xref: /minix/libexec/ftpd/ftpd.c (revision 5bded7c0)
1 /*	$NetBSD: ftpd.c,v 1.202 2015/08/10 07:32:49 shm 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 1.202 2015/08/10 07:32:49 shm Exp $");
101 #endif
102 #endif /* not lint */
103 
104 /*
105  * FTP server.
106  */
107 #include <sys/param.h>
108 #include <sys/stat.h>
109 #include <sys/ioctl.h>
110 #include <sys/socket.h>
111 #include <sys/wait.h>
112 #include <sys/mman.h>
113 #include <sys/resource.h>
114 
115 #include <netinet/in.h>
116 #include <netinet/in_systm.h>
117 #include <netinet/ip.h>
118 
119 #define	FTP_NAMES
120 #include <arpa/ftp.h>
121 #include <arpa/inet.h>
122 #include <arpa/telnet.h>
123 
124 #include <ctype.h>
125 #include <dirent.h>
126 #include <err.h>
127 #include <errno.h>
128 #include <fcntl.h>
129 #include <fnmatch.h>
130 #include <glob.h>
131 #include <grp.h>
132 #include <limits.h>
133 #include <netdb.h>
134 #include <pwd.h>
135 #include <poll.h>
136 #include <signal.h>
137 #include <stdarg.h>
138 #include <stdio.h>
139 #include <stdlib.h>
140 #include <string.h>
141 #include <syslog.h>
142 #include <time.h>
143 #include <tzfile.h>
144 #include <unistd.h>
145 #include <util.h>
146 #ifdef SUPPORT_UTMP
147 #include <utmp.h>
148 #endif
149 #ifdef SUPPORT_UTMPX
150 #include <utmpx.h>
151 #endif
152 #ifdef SKEY
153 #include <skey.h>
154 #endif
155 #ifdef KERBEROS5
156 #include <com_err.h>
157 #include <krb5/krb5.h>
158 #endif
159 
160 #ifdef	LOGIN_CAP
161 #include <login_cap.h>
162 #endif
163 
164 #ifdef USE_PAM
165 #include <security/pam_appl.h>
166 #endif
167 
168 #include "pfilter.h"
169 
170 #define	GLOBAL
171 #include "extern.h"
172 #include "pathnames.h"
173 #include "version.h"
174 
175 static sig_atomic_t	transflag;
176 static sig_atomic_t	urgflag;
177 
178 int	data;
179 int	Dflag;
180 int	sflag;
181 int	stru;			/* avoid C keyword */
182 int	mode;
183 int	dataport;		/* use specific data port */
184 int	dopidfile;		/* maintain pid file */
185 int	doutmp;			/* update utmp file */
186 int	dowtmp;			/* update wtmp file */
187 int	doxferlog;		/* syslog/write wu-ftpd style xferlog entries */
188 int	xferlogfd;		/* fd to write wu-ftpd xferlog entries to */
189 int	getnameopts;		/* flags for use with getname() */
190 int	dropprivs;		/* if privileges should or have been dropped */
191 int	mapped;			/* IPv4 connection on AF_INET6 socket */
192 off_t	file_size;
193 off_t	byte_count;
194 static char ttyline[20];
195 
196 #ifdef USE_PAM
197 static int	auth_pam(void);
198 pam_handle_t	*pamh = NULL;
199 #endif
200 
201 #ifdef SUPPORT_UTMP
202 static struct utmp utmp;	/* for utmp */
203 #endif
204 #ifdef SUPPORT_UTMPX
205 static struct utmpx utmpx;	/* for utmpx */
206 #endif
207 
208 static const char *anondir = NULL;
209 static const char *confdir = _DEFAULT_CONFDIR;
210 
211 static char	*curname;		/* current USER name */
212 static size_t	curname_len;		/* length of curname (include NUL) */
213 
214 #if defined(KERBEROS) || defined(KERBEROS5)
215 int	has_ccache = 0;
216 int	notickets = 1;
217 char	*krbtkfile_env = NULL;
218 char	*tty = ttyline;
219 int	login_krb5_forwardable_tgt = 0;
220 #endif
221 
222 int epsvall = 0;
223 
224 /*
225  * Timeout intervals for retrying connections
226  * to hosts that don't accept PORT cmds.  This
227  * is a kludge, but given the problems with TCP...
