in this case */
2593 		cprintf(stdout, " %d", bytesize);
2594 #endif
2595 	}
2596 	cprintf(stdout, "; STRUcture: %s; transfer MODE: %s\r\n",
2597 	    strunames[stru], modenames[mode]);
2598 	ispassive = 0;
2599 	if (data != -1) {
2600 		reply(0, "Data connection open");
2601 		su = NULL;
2602 	} else if (pdata != -1) {
2603 		reply(0, "in Passive mode");
2604 		if (curclass.advertise.su_len != 0)
2605 			su = &curclass.advertise;
2606 		else
2607 			su = &pasv_addr;
2608 		ispassive = 1;
2609 		goto printaddr;
2610 	} else if (usedefault == 0) {
2611 		su = (struct sockinet *)&data_dest;
2612 
2613 		if (epsvall) {
2614 			reply(0, "EPSV only mode (EPSV ALL)");
2615 			goto epsvonly;
2616 		}
2617  printaddr:
2618 							/* PASV/PORT */
2619 		if (su->su_family == AF_INET) {
2620 			a = (unsigned char *) &su->su_addr;
2621 			p = (unsigned char *) &su->su_port;
2622 #define UC(b) (((int) b) & 0xff)
2623 			reply(0, "%s (%d,%d,%d,%d,%d,%d)",
2624 				ispassive ? "PASV" : "PORT" ,
2625 				UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
2626 				UC(p[0]), UC(p[1]));
2627 		}
2628 
2629 							/* LPSV/LPRT */
2630 	    {
2631 		int alen, i;
2632 
2633 		alen = 0;
2634 		switch (su->su_family) {
2635 		case AF_INET:
2636 			a = (unsigned char *) &su->su_addr;
2637 			p = (unsigned char *) &su->su_port;
2638 			alen = sizeof(su->su_addr);
2639 			af = 4;
2640 			break;
2641 #ifdef INET6
2642 		case AF_INET6:
2643 			a = (unsigned char *) &su->su_6addr;
2644 			p = (unsigned char *) &su->su_port;
2645 			alen = sizeof(su->su_6addr);
2646 			af = 6;
2647 			break;
2648 #endif
2649 		default:
2650 			af = 0;
2651 			break;
2652 		}
2653 		if (af) {
2654 			cprintf(stdout, "    %s (%d,%d",
2655 			    ispassive ? "LPSV" : "LPRT", af, alen);
2656 			for (i = 0; i < alen; i++)
2657 				cprintf(stdout, ",%d", UC(a[i]));
2658 			cprintf(stdout, ",%d,%d,%d)\r\n",
2659 			    2, UC(p[0]), UC(p[1]));
2660 #undef UC
2661 		}
2662 	    }
2663 
2664 		/* EPRT/EPSV */
2665  epsvonly:
2666 		af = af2epsvproto(su->su_family);
2667 		hbuf[0] = '\0';
2668 		if (af > 0) {
2669 			struct sockinet tmp;
2670 
2671 			tmp = *su;
2672 #ifdef INET6
2673 			if (tmp.su_family == AF_INET6)
2674 				tmp.su_scope_id = 0;
2675 #endif
2676 			if (getnameinfo((struct sockaddr *)&tmp.si_su,
2677 			    tmp.su_len, hbuf, sizeof(hbuf), sbuf, sizeof(sbuf),
2678 			    NI_NUMERICHOST | NI_NUMERICSERV) == 0)
2679 				reply(0, "%s (|%d|%s|%s|)",
2680 				    ispassive ? "EPSV" : "EPRT",
2681 				    af, hbuf, sbuf);
2682 		}
2683 	} else
2684 		reply(0, "No data connection");
2685 
2686 	if (logged_in) {
2687 		reply(0,
2688 		    "Data sent:        " LLF " byte%s in " LLF " file%s",
2689 		    (LLT)total_data_out, PLURAL(total_data_out),
2690 		    (LLT)total_files_out, PLURAL(total_files_out));
2691 		reply(0,
2692 		    "Data received:    " LLF " byte%s in " LLF " file%s",
2693 		    (LLT)total_data_in, PLURAL(total_data_in),
2694 		    (LLT)total_files_in, PLURAL(total_files_in));
2695 		reply(0,
2696 		    "Total data:       " LLF " byte%s in " LLF " file%s",
2697 		    (LLT)total_data, PLURAL(total_data),
2698 		    (LLT)total_files, PLURAL(total_files));
2699 	}
2700 	otbi = total_bytes_in;
2701 	otbo = total_bytes_out;
2702 	otb = total_bytes;
2703 	reply(0, "Traffic sent:     " LLF " byte%s in " LLF " transfer%s",
2704 	    (LLT)otbo, PLURAL(otbo),
2705 	    (LLT)total_xfers_out, PLURAL(total_xfers_out));
2706 	reply(0, "Traffic received: " LLF " byte%s in " LLF " transfer%s",
2707 	    (LLT)otbi, PLURAL(otbi),
2708 	    (LLT)total_xfers_in, PLURAL(total_xfers_in));
2709 	reply(0, "Total traffic:    " LLF " byte%s in " LLF " transfer%s",
2710 	    (LLT)otb, PLURAL(otb),
2711 	    (LLT)total_xfers, PLURAL(total_xfers));
2712 
2713 	if (logged_in && !CURCLASS_FLAGS_ISSET(private)) {
2714 		struct ftpconv *cp;
2715 
2716 		reply(0, "%s", "");
2717 		reply(0, "Class: %s, type: %s",
2718 		    curclass.classname, CURCLASSTYPE);
2719 		reply(0, "Check PORT/LPRT commands: %sabled",
2720 		    CURCLASS_FLAGS_ISSET(checkportcmd) ? "en" : "dis");
2721 		if (! EMPTYSTR(curclass.display))
2722 			reply(0, "Display file: %s", curclass.display);
2723 		if (! EMPTYSTR(curclass.notify))
2724 			reply(0, "Notify fileglob: %s", curclass.notify);
2725 		reply(0, "Idle timeout: " LLF ", maximum timeout: " LLF,
2726 		    (LLT)curclass.timeout, (LLT)curclass.maxtimeout);
2727 		reply(0, "Current connections: %d", connections);
2728 		if (curclass.limit == -1)
2729 			reply(0, "Maximum connections: unlimited");
2730 		else
2731 			reply(0, "Maximum connections: " LLF,
2732 			    (LLT)curclass.limit);
2733 		if (curclass.limitfile)
2734 			reply(0, "Connection limit exceeded message file: %s",
2735 			    conffilename(curclass.limitfile));
2736 		if (! EMPTYSTR(curclass.chroot))
2737 			reply(0, "Chroot format: %s", curclass.chroot);
2738 		reply(0, "Deny bad ftpusers(5) quickly: %sabled",
2739 		    CURCLASS_FLAGS_ISSET(denyquick) ? "en" : "dis");
2740 		if (! EMPTYSTR(curclass.homedir))
2741 			reply(0, "Homedir format: %s", curclass.homedir);
2742 		if (curclass.maxfilesize == -1)
