xref: /minix3/libexec/ftpd/ftpd.c (revision b5e2faaaaf60a8b9a02f8d72f64caa56a87eb312)
1 /*	$NetBSD: ftpd.c,v 1.200 2013/07/31 19:50:47 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 1.200 2013/07/31 19:50:47 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 #define	GLOBAL
169 #include "extern.h"
170 #include "pathnames.h"
171 #include "version.h"
172 
173 static sig_atomic_t	transflag;
174 static sig_atomic_t	urgflag;
175 
176 int	data;
177 int	Dflag;
178 int	sflag;
179 int	stru;			/* avoid C keyword */
180 int	mode;
181 int	dataport;		/* use specific data port */
182 int	dopidfile;		/* maintain pid file */
183 int	doutmp;			/* update utmp file */
184 int	dowtmp;			/* update wtmp file */
185 int	doxferlog;		/* syslog/write wu-ftpd style xferlog entries */
186 int	xferlogfd;		/* fd to write wu-ftpd xferlog entries to */
187 int	getnameopts;		/* flags for use with getname() */
188 int	dropprivs;		/* if privileges should or have been dropped */
189 int	mapped;			/* IPv4 connection on AF_INET6 socket */
190 off_t	file_size;
191 off_t	byte_count;
192 static char ttyline[20];
193 
194 #ifdef USE_PAM
195 static int	auth_pam(void);
196 pam_handle_t	*pamh = NULL;
197 #endif
198 
199 #ifdef SUPPORT_UTMP
200 static struct utmp utmp;	/* for utmp */
201 #endif
202 #ifdef SUPPORT_UTMPX
203 static struct utmpx utmpx;	/* for utmpx */
204 #endif
205 
206 static const char *anondir = NULL;
207 static const char *confdir = _DEFAULT_CONFDIR;
208 
209 static char	*curname;		/* current USER name */
210 static size_t	curname_len;		/* length of curname (include NUL) */
211 
212 #if defined(KERBEROS) || defined(KERBEROS5)
213 int	has_ccache = 0;
214 int	notickets = 1;
215 char	*krbtkfile_env = NULL;
216 char	*tty = ttyline;
217 int	login_krb5_forwardable_tgt = 0;
218 #endif
219 
220 int epsvall = 0;
221 
222 /*
223  * Timeout intervals for retrying connections
224  * to hosts that don't accept PORT cmds.  This
225  * is a kludge, but given the problems with TCP...
226  */
227 #define	SWAITMAX	90	/* wait at most 90 seconds */
228 #define	SWAITINT	5	/* interval between retries */
229 
230 int	swaitmax = SWAITMAX;
231 int	swaitint = SWAITINT;
232 
233 enum send_status {
234 	SS_SUCCESS,
235 	SS_ABORTED,			/* transfer aborted */
236 	SS_NO_TRANSFER,			/* no transfer made yet */
237 	SS_FILE_ERROR,			/* file read error */
238 	SS_DATA_ERROR			/* data send error */
239 };
240 
241 static int	 bind_pasv_addr(void);
242 static int	 checkuser(const char *, const char *, int, int, char **);
243 static int	 checkaccess(const char *);
244 static int	 checkpassword(const struct passwd *, const char *);
245 static void	 do_pass(int, int, const char *);
246 static void	 end_login(void);
247 static FILE	*getdatasock(const char *);
248 static char	*gunique(const char *);
249 static void	 login_utmp(const char *, const char *, const char *,
250 		     struct sockinet *);
251 static void	 logremotehost(struct sockinet *);
252 __dead static void	 lostconn(int);
253 __dead static void	 toolong(int);
254 __dead static void	 sigquit(int);
255 static void	 sigurg(int);
256 static int	 handleoobcmd(void);
257 static int	 receive_data(FILE *, FILE *);
258 static int	 send_data(FILE *, FILE *, const struct stat *, int);
259 static struct passwd *sgetpwnam(const char *);
260 static int	 write_data(int, char *, size_t, off_t *, struct timeval *,
261 		     int);
262 static enum send_status
263 		 send_data_with_read(int, int, const struct stat *, int);
264 #if !defined(__minix)
265 static enum send_status
266 		 send_data_with_mmap(int, int, const struct stat *, int);
267 static void	 logrusage(const struct rusage *, const struct rusage *);
268 #endif /* !defined(__minix) */
269 static void	 logout_utmp(void);
270 
271 int	main(int, char *[]);
272 
273 #if defined(KERBEROS)
274 int	klogin(struct passwd *, char *, char *, char *);
275 void	kdestroy(void);
276 #endif
277 #if defined(KERBEROS5)
278 int	k5login(struct passwd *, char *, char *, char *);
279 void	k5destroy(void);
280 #endif
281 
282 int
283 main(int argc, char *argv[])
284 {
285 	int		ch, on = 1, tos, keepalive;
286 	socklen_t	addrlen;
287 #ifdef KERBEROS5
288 	krb5_error_code	kerror;
289 #endif
290 	char		*p;
291 	const char	*xferlogname = NULL;
292 	long		l;
293 	struct sigaction sa;
294 	sa_family_t	af = AF_UNSPEC;
295 
296 	connections = 1;
297 	ftpd_debug = 0;
298 	logging = 0;
299 	pdata = -1;
300 	Dflag = 0;
301 	sflag = 0;
302 	dataport = 0;
303 	dopidfile = 1;		/* default: DO use a pid file to count users */
304 	doutmp = 0;		/* default: Do NOT log to utmp */
305 	dowtmp = 1;		/* default: DO log to wtmp */
306 	doxferlog = 0;		/* default: Do NOT syslog xferlog */
307 	xferlogfd = -1;		/* default: Do NOT write xferlog file */
308 	getnameopts = 0;	/* default: xlate addrs to name */
309 	dropprivs = 0;
310 	mapped = 0;
311 	usedefault = 1;
312 	emailaddr = NULL;
313 	hostname[0] = '\0';
314 	homedir[0] = '\0';
315 	gidcount = 0;
316 	is_oob = 0;
317 	version = FTPD_VERSION;
318 
319 	/*
320 	 * LOG_NDELAY sets up the logging connection immediately,
321 	 * necessary for anonymous ftp's that chroot and can't do it later.
322 	 */
323 	openlog("ftpd", LOG_PID | LOG_NDELAY, LOG_FTP);
324 
325 	while ((ch = getopt(argc, argv,
326 	    "46a:c:C:Dde:h:HlL:nP:qQrst:T:uUvV:wWX")) != -1) {
327 		switch (ch) {
328 		case '4':
329 			af = AF_INET;
330 			break;
331 
332 		case '6':
333 			af = AF_INET6;
334 			break;
335 
336 		case 'a':
337 			anondir = optarg;
338 			break;
339 
340 		case 'c':
341 			confdir = optarg;
342 			break;
343 
344 		case 'C':
345 			if ((p = strchr(optarg, '@')) != NULL) {
346 				*p++ = '\0';
347 				strlcpy(remotehost, p, MAXHOSTNAMELEN + 1);
348 				if (inet_pton(AF_INET, p,
349 				    &his_addr.su_addr) == 1) {
350 					his_addr.su_family = AF_INET;
351 					his_addr.su_len =
352 					    sizeof(his_addr.si_su.su_sin);
353 #ifdef INET6
354 				} else if (inet_pton(AF_INET6, p,
355 				    &his_addr.su_6addr) == 1) {
356 					his_addr.su_family = AF_INET6;
357 					his_addr.su_len =
358 					    sizeof(his_addr.si_su.su_sin6);
359 #endif
360 				} else
361 					his_addr.su_family = AF_UNSPEC;
362 			}
363 			pw = sgetpwnam(optarg);
364 			exit(checkaccess(optarg) ? 0 : 1);
365 			/* NOTREACHED */
366 
367 		case 'D':
368 			Dflag = 1;
369 			break;
370 
371 		case 'd':
372 		case 'v':		/* deprecated */
373 			ftpd_debug = 1;
374 			break;
375 
376 		case 'e':
377 			emailaddr = optarg;
378 			break;
379 
380 		case 'h':
381 			strlcpy(hostname, optarg, sizeof(hostname));
382 			break;
383 
384 		case 'H':
385 			if (gethostname(hostname, sizeof(hostname)) == -1)
386 				hostname[0] = '\0';
387 			hostname[sizeof(hostname) - 1] = '\0';
388 			break;
389 
390 		case 'l':
391 			logging++;	/* > 1 == extra logging */
392 			break;
393 
394 		case 'L':
395 			xferlogname = optarg;
396 			break;
397 
398 		case 'n':
399 			getnameopts = NI_NUMERICHOST;
400 			break;
401 
402 		case 'P':
403 			errno = 0;
404 			p = NULL;
405 			l = strtol(optarg, &p, 10);
406 			if (errno || *optarg == '\0' || *p != '\0' ||
407 			    l < IPPORT_RESERVED ||
408 			    l > IPPORT_ANONMAX) {
409 				syslog(LOG_WARNING, "Invalid dataport %s",
410 				    optarg);
411 				dataport = 0;
412 			}
413 			dataport = (int)l;
414 			break;
415 
416 		case 'q':
417 			dopidfile = 1;
418 			break;
419 
420 		case 'Q':
421 			dopidfile = 0;
422 			break;
423 
424 		case 'r':
425 			dropprivs = 1;
426 			break;
427 
428 		case 's':
429 			sflag = 1;
430 			break;
431 
432 		case 't':
433 		case 'T':
434 			syslog(LOG_WARNING,
435 			    "-%c has been deprecated in favour of ftpd.conf",
436 			    ch);
437 			break;
438 
439 		case 'u':
440 			doutmp = 1;
441 			break;
442 
443 		case 'U':
444 			doutmp = 0;
445 			break;
446 
447 		case 'V':
448 			if (EMPTYSTR(optarg) || strcmp(optarg, "-") == 0)
449 				version = NULL;
450 			else
451 				version = ftpd_strdup(optarg);
452 			break;
453 
454 		case 'w':
455 			dowtmp = 1;
456 			break;
457 
458 		case 'W':
459 			dowtmp = 0;
460 			break;
461 
462 		case 'X':
463 			doxferlog |= 1;
464 			break;
465 
466 		default:
467 			if (optopt == 'a' || optopt == 'C')
468 				exit(1);
469 			syslog(LOG_WARNING, "unknown flag -%c ignored", optopt);
470 			break;
471 		}
472 	}
473 	if (EMPTYSTR(confdir))
474 		confdir = _DEFAULT_CONFDIR;
475 
476 	if (dowtmp) {
477 #ifdef SUPPORT_UTMPX
478 		ftpd_initwtmpx();
479 #endif
480 #ifdef SUPPORT_UTMP
481 		ftpd_initwtmp();
482 #endif
483 	}
484 	errno = 0;
485 #if !defined(__minix)
486 	l = sysconf(_SC_LOGIN_NAME_MAX);
487 	if (l == -1 && errno != 0) {
488 		syslog(LOG_ERR, "sysconf _SC_LOGIN_NAME_MAX: %m");
489 		exit(1);
490 	} else if (l <= 0) {
491 		syslog(LOG_WARNING, "using conservative LOGIN_NAME_MAX value");
492 		curname_len = _POSIX_LOGIN_NAME_MAX;
493 	} else
494 		curname_len = (size_t)l;
495 #else
496 	curname_len = _POSIX_LOGIN_NAME_MAX;
497 #endif /* !defined(__minix) */
498 	curname = malloc(curname_len);
499 	if (curname == NULL) {
500 		syslog(LOG_ERR, "malloc: %m");
501 		exit(1);
502 	}
503 	curname[0] = '\0';
504 
505 	if (Dflag) {
506 		int error, fd, i, n, *socks;
507 		struct pollfd *fds;
508 		struct addrinfo hints, *res, *res0;
509 
510 		if (daemon(1, 0) == -1) {
511 			syslog(LOG_ERR, "failed to daemonize: %m");
512 			exit(1);
513 		}
514 		(void)memset(&sa, 0, sizeof(sa));
515 		sa.sa_handler = SIG_IGN;
516 		sa.sa_flags = SA_NOCLDWAIT;
517 		sigemptyset(&sa.sa_mask);
518 		(void)sigaction(SIGCHLD, &sa, NULL);
519 
520 		(void)memset(&hints, 0, sizeof(hints));
521 		hints.ai_flags = AI_PASSIVE;
522 		hints.ai_family = af;
523 		hints.ai_socktype = SOCK_STREAM;
524 		error = getaddrinfo(NULL, "ftp", &hints, &res0);
525 		if (error) {
526 			syslog(LOG_ERR, "getaddrinfo: %s", gai_strerror(error));
527 			exit(1);
528 		}
529 
530 		for (n = 0, res = res0; res != NULL; res = res->ai_next)
531 			n++;
532 		if (n == 0) {
533 			syslog(LOG_ERR, "no addresses available");
534 			exit(1);
535 		}
536 		socks = malloc(n * sizeof(int));
537 		fds = malloc(n * sizeof(struct pollfd));
538 		if (socks == NULL || fds == NULL) {
539 			syslog(LOG_ERR, "malloc: %m");
540 			exit(1);
541 		}
542 
543 		for (n = 0, res = res0; res != NULL; res = res->ai_next) {
544 			socks[n] = socket(res->ai_family, res->ai_socktype,
545 			    res->ai_protocol);
546 			if (socks[n] == -1)
547 				continue;
548 			(void)setsockopt(socks[n], SOL_SOCKET, SO_REUSEADDR,
549 			    &on, sizeof(on));
550 			if (bind(socks[n], res->ai_addr, res->ai_addrlen)
551 			    == -1) {
552 				(void)close(socks[n]);
553 				continue;
554 			}
555 			if (listen(socks[n], 12) == -1) {
556 				(void)close(socks[n]);
557 				continue;
558 			}
559 
560 			fds[n].fd = socks[n];
561 			fds[n].events = POLLIN;
562 			n++;
563 		}
564 		if (n == 0) {
565 			syslog(LOG_ERR, "%m");
566 			exit(1);
567 		}
568 		freeaddrinfo(res0);
569 
570 		if (pidfile(NULL) == -1)
571 			syslog(LOG_ERR, "failed to write a pid file: %m");
572 
573 		for (;;) {
574 			if (poll(fds, n, INFTIM) == -1) {
575 				if (errno == EINTR)
576 					continue;
577 				syslog(LOG_ERR, "poll: %m");
578 				exit(1);
579 			}
580 			for (i = 0; i < n; i++) {
581 				if (fds[i].revents & POLLIN) {
582 					fd = accept(fds[i].fd, NULL, NULL);
583 					if (fd == -1) {
584 						syslog(LOG_ERR, "accept: %m");
585 						continue;
586 					}
587 					switch (fork()) {
588 					case -1:
589 						syslog(LOG_ERR, "fork: %m");
590 						break;
591 					case 0:
592 						goto child;
593 						/* NOTREACHED */
594 					}
595 					(void)close(fd);
596 				}
597 			}
598 		}
599  child:
600 		(void)dup2(fd, STDIN_FILENO);
601 		(void)dup2(fd, STDOUT_FILENO);
602 		(void)dup2(fd, STDERR_FILENO);
603 		for (i = 0; i < n; i++)
604 			(void)close(socks[i]);
605 	}
606 
607 	memset((char *)&his_addr, 0, sizeof(his_addr));
608 	addrlen = sizeof(his_addr.si_su);
609 	if (getpeername(0, (struct sockaddr *)&his_addr.si_su, &addrlen) < 0) {
610 		syslog((errno == ENOTCONN) ? LOG_NOTICE : LOG_ERR,
611 		    "getpeername (%s): %m",argv[0]);
612 		exit(1);
613 	}
614 	his_addr.su_len = addrlen;
615 	memset((char *)&ctrl_addr, 0, sizeof(ctrl_addr));
616 	addrlen = sizeof(ctrl_addr.si_su);
617 	if (getsockname(0, (struct sockaddr *)&ctrl_addr, &addrlen) < 0) {
618 		syslog(LOG_ERR, "getsockname (%s): %m",argv[0]);
619 		exit(1);
620 	}
621 	ctrl_addr.su_len = addrlen;
622 #ifdef INET6
623 	if (his_addr.su_family == AF_INET6
624 	 && IN6_IS_ADDR_V4MAPPED(&his_addr.su_6addr)) {
625 #if 1
626 		/*
627 		 * IPv4 control connection arrived to AF_INET6 socket.
628 		 * I hate to do this, but this is the easiest solution.
629 		 *
630 		 * The assumption is untrue on SIIT environment.