228  */
229 #define	SWAITMAX	90	/* wait at most 90 seconds */
230 #define	SWAITINT	5	/* interval between retries */
231 
232 int	swaitmax = SWAITMAX;
233 int	swaitint = SWAITINT;
234 
235 enum send_status {
236 	SS_SUCCESS,
237 	SS_ABORTED,			/* transfer aborted */
238 	SS_NO_TRANSFER,			/* no transfer made yet */
239 	SS_FILE_ERROR,			/* file read error */
240 	SS_DATA_ERROR			/* data send error */
241 };
242 
243 static int	 bind_pasv_addr(void);
244 static int	 checkuser(const char *, const char *, int, int, char **);
245 static int	 checkaccess(const char *);
246 static int	 checkpassword(const struct passwd *, const char *);
247 static void	 do_pass(int, int, const char *);
248 static void	 end_login(void);
249 static FILE	*getdatasock(const char *);
250 static char	*gunique(const char *);
251 static void	 login_utmp(const char *, const char *, const char *,
252 		     struct sockinet *);
253 static void	 logremotehost(struct sockinet *);
254 __dead static void	 lostconn(int);
255 __dead static void	 toolong(int);
256 __dead static void	 sigquit(int);
257 static void	 sigurg(int);
258 static int	 handleoobcmd(void);
259 static int	 receive_data(FILE *, FILE *);
260 static int	 send_data(FILE *, FILE *, const struct stat *, int);
261 static struct passwd *sgetpwnam(const char *);
262 static int	 write_data(int, char *, size_t, off_t *, struct timeval *,
263 		     int);
264 static enum send_status
265 		 send_data_with_read(int, int, const struct stat *, int);
266 #if !defined(__minix)
267 static enum send_status
268 		 send_data_with_mmap(int, int, const struct stat *, int);
269 #endif /* !defined(__minix) */
270 static void	 logrusage(const struct rusage *, const struct rusage *);
271 static void	 logout_utmp(void);
272 
273 int	main(int, char *[]);
274 
275 #if defined(KERBEROS)
276 int	klogin(struct passwd *, char *, char *, char *);
277 void	kdestroy(void);
278 #endif
279 #if defined(KERBEROS5)
280 int	k5login(struct passwd *, char *, char *, char *);
281 void	k5destroy(void);
282 #endif
283 
284 int
main(int argc,char * argv[])285 main(int argc, char *argv[])
286 {
287 	int		ch, on = 1, tos, keepalive;
288 	socklen_t	addrlen;
289 #ifdef KERBEROS5
290 	krb5_error_code	kerror;
291 #endif
292 	char		*p;
293 	const char	*xferlogname = NULL;
294 	long		l;
295 	struct sigaction sa;
296 	sa_family_t	af = AF_UNSPEC;
297 
298 	connections = 1;
299 	ftpd_debug = 0;
300 	logging = 0;
301 	pdata = -1;
302 	Dflag = 0;
303 	sflag = 0;
304 	dataport = 0;
305 	dopidfile = 1;		/* default: DO use a pid file to count users */
306 	doutmp = 0;		/* default: Do NOT log to utmp */
307 	dowtmp = 1;		/* default: DO log to wtmp */
308 	doxferlog = 0;		/* default: Do NOT syslog xferlog */
309 	xferlogfd = -1;		/* default: Do NOT write xferlog file */
310 	getnameopts = 0;	/* default: xlate addrs to name */
311 	dropprivs = 0;
312 	mapped = 0;
313 	usedefault = 1;
314 	emailaddr = NULL;
315 	hostname[0] = '\0';
316 	homedir[0] = '\0';
317 	gidcount = 0;
318 	is_oob = 0;
319 	version = FTPD_VERSION;
320 
321 	/*
322 	 * LOG_NDELAY sets up the logging connection immediately,
323 	 * necessary for anonymous ftp's that chroot and can't do it later.
324 	 */
325 	openlog("ftpd", LOG_PID | LOG_NDELAY, LOG_FTP);
326 
327 	while ((ch = getopt(argc, argv,
328 	    "46a:c:C:Dde:h:HlL:nP:qQrst:T:uUvV:wWX")) != -1) {
329 		switch (ch) {
330 		case '4':
331 			af = AF_INET;
332 			break;
333 
334 		case '6':
335 			af = AF_INET6;
336 			break;
337 
338 		case 'a':
339 			anondir = optarg;
340 			break;
341 
342 		case 'c':
343 			confdir = optarg;
344 			break;
345 
346 		case 'C':
347 			if ((p = strchr(optarg, '@')) != NULL) {
348 				*p++ = '\0';
349 				strlcpy(remotehost, p, MAXHOSTNAMELEN + 1);
350 				if (inet_pton(AF_INET, p,
351 				    &his_addr.su_addr) == 1) {
352 					his_addr.su_family = AF_INET;
353 					his_addr.su_len =
354 					    sizeof(his_addr.si_su.su_sin);
355 #ifdef INET6
356 				} else if (inet_pton(AF_INET6, p,
357 				    &his_addr.su_6addr) == 1) {
358 					his_addr.su_family = AF_INET6;
359 					his_addr.su_len =
360 					    sizeof(his_addr.si_su.su_sin6);
361 #endif
362 				} else
363 					his_addr.su_family = AF_UNSPEC;
364 			}
365 			pw = sgetpwnam(optarg);
366 			exit(checkaccess(optarg) ? 0 : 1);
367 			/* NOTREACHED */
368 
369 		case 'D':
370 			Dflag = 1;
371 			break;
372 
373 		case 'd':
374 		case 'v':		/* deprecated */
375 			ftpd_debug = 1;
376 			break;
377 
378 		case 'e':
379 			emailaddr = optarg;
380 			break;
381 
382 		case 'h':
383 			strlcpy(hostname, optarg, sizeof(hostname));
384 			break;
385 
386 		case 'H':
387 			if (gethostname(hostname, sizeof(hostname)) == -1)