2743 			reply(0, "Maximum file size: unlimited");
2744 		else
2745 			reply(0, "Maximum file size: " LLF,
2746 			    (LLT)curclass.maxfilesize);
2747 		if (! EMPTYSTR(curclass.motd))
2748 			reply(0, "MotD file: %s", conffilename(curclass.motd));
2749 		reply(0,
2750 	    "Modify commands (CHMOD, DELE, MKD, RMD, RNFR, UMASK): %sabled",
2751 		    CURCLASS_FLAGS_ISSET(modify) ? "en" : "dis");
2752 		reply(0, "Upload commands (APPE, STOR, STOU): %sabled",
2753 		    CURCLASS_FLAGS_ISSET(upload) ? "en" : "dis");
2754 		reply(0, "Sanitize file names: %sabled",
2755 		    CURCLASS_FLAGS_ISSET(sanenames) ? "en" : "dis");
2756 		reply(0, "PASV/LPSV/EPSV connections: %sabled",
2757 		    CURCLASS_FLAGS_ISSET(passive) ? "en" : "dis");
2758 		if (curclass.advertise.su_len != 0) {
2759 			char buf[50];	/* big enough for IPv6 address */
2760 			const char *bp;
2761 
2762 			bp = inet_ntop(curclass.advertise.su_family,
2763 			    (void *)&curclass.advertise.su_addr,
2764 			    buf, sizeof(buf));
2765 			if (bp != NULL)
2766 				reply(0, "PASV advertise address: %s", bp);
2767 		}
2768 		if (curclass.portmin && curclass.portmax)
2769 			reply(0, "PASV port range: " LLF " - " LLF,
2770 			    (LLT)curclass.portmin, (LLT)curclass.portmax);
2771 		if (curclass.rateget)
2772 			reply(0, "Rate get limit: " LLF " bytes/sec",
2773 			    (LLT)curclass.rateget);
2774 		else
2775 			reply(0, "Rate get limit: disabled");
2776 		if (curclass.rateput)
2777 			reply(0, "Rate put limit: " LLF " bytes/sec",
2778 			    (LLT)curclass.rateput);
2779 		else
2780 			reply(0, "Rate put limit: disabled");
2781 		if (curclass.mmapsize)
2782 			reply(0, "Mmap size: " LLF, (LLT)curclass.mmapsize);
2783 		else
2784 			reply(0, "Mmap size: disabled");
2785 		if (curclass.readsize)
2786 			reply(0, "Read size: " LLF, (LLT)curclass.readsize);
2787 		else
2788 			reply(0, "Read size: default");
2789 		if (curclass.writesize)
2790 			reply(0, "Write size: " LLF, (LLT)curclass.writesize);
2791 		else
2792 			reply(0, "Write size: default");
2793 		if (curclass.recvbufsize)
2794 			reply(0, "Receive buffer size: " LLF,
2795 			    (LLT)curclass.recvbufsize);
2796 		else
2797 			reply(0, "Receive buffer size: default");
2798 		if (curclass.sendbufsize)
2799 			reply(0, "Send buffer size: " LLF,
2800 			    (LLT)curclass.sendbufsize);
2801 		else
2802 			reply(0, "Send buffer size: default");
2803 		if (curclass.sendlowat)
2804 			reply(0, "Send low water mark: " LLF,
2805 			    (LLT)curclass.sendlowat);
2806 		else
2807 			reply(0, "Send low water mark: default");
2808 		reply(0, "Umask: %.04o", curclass.umask);
2809 		for (cp = curclass.conversions; cp != NULL; cp=cp->next) {
2810 			if (cp->suffix == NULL || cp->types == NULL ||
2811 			    cp->command == NULL)
2812 				continue;
2813 			reply(0, "Conversion: %s [%s] disable: %s, command: %s",
2814 			    cp->suffix, cp->types, cp->disable, cp->command);
2815 		}
2816 	}
2817 
2818 	reply(211, "End of status");
2819 }
2820 
2821 void
2822 fatal(const char *s)
2823 {
2824 
2825 	reply(451, "Error in server: %s\n", s);
2826 	reply(221, "Closing connection due to server error.");
2827 	dologout(0);
2828 	/* NOTREACHED */
2829 }
2830 
2831 /*
2832  * reply() --
2833  *	depending on the value of n, display fmt with a trailing CRLF and
2834  *	prefix of:
2835  *	n < -1		prefix the message with abs(n) + "-"	(initial line)
2836  *	n == 0		prefix the message with 4 spaces	(middle lines)
2837  *	n >  0		prefix the message with n + " "		(final line)
2838  */
2839 void
2840 reply(int n, const char *fmt, ...)
2841 {
2842 	char	msg[MAXPATHLEN * 2 + 100];
2843 	size_t	b;
2844 	va_list	ap;
2845 
2846 	if (n == 0)
2847 		b = snprintf(msg, sizeof(msg), "    ");
2848 	else if (n < 0)
2849 		b = snprintf(msg, sizeof(msg), "%d-", -n);
2850 	else
2851 		b = snprintf(msg, sizeof(msg), "%d ", n);
2852 	va_start(ap, fmt);
2853 	vsnprintf(msg + b, sizeof(msg) - b, fmt, ap);
2854 	va_end(ap);
2855 	cprintf(stdout, "%s\r\n", msg);
2856 	(void)fflush(stdout);
2857 	if (ftpd_debug)
2858 		syslog(LOG_DEBUG, "<--- %s", msg);
2859 }
2860 
2861 static void
2862 logremotehost(struct sockinet *who)
2863 {
2864 
2865 #if defined(HAVE_SOCKADDR_SNPRINTF)
2866 	char abuf[MAXHOSTNAMELEN];
2867 #endif
2868 
2869 	struct sockaddr *sa = (struct sockaddr *)&who->si_su;
2870 	if (getnameinfo(sa, who->su_len, remotehost, sizeof(remotehost), NULL,
2871 	    0, getnameopts))
2872 		strlcpy(remotehost, "?", sizeof(remotehost));
2873 #if defined(HAVE_SOCKADDR_SNPRINTF)
2874 	sockaddr_snprintf(abuf, sizeof(abuf), "%a", sa);
2875 	snprintf(remoteloghost, sizeof(remoteloghost), "%s(%s)", remotehost,
2876 	    abuf);
2877 #else
2878 	strlcpy(remoteloghost, remotehost, sizeof(remoteloghost));
2879 #endif
2880 
2881 #if defined(HAVE_SETPROCTITLE)
2882 	snprintf(proctitle, sizeof(proctitle), "%s: connected", remotehost);
2883 	setproctitle("%s", proctitle);
2884 #endif /* defined(HAVE_SETPROCTITLE) */
2885 	if (logging)
2886 		syslog(LOG_INFO, "connection from %s to %s",
2887 		    remoteloghost, hostname);
2888 }
2889 
2890 /*
2891  * Record logout in wtmp file and exit with supplied status.