631 		 */
632 		struct sockinet tmp_addr;
633 		const int off = sizeof(struct in6_addr) - sizeof(struct in_addr);
634 
635 		tmp_addr = his_addr;
636 		memset(&his_addr, 0, sizeof(his_addr));
637 		his_addr.su_family = AF_INET;
638 		his_addr.su_len = sizeof(his_addr.si_su.su_sin);
639 		memcpy(&his_addr.su_addr, &tmp_addr.su_6addr.s6_addr[off],
640 		    sizeof(his_addr.su_addr));
641 		his_addr.su_port = tmp_addr.su_port;
642 
643 		tmp_addr = ctrl_addr;
644 		memset(&ctrl_addr, 0, sizeof(ctrl_addr));
645 		ctrl_addr.su_family = AF_INET;
646 		ctrl_addr.su_len = sizeof(ctrl_addr.si_su.su_sin);
647 		memcpy(&ctrl_addr.su_addr, &tmp_addr.su_6addr.s6_addr[off],
648 		    sizeof(ctrl_addr.su_addr));
649 		ctrl_addr.su_port = tmp_addr.su_port;
650 #else
651 		while (fgets(line, sizeof(line), fd) != NULL) {
652 			if ((cp = strchr(line, '\n')) != NULL)
653 				*cp = '\0';
654 			reply(-530, "%s", line);
655 		}
656 		(void) fflush(stdout);
657 		(void) fclose(fd);
658 		reply(530,
659 		    "Connection from IPv4 mapped address is not supported.");
660 		exit(0);
661 #endif
662 
663 		mapped = 1;
664 	} else
665 #endif /* INET6 */
666 		mapped = 0;
667 #ifdef IP_TOS
668 	if (!mapped && his_addr.su_family == AF_INET) {
669 		tos = IPTOS_LOWDELAY;
670 		if (setsockopt(0, IPPROTO_IP, IP_TOS, (char *)&tos,
671 			       sizeof(int)) < 0)
672 			syslog(LOG_WARNING, "setsockopt (IP_TOS): %m");
673 	}
674 #endif
675 	/* if the hostname hasn't been given, attempt to determine it */
676 	if (hostname[0] == '\0') {
677 		if (getnameinfo((struct sockaddr *)&ctrl_addr.si_su,
678 		    ctrl_addr.su_len, hostname, sizeof(hostname), NULL, 0,
679 			getnameopts) != 0)
680 			(void)gethostname(hostname, sizeof(hostname));
681 		hostname[sizeof(hostname) - 1] = '\0';
682 	}
683 
684 	/* set this here so klogin can use it... */
685 	(void)snprintf(ttyline, sizeof(ttyline), "ftp%d", getpid());
686 
687 	(void) freopen(_PATH_DEVNULL, "w", stderr);
688 
689 	memset(&sa, 0, sizeof(sa));
690 	sa.sa_handler = SIG_DFL;
691 	sa.sa_flags = SA_RESTART;
692 	sigemptyset(&sa.sa_mask);
693 	(void) sigaction(SIGCHLD, &sa, NULL);
694 
695 	sa.sa_handler = sigquit;
696 	sa.sa_flags = SA_RESTART;
697 	sigfillset(&sa.sa_mask);	/* block all sigs in these handlers */
698 	(void) sigaction(SIGHUP, &sa, NULL);
699 	(void) sigaction(SIGINT, &sa, NULL);
700 	(void) sigaction(SIGQUIT, &sa, NULL);
701 	(void) sigaction(SIGTERM, &sa, NULL);
702 	sa.sa_handler = lostconn;
703 	(void) sigaction(SIGPIPE, &sa, NULL);
704 	sa.sa_handler = toolong;
705 	(void) sigaction(SIGALRM, &sa, NULL);
706 	sa.sa_handler = sigurg;
707 #if !defined(__minix)
708 	(void) sigaction(SIGURG, &sa, NULL);
709 
710 	/* Try to handle urgent data inline */
711 #ifdef SO_OOBINLINE
712 	if (setsockopt(0, SOL_SOCKET, SO_OOBINLINE, (char *)&on, sizeof(on)) < 0)
713 		syslog(LOG_WARNING, "setsockopt: %m");
714 #endif
715 	/* Set keepalives on the socket to detect dropped connections.  */
716 #ifdef SO_KEEPALIVE
717 	keepalive = 1;
718 	if (setsockopt(0, SOL_SOCKET, SO_KEEPALIVE, (char *)&keepalive,
719 	    sizeof(int)) < 0)
720 		syslog(LOG_WARNING, "setsockopt (SO_KEEPALIVE): %m");
721 #endif
722 #endif /* !defined(__minix) */
723 
724 #ifdef	F_SETOWN
725 	if (fcntl(fileno(stdin), F_SETOWN, getpid()) == -1)
726 		syslog(LOG_WARNING, "fcntl F_SETOWN: %m");
727 #endif
728 	logremotehost(&his_addr);
729 	/*
730 	 * Set up default state
731 	 */
732 	data = -1;
733 	type = TYPE_A;
734 	form = FORM_N;
735 	stru = STRU_F;
736 	mode = MODE_S;
737 	tmpline[0] = '\0';
738 	hasyyerrored = 0;
739 
740 #ifdef KERBEROS5
741 	kerror = krb5_init_context(&kcontext);
742 	if (kerror) {
743 		syslog(LOG_ERR, "%s when initializing Kerberos context",
744 		    error_message(kerror));
745 		exit(0);
746 	}
747 #endif /* KERBEROS5 */
748 
749 	init_curclass();
750 	curclass.timeout = 300;		/* 5 minutes, as per login(1) */
751 	curclass.type = CLASS_REAL;
752 
753 	/* If logins are disabled, print out the message. */
754 	if (display_file(_PATH_NOLOGIN, 530)) {
755 		reply(530, "System not available.");
756 		exit(0);
757 	}
758 	(void)display_file(conffilename(_NAME_FTPWELCOME), 220);
759 		/* reply(220,) must follow */
760 	if (EMPTYSTR(version))
761 		reply(220, "%s FTP server ready.", hostname);
762 	else
763 		reply(220, "%s FTP server (%s) ready.", hostname, version);
764 
765 	if (xferlogname != NULL) {
766 		xferlogfd = open(xferlogname, O_WRONLY | O_APPEND | O_CREAT,
767 		    0660);
768 		if (xferlogfd == -1)
769 			syslog(LOG_WARNING, "open xferlog `%s': %m",
770 			    xferlogname);
771 		else
772 			doxferlog |= 2;
773 	}
774 
775 	ftp_loop();
776 	/* NOTREACHED */
777 }
778 
779 static void
780 lostconn(int signo __unused)
781 {
782 
783 	if (ftpd_debug)
784 		syslog(LOG_DEBUG, "lost connection");
785 	dologout(1);
786 }
787 
788 static void
789 toolong(int signo __unused)
790 {
791 
792 		/* XXXSIGRACE */
793 	reply(421,
794 	    "Timeout (" LLF " seconds): closing control connection.",
795 	    (LLT)curclass.timeout);
796 	if (logging)
797 		syslog(LOG_INFO, "User %s timed out after " LLF " seconds",
798 		    (pw ? pw->pw_name : "unknown"), (LLT)curclass.timeout);
799 	dologout(1);
800 }
801 
802 static void
803 sigquit(int signo)
804 {
805 
806 	if (ftpd_debug)
807 		syslog(LOG_DEBUG, "got signal %d", signo);
808 	dologout(1);
809 }
810 
811 static void
812 sigurg(int signo __unused)
813 {
814 
815 	urgflag = 1;
816 }
817 
818 
819 /*
820  * Save the result of a getpwnam.  Used for USER command, since
821  * the data returned must not be clobbered by any other command
822  * (e.g., globbing).
823  */
824 static struct passwd *
825 sgetpwnam(const char *name)
826 {
827 	static struct passwd save;
828 	struct passwd *p;
829 
830 	if ((p = getpwnam(name)) == NULL)
831 		return (p);
832 	if (save.pw_name) {
833 		free((char *)save.pw_name);
834 		memset(save.pw_passwd, 0, strlen(save.pw_passwd));
835 		free((char *)save.pw_passwd);
836 		free((char *)save.pw_gecos);
837 		free((char *)save.pw_dir);
838 		free((char *)save.pw_shell);
839 	}
840 	save = *p;
841 	save.pw_name = ftpd_strdup(p->pw_name);
842 	save.pw_passwd = ftpd_strdup(p->pw_passwd);
843 	save.pw_gecos = ftpd_strdup(p->pw_gecos);
844 	save.pw_dir = ftpd_strdup(p->pw_dir);
845 	save.pw_shell = ftpd_strdup(p->pw_shell);
846 	return (&save);
847 }
848 
849 static int	login_attempts;	/* number of failed login attempts */
850 static int	askpasswd;	/* had USER command, ask for PASSwd */
851 static int	permitted;	/* USER permitted */
852 
853 /*
854  * USER command.
855  * Sets global passwd pointer pw if named account exists and is acceptable;
856  * sets askpasswd if a PASS command is expected.  If logged in previously,
857  * need to reset state.  If name is "ftp" or "anonymous", the name is not in
858  * _NAME_FTPUSERS, and ftp account exists, set guest and pw, then just return.
859  * If account doesn't exist, ask for passwd anyway.  Otherwise, check user
860  * requesting login privileges.  Disallow anyone who does not have a standard
861  * shell as returned by getusershell().  Disallow anyone mentioned in the file
862  * _NAME_FTPUSERS to allow people such as root and uucp to be avoided.
863  */
864 void
865 user(const char *name)
866 {
867 	char	*class;
868 #ifdef	LOGIN_CAP
869 	login_cap_t *lc = NULL;
870 #endif
871 #ifdef USE_PAM
872 	int e;
873 #endif
874 
875 	class = NULL;
876 	if (logged_in) {
877 		switch (curclass.type) {
878 		case CLASS_GUEST:
879 			reply(530, "Can't change user from guest login.");
880 			return;
881 		case CLASS_CHROOT:
882 			reply(530, "Can't change user from chroot user.");
883 			return;
884 		case CLASS_REAL:
885 			if (dropprivs) {
886 				reply(530, "Can't change user.");
887 				return;
888 			}
889 			end_login();
890 			break;
891 		default:
892 			abort();
893 		}
894 	}
895 
896 #if defined(KERBEROS)
897 	kdestroy();
898 #endif
899 #if defined(KERBEROS5)
900 	k5destroy();
901 #endif
902 
903 	curclass.type = CLASS_REAL;
904 	askpasswd = 0;
905 	permitted = 0;
906 
907 	if (strcmp(name, "ftp") == 0 || strcmp(name, "anonymous") == 0) {
908 			/* need `pw' setup for checkaccess() and checkuser () */
909 		if ((pw = sgetpwnam("ftp")) == NULL)
910 			reply(530, "User %s unknown.", name);
911 		else if (! checkaccess("ftp") || ! checkaccess("anonymous"))
912 			reply(530, "User %s access denied.", name);
913 		else {
914 			curclass.type = CLASS_GUEST;
915 			askpasswd = 1;
916 			reply(331,
917 			    "Guest login ok, type your name as password.");
918 		}
919 		if (!askpasswd) {
920 			if (logging)
921 				syslog(LOG_NOTICE,
922 				    "ANONYMOUS FTP LOGIN REFUSED FROM %s",
923 				    remoteloghost);
924 			end_login();
925 			goto cleanup_user;
926 		}
927 		name = "ftp";
928 	} else
929 		pw = sgetpwnam(name);
930 
931 	strlcpy(curname, name, curname_len);
932 
933 			/* check user in /etc/ftpusers, and setup class */
934 	permitted = checkuser(_NAME_FTPUSERS, curname, 1, 0, &class);
935 
936 			/* check user in /etc/ftpchroot */
937 #ifdef	LOGIN_CAP
938 	lc = login_getpwclass(pw);
939 #endif
940 	if (checkuser(_NAME_FTPCHROOT, curname, 0, 0, NULL)
941 #ifdef	LOGIN_CAP	/* Allow login.conf configuration as well */
942 	    || login_getcapbool(lc, "ftp-chroot", 0)
943 #endif
944 	) {
945 		if (curclass.type == CLASS_GUEST) {
946 			syslog(LOG_NOTICE,
947 	    "Can't change guest user to chroot class; remove entry in %s",
948 			    _NAME_FTPCHROOT);
949 			exit(1);
950 		}
951 		curclass.type = CLASS_CHROOT;
952 	}
953 
954 			/* determine default class */
955 	if (class == NULL) {
956 		switch (curclass.type) {
957 		case CLASS_GUEST:
958 			class = ftpd_strdup("guest");
959 			break;
960 		case CLASS_CHROOT:
961 			class = ftpd_strdup("chroot");
962 			break;
963 		case CLASS_REAL:
964 			class = ftpd_strdup("real");
965 			break;
966 		default:
967 			syslog(LOG_ERR, "unknown curclass.type %d; aborting",
968 			    curclass.type);
969 			abort();
970 		}
971 	}
972 			/* parse ftpd.conf, setting up various parameters */
973 	parse_conf(class);
974 			/* if not guest user, check for valid shell */
975 	if (pw == NULL)
976 		permitted = 0;
977 	else {
978 		const char	*cp, *shell;
979 
980 		if ((shell = pw->pw_shell) == NULL || *shell == 0)
981 			shell = _PATH_BSHELL;
982 		while ((cp = getusershell()) != NULL)
983 			if (strcmp(cp, shell) == 0)
984 				break;
985 		endusershell();
986 		if (cp == NULL && curclass.type != CLASS_GUEST)
987 			permitted = 0;
988 	}
989 
990 			/* deny quickly (after USER not PASS) if requested */
991 	if (CURCLASS_FLAGS_ISSET(denyquick) && !permitted) {
992 		reply(530, "User %s may not use FTP.", curname);
993 		if (logging)
994 			syslog(LOG_NOTICE, "FTP LOGIN REFUSED FROM %s, %s",
995 			    remoteloghost, curname);
996 		end_login();
997 		goto cleanup_user;
998 	}
999 
1000 			/* if haven't asked yet (i.e, not anon), ask now */
1001 	if (!askpasswd) {
1002 		askpasswd = 1;
1003 #ifdef USE_PAM
1004 		e = auth_pam();		/* this does reply(331, ...) */
1005 		do_pass(1, e, "");
1006 		goto cleanup_user;
1007 #else /* !USE_PAM */
1008 #ifdef SKEY
1009 		if (skey_haskey(curname) == 0) {
1010 			const char *myskey;
1011 
1012 			myskey = skey_keyinfo(curname);
1013 			reply(331, "Password [ %s ] required for %s.",
1014 			    myskey ? myskey : "error getting challenge",
1015 			    curname);
1016 		} else
1017 #endif
1018 			reply(331, "Password required for %s.", curname);
1019 #endif /* !USE_PAM */
1020 	}
1021 
1022  cleanup_user:
1023 #ifdef LOGIN_CAP
1024 	login_close(lc);
1025 #endif
1026 	/*
1027 	 * Delay before reading passwd after first failed
1028 	 * attempt to slow down passwd-guessing programs.
1029 	 */
1030 	if (login_attempts)
1031 		sleep((unsigned) login_attempts);
1032 
1033 	if (class)
1034 		free(class);
1035 }
1036 
1037 /*
1038  * Determine whether something is to happen (allow access, chroot)
1039  * for a user. Each line is a shell-style glob followed by
1040  * `yes' or `no'.
1041  *
1042  * For backward compatibility, `allow' and `deny' are synonymns
1043  * for `yes' and `no', respectively.
1044  *
1045  * Each glob is matched against the username in turn, and the first
1046  * match found is used. If no match is found, the result is the
1047  * argument `def'. If a match is found but without and explicit
1048  * `yes'/`no', the result is the opposite of def.
1049  *
1050  * If the file doesn't exist at all, the result is the argument
1051  * `nofile'
1052  *
1053  * Any line starting with `#' is considered a comment and ignored.
1054  *
1055  * Returns 0 if the user is denied, or 1 if they are allowed.
1056  *
1057  * NOTE: needs struct passwd *pw setup before use.