388 				hostname[0] = '\0';
389 			hostname[sizeof(hostname) - 1] = '\0';
390 			break;
391 
392 		case 'l':
393 			logging++;	/* > 1 == extra logging */
394 			break;
395 
396 		case 'L':
397 			xferlogname = optarg;
398 			break;
399 
400 		case 'n':
401 			getnameopts = NI_NUMERICHOST;
402 			break;
403 
404 		case 'P':
405 			errno = 0;
406 			p = NULL;
407 			l = strtol(optarg, &p, 10);
408 			if (errno || *optarg == '\0' || *p != '\0' ||
409 			    l < IPPORT_RESERVED ||
410 			    l > IPPORT_ANONMAX) {
411 				syslog(LOG_WARNING, "Invalid dataport %s",
412 				    optarg);
413 				dataport = 0;
414 			}
415 			dataport = (int)l;
416 			break;
417 
418 		case 'q':
419 			dopidfile = 1;
420 			break;
421 
422 		case 'Q':
423 			dopidfile = 0;
424 			break;
425 
426 		case 'r':
427 			dropprivs = 1;
428 			break;
429 
430 		case 's':
431 			sflag = 1;
432 			break;
433 
434 		case 't':
435 		case 'T':
436 			syslog(LOG_WARNING,
437 			    "-%c has been deprecated in favour of ftpd.conf",
438 			    ch);
439 			break;
440 
441 		case 'u':
442 			doutmp = 1;
443 			break;
444 
445 		case 'U':
446 			doutmp = 0;
447 			break;
448 
449 		case 'V':
450 			if (EMPTYSTR(optarg) || strcmp(optarg, "-") == 0)
451 				version = NULL;
452 			else
453 				version = ftpd_strdup(optarg);
454 			break;
455 
456 		case 'w':
457 			dowtmp = 1;
458 			break;
459 
460 		case 'W':
461 			dowtmp = 0;
462 			break;
463 
464 		case 'X':
465 			doxferlog |= 1;
466 			break;
467 
468 		default:
469 			if (optopt == 'a' || optopt == 'C')
470 				exit(1);
471 			syslog(LOG_WARNING, "unknown flag -%c ignored", optopt);
472 			break;
473 		}
474 	}
475 	if (EMPTYSTR(confdir))
476 		confdir = _DEFAULT_CONFDIR;
477 
478 	pfilter_open();
479 
480 	if (dowtmp) {
481 #ifdef SUPPORT_UTMPX
482 		ftpd_initwtmpx();
483 #endif
484 #ifdef SUPPORT_UTMP
485 		ftpd_initwtmp();
486 #endif
487 	}
488 	errno = 0;
489 #if !defined(__minix)
490 	l = sysconf(_SC_LOGIN_NAME_MAX);
491 	if (l == -1 && errno != 0) {
492 		syslog(LOG_ERR, "sysconf _SC_LOGIN_NAME_MAX: %m");
493 		exit(1);
494 	} else if (l <= 0) {
495 		syslog(LOG_WARNING, "using conservative LOGIN_NAME_MAX value");
496 		curname_len = _POSIX_LOGIN_NAME_MAX;
497 	} else
498 		curname_len = (size_t)l;
499 #else
500 	curname_len = _POSIX_LOGIN_NAME_MAX;
501 #endif /* !defined(__minix) */
502 	curname = malloc(curname_len);
503 	if (curname == NULL) {
504 		syslog(LOG_ERR, "malloc: %m");
505 		exit(1);
506 	}
507 	curname[0] = '\0';
508 
509 	if (Dflag) {
510 		int error, fd, i, n, *socks;
511 		struct pollfd *fds;
512 		struct addrinfo hints, *res, *res0;
513 
514 		if (daemon(1, 0) == -1) {
515 			syslog(LOG_ERR, "failed to daemonize: %m");
516 			exit(1);
517 		}
518 		(void)memset(&sa, 0, sizeof(sa));
519 		sa.sa_handler = SIG_IGN;
520 		sa.sa_flags = SA_NOCLDWAIT;
521 		sigemptyset(&sa.sa_mask);
522 		(void)sigaction(SIGCHLD, &sa, NULL);
523 
524 		(void)memset(&hints, 0, sizeof(hints));
525 		hints.ai_flags = AI_PASSIVE;
526 		hints.ai_family = af;
527 		hints.ai_socktype = SOCK_STREAM;
528 		error = getaddrinfo(NULL, "ftp", &hints, &res0);
529 		if (error) {
530 			syslog(LOG_ERR, "getaddrinfo: %s", gai_strerror(error));
531 			exit(1);
532 		}
533 
534 		for (n = 0, res = res0; res != NULL; res = res->ai_next)
535 			n++;
536 		if (n == 0) {
537 			syslog(LOG_ERR, "no addresses available");
538 			exit(1);
539 		}
540 		socks = malloc(n * sizeof(int));
541 		fds = malloc(n * sizeof(struct pollfd));
542 		if (socks == NULL || fds == NULL) {
543 			syslog(LOG_ERR, "malloc: %m");
544 			exit(1);
545 		}
546 
547 		for (n = 0, res = res0; res != NULL; res = res->ai_next) {
548 			socks[n] = socket(res->ai_family, res->ai_socktype,
549 			    res->ai_protocol);
550 			if (socks[n] == -1)
551 				continue;
552 			(void)setsockopt(socks[n], SOL_SOCKET, SO_REUSEADDR,
553 			    &on, sizeof(on));
554 			if (bind(socks[n], res->ai_addr, res->ai_addrlen)
555 			    == -1) {
556 				(void)close(socks[n]);
557 				continue;
558 			}
559 			if (listen(socks[n], 12) == -1) {
560 				(void)close(socks[n]);
561 				continue;
562 			}
563 
564 			fds[n].fd = socks[n];
565 			fds[n].events = POLLIN;
566 			n++;
567 		}
568 		if (n == 0) {
569 			syslog(LOG_ERR, "%m");
570 			exit(1);
571 		}
572 		freeaddrinfo(res0);
573 
574 		if (pidfile(NULL) == -1)
575 			syslog(LOG_ERR, "failed to write a pid file: %m");
576 
577 		for (;;) {
578 #ifdef __minix
579 			/*
580 			 * MINIX 3 does not yet support SA_NOCLDWAIT.  Cleaning
581 			 * up zombies this way is not perfect, but at least it
582 			 * prevents accumulation of zombies over time.