2892  * NOTE: because this is called from signal handlers it cannot
2893  *       use stdio (or call other functions that use stdio).
2894  */
2895 void
2896 dologout(int status)
2897 {
2898 	/*
2899 	* Prevent reception of SIGURG from resulting in a resumption
2900 	* back to the main program loop.
2901 	*/
2902 	transflag = 0;
2903 	logout_utmp();
2904 	if (logged_in) {
2905 #ifdef KERBEROS
2906 		if (!notickets && krbtkfile_env)
2907 			unlink(krbtkfile_env);
2908 #endif
2909 	}
2910 	/* beware of flushing buffers after a SIGPIPE */
2911 	if (xferlogfd != -1)
2912 		close(xferlogfd);
2913 	_exit(status);
2914 }
2915 
2916 void
2917 abor(void)
2918 {
2919 
2920 	if (!transflag)
2921 		return;
2922 	tmpline[0] = '\0';
2923 	is_oob = 0;
2924 	reply(426, "Transfer aborted. Data connection closed.");
2925 	reply(226, "Abort successful");
2926 	transflag = 0;		/* flag that the transfer has aborted */
2927 }
2928 
2929 void
2930 statxfer(void)
2931 {
2932 
2933 	if (!transflag)
2934 		return;
2935 	tmpline[0] = '\0';
2936 	is_oob = 0;
2937 	if (file_size != (off_t) -1)
2938 		reply(213,
2939 		    "Status: " LLF " of " LLF " byte%s transferred",
2940 		    (LLT)byte_count, (LLT)file_size,
2941 		    PLURAL(byte_count));
2942 	else
2943 		reply(213, "Status: " LLF " byte%s transferred",
2944 		    (LLT)byte_count, PLURAL(byte_count));
2945 }
2946 
2947 /*
2948  * Call when urgflag != 0 to handle Out Of Band commands.
2949  * Returns non zero if the OOB command aborted the transfer
2950  * by setting transflag to 0. (c.f., "ABOR").
2951  */
2952 static int
2953 handleoobcmd(void)
2954 {
2955 	char *cp;
2956 	int ret;
2957 
2958 	if (!urgflag)
2959 		return (0);
2960 	urgflag = 0;
2961 	/* only process if transfer occurring */
2962 	if (!transflag)
2963 		return (0);
2964 	cp = tmpline;
2965 	ret = get_line(cp, sizeof(tmpline)-1, stdin);
2966 	if (ret == -1) {
2967 		reply(221, "You could at least say goodbye.");
2968 		dologout(0);
2969 	} else if (ret == -2) {
2970 		/* Ignore truncated command */
2971 		/* XXX: abort xfer with "500 command too long", & return 1 ? */
2972 		return 0;
2973 	}
2974 		/*
2975 		 * Manually parse OOB commands, because we can't
2976 		 * recursively call the yacc parser...
2977 		 */
2978 	if (strcasecmp(cp, "ABOR\r\n") == 0) {
2979 		abor();
2980 	} else if (strcasecmp(cp, "STAT\r\n") == 0) {
2981 		statxfer();
2982 	} else {
2983 		/* XXX: error with "500 unknown command" ? */
2984 	}
2985 	return (transflag == 0);
2986 }
2987 
2988 static int
2989 bind_pasv_addr(void)
2990 {
2991 	static int passiveport;
2992 	int port, len;
2993 
2994 	len = pasv_addr.su_len;
2995 	if (curclass.portmin == 0 && curclass.portmax == 0) {
2996 		pasv_addr.su_port = 0;
2997 		return (bind(pdata, (struct sockaddr *)&pasv_addr.si_su, len));
2998 	}
2999 
3000 	if (passiveport == 0) {
3001 		srand(getpid());
3002 		passiveport = rand() % (curclass.portmax - curclass.portmin)
3003 		    + curclass.portmin;
3004 	}
3005 
3006 	port = passiveport;
3007 	while (1) {
3008 		port++;
3009 		if (port > curclass.portmax)
3010 			port = curclass.portmin;
3011 		else if (port == passiveport) {
3012 			errno = EAGAIN;
3013 			return (-1);
3014 		}
3015 		pasv_addr.su_port = htons(port);
3016 		if (bind(pdata, (struct sockaddr *)&pasv_addr.si_su, len) == 0)
3017 			break;
3018 		if (errno != EADDRINUSE)
3019 			return (-1);
3020 	}
3021 	passiveport = port;
3022 	return (0);
3023 }
3024 
3025 /*
3026  * Note: a response of 425 is not mentioned as a possible response to
3027  *	the PASV command in RFC959. However, it has been blessed as
3028  *	a legitimate response by Jon Postel in a telephone conversation
3029  *	with Rick Adams on 25 Jan 89.