1058  */
1059 static int
1060 checkuser(const char *fname, const char *name, int def, int nofile,
1061 	    char **retclass)
1062 {
1063 	FILE	*fd;
1064 	int	 retval;
1065 	char	*word, *perm, *class, *buf, *p;
1066 	size_t	 len, line;
1067 
1068 	retval = def;
1069 	if (retclass != NULL)
1070 		*retclass = NULL;
1071 	if ((fd = fopen(conffilename(fname), "r")) == NULL)
1072 		return nofile;
1073 
1074 	line = 0;
1075 	for (;
1076 	    (buf = fparseln(fd, &len, &line, NULL, FPARSELN_UNESCCOMM |
1077 			    FPARSELN_UNESCCONT | FPARSELN_UNESCESC)) != NULL;
1078 	    free(buf), buf = NULL) {
1079 		word = perm = class = NULL;
1080 		p = buf;
1081 		if (len < 1)
1082 			continue;
1083 		if (p[len - 1] == '\n')
1084 			p[--len] = '\0';
1085 		if (EMPTYSTR(p))
1086 			continue;
1087 
1088 		NEXTWORD(p, word);
1089 		NEXTWORD(p, perm);
1090 		NEXTWORD(p, class);
1091 		if (EMPTYSTR(word))
1092 			continue;
1093 		if (!EMPTYSTR(class)) {
1094 			if (strcasecmp(class, "all") == 0 ||
1095 			    strcasecmp(class, "none") == 0) {
1096 				syslog(LOG_WARNING,
1097 		"%s line %d: illegal user-defined class `%s' - skipping entry",
1098 					    fname, (int)line, class);
1099 				continue;
1100 			}
1101 		}
1102 
1103 					/* have a host specifier */
1104 		if ((p = strchr(word, '@')) != NULL) {
1105 			unsigned char	net[16], mask[16], *addr;
1106 			int		addrlen, bits, bytes, a;
1107 
1108 			*p++ = '\0';
1109 					/* check against network or CIDR */
1110 			memset(net, 0x00, sizeof(net));
1111 			if ((bits = inet_net_pton(his_addr.su_family, p, net,
1112 			    sizeof(net))) != -1) {
1113 #ifdef INET6
1114 				if (his_addr.su_family == AF_INET) {
1115 #endif
1116 					addrlen = 4;
1117 					addr = (unsigned char *)&his_addr.su_addr;
1118 #ifdef INET6
1119 				} else {
1120 					addrlen = 16;
1121 					addr = (unsigned char *)&his_addr.su_6addr;
1122 				}
1123 #endif
1124 				bytes = bits / 8;
1125 				bits = bits % 8;
1126 				if (bytes > 0)
1127 					memset(mask, 0xFF, bytes);
1128 				if (bytes < addrlen)
1129 					mask[bytes] = 0xFF << (8 - bits);
1130 				if (bytes + 1 < addrlen)
1131 					memset(mask + bytes + 1, 0x00,
1132 					    addrlen - bytes - 1);
1133 				for (a = 0; a < addrlen; a++)
1134 					if ((addr[a] & mask[a]) != net[a])
1135 						break;
1136 				if (a < addrlen)
1137 					continue;
1138 
1139 					/* check against hostname glob */
1140 			} else if (fnmatch(p, remotehost, FNM_CASEFOLD) != 0)
1141 				continue;
1142 		}
1143 
1144 					/* have a group specifier */
1145 		if ((p = strchr(word, ':')) != NULL) {
1146 			gid_t	*groups, *ng;
1147 			int	 gsize, i, found;
1148 
1149 			if (pw == NULL)
1150 				continue;	/* no match for unknown user */
1151 			*p++ = '\0';
1152 			groups = NULL;
1153 			gsize = 16;
1154 			do {
1155 				ng = realloc(groups, gsize * sizeof(gid_t));
1156 				if (ng == NULL)
1157 					fatal(
1158 					    "Local resource failure: realloc");
1159 				groups = ng;
1160 			} while (getgrouplist(pw->pw_name, pw->pw_gid,
1161 						groups, &gsize) == -1);
1162 			found = 0;
1163 			for (i = 0; i < gsize; i++) {
1164 				struct group *g;
1165 
1166 				if ((g = getgrgid(groups[i])) == NULL)
1167 					continue;
1168 				if (fnmatch(p, g->gr_name, 0) == 0) {
1169 					found = 1;
1170 					break;
1171 				}
1172 			}
1173 			free(groups);
1174 			if (!found)
1175 				continue;
1176 		}
1177 
1178 					/* check against username glob */
1179 		if (fnmatch(word, name, 0) != 0)
1180 			continue;
1181 
1182 		if (perm != NULL &&
1183 		    ((strcasecmp(perm, "allow") == 0) ||
1184 		     (strcasecmp(perm, "yes") == 0)))
1185 			retval = 1;
1186 		else if (perm != NULL &&
1187 		    ((strcasecmp(perm, "deny") == 0) ||
1188 		     (strcasecmp(perm, "no") == 0)))
1189 			retval = 0;
1190 		else
1191 			retval = !def;
1192 		if (!EMPTYSTR(class) && retclass != NULL)
1193 			*retclass = ftpd_strdup(class);
1194 		free(buf);
1195 		break;
1196 	}
1197 	(void) fclose(fd);
1198 	return (retval);
1199 }
1200 
1201 /*
1202  * Check if user is allowed by /etc/ftpusers
1203  * returns 1 for yes, 0 for no
1204  *
1205  * NOTE: needs struct passwd *pw setup (for checkuser())
1206  */
1207 static int
1208 checkaccess(const char *name)
1209 {
1210 
1211 	return (checkuser(_NAME_FTPUSERS, name, 1, 0, NULL));
1212 }
1213 
1214 static void
1215 login_utmp(const char *line, const char *name, const char *host,
1216     struct sockinet *haddr)
1217 {
1218 #if defined(SUPPORT_UTMPX) || defined(SUPPORT_UTMP)
1219 	struct timeval tv;
1220 	(void)gettimeofday(&tv, NULL);
1221 #endif
1222 #ifdef SUPPORT_UTMPX
1223 	if (doutmp) {
1224 		(void)memset(&utmpx, 0, sizeof(utmpx));
1225 		utmpx.ut_tv = tv;
1226 		utmpx.ut_pid = getpid();
1227 		utmpx.ut_id[0] = 'f';
1228 		utmpx.ut_id[1] = 't';
1229 		utmpx.ut_id[2] = 'p';
1230 		utmpx.ut_id[3] = '*';
1231 		utmpx.ut_type = USER_PROCESS;
1232 		(void)strncpy(utmpx.ut_name, name, sizeof(utmpx.ut_name));
1233 		(void)strncpy(utmpx.ut_line, line, sizeof(utmpx.ut_line));
1234 		(void)strncpy(utmpx.ut_host, host, sizeof(utmpx.ut_host));
1235 		(void)memcpy(&utmpx.ut_ss, &haddr->si_su, haddr->su_len);
1236 		ftpd_loginx(&utmpx);
1237 	}
1238 	if (dowtmp)
1239 		ftpd_logwtmpx(line, name, host, haddr, 0, USER_PROCESS);
1240 #endif
1241 #ifdef SUPPORT_UTMP
1242 	if (doutmp) {
1243 		(void)memset(&utmp, 0, sizeof(utmp));
1244 		(void)time(&utmp.ut_time);
1245 		(void)strncpy(utmp.ut_name, name, sizeof(utmp.ut_name));
1246 		(void)strncpy(utmp.ut_line, line, sizeof(utmp.ut_line));
1247 		(void)strncpy(utmp.ut_host, host, sizeof(utmp.ut_host));
1248 		ftpd_login(&utmp);
1249 	}
1250 	if (dowtmp)
1251 		ftpd_logwtmp(line, name, host);
1252 #endif
1253 }
1254 
1255 static void
1256 logout_utmp(void)
1257 {
1258 #ifdef SUPPORT_UTMPX
1259 	int okwtmpx = dowtmp;
1260 #endif
1261 #ifdef SUPPORT_UTMP
1262 	int okwtmp = dowtmp;
1263 #endif
1264 	if (logged_in) {
1265 #ifdef SUPPORT_UTMPX
1266 		if (doutmp)
1267 			okwtmpx &= ftpd_logoutx(ttyline, 0, DEAD_PROCESS);
1268 		if (okwtmpx)
1269 			ftpd_logwtmpx(ttyline, "", "", NULL, 0, DEAD_PROCESS);
1270 #endif
1271 #ifdef SUPPORT_UTMP
1272 		if (doutmp)
1273 			okwtmp &= ftpd_logout(ttyline);
1274 		if (okwtmp)
1275 			ftpd_logwtmp(ttyline, "", "");
1276 #endif
1277 	}
1278 }
1279 
1280 /*
1281  * Terminate login as previous user (if any), resetting state;
1282  * used when USER command is given or login fails.
1283  */
1284 static void
1285 end_login(void)
1286 {
1287 #ifdef USE_PAM
1288 	int e;
1289 #endif
1290 	logout_utmp();
1291 	show_chdir_messages(-1);		/* flush chdir cache */
1292 	if (pw != NULL && pw->pw_passwd != NULL)
1293 		memset(pw->pw_passwd, 0, strlen(pw->pw_passwd));
1294 	pw = NULL;
1295 	logged_in = 0;
1296 	askpasswd = 0;
1297 	permitted = 0;
1298 	quietmessages = 0;
1299 	gidcount = 0;
1300 	curclass.type = CLASS_REAL;
1301 	(void) seteuid((uid_t)0);
1302 #ifdef	LOGIN_CAP
1303 	setusercontext(NULL, getpwuid(0), 0,
1304 		       LOGIN_SETPRIORITY|LOGIN_SETRESOURCES|LOGIN_SETUMASK);
1305 #endif
1306 #ifdef USE_PAM
1307 	if (pamh) {
1308 		if ((e = pam_setcred(pamh, PAM_DELETE_CRED)) != PAM_SUCCESS)
1309 			syslog(LOG_ERR, "pam_setcred: %s",
1310 			    pam_strerror(pamh, e));
1311 		if ((e = pam_close_session(pamh,0)) != PAM_SUCCESS)
1312 			syslog(LOG_ERR, "pam_close_session: %s",
1313 			    pam_strerror(pamh, e));
1314 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS)
1315 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1316 		pamh = NULL;
1317 	}
1318 #endif
1319 }
1320 
1321 void
1322 pass(const char *passwd)
1323 {
1324 	do_pass(0, 0, passwd);
1325 }
1326 
1327 /*
1328  * Perform the passwd confirmation and login.
1329  *
1330  * If pass_checked is zero, confirm passwd is correct, & ignore pass_rval.
1331  * This is the traditional PASS implementation.
1332  *
1333  * If pass_checked is non-zero, use pass_rval and ignore passwd.
1334  * This is used by auth_pam() which has already parsed PASS.
1335  * This only applies to curclass.type != CLASS_GUEST.
1336  */
1337 static void
1338 do_pass(int pass_checked, int pass_rval, const char *passwd)
1339 {
1340 	int		 rval;
1341 	char		 root[MAXPATHLEN];
1342 #ifdef	LOGIN_CAP
1343 	login_cap_t *lc = NULL;
1344 #endif
1345 #ifdef USE_PAM
1346 	int e;
1347 #endif
1348 
1349 	rval = 1;
1350 
1351 	if (logged_in || askpasswd == 0) {
1352 		reply(503, "Login with USER first.");
1353 		return;
1354 	}
1355 	askpasswd = 0;
1356 	if (curclass.type != CLASS_GUEST) {
1357 			/* "ftp" is the only account allowed with no password */
1358 		if (pw == NULL) {
1359 			rval = 1;	/* failure below */
1360 			goto skip;
1361 		}
1362 		if (pass_checked) {	/* password validated in user() */
1363 			rval = pass_rval;
1364 			goto skip;
1365 		}
1366 #ifdef USE_PAM
1367 		syslog(LOG_ERR, "do_pass: USE_PAM shouldn't get here");
1368 		rval = 1;
1369 		goto skip;
1370 #endif
1371 #if defined(KERBEROS)
1372 		if (klogin(pw, "", hostname, (char *)passwd) == 0) {
1373 			rval = 0;
1374 			goto skip;
1375 		}
1376 #endif
1377 #if defined(KERBEROS5)
1378 		if (k5login(pw, "", hostname, (char *)passwd) == 0) {
1379 			rval = 0;
1380 			goto skip;
1381 		}
1382 #endif
1383 #ifdef SKEY
1384 		if (skey_haskey(pw->pw_name) == 0) {
1385 			char *p;
1386 			int r;
1387 
1388 			p = ftpd_strdup(passwd);
1389 			r = skey_passcheck(pw->pw_name, p);
1390 			free(p);
1391 			if (r != -1) {
1392 				rval = 0;
1393 				goto skip;
1394 			}
1395 		}
1396 #endif
1397 		if (!sflag)
1398 			rval = checkpassword(pw, passwd);
1399 		else
1400 			rval = 1;
1401 
1402  skip:
1403 
1404 			/*
1405 			 * If rval > 0, the user failed the authentication check
1406 			 * above.  If rval == 0, either Kerberos or local
1407 			 * authentication succeeded.
1408 			 */
1409 		if (rval) {
1410 			reply(530, "%s", rval == 2 ? "Password expired." :
1411 			    "Login incorrect.");
1412 			if (logging) {
1413 				syslog(LOG_NOTICE,
1414 				    "FTP LOGIN FAILED FROM %s", remoteloghost);
1415 				syslog(LOG_AUTHPRIV | LOG_NOTICE,
1416 				    "FTP LOGIN FAILED FROM %s, %s",
1417 				    remoteloghost, curname);
1418 			}
1419 			pw = NULL;
1420 			if (login_attempts++ >= 5) {
1421 				syslog(LOG_NOTICE,
1422 				    "repeated login failures from %s",
1423 				    remoteloghost);
1424 				exit(0);
1425 			}
1426 			return;
1427 		}
1428 	}
1429 
1430 			/* password ok; check if anything else prevents login */
1431 	if (! permitted) {
1432 		reply(530, "User %s may not use FTP.", pw->pw_name);
1433 		if (logging)
1434 			syslog(LOG_NOTICE, "FTP LOGIN REFUSED FROM %s, %s",
1435 			    remoteloghost, pw->pw_name);
1436 		goto bad;
1437 	}
1438 
1439 	login_attempts = 0;		/* this time successful */
1440 	if (setegid((gid_t)pw->pw_gid) < 0) {
1441 		reply(550, "Can't set gid.");
1442 		goto bad;
1443 	}
1444 #ifdef	LOGIN_CAP
1445 	if ((lc = login_getpwclass(pw)) != NULL) {
1446 #ifdef notyet
1447 		char	remote_ip[NI_MAXHOST];
1448 
1449 		if (getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
1450 			remote_ip, sizeof(remote_ip) - 1, NULL, 0,
1451 			NI_NUMERICHOST))
1452 				*remote_ip = 0;
1453 		remote_ip[sizeof(remote_ip) - 1] = 0;
1454 		if (!auth_hostok(lc, remotehost, remote_ip)) {
1455 			syslog(LOG_INFO|LOG_AUTH,
1456 			    "FTP LOGIN FAILED (HOST) as %s: permission denied.",
1457 			    pw->pw_name);
1458 			reply(530, "Permission denied.");
1459 			pw = NULL;
1460 			return;
1461 		}
1462 		if (!auth_timeok(lc, time(NULL))) {
1463 			reply(530, "Login not available right now.");
1464 			pw = NULL;
1465 			return;
1466 		}
1467 #endif
1468 	}
1469 	setsid();
1470 	setusercontext(lc, pw, 0,
1471 		LOGIN_SETLOGIN|LOGIN_SETGROUP|LOGIN_SETPRIORITY|
1472 		LOGIN_SETRESOURCES|LOGIN_SETUMASK);
1473 #else
1474 	(void) initgroups(pw->pw_name, pw->pw_gid);
1475 			/* cache groups for cmds.c::matchgroup() */
1476 #endif
1477 #ifdef USE_PAM
1478 	if (pamh) {
1479 		if ((e = pam_open_session(pamh, 0)) != PAM_SUCCESS) {
1480 			syslog(LOG_ERR, "pam_open_session: %s",
1481 			    pam_strerror(pamh, e));
1482 		} else if ((e = pam_setcred(pamh, PAM_ESTABLISH_CRED))
1483 		    != PAM_SUCCESS) {
1484 			syslog(LOG_ERR, "pam_setcred: %s",
1485 			    pam_strerror(pamh, e));
1486 		}
1487 	}
1488 #endif
1489 	gidcount = getgroups(0, NULL);
1490 	if (gidlist)
1491 		free(gidlist);
1492 	gidlist = malloc(gidcount * sizeof *gidlist);
1493 	gidcount = getgroups(gidcount, gidlist);
1494 
1495 	/* open utmp/wtmp before chroot */
1496 	login_utmp(ttyline, pw->pw_name, remotehost, &his_addr);
1497 
1498 	logged_in = 1;
1499 
1500 	connections = 1;
1501 	if (dopidfile)
1502 		count_users();
1503 	if (curclass.limit != -1 && connections > curclass.limit) {
1504 		if (! EMPTYSTR(curclass.limitfile))
1505 			(void)display_file(conffilename(curclass.limitfile),
1506 			    530);
1507 		reply(530,
1508 		    "User %s access denied, connection limit of " LLF
1509 		    " reached.",
1510 		    pw->pw_name, (LLT)curclass.limit);
1511 		syslog(LOG_NOTICE,
1512 		    "Maximum connection limit of " LLF
1513 		    " for class %s reached, login refused for %s",
1514 		    (LLT)curclass.limit, curclass.classname, pw->pw_name);
1515 		goto bad;
1516 	}
1517 
1518 	homedir[0] = '/';
1519 	switch (curclass.type) {
1520 	case CLASS_GUEST:
1521 			/*
1522 			 * We MUST do a chdir() after the chroot. Otherwise
1523 			 * the old current directory will be accessible as "."
1524 			 * outside the new root!