583 			 */
584 			while (waitpid(-1, NULL, WNOHANG) > 0)
585 				;
586 #endif /* __minix */
587 			if (poll(fds, n, INFTIM) == -1) {
588 				if (errno == EINTR)
589 					continue;
590 				syslog(LOG_ERR, "poll: %m");
591 				exit(1);
592 			}
593 			for (i = 0; i < n; i++) {
594 				if (fds[i].revents & POLLIN) {
595 					fd = accept(fds[i].fd, NULL, NULL);
596 					if (fd == -1) {
597 						syslog(LOG_ERR, "accept: %m");
598 						continue;
599 					}
600 					switch (fork()) {
601 					case -1:
602 						syslog(LOG_ERR, "fork: %m");
603 						break;
604 					case 0:
605 						goto child;
606 						/* NOTREACHED */
607 					}
608 					(void)close(fd);
609 				}
610 			}
611 		}
612  child:
613 		(void)dup2(fd, STDIN_FILENO);
614 		(void)dup2(fd, STDOUT_FILENO);
615 		(void)dup2(fd, STDERR_FILENO);
616 		for (i = 0; i < n; i++)
617 			(void)close(socks[i]);
618 	}
619 
620 	memset((char *)&his_addr, 0, sizeof(his_addr));
621 	addrlen = sizeof(his_addr.si_su);
622 	if (getpeername(0, (struct sockaddr *)&his_addr.si_su, &addrlen) < 0) {
623 		syslog((errno == ENOTCONN) ? LOG_NOTICE : LOG_ERR,
624 		    "getpeername (%s): %m",argv[0]);
625 		exit(1);
626 	}
627 	his_addr.su_len = addrlen;
628 	memset((char *)&ctrl_addr, 0, sizeof(ctrl_addr));
629 	addrlen = sizeof(ctrl_addr.si_su);
630 	if (getsockname(0, (struct sockaddr *)&ctrl_addr, &addrlen) < 0) {
631 		syslog(LOG_ERR, "getsockname (%s): %m",argv[0]);
632 		exit(1);
633 	}
634 	ctrl_addr.su_len = addrlen;
635 #ifdef INET6
636 	if (his_addr.su_family == AF_INET6
637 	 && IN6_IS_ADDR_V4MAPPED(&his_addr.su_6addr)) {
638 #if 1
639 		/*
640 		 * IPv4 control connection arrived to AF_INET6 socket.
641 		 * I hate to do this, but this is the easiest solution.
642 		 *
643 		 * The assumption is untrue on SIIT environment.
644 		 */
645 		struct sockinet tmp_addr;
646 		const int off = sizeof(struct in6_addr) - sizeof(struct in_addr);
647 
648 		tmp_addr = his_addr;
649 		memset(&his_addr, 0, sizeof(his_addr));
650 		his_addr.su_family = AF_INET;
651 		his_addr.su_len = sizeof(his_addr.si_su.su_sin);
652 		memcpy(&his_addr.su_addr, &tmp_addr.su_6addr.s6_addr[off],
653 		    sizeof(his_addr.su_addr));
654 		his_addr.su_port = tmp_addr.su_port;
655 
656 		tmp_addr = ctrl_addr;
657 		memset(&ctrl_addr, 0, sizeof(ctrl_addr));
658 		ctrl_addr.su_family = AF_INET;
659 		ctrl_addr.su_len = sizeof(ctrl_addr.si_su.su_sin);
660 		memcpy(&ctrl_addr.su_addr, &tmp_addr.su_6addr.s6_addr[off],
661 		    sizeof(ctrl_addr.su_addr));
662 		ctrl_addr.su_port = tmp_addr.su_port;
663 #else
664 		while (fgets(line, sizeof(line), fd) != NULL) {
665 			if ((cp = strchr(line, '\n')) != NULL)
666 				*cp = '\0';
667 			reply(-530, "%s", line);
668 		}
669 		(void) fflush(stdout);
670 		(void) fclose(fd);
671 		reply(530,
672 		    "Connection from IPv4 mapped address is not supported.");
673 		exit(0);
674 #endif
675 
676 		mapped = 1;
677 	} else
678 #endif /* INET6 */
679 		mapped = 0;
680 #ifdef IP_TOS
681 	if (!mapped && his_addr.su_family == AF_INET) {
682 		tos = IPTOS_LOWDELAY;
683 		if (setsockopt(0, IPPROTO_IP, IP_TOS, (char *)&tos,
684 			       sizeof(int)) < 0)
685 			syslog(LOG_WARNING, "setsockopt (IP_TOS): %m");
686 	}
687 #endif
688 	/* if the hostname hasn't been given, attempt to determine it */
689 	if (hostname[0] == '\0') {
690 		if (getnameinfo((struct sockaddr *)&ctrl_addr.si_su,
691 		    ctrl_addr.su_len, hostname, sizeof(hostname), NULL, 0,
692 			getnameopts) != 0)
693 			(void)gethostname(hostname, sizeof(hostname));
694 		hostname[sizeof(hostname) - 1] = '\0';
695 	}
696 
697 	/* set this here so klogin can use it... */
698 	(void)snprintf(ttyline, sizeof(ttyline), "ftp%d", getpid());
699 
700 	(void) freopen(_PATH_DEVNULL, "w", stderr);
701 
702 	memset(&sa, 0, sizeof(sa));
703 	sa.sa_handler = SIG_DFL;
704 	sa.sa_flags = SA_RESTART;
705 	sigemptyset(&sa.sa_mask);
706 	(void) sigaction(SIGCHLD, &sa, NULL);
707 
708 	sa.sa_handler = sigquit;
709 	sa.sa_flags = SA_RESTART;
710 	sigfillset(&sa.sa_mask);	/* block all sigs in these handlers */
711 	(void) sigaction(SIGHUP, &sa, NULL);
712 	(void) sigaction(SIGINT, &sa, NULL);
713 	(void) sigaction(SIGQUIT, &sa, NULL);
714 	(void) sigaction(SIGTERM, &sa, NULL);
715 	sa.sa_handler = lostconn;
716 	(void) sigaction(SIGPIPE, &sa, NULL);
717 	sa.sa_handler = toolong;
718 	(void) sigaction(SIGALRM, &sa, NULL);
719 	sa.sa_handler = sigurg;
720 	(void) sigaction(SIGURG, &sa, NULL);
721 
722 	/* Try to handle urgent data inline */
723 #ifdef SO_OOBINLINE