3030  */
3031 void
3032 passive(void)
3033 {
3034 	socklen_t len;
3035 	int recvbufsize;
3036 	char *p, *a;
3037 
3038 	if (pdata >= 0)
3039 		close(pdata);
3040 	pdata = socket(AF_INET, SOCK_STREAM, 0);
3041 	if (pdata < 0 || !logged_in) {
3042 		perror_reply(425, "Can't open passive connection");
3043 		return;
3044 	}
3045 	pasv_addr = ctrl_addr;
3046 
3047 	if (bind_pasv_addr() < 0)
3048 		goto pasv_error;
3049 	len = pasv_addr.su_len;
3050 	if (getsockname(pdata, (struct sockaddr *) &pasv_addr.si_su, &len) < 0)
3051 		goto pasv_error;
3052 	pasv_addr.su_len = len;
3053 	if (curclass.recvbufsize) {
3054 		recvbufsize = curclass.recvbufsize;
3055 		if (setsockopt(pdata, SOL_SOCKET, SO_RCVBUF, &recvbufsize,
3056 			       sizeof(int)) == -1)
3057 			syslog(LOG_WARNING, "setsockopt(SO_RCVBUF, %d): %m",
3058 			       recvbufsize);
3059 	}
3060 	if (listen(pdata, 1) < 0)
3061 		goto pasv_error;
3062 	if (curclass.advertise.su_len != 0)
3063 		a = (char *) &curclass.advertise.su_addr;
3064 	else
3065 		a = (char *) &pasv_addr.su_addr;
3066 	p = (char *) &pasv_addr.su_port;
3067 
3068 #define UC(b) (((int) b) & 0xff)
3069 
3070 	reply(227, "Entering Passive Mode (%d,%d,%d,%d,%d,%d)", UC(a[0]),
3071 		UC(a[1]), UC(a[2]), UC(a[3]), UC(p[0]), UC(p[1]));
3072 	return;
3073 
3074  pasv_error:
3075 	(void) close(pdata);
3076 	pdata = -1;
3077 	perror_reply(425, "Can't open passive connection");
3078 	return;
3079 }
3080 
3081 /*
3082  * convert protocol identifier to/from AF
3083  */
3084 int
3085 lpsvproto2af(int proto)
3086 {
3087 
3088 	switch (proto) {
3089 	case 4:
3090 		return AF_INET;
3091 #ifdef INET6
3092 	case 6:
3093 		return AF_INET6;
3094 #endif
3095 	default:
3096 		return -1;
3097 	}
3098 }
3099 
3100 int
3101 af2lpsvproto(int af)
3102 {
3103 
3104 	switch (af) {
3105 	case AF_INET:
3106 		return 4;
3107 #ifdef INET6
3108 	case AF_INET6:
3109 		return 6;
3110 #endif
3111 	default:
3112 		return -1;
3113 	}
3114 }
3115 
3116 int
3117 epsvproto2af(int proto)
3118 {
3119 
3120 	switch (proto) {
3121 	case 1:
3122 		return AF_INET;
3123 #ifdef INET6
3124 	case 2:
3125 		return AF_INET6;
3126 #endif
3127 	default:
3128 		return -1;
3129 	}
3130 }
3131 
3132 int
3133 af2epsvproto(int af)
3134 {
3135 
3136 	switch (af) {
3137 	case AF_INET:
3138 		return 1;
3139 #ifdef INET6
3140 	case AF_INET6:
3141 		return 2;
3142 #endif
3143 	default:
3144 		return -1;
3145 	}
3146 }
3147 
3148 /*
3149  * 228 Entering Long Passive Mode (af, hal, h1, h2, h3,..., pal, p1, p2...)
3150  * 229 Entering Extended Passive Mode (|||port|)
3151  */
3152 void
3153 long_passive(const char *cmd, int pf)
3154 {
3155 	socklen_t len;
3156 	char *p, *a;
3157 
3158 	if (!logged_in) {
3159 		syslog(LOG_NOTICE, "long passive but not logged in");
3160 		reply(503, "Login with USER first.");
3161 		return;
3162 	}
3163 
3164 	if (pf != PF_UNSPEC && ctrl_addr.su_family != pf) {
3165 		/*
3166 		 * XXX: only EPRT/EPSV ready clients will understand this
3167 		 */
3168 		if (strcmp(cmd, "EPSV") != 0)
3169 			reply(501, "Network protocol mismatch"); /*XXX*/
3170 		else
3171 			epsv_protounsupp("Network protocol mismatch");
3172 
3173 		return;
3174 	}
3175 
3176 	if (pdata >= 0)
3177 		close(pdata);
3178 	pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
3179 	if (pdata < 0) {
3180 		perror_reply(425, "Can't open passive connection");
3181 		return;
3182 	}
3183 	pasv_addr = ctrl_addr;
3184 	if (bind_pasv_addr() < 0)
3185 		goto pasv_error;
3186 	len = pasv_addr.su_len;
3187 	if (getsockname(pdata, (struct sockaddr *) &pasv_addr.si_su, &len) < 0)
3188 		goto pasv_error;
3189 	pasv_addr.su_len = len;
3190 	if (listen(pdata, 1) < 0)
3191 		goto pasv_error;
3192 	p = (char *) &pasv_addr.su_port;
3193 
3194 #define UC(b) (((int) b) & 0xff)
3195 
3196 	if (strcmp(cmd, "LPSV") == 0) {
3197 		struct sockinet *advert;
3198 
3199 		if (curclass.advertise.su_len != 0)
3200 			advert = &curclass.advertise;
3201 		else
3202 			advert = &pasv_addr;
3203 		switch (advert->su_family) {
3204 		case AF_INET:
3205 			a = (char *) &advert->su_addr;
3206 			reply(228,
3207     "Entering Long Passive Mode (%d,%d,%d,%d,%d,%d,%d,%d,%d)",
3208 				4, 4, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
3209 				2, UC(p[0]), UC(p[1]));
3210 			return;
3211 #ifdef INET6
3212 		case AF_INET6:
3213 			a = (char *) &advert->su_6addr;
3214 			reply(228,
3215     "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)",
3216 				6, 16,
3217 				UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
3218 				UC(a[4]), UC(a[5]), UC(a[6]), UC(a[7]),
3219 				UC(a[8]), UC(a[9]), UC(a[10]), UC(a[11]),
3220 				UC(a[12]), UC(a[13]), UC(a[14]), UC(a[15]),
3221 				2, UC(p[0]), UC(p[1]));
3222 			return;
3223 #endif
3224 		}
3225 #undef UC
3226 	} else if (strcmp(cmd, "EPSV") == 0) {
3227 		switch (pasv_addr.su_family) {
3228 		case AF_INET:
3229 #ifdef INET6
3230 		case AF_INET6:
3231 #endif
3232 			reply(229, "Entering Extended Passive Mode (|||%d|)",
3233 			    ntohs(pasv_addr.su_port));
3234 			return;
3235 		}
3236 	} else {
3237 		/* more proper error code? */
3238 	}
3239 
3240  pasv_error:
3241 	(void) close(pdata);
3242 	pdata = -1;
3243 	perror_reply(425, "Can't open passive connection");
3244 	return;
3245 }
3246 
3247 int
3248 extended_port(const char *arg)
3249 {
3250 	char *tmp = NULL;
3251 	char *result[3];
3252 	char *p, *q;
3253 	char delim;
3254 	struct addrinfo hints;
3255 	struct addrinfo *res = NULL;
3256 	int i;
3257 	unsigned long proto;
3258 
3259 	tmp = ftpd_strdup(arg);
3260 	p = tmp;
3261 	delim = p[0];
3262 	p++;
3263 	memset(result, 0, sizeof(result));
3264 	for (i = 0; i < 3; i++) {
3265 		q = strchr(p, delim);
3266 		if (!q || *q != delim)
3267 			goto parsefail;
3268 		*q++ = '\0';
3269 		result[i] = p;
3270 		p = q;
3271 	}
3272 
3273 			/* some more sanity checks */
3274 	errno = 0;
3275 	p = NULL;
3276 	(void)strtoul(result[2], &p, 10);
3277 	if (errno || !*result[2] || *p)
3278 		goto parsefail;
3279 	errno = 0;
3280 	p = NULL;
3281 	proto = strtoul(result[0], &p, 10);
3282 	if (errno || !*result[0] || *p)
3283 		goto protounsupp;
3284 
3285 	memset(&hints, 0, sizeof(hints));
3286 	hints.ai_family = epsvproto2af((int)proto);
3287 	if (hints.ai_family < 0)
3288 		goto protounsupp;
3289 	hints.ai_socktype = SOCK_STREAM;
3290 	hints.ai_flags = AI_NUMERICHOST;
3291 	if (getaddrinfo(result[1], result[2], &hints, &res))
3292 		goto parsefail;
3293 	if (res->ai_next)
3294 		goto parsefail;
3295 	if (sizeof(data_dest) < res->ai_addrlen)
3296 		goto parsefail;
3297 	memcpy(&data_dest.si_su, res->ai_addr, res->ai_addrlen);
3298 	data_dest.su_len = res->ai_addrlen;
3299 #ifdef INET6
3300 	if (his_addr.su_family == AF_INET6 &&
3301 	    data_dest.su_family == AF_INET6) {
3302 			/* XXX: more sanity checks! */
3303 		data_dest.su_scope_id = his_addr.su_scope_id;
3304 	}
3305 #endif
3306 
3307 	if (tmp != NULL)
3308 		free(tmp);
3309 	if (res)
3310 		freeaddrinfo(res);
3311 	return 0;
3312 
3313  parsefail:
3314 	reply(500, "Invalid argument, rejected.");
3315 	usedefault = 1;
3316 	if (tmp != NULL)
3317 		free(tmp);
3318 	if (res)
3319 		freeaddrinfo(res);
3320 	return -1;
3321 
3322  protounsupp:
3323 	epsv_protounsupp("Protocol not supported");
3324 	usedefault = 1;
3325 	if (tmp != NULL)
3326 		free(tmp);
3327 	return -1;
3328 }
3329 
3330 /*
3331  * 522 Protocol not supported (proto,...)