1525 			 */
1526 		format_path(root,
1527 		    curclass.chroot ? curclass.chroot :
1528 		    anondir ? anondir :
1529 		    pw->pw_dir);
1530 		format_path(homedir,
1531 		    curclass.homedir ? curclass.homedir :
1532 		    "/");
1533 		if (EMPTYSTR(homedir))
1534 			homedir[0] = '/';
1535 		if (EMPTYSTR(root) || chroot(root) < 0) {
1536 			syslog(LOG_NOTICE,
1537 			    "GUEST user %s: can't chroot to %s: %m",
1538 			    pw->pw_name, root);
1539 			goto bad_guest;
1540 		}
1541 		if (chdir(homedir) < 0) {
1542 			syslog(LOG_NOTICE,
1543 			    "GUEST user %s: can't chdir to %s: %m",
1544 			    pw->pw_name, homedir);
1545  bad_guest:
1546 			reply(550, "Can't set guest privileges.");
1547 			goto bad;
1548 		}
1549 		break;
1550 	case CLASS_CHROOT:
1551 		format_path(root,
1552 		    curclass.chroot ? curclass.chroot :
1553 		    pw->pw_dir);
1554 		format_path(homedir,
1555 		    curclass.homedir ? curclass.homedir :
1556 		    "/");
1557 		if (EMPTYSTR(homedir))
1558 			homedir[0] = '/';
1559 		if (EMPTYSTR(root) || chroot(root) < 0) {
1560 			syslog(LOG_NOTICE,
1561 			    "CHROOT user %s: can't chroot to %s: %m",
1562 			    pw->pw_name, root);
1563 			goto bad_chroot;
1564 		}
1565 		if (chdir(homedir) < 0) {
1566 			syslog(LOG_NOTICE,
1567 			    "CHROOT user %s: can't chdir to %s: %m",
1568 			    pw->pw_name, homedir);
1569  bad_chroot:
1570 			reply(550, "Can't change root.");
1571 			goto bad;
1572 		}
1573 		break;
1574 	case CLASS_REAL:
1575 			/* only chroot REAL if explicitly requested */
1576 		if (! EMPTYSTR(curclass.chroot)) {
1577 			format_path(root, curclass.chroot);
1578 			if (EMPTYSTR(root) || chroot(root) < 0) {
1579 				syslog(LOG_NOTICE,
1580 				    "REAL user %s: can't chroot to %s: %m",
1581 				    pw->pw_name, root);
1582 				goto bad_chroot;
1583 			}
1584 		}
1585 		format_path(homedir,
1586 		    curclass.homedir ? curclass.homedir :
1587 		    pw->pw_dir);
1588 		if (EMPTYSTR(homedir) || chdir(homedir) < 0) {
1589 			if (chdir("/") < 0) {
1590 				syslog(LOG_NOTICE,
1591 				    "REAL user %s: can't chdir to %s: %m",
1592 				    pw->pw_name,
1593 				    !EMPTYSTR(homedir) ?  homedir : "/");
1594 				reply(530,
1595 				    "User %s: can't change directory to %s.",
1596 				    pw->pw_name,
1597 				    !EMPTYSTR(homedir) ? homedir : "/");
1598 				goto bad;
1599 			} else {
1600 				reply(-230,
1601 				    "No directory! Logging in with home=/");
1602 				homedir[0] = '/';
1603 			}
1604 		}
1605 		break;
1606 	}
1607 #ifndef LOGIN_CAP
1608 	setsid();
1609 #if !defined(__minix)
1610 	setlogin(pw->pw_name);
1611 #endif
1612 #endif /* !defined(__minix) */
1613 	if (dropprivs ||
1614 	    (curclass.type != CLASS_REAL &&
1615 	    ntohs(ctrl_addr.su_port) > IPPORT_RESERVED + 1)) {
1616 		dropprivs++;
1617 		if (setgid((gid_t)pw->pw_gid) < 0) {
1618 			reply(550, "Can't set gid.");
1619 			goto bad;
1620 		}
1621 		if (setuid((uid_t)pw->pw_uid) < 0) {
1622 			reply(550, "Can't set uid.");
1623 			goto bad;
1624 		}
1625 	} else {
1626 		if (seteuid((uid_t)pw->pw_uid) < 0) {
1627 			reply(550, "Can't set uid.");
1628 			goto bad;
1629 		}
1630 	}
1631 	setenv("HOME", homedir, 1);
1632 
1633 	if (curclass.type == CLASS_GUEST && passwd[0] == '-')
1634 		quietmessages = 1;
1635 
1636 			/*
1637 			 * Display a login message, if it exists.
1638 			 * N.B. reply(230,) must follow the message.
1639 			 */
1640 	if (! EMPTYSTR(curclass.motd))
1641 		(void)display_file(conffilename(curclass.motd), 230);
1642 	show_chdir_messages(230);
1643 	if (curclass.type == CLASS_GUEST) {
1644 		char *p;
1645 
1646 		reply(230, "Guest login ok, access restrictions apply.");
1647 #if defined(HAVE_SETPROCTITLE)
1648 		snprintf(proctitle, sizeof(proctitle),
1649 		    "%s: anonymous/%s", remotehost, passwd);
1650 		setproctitle("%s", proctitle);
1651 #endif /* defined(HAVE_SETPROCTITLE) */
1652 		if (logging)
1653 			syslog(LOG_INFO,
1654 			"ANONYMOUS FTP LOGIN FROM %s, %s (class: %s, type: %s)",
1655 			    remoteloghost, passwd,
1656 			    curclass.classname, CURCLASSTYPE);
1657 			/* store guest password reply into pw_passwd */
1658 		REASSIGN(pw->pw_passwd, ftpd_strdup(passwd));
1659 		for (p = pw->pw_passwd; *p; p++)
1660 			if (!isgraph((unsigned char)*p))
1661 				*p = '_';
1662 	} else {
1663 		reply(230, "User %s logged in.", pw->pw_name);
1664 #if defined(HAVE_SETPROCTITLE)
1665 		snprintf(proctitle, sizeof(proctitle),
1666 		    "%s: %s", remotehost, pw->pw_name);
1667 		setproctitle("%s", proctitle);
1668 #endif /* defined(HAVE_SETPROCTITLE) */
1669 		if (logging)
1670 			syslog(LOG_INFO,
1671 			    "FTP LOGIN FROM %s as %s (class: %s, type: %s)",
1672 			    remoteloghost, pw->pw_name,
1673 			    curclass.classname, CURCLASSTYPE);
1674 	}
1675 	(void) umask(curclass.umask);
1676 #ifdef	LOGIN_CAP
1677 	login_close(lc);
1678 #endif
1679 	return;
1680 
1681  bad:
1682 #ifdef	LOGIN_CAP
1683 	login_close(lc);
1684 #endif
1685 			/* Forget all about it... */
1686 	end_login();
1687 }
1688 
1689 void
1690 retrieve(const char *argv[], const char *name)
1691 {
1692 	FILE *fin, *dout;
1693 	struct stat st;
1694 	int (*closefunc)(FILE *) = NULL;
1695 	int dolog, sendrv, closerv, stderrfd, isconversion, isdata, isls;
1696 	struct timeval start, finish, td, *tdp;
1697 #if !defined(__minix)
1698 	struct rusage rusage_before, rusage_after;
1699 #endif /* !defined(__minix) */
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 #if !defined(__minix)
1781 	(void)getrusage(RUSAGE_SELF, &rusage_before);
1782 #endif /* !defined(__minix) */
1783 	(void)gettimeofday(&start, NULL);
1784 	sendrv = send_data(fin, dout, &st, isdata);
1785 	(void)gettimeofday(&finish, NULL);
1786 #if !defined(__minix)
1787 	(void)getrusage(RUSAGE_SELF, &rusage_after);
1788 #endif /* !defined(__minix) */
1789 	closedataconn(dout);		/* close now to affect timing stats */
1790 	timersub(&finish, &start, &td);
1791 	tdp = &td;
1792  done:
1793 	if (dolog) {
1794 		logxfer("get", byte_count, name, NULL, tdp, error);
1795 #if !defined(__minix)
1796 		if (tdp != NULL)
1797 			logrusage(&rusage_before, &rusage_after);
1798 #endif /* !defined(__minix) */
1799 	}
1800 	closerv = (*closefunc)(fin);
1801 	if (sendrv == 0) {
1802 		FILE *errf;
1803 		struct stat sb;
1804 
1805 		if (!isls && argv != NULL && closerv != 0) {
1806 			reply(-226,
1807 			    "Command returned an exit status of %d",
1808 			    closerv);
1809 			if (isconversion)
1810 				syslog(LOG_WARNING,
1811 				    "retrieve command: '%s' returned %d",
1812 				    argv[0], closerv);
1813 		}
1814 		if (!isls && argv != NULL && stderrfd != -1 &&
1815 		    (fstat(stderrfd, &sb) == 0) && sb.st_size > 0 &&
1816 		    ((errf = fdopen(stderrfd, "r")) != NULL)) {
1817 			char *cp, line[LINE_MAX];
1818 
1819 			reply(-226, "Command error messages:");
1820 			rewind(errf);
1821 			while (fgets(line, sizeof(line), errf) != NULL) {
1822 				if ((cp = strchr(line, '\n')) != NULL)
1823 					*cp = '\0';
1824 				reply(0, "  %s", line);
1825 			}
1826 			(void) fflush(stdout);
1827 			(void) fclose(errf);
1828 				/* a reply(226,) must follow */
1829 		}
1830 		reply(226, "Transfer complete.");
1831 	}
1832  cleanupretrieve:
1833 	if (stderrfd != -1)
1834 		(void)close(stderrfd);
1835 	if (isconversion)
1836 		free(argv);
1837 }
1838 
1839 void
1840 store(const char *name, const char *fmode, int unique)
1841 {
1842 	FILE *fout, *din;
1843 	struct stat st;
1844 	int (*closefunc)(FILE *);
1845 	struct timeval start, finish, td, *tdp;
1846 	const char *desc, *error;
1847 
1848 	din = NULL;
1849 	desc = (*fmode == 'w') ? "put" : "append";
1850 	error = NULL;
1851 	if (unique && stat(name, &st) == 0 &&
1852 	    (name = gunique(name)) == NULL) {
1853 		logxfer(desc, -1, name, NULL, NULL,
1854 		    "cannot create unique file");
1855 		goto cleanupstore;
1856 	}
1857 
1858 	if (restart_point)
1859 		fmode = "r+";
1860 	fout = fopen(name, fmode);
1861 	closefunc = fclose;
1862 	tdp = NULL;
1863 	if (fout == NULL) {
1864 		perror_reply(553, name);
1865 		logxfer(desc, -1, name, NULL, NULL, strerror(errno));
1866 		goto cleanupstore;
1867 	}
1868 	byte_count = -1;
1869 	if (restart_point) {
1870 		if (type == TYPE_A) {
1871 			off_t i;
1872 			int c;
1873 
1874 			for (i = 0; i < restart_point; i++) {
1875 				if ((c=getc(fout)) == EOF) {
1876 					error = strerror(errno);
1877 					perror_reply(550, name);
1878 					goto done;
1879 				}
1880 				if (c == '\n')
1881 					i++;
1882 			}
1883 			/*
1884 			 * We must do this seek to "current" position
1885 			 * because we are changing from reading to
1886 			 * writing.
1887 			 */
1888 			if (fseek(fout, 0L, SEEK_CUR) < 0) {
1889 				error = strerror(errno);
1890 				perror_reply(550, name);
1891 				goto done;
1892 			}
1893 		} else if (lseek(fileno(fout), restart_point, SEEK_SET) < 0) {
1894 			error = strerror(errno);
1895 			perror_reply(550, name);
1896 			goto done;
1897 		}
1898 	}
1899 	din = dataconn(name, (off_t)-1, "r");
1900 	if (din == NULL)
1901 		goto done;
1902 	(void)gettimeofday(&start, NULL);
1903 	if (receive_data(din, fout) == 0) {
1904 		if (unique)
1905 			reply(226, "Transfer complete (unique file name:%s).",
1906 			    name);
1907 		else
1908 			reply(226, "Transfer complete.");
1909 	}
1910 	(void)gettimeofday(&finish, NULL);
1911 	closedataconn(din);		/* close now to affect timing stats */
1912 	timersub(&finish, &start, &td);
1913 	tdp = &td;
1914  done:
1915 	logxfer(desc, byte_count, name, NULL, tdp, error);
1916 	(*closefunc)(fout);
1917  cleanupstore:
1918 	;
1919 }
1920 
1921 static FILE *
1922 getdatasock(const char *fmode)
1923 {
1924 	int		on, s, t, tries;
1925 	in_port_t	port;
1926 
1927 	on = 1;
1928 	if (data >= 0)
1929 		return (fdopen(data, fmode));
1930 	if (! dropprivs)
1931 		(void) seteuid((uid_t)0);
1932 	s = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
1933 	if (s < 0)
1934 		goto bad;
1935 	if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR,
1936 	    (char *) &on, sizeof(on)) < 0)
1937 		goto bad;
1938 	if (setsockopt(s, SOL_SOCKET, SO_KEEPALIVE,
1939 	    (char *) &on, sizeof(on)) < 0)
1940 		goto bad;
1941 			/* anchor socket to avoid multi-homing problems */
1942 	data_source = ctrl_addr;
1943 			/*
1944 			 * By default source port for PORT connctions is
1945 			 * ctrlport-1 (see RFC959 section 5.2).
1946 			 * However, if privs have been dropped and that
1947 			 * would be < IPPORT_RESERVED, use a random port
1948 			 * instead.
1949 			 */
1950 	if (dataport)
1951 		port = dataport;
1952 	else
1953 		port = ntohs(ctrl_addr.su_port) - 1;
1954 	if (dropprivs && port < IPPORT_RESERVED)
1955 		port = 0;		/* use random port */
1956 	data_source.su_port = htons(port);
1957 
1958 	for (tries = 1; ; tries++) {
1959 		if (bind(s, (struct sockaddr *)&data_source.si_su,
1960 		    data_source.su_len) >= 0)
1961 			break;
1962 		if (errno != EADDRINUSE || tries > 10)
1963 			goto bad;
1964 		sleep(tries);
1965 	}
1966 	if (! dropprivs)
1967 		(void) seteuid((uid_t)pw->pw_uid);
1968 #ifdef IP_TOS
1969 	if (!mapped && ctrl_addr.su_family == AF_INET) {
1970 		on = IPTOS_THROUGHPUT;
1971 		if (setsockopt(s, IPPROTO_IP, IP_TOS, (char *)&on,
1972 			       sizeof(int)) < 0)
1973 			syslog(LOG_WARNING, "setsockopt (IP_TOS): %m");
1974 	}
1975 #endif
1976 	return (fdopen(s, fmode));
1977  bad:
1978 		/* Return the real value of errno (close may change it) */
1979 	t = errno;
1980 	if (! dropprivs)
1981 		(void) seteuid((uid_t)pw->pw_uid);
1982 	(void) close(s);
1983 	errno = t;
1984 	return (NULL);
1985 }
1986 
1987 FILE *
1988 dataconn(const char *name, off_t size, const char *fmode)
1989 {
1990 	char sizebuf[32];
1991 	FILE *file;
1992 	int retry, tos, keepalive, conerrno;
1993 
1994 	file_size = size;
1995 	byte_count = 0;
1996 	if (size != (off_t) -1)
1997 		(void)snprintf(sizebuf, sizeof(sizebuf), " (" LLF " byte%s)",
1998 		    (LLT)size, PLURAL(size));
1999 	else
2000 		sizebuf[0] = '\0';
2001 	if (pdata >= 0) {
2002 		struct sockinet from;
2003 		int s;
2004 		socklen_t fromlen = sizeof(from.su_len);
2005 
2006 		(void) alarm(curclass.timeout);
2007 		s = accept(pdata, (struct sockaddr *)&from.si_su, &fromlen);
2008 		(void) alarm(0);
2009 		if (s < 0) {
2010 			reply(425, "Can't open data connection.");
2011 			(void) close(pdata);
2012 			pdata = -1;
2013 			return (NULL);
2014 		}
2015 		(void) close(pdata);
2016 		pdata = s;
2017 #if !defined(__minix)
2018 		switch (from.su_family) {
2019 		case AF_INET:
2020 #ifdef IP_TOS
2021 			if (!mapped) {
2022 				tos = IPTOS_THROUGHPUT;
2023 				(void) setsockopt(s, IPPROTO_IP, IP_TOS,
2024 				    (char *)&tos, sizeof(int));
2025 			}
2026 			break;
2027 #endif
2028 		}
2029 #endif /* !defined(__minix) */
2030 		/* Set keepalives on the socket to detect dropped conns. */
2031 #ifdef SO_KEEPALIVE
2032 		keepalive = 1;
2033 		(void) setsockopt(s, SOL_SOCKET, SO_KEEPALIVE,
2034 		    (char *)&keepalive, sizeof(int));
2035 #endif
2036 		reply(150, "Opening %s mode data connection for '%s'%s.",
2037 		     type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
2038 		return (fdopen(pdata, fmode));
2039 	}
2040 	if (data >= 0) {
2041 		reply(125, "Using existing data connection for '%s'%s.",
2042 		    name, sizebuf);
2043 		usedefault = 1;
2044 		return (fdopen(data, fmode));
2045 	}
2046 	if (usedefault)
2047 		data_dest = his_addr;
2048 	usedefault = 1;
2049 	retry = conerrno = 0;
2050 	do {
2051 		file = getdatasock(fmode);
2052 		if (file == NULL) {
2053 			char hbuf[NI_MAXHOST];
2054 			char pbuf[NI_MAXSERV];
2055 
2056 			if (getnameinfo((struct sockaddr *)&data_source.si_su,
2057 			    data_source.su_len, hbuf, sizeof(hbuf), pbuf,
2058 			    sizeof(pbuf), NI_NUMERICHOST | NI_NUMERICSERV))
2059 				strlcpy(hbuf, "?", sizeof(hbuf));
2060 			reply(425, "Can't create data socket (%s,%s): %s.",
2061 			      hbuf, pbuf, strerror(errno));
2062 			return (NULL);
2063 		}
2064 		data = fileno(file);
2065 		conerrno = 0;
2066 		if (connect(data, (struct sockaddr *)&data_dest.si_su,
2067 		    data_dest.su_len) == 0)
2068 			break;
2069 		conerrno = errno;
2070 		(void) fclose(file);