724 	if (setsockopt(0, SOL_SOCKET, SO_OOBINLINE, (char *)&on, sizeof(on)) < 0)
725 		syslog(LOG_WARNING, "setsockopt: %m");
726 #endif
727 	/* Set keepalives on the socket to detect dropped connections.  */
728 #ifdef SO_KEEPALIVE
729 	keepalive = 1;
730 	if (setsockopt(0, SOL_SOCKET, SO_KEEPALIVE, (char *)&keepalive,
731 	    sizeof(int)) < 0)
732 		syslog(LOG_WARNING, "setsockopt (SO_KEEPALIVE): %m");
733 #endif
734 
735 #ifdef	F_SETOWN
736 	if (fcntl(fileno(stdin), F_SETOWN, getpid()) == -1)
737 		syslog(LOG_WARNING, "fcntl F_SETOWN: %m");
738 #endif
739 	logremotehost(&his_addr);
740 	/*
741 	 * Set up default state
742 	 */
743 	data = -1;
744 	type = TYPE_A;
745 	form = FORM_N;
746 	stru = STRU_F;
747 	mode = MODE_S;
748 	tmpline[0] = '\0';
749 	hasyyerrored = 0;
750 
751 #ifdef KERBEROS5
752 	kerror = krb5_init_context(&kcontext);
753 	if (kerror) {
754 		syslog(LOG_ERR, "%s when initializing Kerberos context",
755 		    error_message(kerror));
756 		exit(0);
757 	}
758 #endif /* KERBEROS5 */
759 
760 	init_curclass();
761 	curclass.timeout = 300;		/* 5 minutes, as per login(1) */
762 	curclass.type = CLASS_REAL;
763 
764 	/* If logins are disabled, print out the message. */
765 	if (display_file(_PATH_NOLOGIN, 530)) {
766 		reply(530, "System not available.");
767 		exit(0);
768 	}
769 	(void)display_file(conffilename(_NAME_FTPWELCOME), 220);
770 		/* reply(220,) must follow */
771 	if (EMPTYSTR(version))
772 		reply(220, "%s FTP server ready.", hostname);
773 	else
774 		reply(220, "%s FTP server (%s) ready.", hostname, version);
775 
776 	if (xferlogname != NULL) {
777 		xferlogfd = open(xferlogname, O_WRONLY | O_APPEND | O_CREAT,
778 		    0660);
779 		if (xferlogfd == -1)
780 			syslog(LOG_WARNING, "open xferlog `%s': %m",
781 			    xferlogname);
782 		else
783 			doxferlog |= 2;
784 	}
785 
786 	ftp_loop();
787 	/* NOTREACHED */
788 }
789 
790 static void
lostconn(int signo __unused)791 lostconn(int signo __unused)
792 {
793 
794 	if (ftpd_debug)
795 		syslog(LOG_DEBUG, "lost connection");
796 	dologout(1);
797 }
798 
799 static void
toolong(int signo __unused)800 toolong(int signo __unused)
801 {
802 
803 		/* XXXSIGRACE */
804 	reply(421,
805 	    "Timeout (" LLF " seconds): closing control connection.",
806 	    (LLT)curclass.timeout);
807 	if (logging)
808 		syslog(LOG_INFO, "User %s timed out after " LLF " seconds",
809 		    (pw ? pw->pw_name : "unknown"), (LLT)curclass.timeout);
810 	dologout(1);
811 }
812 
813 static void
sigquit(int signo)814 sigquit(int signo)
815 {
816 
817 	if (ftpd_debug)
818 		syslog(LOG_DEBUG, "got signal %d", signo);
819 	dologout(1);
820 }
821 
822 static void
sigurg(int signo __unused)823 sigurg(int signo __unused)
824 {
825 
826 	urgflag = 1;
827 }
828 
829 
830 /*
831  * Save the result of a getpwnam.  Used for USER command, since
832  * the data returned must not be clobbered by any other command
833  * (e.g., globbing).
834  */
835 static struct passwd *
sgetpwnam(const char * name)836 sgetpwnam(const char *name)
837 {
838 	static struct passwd save;
839 	struct passwd *p;
840 
841 	if ((p = getpwnam(name)) == NULL)
842 		return (p);
843 	if (save.pw_name) {
844 		free((char *)save.pw_name);
845 		memset(save.pw_passwd, 0, strlen(save.pw_passwd));
846 		free((char *)save.pw_passwd);
847 		free((char *)save.pw_gecos);
848 		free((char *)save.pw_dir);
849 		free((char *)save.pw_shell);
850 	}
851 	save = *p;
852 	save.pw_name = ftpd_strdup(p->pw_name);
853 	save.pw_passwd = ftpd_strdup(p->pw_passwd);
854 	save.pw_gecos = ftpd_strdup(p->pw_gecos);
855 	save.pw_dir = ftpd_strdup(p->pw_dir);
856 	save.pw_shell = ftpd_strdup(p->pw_shell);
857 	return (&save);
858 }
859 
860 static int	login_attempts;	/* number of failed login attempts */
861 static int	askpasswd;	/* had USER command, ask for PASSwd */
862 static int	permitted;	/* USER permitted */
863 
864 /*
865  * USER command.
866  * Sets global passwd pointer pw if named account exists and is acceptable;
867  * sets askpasswd if a PASS command is expected.  If logged in previously,
868  * need to reset state.  If name is "ftp" or "anonymous", the name is not in
869  * _NAME_FTPUSERS, and ftp account exists, set guest and pw, then just return.
870  * If account doesn't exist, ask for passwd anyway.  Otherwise, check user
871  * requesting login privileges.  Disallow anyone who does not have a standard
872  * shell as returned by getusershell().  Disallow anyone mentioned in the file
873  * _NAME_FTPUSERS to allow people such as root and uucp to be avoided.