3332  * as we assume address family for control and data connections are the same,
3333  * we do not return the list of address families we support - instead, we
3334  * return the address family of the control connection.
3335  */
3336 void
3337 epsv_protounsupp(const char *message)
3338 {
3339 	int proto;
3340 
3341 	proto = af2epsvproto(ctrl_addr.su_family);
3342 	if (proto < 0)
3343 		reply(501, "%s", message);	/* XXX */
3344 	else
3345 		reply(522, "%s, use (%d)", message, proto);
3346 }
3347 
3348 /*
3349  * Generate unique name for file with basename "local".
3350  * The file named "local" is already known to exist.
3351  * Generates failure reply on error.
3352  *
3353  * XXX:	this function should under go changes similar to
3354  *	the mktemp(3)/mkstemp(3) changes.
3355  */
3356 static char *
3357 gunique(const char *local)
3358 {
3359 	static char new[MAXPATHLEN];
3360 	struct stat st;
3361 	char *cp;
3362 	int count;
3363 
3364 	cp = strrchr(local, '/');
3365 	if (cp)
3366 		*cp = '\0';
3367 	if (stat(cp ? local : ".", &st) < 0) {
3368 		perror_reply(553, cp ? local : ".");
3369 		return (NULL);
3370 	}
3371 	if (cp)
3372 		*cp = '/';
3373 	for (count = 1; count < 100; count++) {
3374 		(void)snprintf(new, sizeof(new) - 1, "%s.%d", local, count);
3375 		if (stat(new, &st) < 0)
3376 			return (new);
3377 	}
3378 	reply(452, "Unique file name cannot be created.");
3379 	return (NULL);
3380 }
3381 
3382 /*
3383  * Format and send reply containing system error number.
3384  */
3385 void
3386 perror_reply(int code, const char *string)
3387 {
3388 	int save_errno;
3389 
3390 	save_errno = errno;
3391 	reply(code, "%s: %s.", string, strerror(errno));
3392 	errno = save_errno;
3393 }
3394 
3395 static char *onefile[] = {
3396 	NULL,
3397 	0
3398 };
3399 
3400 void
3401 send_file_list(const char *whichf)
3402 {
3403 	struct stat st;
3404 	DIR *dirp;
3405 	struct dirent *dir;
3406 	FILE *volatile dout;
3407 	char **volatile dirlist;
3408 	char *dirname, *p;
3409 	char *notglob;
3410 	int volatile simple;
3411 	int volatile freeglob;
3412 	glob_t gl;
3413 
3414 	dirp = NULL;
3415 	dout = NULL;
3416 	notglob = NULL;
3417 	simple = 0;
3418 	freeglob = 0;
3419 	urgflag = 0;
3420 
3421 	p = NULL;
3422 	if (strpbrk(whichf, "~{[*?") != NULL) {
3423 		int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE|GLOB_LIMIT;
3424 
3425 		memset(&gl, 0, sizeof(gl));
3426 		freeglob = 1;
3427 		if (glob(whichf, flags, 0, &gl)) {
3428 			reply(450, "Not found");
3429 			goto cleanup_send_file_list;
3430 		} else if (gl.gl_pathc == 0) {
3431 			errno = ENOENT;
3432 			perror_reply(450, whichf);
3433 			goto cleanup_send_file_list;
3434 		}
3435 		dirlist = gl.gl_pathv;
3436 	} else {
3437 		notglob = ftpd_strdup(whichf);
3438 		onefile[0] = notglob;
3439 		dirlist = onefile;
3440 		simple = 1;
3441 	}
3442 					/* XXX: } for vi sm */
3443 
3444 	while ((dirname = *dirlist++) != NULL) {
3445 		int trailingslash = 0;
3446 
3447 		if (stat(dirname, &st) < 0) {
3448 			/*
3449 			 * If user typed "ls -l", etc, and the client
3450 			 * used NLST, do what the user meant.
3451 			 */
3452 			/* XXX: nuke this support? */
3453 			if (dirname[0] == '-' && *dirlist == NULL &&
3454 			    transflag == 0) {
3455 				const char *argv[] = { INTERNAL_LS, "", NULL };
3456 
3457 				argv[1] = dirname;
3458 				retrieve(argv, dirname);
3459 				goto cleanup_send_file_list;
3460 			}
3461 			perror_reply(450, whichf);
3462 			goto cleanup_send_file_list;
3463 		}
3464 
3465 		if (S_ISREG(st.st_mode)) {
3466 			/*
3467 			 * XXXRFC:
3468 			 *	should we follow RFC959 and not work
3469 			 *	for non directories?