2071 		file = NULL;
2072 		data = -1;
2073 		if (conerrno == EADDRINUSE) {
2074 			sleep((unsigned) swaitint);
2075 			retry += swaitint;
2076 		} else {
2077 			break;
2078 		}
2079 	} while (retry <= swaitmax);
2080 	if (conerrno != 0) {
2081 		perror_reply(425, "Can't build data connection");
2082 		return (NULL);
2083 	}
2084 	reply(150, "Opening %s mode data connection for '%s'%s.",
2085 	     type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
2086 	return (file);
2087 }
2088 
2089 void
2090 closedataconn(FILE *fd)
2091 {
2092 
2093 	if (fd == NULL)
2094 		return;
2095 	(void)fclose(fd);
2096 	data = -1;
2097 	if (pdata >= 0)
2098 		(void)close(pdata);
2099 	pdata = -1;
2100 }
2101 
2102 int
2103 write_data(int fd, char *buf, size_t size, off_t *bufrem,
2104     struct timeval *then, int isdata)
2105 {
2106 	struct timeval now, td;
2107 	ssize_t c;
2108 
2109 	while (size > 0) {
2110 		c = size;
2111 		if (curclass.writesize) {
2112 			if (curclass.writesize < c)
2113 				c = curclass.writesize;
2114 		}
2115 		if (curclass.rateget) {
2116 			if (*bufrem < c)
2117 				c = *bufrem;
2118 		}
2119 		(void) alarm(curclass.timeout);
2120 		c = write(fd, buf, c);
2121 		if (c <= 0)
2122 			return (1);
2123 		buf += c;
2124 		size -= c;
2125 		byte_count += c;
2126 		if (isdata) {
2127 			total_data_out += c;
2128 			total_data += c;
2129 		}
2130 		total_bytes_out += c;
2131 		total_bytes += c;
2132 		if (curclass.rateget) {
2133 			*bufrem -= c;
2134 			if (*bufrem == 0) {
2135 				(void)gettimeofday(&now, NULL);
2136 				timersub(&now, then, &td);
2137 				if (td.tv_sec == 0) {
2138 					usleep(1000000 - td.tv_usec);
2139 					(void)gettimeofday(then, NULL);
2140 				} else
2141 					*then = now;
2142 				*bufrem = curclass.rateget;
2143 			}
2144 		}
2145 	}
2146 	return (0);
2147 }
2148 
2149 static enum send_status
2150 send_data_with_read(int filefd, int netfd, const struct stat *st, int isdata)
2151 {
2152 	struct timeval then;
2153 	off_t bufrem;
2154 	ssize_t readsize;
2155 	char *buf;
2156 	int c, error;
2157 
2158 	if (curclass.readsize > 0)
2159 		readsize = curclass.readsize;
2160 	else
2161 		readsize = st->st_blksize;
2162 	if ((buf = malloc(readsize)) == NULL) {
2163 		perror_reply(451, "Local resource failure: malloc");
2164 		return (SS_NO_TRANSFER);
2165 	}
2166 
2167 	if (curclass.rateget) {
2168 		bufrem = curclass.rateget;
2169 		(void)gettimeofday(&then, NULL);
2170 	} else
2171 		bufrem = readsize;
2172 	for (;;) {
2173 		(void) alarm(curclass.timeout);
2174 		c = read(filefd, buf, readsize);
2175 		if (c == 0)
2176 			error = SS_SUCCESS;
2177 		else if (c < 0)
2178 			error = SS_FILE_ERROR;
2179 		else if (write_data(netfd, buf, c, &bufrem, &then, isdata))
2180 			error = SS_DATA_ERROR;
2181 		else if (urgflag && handleoobcmd())
2182 			error = SS_ABORTED;
2183 		else
2184 			continue;
2185 
2186 		free(buf);
2187 		return (error);
2188 	}
2189 }
2190 
2191 static enum send_status
2192 send_data_with_mmap(int filefd, int netfd, const struct stat *st, int isdata)
2193 {
2194 	struct timeval then;
2195 	off_t bufrem, filesize, off, origoff;
2196 	ssize_t mapsize, winsize;
2197 	int error, sendbufsize, sendlowat;
2198 	void *win;
2199 
2200 	bufrem = 0;
2201 	if (curclass.sendbufsize) {
2202 		sendbufsize = curclass.sendbufsize;
2203 		if (setsockopt(netfd, SOL_SOCKET, SO_SNDBUF,
2204 		    &sendbufsize, sizeof(int)) == -1)
2205 			syslog(LOG_WARNING, "setsockopt(SO_SNDBUF, %d): %m",
2206 			    sendbufsize);
2207 	}
2208 
2209 	if (curclass.sendlowat) {
2210 		sendlowat = curclass.sendlowat;
2211 		if (setsockopt(netfd, SOL_SOCKET, SO_SNDLOWAT,
2212 		    &sendlowat, sizeof(int)) == -1)
2213 			syslog(LOG_WARNING, "setsockopt(SO_SNDLOWAT, %d): %m",
2214 			    sendlowat);
2215 	}
2216 
2217 	winsize = curclass.mmapsize;
2218 	filesize = st->st_size;
2219 	if (ftpd_debug)
2220 		syslog(LOG_INFO, "mmapsize = " LLF ", writesize = " LLF,
2221 		    (LLT)winsize, (LLT)curclass.writesize);
2222 	if (winsize <= 0)
2223 		goto try_read;
2224 
2225 	off = lseek(filefd, (off_t)0, SEEK_CUR);
2226 	if (off == -1)
2227 		goto try_read;
2228 
2229 	origoff = off;
2230 	if (curclass.rateget) {
2231 		bufrem = curclass.rateget;
2232 		(void)gettimeofday(&then, NULL);
2233 	} else
2234 		bufrem = winsize;
2235 	while (1) {
2236 		mapsize = MIN(filesize - off, winsize);
2237 		if (mapsize == 0)
2238 			break;
2239 		win = mmap(NULL, mapsize, PROT_READ,
2240 		    MAP_FILE|MAP_SHARED, filefd, off);
2241 		if (win == MAP_FAILED) {
2242 			if (off == origoff)
2243 				goto try_read;
2244 			return (SS_FILE_ERROR);
2245 		}
2246 #ifndef __minix
2247 		(void) madvise(win, mapsize, MADV_SEQUENTIAL);
2248 #endif
2249 		error = write_data(netfd, win, mapsize, &bufrem, &then,
2250 		    isdata);
2251 #ifndef __minix
2252 		(void) madvise(win, mapsize, MADV_DONTNEED);
2253 #endif
2254 		munmap(win, mapsize);
2255 		if (urgflag && handleoobcmd())
2256 			return (SS_ABORTED);
2257 		if (error)
2258 			return (SS_DATA_ERROR);
2259 		off += mapsize;
2260 	}
2261 	return (SS_SUCCESS);
2262 
2263  try_read:
2264 	return (send_data_with_read(filefd, netfd, st, isdata));
2265 }
2266 
2267 /*
2268  * Transfer the contents of "instr" to "outstr" peer using the appropriate
2269  * encapsulation of the data subject to Mode, Structure, and Type.
2270  *
2271  * NB: Form isn't handled.
2272  */
2273 static int
2274 send_data(FILE *instr, FILE *outstr, const struct stat *st, int isdata)
2275 {
2276 	int	 c, filefd, netfd, rval;
2277 
2278 	urgflag = 0;
2279 	transflag = 1;
2280 	rval = -1;
2281 
2282 	switch (type) {
2283 
2284 	case TYPE_A:
2285  /* XXXLUKEM: rate limit ascii send (get) */
2286 		(void) alarm(curclass.timeout);
2287 		while ((c = getc(instr)) != EOF) {
2288 			if (urgflag && handleoobcmd())
2289 				goto cleanup_send_data;
2290 			byte_count++;
2291 			if (c == '\n') {
2292 				if (ferror(outstr))
2293 					goto data_err;
2294 				(void) putc('\r', outstr);
2295 				if (isdata) {
2296 					total_data_out++;
2297 					total_data++;
2298 				}
2299 				total_bytes_out++;
2300 				total_bytes++;
2301 			}
2302 			(void) putc(c, outstr);
2303 			if (isdata) {
2304 				total_data_out++;
2305 				total_data++;
2306 			}
2307 			total_bytes_out++;
2308 			total_bytes++;
2309 			if ((byte_count % 4096) == 0)
2310 				(void) alarm(curclass.timeout);
2311 		}
2312 		(void) alarm(0);
2313 		fflush(outstr);
2314 		if (ferror(instr))
2315 			goto file_err;
2316 		if (ferror(outstr))
2317 			goto data_err;
2318 		rval = 0;
2319 		goto cleanup_send_data;
2320 
2321 	case TYPE_I:
2322 	case TYPE_L:
2323 		filefd = fileno(instr);
2324 		netfd = fileno(outstr);
2325 		switch (send_data_with_mmap(filefd, netfd, st, isdata)) {
2326 
2327 		case SS_SUCCESS:
2328 			break;
2329 
2330 		case SS_ABORTED:
2331 		case SS_NO_TRANSFER:
2332 			goto cleanup_send_data;
2333 
2334 		case SS_FILE_ERROR:
2335 			goto file_err;
2336 
2337 		case SS_DATA_ERROR:
2338 			goto data_err;
2339 		}
2340 		rval = 0;
2341 		goto cleanup_send_data;
2342 
2343 	default:
2344 		reply(550, "Unimplemented TYPE %d in send_data", type);
2345 		goto cleanup_send_data;
2346 	}
2347 
2348  data_err:
2349 	(void) alarm(0);
2350 	perror_reply(426, "Data connection");
2351 	goto cleanup_send_data;
2352 
2353  file_err:
2354 	(void) alarm(0);
2355 	perror_reply(551, "Error on input file");
2356 	goto cleanup_send_data;
2357 
2358  cleanup_send_data:
2359 	(void) alarm(0);
2360 	transflag = 0;
2361 	urgflag = 0;
2362 	if (isdata) {
2363 		total_files_out++;
2364 		total_files++;
2365 	}
2366 	total_xfers_out++;
2367 	total_xfers++;
2368 	return (rval);
2369 }
2370 
2371 /*
2372  * Transfer data from peer to "outstr" using the appropriate encapulation of
2373  * the data subject to Mode, Structure, and Type.
2374  *
2375  * N.B.: Form isn't handled.
2376  */
2377 static int
2378 receive_data(FILE *instr, FILE *outstr)
2379 {
2380 	int	c, netfd, filefd, rval;
2381 	int	volatile bare_lfs;
2382 	off_t	byteswritten;
2383 	char	*buf;
2384 	ssize_t	readsize;
2385 	struct sigaction sa, sa_saved;
2386 	struct stat st;
2387 
2388 	memset(&sa, 0, sizeof(sa));
2389 	sigfillset(&sa.sa_mask);
2390 	sa.sa_flags = SA_RESTART;
2391 	sa.sa_handler = lostconn;
2392 	(void) sigaction(SIGALRM, &sa, &sa_saved);
2393 
2394 	bare_lfs = 0;
2395 	urgflag = 0;
2396 	transflag = 1;
2397 	rval = -1;
2398 	byteswritten = 0;
2399 	buf = NULL;
2400 
2401 #define FILESIZECHECK(x) \
2402 			do { \
2403 				if (curclass.maxfilesize != -1 && \
2404 				    (x) > curclass.maxfilesize) { \
2405 					errno = EFBIG; \
2406 					goto file_err; \
2407 				} \
2408 			} while (0)
2409 
2410 	switch (type) {
2411 
2412 	case TYPE_I:
2413 	case TYPE_L:
2414 		netfd = fileno(instr);
2415 		filefd = fileno(outstr);
2416 		(void) alarm(curclass.timeout);
2417 		if (curclass.readsize)
2418 			readsize = curclass.readsize;
2419 		else if (fstat(filefd, &st) != -1)
2420 			readsize = (ssize_t)st.st_blksize;
2421 		else
2422 			readsize = BUFSIZ;
2423 		if ((buf = malloc(readsize)) == NULL) {
2424 			perror_reply(451, "Local resource failure: malloc");
2425 			goto cleanup_recv_data;
2426 		}
2427 		if (curclass.rateput) {
2428 			while (1) {
2429 				int d;
2430 				struct timeval then, now, td;
2431 				off_t bufrem;
2432 
2433 				(void)gettimeofday(&then, NULL);
2434 				errno = c = d = 0;
2435 				for (bufrem = curclass.rateput; bufrem > 0; ) {
2436 					if ((c = read(netfd, buf,
2437 					    MIN(readsize, bufrem))) <= 0)
2438 						goto recvdone;
2439 					if (urgflag && handleoobcmd())
2440 						goto cleanup_recv_data;
2441 					FILESIZECHECK(byte_count + c);
2442 					if ((d = write(filefd, buf, c)) != c)
2443 						goto file_err;
2444 					(void) alarm(curclass.timeout);
2445 					bufrem -= c;
2446 					byte_count += c;
2447 					total_data_in += c;
2448 					total_data += c;
2449 					total_bytes_in += c;
2450 					total_bytes += c;
2451 				}
2452 				(void)gettimeofday(&now, NULL);
2453 				timersub(&now, &then, &td);
2454 				if (td.tv_sec == 0)
2455 					usleep(1000000 - td.tv_usec);
2456 			}
2457 		} else {
2458 			while ((c = read(netfd, buf, readsize)) > 0) {
2459 				if (urgflag && handleoobcmd())
2460 					goto cleanup_recv_data;
2461 				FILESIZECHECK(byte_count + c);
2462 				if (write(filefd, buf, c) != c)
2463 					goto file_err;
2464 				(void) alarm(curclass.timeout);
2465 				byte_count += c;
2466 				total_data_in += c;
2467 				total_data += c;
2468 				total_bytes_in += c;
2469 				total_bytes += c;
2470 			}
2471 		}
2472  recvdone:
2473 		if (c < 0)
2474 			goto data_err;
2475 		rval = 0;
2476 		goto cleanup_recv_data;
2477 
2478 	case TYPE_E:
2479 		reply(553, "TYPE E not implemented.");
2480 		goto cleanup_recv_data;
2481 
2482 	case TYPE_A:
2483 		(void) alarm(curclass.timeout);
2484  /* XXXLUKEM: rate limit ascii receive (put) */
2485 		while ((c = getc(instr)) != EOF) {
2486 			if (urgflag && handleoobcmd())
2487 				goto cleanup_recv_data;
2488 			byte_count++;
2489 			total_data_in++;
2490 			total_data++;
2491 			total_bytes_in++;
2492 			total_bytes++;
2493 			if ((byte_count % 4096) == 0)
2494 				(void) alarm(curclass.timeout);
2495 			if (c == '\n')
2496 				bare_lfs++;
2497 			while (c == '\r') {
2498 				if (ferror(outstr))
2499 					goto data_err;
2500 				if ((c = getc(instr)) != '\n') {
2501 					byte_count++;
2502 					total_data_in++;
2503 					total_data++;
2504 					total_bytes_in++;
2505 					total_bytes++;
2506 					if ((byte_count % 4096) == 0)
2507 						(void) alarm(curclass.timeout);
2508 					byteswritten++;
2509 					FILESIZECHECK(byteswritten);
2510 					(void) putc ('\r', outstr);
2511 					if (c == '\0' || c == EOF)
2512 						goto contin2;
2513 				}
2514 			}
2515 			byteswritten++;
2516 			FILESIZECHECK(byteswritten);
2517 			(void) putc(c, outstr);
2518  contin2:	;
2519 		}
2520 		(void) alarm(0);
2521 		fflush(outstr);
2522 		if (ferror(instr))
2523 			goto data_err;
2524 		if (ferror(outstr))
2525 			goto file_err;
2526 		if (bare_lfs) {
2527 			reply(-226,
2528 			    "WARNING! %d bare linefeeds received in ASCII mode",
2529 			    bare_lfs);
2530 			reply(0, "File may not have transferred correctly.");
2531 		}
2532 		rval = 0;
2533 		goto cleanup_recv_data;
2534 
2535 	default:
2536 		reply(550, "Unimplemented TYPE %d in receive_data", type);
2537 		goto cleanup_recv_data;
2538 	}
2539 #undef FILESIZECHECK
2540 
2541  data_err:
2542 	(void) alarm(0);
2543 	perror_reply(426, "Data Connection");
2544 	goto cleanup_recv_data;
2545 
2546  file_err:
2547 	(void) alarm(0);
2548 	perror_reply(452, "Error writing file");
2549 	goto cleanup_recv_data;
2550 
2551  cleanup_recv_data:
2552 	(void) alarm(0);
2553 	(void) sigaction(SIGALRM, &sa_saved, NULL);
2554 	if (buf)
2555 		free(buf);
2556 	transflag = 0;
2557 	urgflag = 0;
2558 	total_files_in++;
2559 	total_files++;
2560 	total_xfers_in++;
2561 	total_xfers++;
2562 	return (rval);
2563 }
2564 
2565 void
2566 statcmd(void)
2567 {
2568 	struct sockinet *su = NULL;
2569 	static char hbuf[NI_MAXHOST], sbuf[NI_MAXSERV];
2570 	unsigned char *a, *p;
2571 	int ispassive, af;
2572 	off_t otbi, otbo, otb;
2573 
2574 	a = p = NULL;
2575 
2576 	reply(-211, "%s FTP server status:", hostname);
2577 	reply(0, "Version: %s", EMPTYSTR(version) ? "<suppressed>" : version);
2578 	hbuf[0] = '\0';
2579 	if (!getnameinfo((struct sockaddr *)&his_addr.si_su, his_addr.su_len,
2580 			hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST)
2581 	    && strcmp(remotehost, hbuf) != 0)
2582 		reply(0, "Connected to %s (%s)", remotehost, hbuf);
2583 	else
2584 		reply(0, "Connected to %s", remotehost);
2585 
2586 	if (logged_in) {
2587 		if (curclass.type == CLASS_GUEST)
2588 			reply(0, "Logged in anonymously");
2589 		else
2590 			reply(0, "Logged in as %s%s", pw->pw_name,
2591 			    curclass.type == CLASS_CHROOT ? " (chroot)" : "");
2592 	} else if (askpasswd)
2593 		reply(0, "Waiting for password");
2594 	else
2595 		reply(0, "Waiting for user name");
2596 	cprintf(stdout, "    TYPE: %s", typenames[type]);
2597 	if (type == TYPE_A || type == TYPE_E)