874  */
875 void
user(const char * name)876 user(const char *name)
877 {
878 	char	*class;
879 #ifdef	LOGIN_CAP
880 	login_cap_t *lc = NULL;
881 #endif
882 #ifdef USE_PAM
883 	int e;
884 #endif
885 
886 	class = NULL;
887 	if (logged_in) {
888 		switch (curclass.type) {
889 		case CLASS_GUEST:
890 			reply(530, "Can't change user from guest login.");
891 			return;
892 		case CLASS_CHROOT:
893 			reply(530, "Can't change user from chroot user.");
894 			return;
895 		case CLASS_REAL:
896 			if (dropprivs) {
897 				reply(530, "Can't change user.");
898 				return;
899 			}
900 			end_login();
901 			break;
902 		default:
903 			abort();
904 		}
905 	}
906 
907 #if defined(KERBEROS)
908 	kdestroy();
909 #endif
910 #if defined(KERBEROS5)
911 	k5destroy();
912 #endif
913 
914 	curclass.type = CLASS_REAL;
915 	askpasswd = 0;
916 	permitted = 0;
917 
918 	if (strcmp(name, "ftp") == 0 || strcmp(name, "anonymous") == 0) {
919 			/* need `pw' setup for checkaccess() and checkuser () */
920 		if ((pw = sgetpwnam("ftp")) == NULL)
921 			reply(530, "User %s unknown.", name);
922 		else if (! checkaccess("ftp") || ! checkaccess("anonymous"))
923 			reply(530, "User %s access denied.", name);
924 		else {
925 			curclass.type = CLASS_GUEST;
926 			askpasswd = 1;
927 			reply(331,
928 			    "Guest login ok, type your name as password.");
929 		}
930 		if (!askpasswd) {
931 			if (logging)
932 				syslog(LOG_NOTICE,
933 				    "ANONYMOUS FTP LOGIN REFUSED FROM %s",
934 				    remoteloghost);
935 			end_login();
936 			goto cleanup_user;
937 		}
938 		name = "ftp";
939 	} else
940 		pw = sgetpwnam(name);
941 
942 	strlcpy(curname, name, curname_len);
943 
944 			/* check user in /etc/ftpusers, and setup class */
945 	permitted = checkuser(_NAME_FTPUSERS, curname, 1, 0, &class);
946 
947 			/* check user in /etc/ftpchroot */
948 #ifdef	LOGIN_CAP
949 	lc = login_getpwclass(pw);
950 #endif
951 	if (checkuser(_NAME_FTPCHROOT, curname, 0, 0, NULL)
952 #ifdef	LOGIN_CAP	/* Allow login.conf configuration as well */
953 	    || login_getcapbool(lc, "ftp-chroot", 0)
954 #endif
955 	) {
956 		if (curclass.type == CLASS_GUEST) {
957 			syslog(LOG_NOTICE,
958 	    "Can't change guest user to chroot class; remove entry in %s",
959 			    _NAME_FTPCHROOT);
960 			exit(1);
961 		}
962 		curclass.type = CLASS_CHROOT;
963 	}
964 
965 			/* determine default class */
966 	if (class == NULL) {
967 		switch (curclass.type) {
968 		case CLASS_GUEST:
969 			class = ftpd_strdup("guest");
970 			break;
971 		case CLASS_CHROOT:
972 			class = ftpd_strdup("chroot");
973 			break;
974 		case CLASS_REAL:
975 			class = ftpd_strdup("real");
976 			break;
977 		default:
978 			syslog(LOG_ERR, "unknown curclass.type %d; aborting",
979 			    curclass.type);
980 			abort();
981 		}
982 	}
983 			/* parse ftpd.conf, setting up various parameters */
984 	parse_conf(class);
985 			/* if not guest user, check for valid shell */
986 	if (pw == NULL)
987 		permitted = 0;
988 	else {
989 		const char	*cp, *shell;
990 
991 		if ((shell = pw->pw_shell) == NULL || *shell == 0)
992 			shell = _PATH_BSHELL;
993 		while ((cp = getusershell()) != NULL)
994 			if (strcmp(cp, shell) == 0)
995 				break;
996 		endusershell();
997 		if (cp == NULL && curclass.type != CLASS_GUEST)
998 			permitted = 0;
999 	}
1000 
1001 			/* deny quickly (after USER not PASS) if requested */
1002 	if (CURCLASS_FLAGS_ISSET(denyquick) && !permitted) {
1003 		reply(530, "User %s may not use FTP.", curname);
1004 		if (logging)
1005 			syslog(LOG_NOTICE, "FTP LOGIN REFUSED FROM %s, %s",
1006 			    remoteloghost, curname);
1007 		end_login();
1008 		goto cleanup_user;
1009 	}
1010 
1011 			/* if haven't asked yet (i.e, not anon), ask now */
1012 	if (!askpasswd) {
1013 		askpasswd = 1;
1014 #ifdef USE_PAM
1015 		e = auth_pam();		/* this does reply(331, ...) */
1016 		do_pass(1, e, "");
1017 		goto cleanup_user;
1018 #else /* !USE_PAM */
1019 #ifdef SKEY
1020 		if (skey_haskey(curname) == 0) {
1021 			const char *myskey;
1022 
1023 			myskey = skey_keyinfo(curname);
1024 			reply(331, "Password [ %s ] required for %s.",
1025 			    myskey ? myskey : "error getting challenge",
1026 			    curname);
1027 		} else
1028 #endif
1029 			reply(331, "Password required for %s.", curname);
1030 #endif /* !USE_PAM */
1031 	}
1032 
1033  cleanup_user:
1034 #ifdef LOGIN_CAP
1035 	login_close(lc);
1036 #endif
1037 	/*
1038 	 * Delay before reading passwd after first failed
1039 	 * attempt to slow down passwd-guessing programs.
1040 	 */
1041 	if (login_attempts)
1042 		sleep((unsigned) login_attempts);
1043 
1044 	if (class)
1045 		free(class);
1046 }
1047 
1048 /*
1049  * Determine whether something is to happen (allow access, chroot)
1050  * for a user. Each line is a shell-style glob followed by
1051  * `yes' or `no'.
1052  *
1053  * For backward compatibility, `allow' and `deny' are synonymns
1054  * for `yes' and `no', respectively.
1055  *
1056  * Each glob is matched against the username in turn, and the first
1057  * match found is used. If no match is found, the result is the
1058  * argument `def'. If a match is found but without and explicit
1059  * `yes'/`no', the result is the opposite of def.
1060  *
1061  * If the file doesn't exist at all, the result is the argument
1062  * `nofile'
1063  *
1064  * Any line starting with `#' is considered a comment and ignored.
1065  *
1066  * Returns 0 if the user is denied, or 1 if they are allowed.