3470 			 */
3471 			if (dout == NULL) {
3472 				dout = dataconn("file list", (off_t)-1, "w");
3473 				if (dout == NULL)
3474 					goto cleanup_send_file_list;
3475 				transflag = 1;
3476 			}
3477 			cprintf(dout, "%s%s\n", dirname,
3478 			    type == TYPE_A ? "\r" : "");
3479 			continue;
3480 		} else if (!S_ISDIR(st.st_mode))
3481 			continue;
3482 
3483 		if (dirname[strlen(dirname) - 1] == '/')
3484 			trailingslash++;
3485 
3486 		if ((dirp = opendir(dirname)) == NULL)
3487 			continue;
3488 
3489 		while ((dir = readdir(dirp)) != NULL) {
3490 			char nbuf[MAXPATHLEN];
3491 
3492 			if (urgflag && handleoobcmd()) {
3493 				(void) closedir(dirp);
3494 				goto cleanup_send_file_list;
3495 			}
3496 
3497 			if (ISDOTDIR(dir->d_name) || ISDOTDOTDIR(dir->d_name))
3498 				continue;
3499 
3500 			(void)snprintf(nbuf, sizeof(nbuf), "%s%s%s", dirname,
3501 			    trailingslash ? "" : "/", dir->d_name);
3502 
3503 			/*
3504 			 * We have to do a stat to ensure it's
3505 			 * not a directory or special file.
3506 			 */
3507 			/*
3508 			 * XXXRFC:
3509 			 *	should we follow RFC959 and filter out
3510 			 *	non files ?   lukem - NO!, or not until
3511 			 *	our ftp client uses MLS{T,D} for completion.
3512 			 */
3513 			if (simple || (stat(nbuf, &st) == 0 &&
3514 			    S_ISREG(st.st_mode))) {
3515 				if (dout == NULL) {
3516 					dout = dataconn("file list", (off_t)-1,
3517 						"w");
3518 					if (dout == NULL) {
3519 						(void) closedir(dirp);
3520 						goto cleanup_send_file_list;
3521 					}
3522 					transflag = 1;
3523 				}
3524 				p = nbuf;
3525 				if (nbuf[0] == '.' && nbuf[1] == '/')
3526 					p = &nbuf[2];
3527 				cprintf(dout, "%s%s\n", p,
3528 				    type == TYPE_A ? "\r" : "");
3529 			}
3530 		}
3531 		(void) closedir(dirp);
3532 	}
3533 
3534 	if (dout == NULL)
3535 		reply(450, "No files found.");
3536 	else if (ferror(dout) != 0)
3537 		perror_reply(451, "Data connection");
3538 	else
3539 		reply(226, "Transfer complete.");
3540 
3541  cleanup_send_file_list:
3542 	closedataconn(dout);
3543 	transflag = 0;
3544 	urgflag = 0;
3545 	total_xfers++;
3546 	total_xfers_out++;
3547 	if (notglob)
3548 		free(notglob);
3549 	if (freeglob)
3550 		globfree(&gl);
3551 }
3552 
3553 char *
3554 conffilename(const char *s)
3555 {
3556 	static char filename[MAXPATHLEN];
3557 
3558 	if (*s == '/')
3559 		strlcpy(filename, s, sizeof(filename));
3560 	else
3561 		(void)snprintf(filename, sizeof(filename), "%s/%s", confdir ,s);
3562 	return (filename);
3563 }
3564 
3565 /*
3566  * logxfer --
3567  *	if logging > 1, then based on the arguments, syslog a message:
3568  *	 if bytes != -1		"<command> <file1> = <bytes> bytes"
3569  *	 else if file2 != NULL	"<command> <file1> <file2>"
3570  *	 else			"<command> <file1>"
3571  *	if elapsed != NULL, append "in xxx.yyy seconds"
3572  *	if error != NULL, append ": " + error
3573  *
3574  *	if doxferlog != 0, bytes != -1, and command is "get", "put",
3575  *	or "append", syslog and/or write a wu-ftpd style xferlog entry
3576  */
3577 void
3578 logxfer(const char *command, off_t bytes, const char *file1, const char *file2,
3579     const struct timeval *elapsed, const char *error)
3580 {
3581 	char		 buf[MAXPATHLEN * 2 + 100];
3582 	char		 realfile1[MAXPATHLEN], realfile2[MAXPATHLEN];
3583 	const char	*r1, *r2;
3584 	char		 direction;
3585 	size_t		 len;
3586 	time_t		 now;
3587 
3588 	if (logging <=1 && !doxferlog)
3589 		return;
3590 
3591 	r1 = r2 = NULL;
3592 	if ((r1 = realpath(file1, realfile1)) == NULL)
3593 		r1 = file1;
3594 	if (file2 != NULL)
3595 		if ((r2 = realpath(file2, realfile2)) == NULL)
3596 			r2 = file2;
3597 
3598 		/*
3599 		 * syslog command
3600 		 */
3601 	if (logging > 1) {
3602 		len = snprintf(buf, sizeof(buf), "%s %s", command, r1);
3603 		if (bytes != (off_t)-1)
3604 			len += snprintf(buf + len, sizeof(buf) - len,
3605 			    " = " LLF " byte%s", (LLT) bytes, PLURAL(bytes));
3606 		else if (r2 != NULL)
3607 			len += snprintf(buf + len, sizeof(buf) - len,
3608 			    " %s", r2);
3609 		if (elapsed != NULL)
3610 			len += snprintf(buf + len, sizeof(buf) - len,
3611 			    " in " LLF ".%.03ld seconds",
3612 			    (LLT)elapsed->tv_sec,
3613 			    (long)(elapsed->tv_usec / 1000));
3614 		if (error != NULL)
3615 			len += snprintf(buf + len, sizeof(buf) - len,
3616 			    ": %s", error);
3617 		syslog(LOG_INFO, "%s", buf);
3618 	}
3619 
3620 		/*
3621 		 * syslog wu-ftpd style log entry, prefixed with "xferlog: "
3622 		 */
3623 	if (!doxferlog || bytes == -1)
3624 		return;
3625 
3626 	if (strcmp(command, "get") == 0)
3627 		direction = 'o';
3628 	else if (strcmp(command, "put") == 0 || strcmp(command, "append") == 0)
3629 		direction = 'i';
3630 	else
3631 		return;
3632 
3633 	time(&now);
3634 	len = snprintf(buf, sizeof(buf),
3635 	    "%.24s " LLF " %s " LLF " %s %c %s %c %c %s FTP 0 * %c\n",
3636 
3637 /*
3638  * XXX: wu-ftpd puts ' (send)' or ' (recv)' in the syslog message, and removes
3639  *	the full date.  This may be problematic for accurate log parsing,
3640  *	given that syslog messages don't contain the full date.