2598 		cprintf(stdout, ", FORM: %s", formnames[form]);
2599 	if (type == TYPE_L) {
2600 #if NBBY == 8
2601 		cprintf(stdout, " %d", NBBY);
2602 #else
2603 			/* XXX: `bytesize' needs to be defined in this case */
2604 		cprintf(stdout, " %d", bytesize);
2605 #endif
2606 	}
2607 	cprintf(stdout, "; STRUcture: %s; transfer MODE: %s\r\n",
2608 	    strunames[stru], modenames[mode]);
2609 	ispassive = 0;
2610 	if (data != -1) {
2611 		reply(0, "Data connection open");
2612 		su = NULL;
2613 	} else if (pdata != -1) {
2614 		reply(0, "in Passive mode");
2615 		if (curclass.advertise.su_len != 0)
2616 			su = &curclass.advertise;
2617 		else
2618 			su = &pasv_addr;
2619 		ispassive = 1;
2620 		goto printaddr;
2621 	} else if (usedefault == 0) {
2622 		su = (struct sockinet *)&data_dest;
2623 
2624 		if (epsvall) {
2625 			reply(0, "EPSV only mode (EPSV ALL)");
2626 			goto epsvonly;
2627 		}
2628  printaddr:
2629 							/* PASV/PORT */
2630 		if (su->su_family == AF_INET) {
2631 			a = (unsigned char *) &su->su_addr;
2632 			p = (unsigned char *) &su->su_port;
2633 #define UC(b) (((int) b) & 0xff)
2634 			reply(0, "%s (%d,%d,%d,%d,%d,%d)",
2635 				ispassive ? "PASV" : "PORT" ,
2636 				UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
2637 				UC(p[0]), UC(p[1]));
2638 		}
2639 
2640 							/* LPSV/LPRT */
2641 	    {
2642 		int alen, i;
2643 
2644 		alen = 0;
2645 		switch (su->su_family) {
2646 		case AF_INET:
2647 			a = (unsigned char *) &su->su_addr;
2648 			p = (unsigned char *) &su->su_port;
2649 			alen = sizeof(su->su_addr);
2650 			af = 4;
2651 			break;
2652 #ifdef INET6
2653 		case AF_INET6:
2654 			a = (unsigned char *) &su->su_6addr;
2655 			p = (unsigned char *) &su->su_port;
2656 			alen = sizeof(su->su_6addr);
2657 			af = 6;
2658 			break;
2659 #endif
2660 		default:
2661 			af = 0;
2662 			break;
2663 		}
2664 		if (af) {
2665 			cprintf(stdout, "    %s (%d,%d",
2666 			    ispassive ? "LPSV" : "LPRT", af, alen);
2667 			for (i = 0; i < alen; i++)
2668 				cprintf(stdout, ",%d", UC(a[i]));
2669 			cprintf(stdout, ",%d,%d,%d)\r\n",
2670 			    2, UC(p[0]), UC(p[1]));
2671 #undef UC
2672 		}
2673 	    }
2674 
2675 		/* EPRT/EPSV */
2676  epsvonly:
2677 		af = af2epsvproto(su->su_family);
2678 		hbuf[0] = '\0';
2679 		if (af > 0) {
2680 			struct sockinet tmp;
2681 
2682 			tmp = *su;
2683 #ifdef INET6
2684 			if (tmp.su_family == AF_INET6)
2685 				tmp.su_scope_id = 0;
2686 #endif
2687 			if (getnameinfo((struct sockaddr *)&tmp.si_su,
2688 			    tmp.su_len, hbuf, sizeof(hbuf), sbuf, sizeof(sbuf),
2689 			    NI_NUMERICHOST | NI_NUMERICSERV) == 0)
2690 				reply(0, "%s (|%d|%s|%s|)",
2691 				    ispassive ? "EPSV" : "EPRT",
2692 				    af, hbuf, sbuf);
2693 		}
2694 	} else
2695 		reply(0, "No data connection");
2696 
2697 	if (logged_in) {
2698 		reply(0,
2699 		    "Data sent:        " LLF " byte%s in " LLF " file%s",
2700 		    (LLT)total_data_out, PLURAL(total_data_out),
2701 		    (LLT)total_files_out, PLURAL(total_files_out));
2702 		reply(0,
2703 		    "Data received:    " LLF " byte%s in " LLF " file%s",
2704 		    (LLT)total_data_in, PLURAL(total_data_in),
2705 		    (LLT)total_files_in, PLURAL(total_files_in));
2706 		reply(0,
2707 		    "Total data:       " LLF " byte%s in " LLF " file%s",
2708 		    (LLT)total_data, PLURAL(total_data),
2709 		    (LLT)total_files, PLURAL(total_files));
2710 	}
2711 	otbi = total_bytes_in;
2712 	otbo = total_bytes_out;
2713 	otb = total_bytes;
2714 	reply(0, "Traffic sent:     " LLF " byte%s in " LLF " transfer%s",
2715 	    (LLT)otbo, PLURAL(otbo),
2716 	    (LLT)total_xfers_out, PLURAL(total_xfers_out));
2717 	reply(0, "Traffic received: " LLF " byte%s in " LLF " transfer%s",
2718 	    (LLT)otbi, PLURAL(otbi),
2719 	    (LLT)total_xfers_in, PLURAL(total_xfers_in));
2720 	reply(0, "Total traffic:    " LLF " byte%s in " LLF " transfer%s",
2721 	    (LLT)otb, PLURAL(otb),
2722 	    (LLT)total_xfers, PLURAL(total_xfers));
2723 
2724 	if (logged_in && !CURCLASS_FLAGS_ISSET(private)) {
2725 		struct ftpconv *cp;
2726 
2727 		reply(0, "%s", "");
2728 		reply(0, "Class: %s, type: %s",
2729 		    curclass.classname, CURCLASSTYPE);
2730 		reply(0, "Check PORT/LPRT commands: %sabled",
2731 		    CURCLASS_FLAGS_ISSET(checkportcmd) ? "en" : "dis");
2732 		if (! EMPTYSTR(curclass.display))
2733 			reply(0, "Display file: %s", curclass.display);
2734 		if (! EMPTYSTR(curclass.notify))
2735 			reply(0, "Notify fileglob: %s", curclass.notify);
2736 		reply(0, "Idle timeout: " LLF ", maximum timeout: " LLF,
2737 		    (LLT)curclass.timeout, (LLT)curclass.maxtimeout);
2738 		reply(0, "Current connections: %d", connections);
2739 		if (curclass.limit == -1)
2740 			reply(0, "Maximum connections: unlimited");
2741 		else
2742 			reply(0, "Maximum connections: " LLF,
2743 			    (LLT)curclass.limit);
2744 		if (curclass.limitfile)
2745 			reply(0, "Connection limit exceeded message file: %s",
2746 			    conffilename(curclass.limitfile));
2747 		if (! EMPTYSTR(curclass.chroot))
2748 			reply(0, "Chroot format: %s", curclass.chroot);
2749 		reply(0, "Deny bad ftpusers(5) quickly: %sabled",
2750 		    CURCLASS_FLAGS_ISSET(denyquick) ? "en" : "dis");
2751 		if (! EMPTYSTR(curclass.homedir))
2752 			reply(0, "Homedir format: %s", curclass.homedir);
2753 		if (curclass.maxfilesize == -1)
2754 			reply(0, "Maximum file size: unlimited");
2755 		else
2756 			reply(0, "Maximum file size: " LLF,
2757 			    (LLT)curclass.maxfilesize);
2758 		if (! EMPTYSTR(curclass.motd))
2759 			reply(0, "MotD file: %s", conffilename(curclass.motd));
2760 		reply(0,
2761 	    "Modify commands (CHMOD, DELE, MKD, RMD, RNFR, UMASK): %sabled",
2762 		    CURCLASS_FLAGS_ISSET(modify) ? "en" : "dis");
2763 		reply(0, "Upload commands (APPE, STOR, STOU): %sabled",
2764 		    CURCLASS_FLAGS_ISSET(upload) ? "en" : "dis");
2765 		reply(0, "Sanitize file names: %sabled",
2766 		    CURCLASS_FLAGS_ISSET(sanenames) ? "en" : "dis");
2767 		reply(0, "PASV/LPSV/EPSV connections: %sabled",
2768 		    CURCLASS_FLAGS_ISSET(passive) ? "en" : "dis");
2769 		if (curclass.advertise.su_len != 0) {
2770 			char buf[50];	/* big enough for IPv6 address */
2771 			const char *bp;
2772 
2773 			bp = inet_ntop(curclass.advertise.su_family,
2774 			    (void *)&curclass.advertise.su_addr,
2775 			    buf, sizeof(buf));
2776 			if (bp != NULL)
2777 				reply(0, "PASV advertise address: %s", bp);
2778 		}
2779 		if (curclass.portmin && curclass.portmax)
2780 			reply(0, "PASV port range: " LLF " - " LLF,
2781 			    (LLT)curclass.portmin, (LLT)curclass.portmax);
2782 		if (curclass.rateget)
2783 			reply(0, "Rate get limit: " LLF " bytes/sec",
2784 			    (LLT)curclass.rateget);
2785 		else
2786 			reply(0, "Rate get limit: disabled");
2787 		if (curclass.rateput)
2788 			reply(0, "Rate put limit: " LLF " bytes/sec",
2789 			    (LLT)curclass.rateput);
2790 		else
2791 			reply(0, "Rate put limit: disabled");
2792 		if (curclass.mmapsize)
2793 			reply(0, "Mmap size: " LLF, (LLT)curclass.mmapsize);
2794 		else
2795 			reply(0, "Mmap size: disabled");
2796 		if (curclass.readsize)
2797 			reply(0, "Read size: " LLF, (LLT)curclass.readsize);
2798 		else
2799 			reply(0, "Read size: default");
2800 		if (curclass.writesize)
2801 			reply(0, "Write size: " LLF, (LLT)curclass.writesize);
2802 		else
2803 			reply(0, "Write size: default");
2804 		if (curclass.recvbufsize)
2805 			reply(0, "Receive buffer size: " LLF,
2806 			    (LLT)curclass.recvbufsize);
2807 		else
2808 			reply(0, "Receive buffer size: default");
2809 		if (curclass.sendbufsize)
2810 			reply(0, "Send buffer size: " LLF,
2811 			    (LLT)curclass.sendbufsize);
2812 		else
2813 			reply(0, "Send buffer size: default");
2814 		if (curclass.sendlowat)
2815 			reply(0, "Send low water mark: " LLF,
2816 			    (LLT)curclass.sendlowat);
2817 		else
2818 			reply(0, "Send low water mark: default");
2819 		reply(0, "Umask: %.04o", curclass.umask);
2820 		for (cp = curclass.conversions; cp != NULL; cp=cp->next) {
2821 			if (cp->suffix == NULL || cp->types == NULL ||
2822 			    cp->command == NULL)
2823 				continue;
2824 			reply(0, "Conversion: %s [%s] disable: %s, command: %s",
2825 			    cp->suffix, cp->types, cp->disable, cp->command);
2826 		}
2827 	}
2828 
2829 	reply(211, "End of status");
2830 }
2831 
2832 void
2833 fatal(const char *s)
2834 {
2835 
2836 	reply(451, "Error in server: %s\n", s);
2837 	reply(221, "Closing connection due to server error.");
2838 	dologout(0);
2839 	/* NOTREACHED */
2840 }
2841 
2842 /*
2843  * reply() --
2844  *	depending on the value of n, display fmt with a trailing CRLF and
2845  *	prefix of:
2846  *	n < -1		prefix the message with abs(n) + "-"	(initial line)
2847  *	n == 0		prefix the message with 4 spaces	(middle lines)
2848  *	n >  0		prefix the message with n + " "		(final line)
2849  */
2850 void
2851 reply(int n, const char *fmt, ...)
2852 {
2853 	char	msg[MAXPATHLEN * 2 + 100];
2854 	size_t	b;
2855 	va_list	ap;
2856 
2857 	if (n == 0)
2858 		b = snprintf(msg, sizeof(msg), "    ");
2859 	else if (n < 0)
2860 		b = snprintf(msg, sizeof(msg), "%d-", -n);
2861 	else
2862 		b = snprintf(msg, sizeof(msg), "%d ", n);
2863 	va_start(ap, fmt);
2864 	vsnprintf(msg + b, sizeof(msg) - b, fmt, ap);
2865 	va_end(ap);
2866 	cprintf(stdout, "%s\r\n", msg);
2867 	(void)fflush(stdout);
2868 	if (ftpd_debug)
2869 		syslog(LOG_DEBUG, "<--- %s", msg);
2870 }
2871 
2872 static void
2873 logremotehost(struct sockinet *who)
2874 {
2875 
2876 #if defined(HAVE_SOCKADDR_SNPRINTF)
2877 	char abuf[BUFSIZ];
2878 #endif
2879 
2880 	struct sockaddr *sa = (struct sockaddr *)&who->si_su;
2881 	if (getnameinfo(sa, who->su_len, remotehost, sizeof(remotehost), NULL,
2882 	    0, getnameopts))
2883 		strlcpy(remotehost, "?", sizeof(remotehost));
2884 #if defined(HAVE_SOCKADDR_SNPRINTF)
2885 	sockaddr_snprintf(abuf, sizeof(abuf), "%a", sa);
2886 	snprintf(remoteloghost, sizeof(remoteloghost), "%s(%s)", remotehost,
2887 	    abuf);
2888 #else
2889 	strlcpy(remoteloghost, remotehost, sizeof(remoteloghost));
2890 #endif
2891 
2892 #if defined(HAVE_SETPROCTITLE)
2893 	snprintf(proctitle, sizeof(proctitle), "%s: connected", remotehost);
2894 	setproctitle("%s", proctitle);
2895 #endif /* defined(HAVE_SETPROCTITLE) */
2896 	if (logging)
2897 		syslog(LOG_INFO, "connection from %s to %s",
2898 		    remoteloghost, hostname);
2899 }
2900 
2901 /*
2902  * Record logout in wtmp file and exit with supplied status.
2903  * NOTE: because this is called from signal handlers it cannot
2904  *       use stdio (or call other functions that use stdio).
2905  */
2906 void
2907 dologout(int status)
2908 {
2909 	/*
2910 	* Prevent reception of SIGURG from resulting in a resumption
2911 	* back to the main program loop.
2912 	*/
2913 	transflag = 0;
2914 	logout_utmp();
2915 	if (logged_in) {
2916 #ifdef KERBEROS
2917 		if (!notickets && krbtkfile_env)
2918 			unlink(krbtkfile_env);
2919 #endif
2920 	}
2921 	/* beware of flushing buffers after a SIGPIPE */
2922 	if (xferlogfd != -1)
2923 		close(xferlogfd);
2924 	_exit(status);
2925 }
2926 
2927 void
2928 abor(void)
2929 {
2930 
2931 	if (!transflag)
2932 		return;
2933 	tmpline[0] = '\0';
2934 	is_oob = 0;
2935 	reply(426, "Transfer aborted. Data connection closed.");
2936 	reply(226, "Abort successful");
2937 	transflag = 0;		/* flag that the transfer has aborted */
2938 }
2939 
2940 void
2941 statxfer(void)
2942 {
2943 
2944 	if (!transflag)
2945 		return;
2946 	tmpline[0] = '\0';
2947 	is_oob = 0;
2948 	if (file_size != (off_t) -1)
2949 		reply(213,
2950 		    "Status: " LLF " of " LLF " byte%s transferred",
2951 		    (LLT)byte_count, (LLT)file_size,
2952 		    PLURAL(byte_count));
2953 	else
2954 		reply(213, "Status: " LLF " byte%s transferred",
2955 		    (LLT)byte_count, PLURAL(byte_count));
2956 }
2957 
2958 /*
2959  * Call when urgflag != 0 to handle Out Of Band commands.
2960  * Returns non zero if the OOB command aborted the transfer
2961  * by setting transflag to 0. (c.f., "ABOR").
2962  */
2963 static int
2964 handleoobcmd(void)
2965 {
2966 	char *cp;
2967 	int ret;
2968 
2969 	if (!urgflag)
2970 		return (0);
2971 	urgflag = 0;
2972 	/* only process if transfer occurring */
2973 	if (!transflag)
2974 		return (0);
2975 	cp = tmpline;
2976 	ret = get_line(cp, sizeof(tmpline)-1, stdin);
2977 	if (ret == -1) {
2978 		reply(221, "You could at least say goodbye.");
2979 		dologout(0);
2980 	} else if (ret == -2) {
2981 		/* Ignore truncated command */
2982 		/* XXX: abort xfer with "500 command too long", & return 1 ? */
2983 		return 0;
2984 	}
2985 		/*
2986 		 * Manually parse OOB commands, because we can't
2987 		 * recursively call the yacc parser...
2988 		 */
2989 	if (strcasecmp(cp, "ABOR\r\n") == 0) {
2990 		abor();
2991 	} else if (strcasecmp(cp, "STAT\r\n") == 0) {
2992 		statxfer();
2993 	} else {
2994 		/* XXX: error with "500 unknown command" ? */
2995 	}
2996 	return (transflag == 0);
2997 }
2998 
2999 static int
3000 bind_pasv_addr(void)
3001 {
3002 	static int passiveport;
3003 	int port, len;
3004 
3005 	len = pasv_addr.su_len;
3006 	if (curclass.portmin == 0 && curclass.portmax == 0) {
3007 		pasv_addr.su_port = 0;
3008 		return (bind(pdata, (struct sockaddr *)&pasv_addr.si_su, len));
3009 	}
3010 
3011 	if (passiveport == 0) {
3012 		srand(getpid());
3013 		passiveport = rand() % (curclass.portmax - curclass.portmin)
3014 		    + curclass.portmin;
3015 	}
3016 
3017 	port = passiveport;
3018 	while (1) {
3019 		port++;
3020 		if (port > curclass.portmax)
3021 			port = curclass.portmin;
3022 		else if (port == passiveport) {
3023 			errno = EAGAIN;
3024 			return (-1);
3025 		}
3026 		pasv_addr.su_port = htons(port);
3027 		if (bind(pdata, (struct sockaddr *)&pasv_addr.si_su, len) == 0)
3028 			break;
3029 		if (errno != EADDRINUSE)
3030 			return (-1);
3031 	}
3032 	passiveport = port;
3033 	return (0);
3034 }
3035 
3036 /*
3037  * Note: a response of 425 is not mentioned as a possible response to
3038  *	the PASV command in RFC959. However, it has been blessed as
3039  *	a legitimate response by Jon Postel in a telephone conversation
3040  *	with Rick Adams on 25 Jan 89.