1067  *
1068  * NOTE: needs struct passwd *pw setup before use.
1069  */
1070 static int
checkuser(const char * fname,const char * name,int def,int nofile,char ** retclass)1071 checkuser(const char *fname, const char *name, int def, int nofile,
1072 	    char **retclass)
1073 {
1074 	FILE	*fd;
1075 	int	 retval;
1076 	char	*word, *perm, *class, *buf, *p;
1077 	size_t	 len, line;
1078 
1079 	retval = def;
1080 	if (retclass != NULL)
1081 		*retclass = NULL;
1082 	if ((fd = fopen(conffilename(fname), "r")) == NULL)
1083 		return nofile;
1084 
1085 	line = 0;
1086 	for (;
1087 	    (buf = fparseln(fd, &len, &line, NULL, FPARSELN_UNESCCOMM |
1088 			    FPARSELN_UNESCCONT | FPARSELN_UNESCESC)) != NULL;
1089 	    free(buf), buf = NULL) {
1090 		word = perm = class = NULL;
1091 		p = buf;
1092 		if (len < 1)
1093 			continue;
1094 		if (p[len - 1] == '\n')
1095 			p[--len] = '\0';
1096 		if (EMPTYSTR(p))
1097 			continue;
1098 
1099 		NEXTWORD(p, word);
1100 		NEXTWORD(p, perm);
1101 		NEXTWORD(p, class);
1102 		if (EMPTYSTR(word))
1103 			continue;
1104 		if (!EMPTYSTR(class)) {
1105 			if (strcasecmp(class, "all") == 0 ||
1106 			    strcasecmp(class, "none") == 0) {
1107 				syslog(LOG_WARNING,
1108 		"%s line %d: illegal user-defined class `%s' - skipping entry",
1109 					    fname, (int)line, class);
1110 				continue;
1111 			}
1112 		}
1113 
1114 					/* have a host specifier */
1115 		if ((p = strchr(word, '@')) != NULL) {
1116 			unsigned char	net[16], mask[16], *addr;
1117 			int		addrlen, bits, bytes, a;
1118 
1119 			*p++ = '\0';
1120 					/* check against network or CIDR */
1121 			memset(net, 0x00, sizeof(net));
1122 			if ((bits = inet_net_pton(his_addr.su_family, p, net,
1123 			    sizeof(net))) != -1) {
1124 #ifdef INET6
1125 				if (his_addr.su_family == AF_INET) {
1126 #endif
1127 					addrlen = 4;
1128 					addr = (unsigned char *)&his_addr.su_addr;
1129 #ifdef INET6
1130 				} else {
1131 					addrlen = 16;
1132 					addr = (unsigned char *)&his_addr.su_6addr;
1133 				}
1134 #endif
1135 				bytes = bits / 8;
1136 				bits = bits % 8;
1137 				if (bytes > 0)
1138 					memset(mask, 0xFF, bytes);
1139 				if (bytes < addrlen)
1140 					mask[bytes] = 0xFF << (8 - bits);
1141 				if (bytes + 1 < addrlen)
1142 					memset(mask + bytes + 1, 0x00,
1143 					    addrlen - bytes - 1);
1144 				for (a = 0; a < addrlen; a++)
1145 					if ((addr[a] & mask[a]) != net[a])
1146 						break;
1147 				if (a < addrlen)
1148 					continue;
1149 
1150 					/* check against hostname glob */
1151 			} else if (fnmatch(p, remotehost, FNM_CASEFOLD) != 0)
1152 				continue;
1153 		}
1154 
1155 					/* have a group specifier */
1156 		if ((p = strchr(word, ':')) != NULL) {
1157 			gid_t	*groups, *ng;
1158 			int	 gsize, i, found;
1159 
1160 			if (pw == NULL)
1161 				continue;	/* no match for unknown user */
1162 			*p++ = '\0';
1163 			groups = NULL;
1164 			gsize = 16;
1165 			do {
1166 				ng = realloc(groups, gsize * sizeof(gid_t));
1167 				if (ng == NULL)
1168 					fatal(
1169 					    "Local resource failure: realloc");
1170 				groups = ng;
1171 			} while (getgrouplist(pw->pw_name, pw->pw_gid,
1172 						groups, &gsize) == -1);
1173 			found = 0;
1174 			for (i = 0; i < gsize; i++) {
1175 				struct group *g;
1176 
1177 				if ((g = getgrgid(groups[i])) == NULL)
1178 					continue;
1179 				if (fnmatch(p, g->gr_name, 0) == 0) {
1180 					found = 1;
1181 					break;
1182 				}
1183 			}
1184 			free(groups);
1185 			if (!found)
1186 				continue;
1187 		}
1188 
1189 					/* check against username glob */
1190 		if (fnmatch(word, name, 0) != 0)
1191 			continue;
1192 
1193 		if (perm != NULL &&
1194 		    ((strcasecmp(perm, "allow") == 0) ||
1195 		     (strcasecmp(perm, "yes") == 0)))
1196 			retval = 1;
1197 		else if (perm != NULL &&
1198 		    ((strcasecmp(perm, "deny") == 0) ||
1199 		     (strcasecmp(perm, "no") == 0)))
1200 			retval = 0;
1201 		else
1202 			retval = !def;
1203 		if (!EMPTYSTR(class) && retclass != NULL)
1204 			*retclass = ftpd_strdup(class);
1205 		free(buf);
1206 		break;
1207 	}
1208 	(void) fclose(fd);
1209 	return (retval);
1210 }
1211 
1212 /*
1213  * Check if user is allowed by /etc/ftpusers
1214  * returns 1 for yes, 0 for no
1215  *
1216  * NOTE: needs struct passwd *pw setup (for checkuser())
1217  */