3641  */
3642 	    ctime(&now),
3643 	    (LLT)
3644 	    (elapsed == NULL ? 0 : elapsed->tv_sec + (elapsed->tv_usec > 0)),
3645 	    remotehost,
3646 	    (LLT) bytes,
3647 	    r1,
3648 	    type == TYPE_A ? 'a' : 'b',
3649 	    "_",		/* XXX: take conversions into account? */
3650 	    direction,
3651 
3652 	    curclass.type == CLASS_GUEST ?  'a' :
3653 	    curclass.type == CLASS_CHROOT ? 'g' :
3654 	    curclass.type == CLASS_REAL ?   'r' : '?',
3655 
3656 	    curclass.type == CLASS_GUEST ? pw->pw_passwd : pw->pw_name,
3657 	    error != NULL ? 'i' : 'c'
3658 	    );
3659 
3660 	if ((doxferlog & 2) && xferlogfd != -1)
3661 		write(xferlogfd, buf, len);
3662 	if ((doxferlog & 1)) {
3663 		buf[len-1] = '\n';	/* strip \n from syslog message */
3664 		syslog(LOG_INFO, "xferlog: %s", buf);
3665 	}
3666 }
3667 
3668 /*
3669  * Log the resource usage.
3670  *
3671  * XXX: more resource usage to logging?
3672  */
3673 void
3674 logrusage(const struct rusage *rusage_before,
3675     const struct rusage *rusage_after)
3676 {
3677 	struct timeval usrtime, systime;
3678 
3679 	if (logging <= 1)
3680 		return;
3681 
3682 	timersub(&rusage_after->ru_utime, &rusage_before->ru_utime, &usrtime);
3683 	timersub(&rusage_after->ru_stime, &rusage_before->ru_stime, &systime);
3684 	syslog(LOG_INFO, LLF ".%.03ldu " LLF ".%.03lds %ld+%ldio %ldpf+%ldw",
3685 	    (LLT)usrtime.tv_sec, (long)(usrtime.tv_usec / 1000),
3686 	    (LLT)systime.tv_sec, (long)(systime.tv_usec / 1000),
3687 	    rusage_after->ru_inblock - rusage_before->ru_inblock,
3688 	    rusage_after->ru_oublock - rusage_before->ru_oublock,
3689 	    rusage_after->ru_majflt - rusage_before->ru_majflt,
3690 	    rusage_after->ru_nswap - rusage_before->ru_nswap);
3691 }
3692 
3693 /*
3694  * Determine if `password' is valid for user given in `pw'.
3695  * Returns 2 if password expired, 1 if otherwise failed, 0 if ok
3696  */
3697 int
3698 checkpassword(const struct passwd *pwent, const char *password)
3699 {
3700 	const char *orig;
3701 	char	*new;
3702 	time_t	 change, expire, now;
3703 
3704 	change = expire = 0;
3705 	if (pwent == NULL)
3706 		return 1;
3707 
3708 	time(&now);
3709 	orig = pwent->pw_passwd;	/* save existing password */
3710 	expire = pwent->pw_expire;
3711 	change = pwent->pw_change;
3712 	if (change == _PASSWORD_CHGNOW)
3713 		change = now;
3714 
3715 	if (orig[0] == '\0')		/* don't allow empty passwords */
3716 		return 1;
3717 
3718 	new = crypt(password, orig);	/* encrypt given password */
3719 	if (strcmp(new, orig) != 0)	/* compare */
3720 		return 1;
3721 
3722 	if ((expire && now >= expire) || (change && now >= change))
3723 		return 2;		/* check if expired */
3724 
3725 	return 0;			/* OK! */
3726 }
3727 
3728 char *
3729 ftpd_strdup(const char *s)
3730 {
3731 	char *new = strdup(s);
3732 
3733 	if (new == NULL)
3734 		fatal("Local resource failure: malloc");
3735 		/* NOTREACHED */
3736 	return (new);
3737 }
3738 
3739 /*
3740  * As per fprintf(), but increment total_bytes and total_bytes_out,
3741  * by the appropriate amount.
3742  */
3743 void
3744 cprintf(FILE *fd, const char *fmt, ...)
3745 {
3746 	off_t b;
3747 	va_list ap;
3748 
3749 	va_start(ap, fmt);
3750 	b = vfprintf(fd, fmt, ap);
3751 	va_end(ap);
3752 	total_bytes += b;
3753 	total_bytes_out += b;
3754 }
3755 
3756 #ifdef USE_PAM
3757 /*
3758  * the following code is stolen from imap-uw PAM authentication module and
3759  * login.c
3760  */
3761 typedef struct {
3762 	const char *uname;	/* user name */
3763 	int	    triedonce;	/* if non-zero, tried before */
3764 } ftpd_cred_t;
3765 
3766 static int
3767 auth_conv(int num_msg, const struct pam_message **msg,
3768     struct pam_response **resp, void *appdata)
3769 {
3770 	int i, ret;
3771 	size_t n;
3772 	ftpd_cred_t *cred = (ftpd_cred_t *) appdata;
3773 	struct pam_response *myreply;
3774 	char pbuf[FTP_BUFLEN];
3775 
3776 	if (num_msg <= 0 || num_msg > PAM_MAX_NUM_MSG)
3777 		return (PAM_CONV_ERR);
3778 	myreply = calloc(num_msg, sizeof *myreply);
3779 	if (myreply == NULL)
3780 		return PAM_BUF_ERR;
3781 
3782 	for (i = 0; i < num_msg; i++) {
3783 		myreply[i].resp_retcode = 0;
3784 		myreply[i].resp = NULL;
3785 		switch (msg[i]->msg_style) {
3786 		case PAM_PROMPT_ECHO_ON:	/* user */
3787 			myreply[i].resp = ftpd_strdup(cred->uname);
3788 			/* PAM frees resp. */
3789 			break;
3790 		case PAM_PROMPT_ECHO_OFF:	/* authtok (password) */
3791 				/*
3792 				 * Only send a single 331 reply and
3793 				 * then expect a PASS.