3041  */
3042 void
3043 passive(void)
3044 {
3045 	socklen_t len;
3046 	int recvbufsize;
3047 	char *p, *a;
3048 
3049 	if (pdata >= 0)
3050 		close(pdata);
3051 	pdata = socket(AF_INET, SOCK_STREAM, 0);
3052 	if (pdata < 0 || !logged_in) {
3053 		perror_reply(425, "Can't open passive connection");
3054 		return;
3055 	}
3056 	pasv_addr = ctrl_addr;
3057 
3058 	if (bind_pasv_addr() < 0)
3059 		goto pasv_error;
3060 	len = pasv_addr.su_len;
3061 	if (getsockname(pdata, (struct sockaddr *) &pasv_addr.si_su, &len) < 0)
3062 		goto pasv_error;
3063 	pasv_addr.su_len = len;
3064 	if (curclass.recvbufsize) {
3065 		recvbufsize = curclass.recvbufsize;
3066 		if (setsockopt(pdata, SOL_SOCKET, SO_RCVBUF, &recvbufsize,
3067 			       sizeof(int)) == -1)
3068 			syslog(LOG_WARNING, "setsockopt(SO_RCVBUF, %d): %m",
3069 			       recvbufsize);
3070 	}
3071 	if (listen(pdata, 1) < 0)
3072 		goto pasv_error;
3073 	if (curclass.advertise.su_len != 0)
3074 		a = (char *) &curclass.advertise.su_addr;
3075 	else
3076 		a = (char *) &pasv_addr.su_addr;
3077 	p = (char *) &pasv_addr.su_port;
3078 
3079 #define UC(b) (((int) b) & 0xff)
3080 
3081 	reply(227, "Entering Passive Mode (%d,%d,%d,%d,%d,%d)", UC(a[0]),
3082 		UC(a[1]), UC(a[2]), UC(a[3]), UC(p[0]), UC(p[1]));
3083 	return;
3084 
3085  pasv_error:
3086 	(void) close(pdata);
3087 	pdata = -1;
3088 	perror_reply(425, "Can't open passive connection");
3089 	return;
3090 }
3091 
3092 /*
3093  * convert protocol identifier to/from AF
3094  */
3095 int
3096 lpsvproto2af(int proto)
3097 {
3098 
3099 	switch (proto) {
3100 	case 4:
3101 		return AF_INET;
3102 #ifdef INET6
3103 	case 6:
3104 		return AF_INET6;
3105 #endif
3106 	default:
3107 		return -1;
3108 	}
3109 }
3110 
3111 int
3112 af2lpsvproto(int af)
3113 {
3114 
3115 	switch (af) {
3116 	case AF_INET:
3117 		return 4;
3118 #ifdef INET6
3119 	case AF_INET6:
3120 		return 6;
3121 #endif
3122 	default:
3123 		return -1;
3124 	}
3125 }
3126 
3127 int
3128 epsvproto2af(int proto)
3129 {
3130 
3131 	switch (proto) {
3132 	case 1:
3133 		return AF_INET;
3134 #ifdef INET6
3135 	case 2:
3136 		return AF_INET6;
3137 #endif
3138 	default:
3139 		return -1;
3140 	}
3141 }
3142 
3143 int
3144 af2epsvproto(int af)
3145 {
3146 
3147 	switch (af) {
3148 	case AF_INET:
3149 		return 1;
3150 #ifdef INET6
3151 	case AF_INET6:
3152 		return 2;
3153 #endif
3154 	default:
3155 		return -1;
3156 	}
3157 }
3158 
3159 /*
3160  * 228 Entering Long Passive Mode (af, hal, h1, h2, h3,..., pal, p1, p2...)
3161  * 229 Entering Extended Passive Mode (|||port|)
3162  */
3163 void
3164 long_passive(const char *cmd, int pf)
3165 {
3166 	socklen_t len;
3167 	char *p, *a;
3168 
3169 	if (!logged_in) {
3170 		syslog(LOG_NOTICE, "long passive but not logged in");
3171 		reply(503, "Login with USER first.");
3172 		return;
3173 	}
3174 
3175 	if (pf != PF_UNSPEC && ctrl_addr.su_family != pf) {
3176 		/*
3177 		 * XXX: only EPRT/EPSV ready clients will understand this
3178 		 */
3179 		if (strcmp(cmd, "EPSV") != 0)
3180 			reply(501, "Network protocol mismatch"); /*XXX*/
3181 		else
3182 			epsv_protounsupp("Network protocol mismatch");
3183 
3184 		return;
3185 	}
3186 
3187 	if (pdata >= 0)
3188 		close(pdata);
3189 	pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
3190 	if (pdata < 0) {
3191 		perror_reply(425, "Can't open passive connection");
3192 		return;
3193 	}
3194 	pasv_addr = ctrl_addr;
3195 	if (bind_pasv_addr() < 0)
3196 		goto pasv_error;
3197 	len = pasv_addr.su_len;
3198 	if (getsockname(pdata, (struct sockaddr *) &pasv_addr.si_su, &len) < 0)
3199 		goto pasv_error;
3200 	pasv_addr.su_len = len;
3201 	if (listen(pdata, 1) < 0)
3202 		goto pasv_error;
3203 	p = (char *) &pasv_addr.su_port;
3204 
3205 #define UC(b) (((int) b) & 0xff)
3206 
3207 	if (strcmp(cmd, "LPSV") == 0) {
3208 		struct sockinet *advert;
3209 
3210 		if (curclass.advertise.su_len != 0)
3211 			advert = &curclass.advertise;
3212 		else
3213 			advert = &pasv_addr;
3214 		switch (advert->su_family) {
3215 		case AF_INET:
3216 			a = (char *) &advert->su_addr;
3217 			reply(228,
3218     "Entering Long Passive Mode (%d,%d,%d,%d,%d,%d,%d,%d,%d)",
3219 				4, 4, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
3220 				2, UC(p[0]), UC(p[1]));
3221 			return;
3222 #ifdef INET6
3223 		case AF_INET6:
3224 			a = (char *) &advert->su_6addr;
3225 			reply(228,
3226     "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)",
3227 				6, 16,
3228 				UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
3229 				UC(a[4]), UC(a[5]), UC(a[6]), UC(a[7]),
3230 				UC(a[8]), UC(a[9]), UC(a[10]), UC(a[11]),
3231 				UC(a[12]), UC(a[13]), UC(a[14]), UC(a[15]),
3232 				2, UC(p[0]), UC(p[1]));
3233 			return;
3234 #endif
3235 		}
3236 #undef UC
3237 	} else if (strcmp(cmd, "EPSV") == 0) {
3238 		switch (pasv_addr.su_family) {
3239 		case AF_INET:
3240 #ifdef INET6
3241 		case AF_INET6:
3242 #endif
3243 			reply(229, "Entering Extended Passive Mode (|||%d|)",
3244 			    ntohs(pasv_addr.su_port));
3245 			return;
3246 		}
3247 	} else {
3248 		/* more proper error code? */
3249 	}
3250 
3251  pasv_error:
3252 	(void) close(pdata);
3253 	pdata = -1;
3254 	perror_reply(425, "Can't open passive connection");
3255 	return;
3256 }
3257 
3258 int
3259 extended_port(const char *arg)
3260 {
3261 	char *tmp = NULL;
3262 	char *result[3];
3263 	char *p, *q;
3264 	char delim;
3265 	struct addrinfo hints;
3266 	struct addrinfo *res = NULL;
3267 	int i;
3268 	unsigned long proto;
3269 
3270 	tmp = ftpd_strdup(arg);
3271 	p = tmp;
3272 	delim = p[0];
3273 	p++;
3274 	memset(result, 0, sizeof(result));
3275 	for (i = 0; i < 3; i++) {
3276 		q = strchr(p, delim);
3277 		if (!q || *q != delim)
3278 			goto parsefail;
3279 		*q++ = '\0';
3280 		result[i] = p;
3281 		p = q;
3282 	}
3283 
3284 			/* some more sanity checks */
3285 	errno = 0;
3286 	p = NULL;
3287 	(void)strtoul(result[2], &p, 10);
3288 	if (errno || !*result[2] || *p)
3289 		goto parsefail;
3290 	errno = 0;
3291 	p = NULL;
3292 	proto = strtoul(result[0], &p, 10);
3293 	if (errno || !*result[0] || *p)
3294 		goto protounsupp;
3295 
3296 	memset(&hints, 0, sizeof(hints));
3297 	hints.ai_family = epsvproto2af((int)proto);
3298 	if (hints.ai_family < 0)
3299 		goto protounsupp;
3300 	hints.ai_socktype = SOCK_STREAM;
3301 	hints.ai_flags = AI_NUMERICHOST;
3302 	if (getaddrinfo(result[1], result[2], &hints, &res))
3303 		goto parsefail;
3304 	if (res->ai_next)
3305 		goto parsefail;
3306 	if (sizeof(data_dest) < res->ai_addrlen)
3307 		goto parsefail;
3308 	memcpy(&data_dest.si_su, res->ai_addr, res->ai_addrlen);
3309 	data_dest.su_len = res->ai_addrlen;
3310 #ifdef INET6
3311 	if (his_addr.su_family == AF_INET6 &&
3312 	    data_dest.su_family == AF_INET6) {
3313 			/* XXX: more sanity checks! */
3314 		data_dest.su_scope_id = his_addr.su_scope_id;
3315 	}
3316 #endif
3317 
3318 	if (tmp != NULL)
3319 		free(tmp);
3320 	if (res)
3321 		freeaddrinfo(res);
3322 	return 0;
3323 
3324  parsefail:
3325 	reply(500, "Invalid argument, rejected.");
3326 	usedefault = 1;
3327 	if (tmp != NULL)
3328 		free(tmp);
3329 	if (res)
3330 		freeaddrinfo(res);
3331 	return -1;
3332 
3333  protounsupp:
3334 	epsv_protounsupp("Protocol not supported");
3335 	usedefault = 1;
3336 	if (tmp != NULL)
3337 		free(tmp);
3338 	return -1;
3339 }
3340 
3341 /*
3342  * 522 Protocol not supported (proto,...)
3343  * as we assume address family for control and data connections are the same,
3344  * we do not return the list of address families we support - instead, we
3345  * return the address family of the control connection.
3346  */
3347 void
3348 epsv_protounsupp(const char *message)
3349 {
3350 	int proto;
3351 
3352 	proto = af2epsvproto(ctrl_addr.su_family);
3353 	if (proto < 0)
3354 		reply(501, "%s", message);	/* XXX */
3355 	else
3356 		reply(522, "%s, use (%d)", message, proto);
3357 }
3358 
3359 /*
3360  * Generate unique name for file with basename "local".
3361  * The file named "local" is already known to exist.
3362  * Generates failure reply on error.
3363  *
3364  * XXX:	this function should under go changes similar to
3365  *	the mktemp(3)/mkstemp(3) changes.
3366  */
3367 static char *
3368 gunique(const char *local)
3369 {
3370 	static char new[MAXPATHLEN];
3371 	struct stat st;
3372 	char *cp;
3373 	int count;
3374 
3375 	cp = strrchr(local, '/');
3376 	if (cp)
3377 		*cp = '\0';
3378 	if (stat(cp ? local : ".", &st) < 0) {
3379 		perror_reply(553, cp ? local : ".");
3380 		return (NULL);
3381 	}
3382 	if (cp)
3383 		*cp = '/';
3384 	for (count = 1; count < 100; count++) {
3385 		(void)snprintf(new, sizeof(new) - 1, "%s.%d", local, count);
3386 		if (stat(new, &st) < 0)
3387 			return (new);
3388 	}
3389 	reply(452, "Unique file name cannot be created.");
3390 	return (NULL);
3391 }
3392 
3393 /*
3394  * Format and send reply containing system error number.
3395  */
3396 void
3397 perror_reply(int code, const char *string)
3398 {
3399 	int save_errno;
3400 
3401 	save_errno = errno;
3402 	reply(code, "%s: %s.", string, strerror(errno));
3403 	errno = save_errno;
3404 }
3405 
3406 static char *onefile[] = {
3407 	NULL,
3408 	0
3409 };
3410 
3411 void
3412 send_file_list(const char *whichf)
3413 {
3414 	struct stat st;
3415 	DIR *dirp;
3416 	struct dirent *dir;
3417 	FILE *volatile dout;
3418 	char **volatile dirlist;
3419 	char *dirname, *p;
3420 	char *notglob;
3421 	int volatile simple;
3422 	int volatile freeglob;
3423 	glob_t gl;
3424 
3425 	dirp = NULL;
3426 	dout = NULL;
3427 	notglob = NULL;
3428 	simple = 0;
3429 	freeglob = 0;
3430 	urgflag = 0;
3431 
3432 	p = NULL;
3433 	if (strpbrk(whichf, "~{[*?") != NULL) {
3434 		int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE|GLOB_LIMIT;
3435 
3436 		memset(&gl, 0, sizeof(gl));
3437 		freeglob = 1;
3438 		if (glob(whichf, flags, 0, &gl)) {
3439 			reply(450, "Not found");
3440 			goto cleanup_send_file_list;
3441 		} else if (gl.gl_pathc == 0) {
3442 			errno = ENOENT;
3443 			perror_reply(450, whichf);
3444 			goto cleanup_send_file_list;
3445 		}
3446 		dirlist = gl.gl_pathv;
3447 	} else {
3448 		notglob = ftpd_strdup(whichf);
3449 		onefile[0] = notglob;
3450 		dirlist = onefile;
3451 		simple = 1;
3452 	}
3453 					/* XXX: } for vi sm */
3454 
3455 	while ((dirname = *dirlist++) != NULL) {
3456 		int trailingslash = 0;
3457 
3458 		if (stat(dirname, &st) < 0) {
3459 			/*
3460 			 * If user typed "ls -l", etc, and the client
3461 			 * used NLST, do what the user meant.
3462 			 */
3463 			/* XXX: nuke this support? */
3464 			if (dirname[0] == '-' && *dirlist == NULL &&
3465 			    transflag == 0) {
3466 				const char *argv[] = { INTERNAL_LS, "", NULL };
3467 
3468 				argv[1] = dirname;
3469 				retrieve(argv, dirname);
3470 				goto cleanup_send_file_list;
3471 			}
3472 			perror_reply(450, whichf);
3473 			goto cleanup_send_file_list;
3474 		}
3475 
3476 		if (S_ISREG(st.st_mode)) {
3477 			/*
3478 			 * XXXRFC:
3479 			 *	should we follow RFC959 and not work
3480 			 *	for non directories?
3481 			 */
3482 			if (dout == NULL) {
3483 				dout = dataconn("file list", (off_t)-1, "w");
3484 				if (dout == NULL)
3485 					goto cleanup_send_file_list;
3486 				transflag = 1;
3487 			}
3488 			cprintf(dout, "%s%s\n", dirname,
3489 			    type == TYPE_A ? "\r" : "");
3490 			continue;
3491 		} else if (!S_ISDIR(st.st_mode))
3492 			continue;
3493 
3494 		if (dirname[strlen(dirname) - 1] == '/')
3495 			trailingslash++;
3496 
3497 		if ((dirp = opendir(dirname)) == NULL)
3498 			continue;
3499 
3500 		while ((dir = readdir(dirp)) != NULL) {
3501 			char nbuf[MAXPATHLEN];
3502 
3503 			if (urgflag && handleoobcmd())
3504 				goto cleanup_send_file_list;
3505 
3506 			if (ISDOTDIR(dir->d_name) || ISDOTDOTDIR(dir->d_name))
3507 				continue;
3508 
3509 			(void)snprintf(nbuf, sizeof(nbuf), "%s%s%s", dirname,
3510 			    trailingslash ? "" : "/", dir->d_name);
3511 
3512 			/*
3513 			 * We have to do a stat to ensure it's
3514 			 * not a directory or special file.
3515 			 */
3516 			/*
3517 			 * XXXRFC:
3518 			 *	should we follow RFC959 and filter out
3519 			 *	non files ?   lukem - NO!, or not until
3520 			 *	our ftp client uses MLS{T,D} for completion.
3521 			 */
3522 			if (simple || (stat(nbuf, &st) == 0 &&
3523 			    S_ISREG(st.st_mode))) {
3524 				if (dout == NULL) {
3525 					dout = dataconn("file list", (off_t)-1,
3526 						"w");
3527 					if (dout == NULL)
3528 						goto cleanup_send_file_list;
3529 					transflag = 1;
3530 				}
3531 				p = nbuf;
3532 				if (nbuf[0] == '.' && nbuf[1] == '/')
3533 					p = &nbuf[2];
3534 				cprintf(dout, "%s%s\n", p,
3535 				    type == TYPE_A ? "\r" : "");
3536 			}
3537 		}
3538 		(void) closedir(dirp);
3539 	}
3540 
3541 	if (dout == NULL)
3542 		reply(450, "No files found.");
3543 	else if (ferror(dout) != 0)
3544 		perror_reply(451, "Data connection");
3545 	else
3546 		reply(226, "Transfer complete.");
3547 
3548  cleanup_send_file_list:
3549 	closedataconn(dout);
3550 	transflag = 0;
3551 	urgflag = 0;
3552 	total_xfers++;
3553 	total_xfers_out++;
3554 	if (notglob)
3555 		free(notglob);
3556 	if (freeglob)
3557 		globfree(&gl);
3558 }
3559 
3560 char *
3561 conffilename(const char *s)
3562 {
3563 	static char filename[MAXPATHLEN];
3564 
3565 	if (*s == '/')
3566 		strlcpy(filename, s, sizeof(filename));
3567 	else
3568 		(void)snprintf(filename, sizeof(filename), "%s/%s", confdir ,s);
3569 	return (filename);
3570 }
3571 
3572 /*
3573  * logxfer --
3574  *	if logging > 1, then based on the arguments, syslog a message:
3575  *	 if bytes != -1		"<command> <file1> = <bytes> bytes"
3576  *	 else if file2 != NULL	"<command> <file1> <file2>"
3577  *	 else			"<command> <file1>"
3578  *	if elapsed != NULL, append "in xxx.yyy seconds"
3579  *	if error != NULL, append ": " + error
3580  *
3581  *	if doxferlog != 0, bytes != -1, and command is "get", "put",
3582  *	or "append", syslog and/or write a wu-ftpd style xferlog entry
3583  */
3584 void
3585 logxfer(const char *command, off_t bytes, const char *file1, const char *file2,
3586     const struct timeval *elapsed, const char *error)
3587 {
3588 	char		 buf[MAXPATHLEN * 2 + 100];
3589 	char		 realfile1[MAXPATHLEN], realfile2[MAXPATHLEN];
3590 	const char	*r1, *r2;
3591 	char		 direction;
3592 	size_t		 len;
3593 	time_t		 now;
3594 
3595 	if (logging <=1 && !doxferlog)
3596 		return;
3597 
3598 	r1 = r2 = NULL;
3599 	if ((r1 = realpath(file1, realfile1)) == NULL)
3600 		r1 = file1;
3601 	if (file2 != NULL)
3602 		if ((r2 = realpath(file2, realfile2)) == NULL)
3603 			r2 = file2;
3604 
3605 		/*
3606 		 * syslog command
3607 		 */
3608 	if (logging > 1) {
3609 		len = snprintf(buf, sizeof(buf), "%s %s", command, r1);
3610 		if (bytes != (off_t)-1)
3611 			len += snprintf(buf + len, sizeof(buf) - len,
3612 			    " = " LLF " byte%s", (LLT) bytes, PLURAL(bytes));
3613 		else if (r2 != NULL)
3614 			len += snprintf(buf + len, sizeof(buf) - len,
3615 			    " %s", r2);
3616 		if (elapsed != NULL)
3617 			len += snprintf(buf + len, sizeof(buf) - len,
3618 			    " in " LLF ".%.03ld seconds",
3619 			    (LLT)elapsed->tv_sec,
3620 			    (long)(elapsed->tv_usec / 1000));
3621 		if (error != NULL)
3622 			len += snprintf(buf + len, sizeof(buf) - len,
3623 			    ": %s", error);
3624 		syslog(LOG_INFO, "%s", buf);
3625 	}
3626 
3627 		/*
3628 		 * syslog wu-ftpd style log entry, prefixed with "xferlog: "
3629 		 */
3630 	if (!doxferlog || bytes == -1)
3631 		return;
3632 
3633 	if (strcmp(command, "get") == 0)
3634 		direction = 'o';
3635 	else if (strcmp(command, "put") == 0 || strcmp(command, "append") == 0)
3636 		direction = 'i';
3637 	else
3638 		return;
3639 
3640 	time(&now);
3641 	len = snprintf(buf, sizeof(buf),
3642 	    "%.24s " LLF " %s " LLF " %s %c %s %c %c %s FTP 0 * %c\n",
3643 
3644 /*
3645  * XXX: wu-ftpd puts ' (send)' or ' (recv)' in the syslog message, and removes
3646  *	the full date.  This may be problematic for accurate log parsing,
3647  *	given that syslog messages don't contain the full date.
3648  */
3649 	    ctime(&now),
3650 	    (LLT)
3651 	    (elapsed == NULL ? 0 : elapsed->tv_sec + (elapsed->tv_usec > 0)),
3652 	    remotehost,
3653 	    (LLT) bytes,
3654 	    r1,
3655 	    type == TYPE_A ? 'a' : 'b',
3656 	    "_",		/* XXX: take conversions into account? */
3657 	    direction,
3658 
3659 	    curclass.type == CLASS_GUEST ?  'a' :
3660 	    curclass.type == CLASS_CHROOT ? 'g' :
3661 	    curclass.type == CLASS_REAL ?   'r' : '?',
3662 
3663 	    curclass.type == CLASS_GUEST ? pw->pw_passwd : pw->pw_name,
3664 	    error != NULL ? 'i' : 'c'
3665 	    );
3666 
3667 	if ((doxferlog & 2) && xferlogfd != -1)
3668 		write(xferlogfd, buf, len);
3669 	if ((doxferlog & 1)) {
3670 		buf[len-1] = '\n';	/* strip \n from syslog message */
3671 		syslog(LOG_INFO, "xferlog: %s", buf);
3672 	}
3673 }
3674 
3675 #if !defined(__minix)
3676 /*
3677  * Log the resource usage.
3678  *
3679  * XXX: more resource usage to logging?
3680  */
3681 void
3682 logrusage(const struct rusage *rusage_before,
3683     const struct rusage *rusage_after)
3684 {
3685 	struct timeval usrtime, systime;
3686 
3687 	if (logging <= 1)
3688 		return;
3689 
3690 	timersub(&rusage_after->ru_utime, &rusage_before->ru_utime, &usrtime);
3691 	timersub(&rusage_after->ru_stime, &rusage_before->ru_stime, &systime);
3692 	syslog(LOG_INFO, LLF ".%.03ldu " LLF ".%.03lds %ld+%ldio %ldpf+%ldw",
3693 	    (LLT)usrtime.tv_sec, (long)(usrtime.tv_usec / 1000),
3694 	    (LLT)systime.tv_sec, (long)(systime.tv_usec / 1000),
3695 	    rusage_after->ru_inblock - rusage_before->ru_inblock,
3696 	    rusage_after->ru_oublock - rusage_before->ru_oublock,
3697 	    rusage_after->ru_majflt - rusage_before->ru_majflt,
3698 	    rusage_after->ru_nswap - rusage_before->ru_nswap);
3699 }
3700 #endif /* !defined(__minix) */
3701 
3702 /*
3703  * Determine if `password' is valid for user given in `pw'.
3704  * Returns 2 if password expired, 1 if otherwise failed, 0 if ok
3705  */
3706 int
3707 checkpassword(const struct passwd *pwent, const char *password)
3708 {
3709 	const char *orig;
3710 	char	*new;
3711 	time_t	 change, expire, now;
3712 
3713 	change = expire = 0;
3714 	if (pwent == NULL)
3715 		return 1;
3716 
3717 	time(&now);
3718 	orig = pwent->pw_passwd;	/* save existing password */
3719 	expire = pwent->pw_expire;
3720 	change = pwent->pw_change;
3721 	if (change == _PASSWORD_CHGNOW)
3722 		change = now;
3723 
3724 	if (orig[0] == '\0')		/* don't allow empty passwords */
3725 		return 1;
3726 
3727 	new = crypt(password, orig);	/* encrypt given password */
3728 	if (strcmp(new, orig) != 0)	/* compare */
3729 		return 1;
3730 
3731 	if ((expire && now >= expire) || (change && now >= change))
3732 		return 2;		/* check if expired */
3733 
3734 	return 0;			/* OK! */
3735 }
3736 
3737 char *
3738 ftpd_strdup(const char *s)
3739 {
3740 	char *new = strdup(s);
3741 
3742 	if (new == NULL)
3743 		fatal("Local resource failure: malloc");
3744 		/* NOTREACHED */
3745 	return (new);
3746 }
3747 
3748 /*
3749  * As per fprintf(), but increment total_bytes and total_bytes_out,
3750  * by the appropriate amount.
3751  */
3752 void
3753 cprintf(FILE *fd, const char *fmt, ...)
3754 {
3755 	off_t b;
3756 	va_list ap;
3757 
3758 	va_start(ap, fmt);
3759 	b = vfprintf(fd, fmt, ap);
3760 	va_end(ap);
3761 	total_bytes += b;
3762 	total_bytes_out += b;
3763 }
3764 
3765 #ifdef USE_PAM
3766 /*
3767  * the following code is stolen from imap-uw PAM authentication module and
3768  * login.c
3769  */
3770 typedef struct {
3771 	const char *uname;	/* user name */
3772 	int	    triedonce;	/* if non-zero, tried before */
3773 } ftpd_cred_t;
3774 
3775 static int
3776 auth_conv(int num_msg, const struct pam_message **msg,
3777     struct pam_response **resp, void *appdata)
3778 {
3779 	int i, ret;
3780 	size_t n;
3781 	ftpd_cred_t *cred = (ftpd_cred_t *) appdata;
3782 	struct pam_response *myreply;
3783 	char pbuf[FTP_BUFLEN];
3784 
3785 	if (num_msg <= 0 || num_msg > PAM_MAX_NUM_MSG)
3786 		return (PAM_CONV_ERR);
3787 	myreply = calloc(num_msg, sizeof *myreply);
3788 	if (myreply == NULL)
3789 		return PAM_BUF_ERR;
3790 
3791 	for (i = 0; i < num_msg; i++) {
3792 		myreply[i].resp_retcode = 0;
3793 		myreply[i].resp = NULL;
3794 		switch (msg[i]->msg_style) {
3795 		case PAM_PROMPT_ECHO_ON:	/* user */
3796 			myreply[i].resp = ftpd_strdup(cred->uname);
3797 			/* PAM frees resp. */
3798 			break;
3799 		case PAM_PROMPT_ECHO_OFF:	/* authtok (password) */
3800 				/*
3801 				 * Only send a single 331 reply and
3802 				 * then expect a PASS.
3803 				 */
3804 			if (cred->triedonce) {
3805 				syslog(LOG_ERR,
3806 			"auth_conv: already performed PAM_PROMPT_ECHO_OFF");
3807 				goto fail;
3808 			}
3809 			cred->triedonce++;
3810 			if (msg[i]->msg[0] == '\0') {
3811 				(void)strlcpy(pbuf, "password", sizeof(pbuf));
3812 			} else {
3813 					/* Uncapitalize msg */
3814 				(void)strlcpy(pbuf, msg[i]->msg, sizeof(pbuf));
3815 				if (isupper((unsigned char)pbuf[0]))
3816 					pbuf[0] = tolower(
3817 					    (unsigned char)pbuf[0]);
3818 					/* Remove trailing ':' and whitespace */
3819 				n = strlen(pbuf);
3820 				while (n-- > 0) {
3821 					if (isspace((unsigned char)pbuf[n]) ||
3822 					    pbuf[n] == ':')
3823 						pbuf[n] = '\0';
3824 					else
3825 						break;
3826 				}
3827 			}
3828 				/* Send reply, wait for a response. */
3829 			reply(331, "User %s accepted, provide %s.",
3830 			    cred->uname, pbuf);
3831 			(void) alarm(curclass.timeout);
3832 			ret = get_line(pbuf, sizeof(pbuf)-1, stdin);
3833 			(void) alarm(0);
3834 			if (ret == -1) {
3835 				reply(221, "You could at least say goodbye.");
3836 				dologout(0);
3837 			} else if (ret == -2) {
3838 			    /* XXX: should we do this reply(-530, ..) ? */
3839 				reply(-530, "Command too long.");
3840 				goto fail;
3841 			}
3842 				/* Ensure it is PASS */
3843 			if (strncasecmp(pbuf, "PASS ", 5) != 0) {
3844 				syslog(LOG_ERR,
3845 				    "auth_conv: unexpected reply '%.4s'", pbuf);
3846 				/* XXX: should we do this reply(-530, ..) ? */
3847 				reply(-530, "Unexpected reply '%.4s'.", pbuf);
3848 				goto fail;
3849 			}
3850 				/* Strip CRLF from "PASS" reply */
3851 			n = strlen(pbuf);
3852 			while (--n >= 5 &&
3853 			    (pbuf[n] == '\r' || pbuf[n] == '\n'))
3854 			    pbuf[n] = '\0';
3855 				/* Copy password into reply */
3856 			myreply[i].resp = ftpd_strdup(pbuf+5);
3857 				/* PAM frees resp. */
3858 			break;
3859 		case PAM_TEXT_INFO:
3860 		case PAM_ERROR_MSG:
3861 			break;
3862 		default:			/* unknown message style */
3863 			goto fail;
3864 		}
3865 	}
3866 
3867 	*resp = myreply;
3868 	return PAM_SUCCESS;
3869 
3870  fail:
3871 	free(myreply);
3872 	*resp = NULL;
3873 	return PAM_CONV_ERR;
3874 }
3875 
3876 /*
3877  * Attempt to authenticate the user using PAM.  Returns 0 if the user is
3878  * authenticated, or 1 if not authenticated.  If some sort of PAM system
3879  * error occurs (e.g., the "/etc/pam.conf" file is missing) then this
3880  * function returns -1.  This can be used as an indication that we should
3881  * fall back to a different authentication mechanism.
3882  * pw maybe be updated to a new user if PAM_USER changes from curname.
3883  */
3884 static int
3885 auth_pam(void)
3886 {
3887 	const char *tmpl_user;
3888 	const void *item;
3889 	int rval;
3890 	int e;
3891 	ftpd_cred_t auth_cred = { curname, 0 };
3892 	struct pam_conv conv = { &auth_conv, &auth_cred };
3893 
3894 	e = pam_start("ftpd", curname, &conv, &pamh);
3895 	if (e != PAM_SUCCESS) {
3896 		/*
3897 		 * In OpenPAM, it's OK to pass NULL to pam_strerror()
3898 		 * if context creation has failed in the first place.
3899 		 */
3900 		syslog(LOG_ERR, "pam_start: %s", pam_strerror(NULL, e));
3901 		return -1;
3902 	}
3903 
3904 	e = pam_set_item(pamh, PAM_RHOST, remotehost);
3905 	if (e != PAM_SUCCESS) {
3906 		syslog(LOG_ERR, "pam_set_item(PAM_RHOST): %s",
3907 			pam_strerror(pamh, e));
3908 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
3909 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
3910 		}
3911 		pamh = NULL;
3912 		return -1;
3913 	}
3914 
3915 	e = pam_set_item(pamh, PAM_SOCKADDR, &his_addr);
3916 	if (e != PAM_SUCCESS) {
3917 		syslog(LOG_ERR, "pam_set_item(PAM_SOCKADDR): %s",
3918 			pam_strerror(pamh, e));
3919 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
3920 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
3921 		}
3922 		pamh = NULL;
3923 		return -1;
3924 	}
3925 
3926 	e = pam_authenticate(pamh, 0);
3927 	if (ftpd_debug)
3928 		syslog(LOG_DEBUG, "pam_authenticate: user '%s' returned %d",
3929 		    curname, e);
3930 	switch (e) {
3931 	case PAM_SUCCESS:
3932 		/*
3933 		 * With PAM we support the concept of a "template"
3934 		 * user.  The user enters a login name which is
3935 		 * authenticated by PAM, usually via a remote service
3936 		 * such as RADIUS or TACACS+.  If authentication
3937 		 * succeeds, a different but related "template" name
3938 		 * is used for setting the credentials, shell, and
3939 		 * home directory.  The name the user enters need only
3940 		 * exist on the remote authentication server, but the
3941 		 * template name must be present in the local password
3942 		 * database.
3943 		 *
3944 		 * This is supported by two various mechanisms in the
3945 		 * individual modules.  However, from the application's
3946 		 * point of view, the template user is always passed
3947 		 * back as a changed value of the PAM_USER item.
3948 		 */
3949 		if ((e = pam_get_item(pamh, PAM_USER, &item)) ==
3950 		    PAM_SUCCESS) {
3951 			tmpl_user = (const char *) item;
3952 			if (pw == NULL
3953 			    || strcmp(pw->pw_name, tmpl_user) != 0) {
3954 				pw = sgetpwnam(tmpl_user);
3955 				if (ftpd_debug)
3956 					syslog(LOG_DEBUG,
3957 					    "auth_pam: PAM changed "
3958 					    "user from '%s' to '%s'",
3959 					    curname, pw->pw_name);
3960 				(void)strlcpy(curname, pw->pw_name,
3961 				    curname_len);
3962 			}
3963 		} else
3964 			syslog(LOG_ERR, "Couldn't get PAM_USER: %s",
3965 			    pam_strerror(pamh, e));
3966 		rval = 0;
3967 		break;
3968 
3969 	case PAM_AUTH_ERR:
3970 	case PAM_USER_UNKNOWN:
3971 	case PAM_MAXTRIES:
3972 		rval = 1;
3973 		break;
3974 
3975 	default:
3976 		syslog(LOG_ERR, "pam_authenticate: %s", pam_strerror(pamh, e));
3977 		rval = -1;
3978 		break;
3979 	}
3980 
3981 	if (rval == 0) {
3982 		e = pam_acct_mgmt(pamh, 0);
3983 		if (e != PAM_SUCCESS) {
3984 			syslog(LOG_ERR, "pam_acct_mgmt: %s",
3985 						pam_strerror(pamh, e));
3986 			rval = 1;
3987 		}
3988 	}
3989 
3990 	if (rval != 0) {
3991 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
3992 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
3993 		}
3994 		pamh = NULL;
3995 	}
3996 	return rval;
3997 }
3998 
3999 #endif /* USE_PAM */
4000