3794 				 */
3795 			if (cred->triedonce) {
3796 				syslog(LOG_ERR,
3797 			"auth_conv: already performed PAM_PROMPT_ECHO_OFF");
3798 				goto fail;
3799 			}
3800 			cred->triedonce++;
3801 			if (msg[i]->msg[0] == '\0') {
3802 				(void)strlcpy(pbuf, "password", sizeof(pbuf));
3803 			} else {
3804 					/* Uncapitalize msg */
3805 				(void)strlcpy(pbuf, msg[i]->msg, sizeof(pbuf));
3806 				if (isupper((unsigned char)pbuf[0]))
3807 					pbuf[0] = tolower(
3808 					    (unsigned char)pbuf[0]);
3809 					/* Remove trailing ':' and whitespace */
3810 				n = strlen(pbuf);
3811 				while (n-- > 0) {
3812 					if (isspace((unsigned char)pbuf[n]) ||
3813 					    pbuf[n] == ':')
3814 						pbuf[n] = '\0';
3815 					else
3816 						break;
3817 				}
3818 			}
3819 				/* Send reply, wait for a response. */
3820 			reply(331, "User %s accepted, provide %s.",
3821 			    cred->uname, pbuf);
3822 			(void) alarm(curclass.timeout);
3823 			ret = get_line(pbuf, sizeof(pbuf)-1, stdin);
3824 			(void) alarm(0);
3825 			if (ret == -1) {
3826 				reply(221, "You could at least say goodbye.");
3827 				dologout(0);
3828 			} else if (ret == -2) {
3829 			    /* XXX: should we do this reply(-530, ..) ? */
3830 				reply(-530, "Command too long.");
3831 				goto fail;
3832 			}
3833 				/* Ensure it is PASS */
3834 			if (strncasecmp(pbuf, "PASS ", 5) != 0) {
3835 				syslog(LOG_ERR,
3836 				    "auth_conv: unexpected reply '%.4s'", pbuf);
3837 				/* XXX: should we do this reply(-530, ..) ? */
3838 				reply(-530, "Unexpected reply '%.4s'.", pbuf);
3839 				goto fail;
3840 			}
3841 				/* Strip CRLF from "PASS" reply */
3842 			n = strlen(pbuf);
3843 			while (--n >= 5 &&
3844 			    (pbuf[n] == '\r' || pbuf[n] == '\n'))
3845 			    pbuf[n] = '\0';
3846 				/* Copy password into reply */
3847 			myreply[i].resp = ftpd_strdup(pbuf+5);
3848 				/* PAM frees resp. */
3849 			break;
3850 		case PAM_TEXT_INFO:
3851 		case PAM_ERROR_MSG:
3852 			break;
3853 		default:			/* unknown message style */
3854 			goto fail;
3855 		}
3856 	}
3857 
3858 	*resp = myreply;
3859 	return PAM_SUCCESS;
3860 
3861  fail:
3862 	free(myreply);
3863 	*resp = NULL;
3864 	return PAM_CONV_ERR;
3865 }
3866 
3867 /*
3868  * Attempt to authenticate the user using PAM.  Returns 0 if the user is
3869  * authenticated, or 1 if not authenticated.  If some sort of PAM system
3870  * error occurs (e.g., the "/etc/pam.conf" file is missing) then this
3871  * function returns -1.  This can be used as an indication that we should
3872  * fall back to a different authentication mechanism.
3873  * pw maybe be updated to a new user if PAM_USER changes from curname.
3874  */
3875 static int
3876 auth_pam(void)
3877 {
3878 	const char *tmpl_user;
3879 	const void *item;
3880 	int rval;
3881 	int e;
3882 	ftpd_cred_t auth_cred = { curname, 0 };
3883 	struct pam_conv conv = { &auth_conv, &auth_cred };
3884 
3885 	e = pam_start("ftpd", curname, &conv, &pamh);
3886 	if (e != PAM_SUCCESS) {
3887 		/*
3888 		 * In OpenPAM, it's OK to pass NULL to pam_strerror()
3889 		 * if context creation has failed in the first place.
3890 		 */
3891 		syslog(LOG_ERR, "pam_start: %s", pam_strerror(NULL, e));
3892 		return -1;
3893 	}
3894 
3895 	e = pam_set_item(pamh, PAM_RHOST, remotehost);
3896 	if (e != PAM_SUCCESS) {
3897 		syslog(LOG_ERR, "pam_set_item(PAM_RHOST): %s",
3898 			pam_strerror(pamh, e));
3899 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
3900 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
3901 		}
3902 		pamh = NULL;
3903 		return -1;
3904 	}
3905 
3906 	e = pam_set_item(pamh, PAM_SOCKADDR, &his_addr);
3907 	if (e != PAM_SUCCESS) {
3908 		syslog(LOG_ERR, "pam_set_item(PAM_SOCKADDR): %s",
3909 			pam_strerror(pamh, e));
3910 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
3911 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
3912 		}
3913 		pamh = NULL;
3914 		return -1;
3915 	}
3916 
3917 	e = pam_authenticate(pamh, 0);
3918 	if (ftpd_debug)
3919 		syslog(LOG_DEBUG, "pam_authenticate: user '%s' returned %d",
3920 		    curname, e);
3921 	switch (e) {
3922 	case PAM_SUCCESS:
3923 		/*
3924 		 * With PAM we support the concept of a "template"
3925 		 * user.  The user enters a login name which is
3926 		 * authenticated by PAM, usually via a remote service
3927 		 * such as RADIUS or TACACS+.  If authentication
3928 		 * succeeds, a different but related "template" name
3929 		 * is used for setting the credentials, shell, and
3930 		 * home directory.  The name the user enters need only
3931 		 * exist on the remote authentication server, but the
3932 		 * template name must be present in the local password
3933 		 * database.
3934 		 *
3935 		 * This is supported by two various mechanisms in the
3936 		 * individual modules.  However, from the application's
3937 		 * point of view, the template user is always passed
3938 		 * back as a changed value of the PAM_USER item.
3939 		 */
3940 		if ((e = pam_get_item(pamh, PAM_USER, &item)) ==
3941 		    PAM_SUCCESS) {
3942 			tmpl_user = (const char *) item;
3943 			if (pw == NULL
3944 			    || strcmp(pw->pw_name, tmpl_user) != 0) {
3945 				pw = sgetpwnam(tmpl_user);
3946 				if (ftpd_debug)
3947 					syslog(LOG_DEBUG,
3948 					    "auth_pam: PAM changed "
3949 					    "user from '%s' to '%s'",
3950 					    curname, pw->pw_name);
3951 				(void)strlcpy(curname, pw->pw_name,
3952 				    curname_len);
3953 			}
3954 		} else
3955 			syslog(LOG_ERR, "Couldn't get PAM_USER: %s",
3956 			    pam_strerror(pamh, e));
3957 		rval = 0;
3958 		break;
3959 
3960 	case PAM_AUTH_ERR:
3961 	case PAM_USER_UNKNOWN:
3962 	case PAM_MAXTRIES:
3963 		rval = 1;
3964 		break;
3965 
3966 	default:
3967 		syslog(LOG_ERR, "pam_authenticate: %s", pam_strerror(pamh, e));
3968 		rval = -1;
3969 		break;
3970 	}
3971 
3972 	if (rval == 0) {
3973 		e = pam_acct_mgmt(pamh, 0);
3974 		if (e != PAM_SUCCESS) {
3975 			syslog(LOG_ERR, "pam_acct_mgmt: %s",
3976 						pam_strerror(pamh, e));
3977 			rval = 1;
3978 		}
3979 	}
3980 
3981 	if (rval != 0) {
3982 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
3983 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
3984 		}
3985 		pamh = NULL;
3986 	}
3987 	return rval;
3988 }
3989 
3990 #endif /* USE_PAM */
3991