1218 static int
checkaccess(const char * name)1219 checkaccess(const char *name)
1220 {
1221 
1222 	return (checkuser(_NAME_FTPUSERS, name, 1, 0, NULL));
1223 }
1224 
1225 static void
login_utmp(const char * line,const char * name,const char * host,struct sockinet * haddr)1226 login_utmp(const char *line, const char *name, const char *host,
1227     struct sockinet *haddr)
1228 {
1229 #if defined(SUPPORT_UTMPX) || defined(SUPPORT_UTMP)
1230 	struct timeval tv;
1231 	(void)gettimeofday(&tv, NULL);
1232 #endif
1233 #ifdef SUPPORT_UTMPX
1234 	if (doutmp) {
1235 		(void)memset(&utmpx, 0, sizeof(utmpx));
1236 		utmpx.ut_tv = tv;
1237 		utmpx.ut_pid = getpid();
1238 		utmpx.ut_id[0] = 'f';
1239 		utmpx.ut_id[1] = 't';
1240 		utmpx.ut_id[2] = 'p';
1241 		utmpx.ut_id[3] = '*';
1242 		utmpx.ut_type = USER_PROCESS;
1243 		(void)strncpy(utmpx.ut_name, name, sizeof(utmpx.ut_name));
1244 		(void)strncpy(utmpx.ut_line, line, sizeof(utmpx.ut_line));
1245 		(void)strncpy(utmpx.ut_host, host, sizeof(utmpx.ut_host));
1246 		(void)memcpy(&utmpx.ut_ss, &haddr->si_su, haddr->su_len);
1247 		ftpd_loginx(&utmpx);
1248 	}
1249 	if (dowtmp)
1250 		ftpd_logwtmpx(line, name, host, haddr, 0, USER_PROCESS);
1251 #endif
1252 #ifdef SUPPORT_UTMP
1253 	if (doutmp) {
1254 		(void)memset(&utmp, 0, sizeof(utmp));
1255 		(void)time(&utmp.ut_time);
1256 		(void)strncpy(utmp.ut_name, name, sizeof(utmp.ut_name));
1257 		(void)strncpy(utmp.ut_line, line, sizeof(utmp.ut_line));
1258 		(void)strncpy(utmp.ut_host, host, sizeof(utmp.ut_host));
1259 		ftpd_login(&utmp);
1260 	}
1261 	if (dowtmp)
1262 		ftpd_logwtmp(line, name, host);
1263 #endif
1264 }
1265 
1266 static void
logout_utmp(void)1267 logout_utmp(void)
1268 {
1269 #ifdef SUPPORT_UTMPX
1270 	int okwtmpx = dowtmp;
1271 #endif
1272 #ifdef SUPPORT_UTMP
1273 	int okwtmp = dowtmp;
1274 #endif
1275 	if (logged_in) {
1276 #ifdef SUPPORT_UTMPX
1277 		if (doutmp)
1278 			okwtmpx &= ftpd_logoutx(ttyline, 0, DEAD_PROCESS);
1279 		if (okwtmpx)
1280 			ftpd_logwtmpx(ttyline, "", "", NULL, 0, DEAD_PROCESS);
1281 #endif
1282 #ifdef SUPPORT_UTMP
1283 		if (doutmp)
1284 			okwtmp &= ftpd_logout(ttyline);
1285 		if (okwtmp)
1286 			ftpd_logwtmp(ttyline, "", "");
1287 #endif
1288 	}
1289 }
1290 
1291 /*
1292  * Terminate login as previous user (if any), resetting state;
1293  * used when USER command is given or login fails.
1294  */
1295 static void
end_login(void)1296 end_login(void)
1297 {
1298 #ifdef USE_PAM
1299 	int e;
1300 #endif
1301 	logout_utmp();
1302 	show_chdir_messages(-1);		/* flush chdir cache */
1303 	if (pw != NULL && pw->pw_passwd != NULL)
1304 		memset(pw->pw_passwd, 0, strlen(pw->pw_passwd));
1305 	pw = NULL;
1306 	logged_in = 0;
1307 	askpasswd = 0;
1308 	permitted = 0;
1309 	quietmessages = 0;
1310 	gidcount = 0;
1311 	curclass.type = CLASS_REAL;
1312 	(void) seteuid((uid_t)0);
1313 #ifdef	LOGIN_CAP
1314 	setusercontext(NULL, getpwuid(0), 0,
1315 		       LOGIN_SETPRIORITY|LOGIN_SETRESOURCES|LOGIN_SETUMASK);
1316 #endif
1317 #ifdef USE_PAM
1318 	if (pamh) {
1319 		if ((e = pam_setcred(pamh, PAM_DELETE_CRED)) != PAM_SUCCESS)
1320 			syslog(LOG_ERR, "pam_setcred: %s",
1321 			    pam_strerror(pamh, e));
1322 		if ((e = pam_close_session(pamh,0)) != PAM_SUCCESS)
1323 			syslog(LOG_ERR, "pam_close_session: %s",
1324 			    pam_strerror(pamh, e));
1325 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS)
1326 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1327 		pamh = NULL;
1328 	}
1329 #endif
1330 }
1331 
1332 void
pass(const char * passwd)1333 pass(const char *passwd)
1334 {
1335 	do_pass(0, 0, passwd);
1336 }
1337 
1338 /*
1339  * Perform the passwd confirmation and login.
1340  *
1341  * If pass_checked is zero, confirm passwd is correct, & ignore pass_rval.
1342  * This is the traditional PASS implementation.
1343  *
1344  * If pass_checked is non-zero, use pass_rval and ignore passwd.
1345  * This is used by auth_pam() which has already parsed PASS.
1346  * This only applies to curclass.type != CLASS_GUEST.
1347  */
1348 static void
do_pass(int pass_checked,int pass_rval,const char * passwd)1349 do_pass(int pass_checked, int pass_rval, const char *passwd)
1350 {
1351 	int		 rval;
1352 	char		 root[MAXPATHLEN];
1353 #ifdef	LOGIN_CAP
1354 	login_cap_t *lc = NULL;
1355 #endif
1356 #ifdef USE_PAM
1357 	int e;
1358 #endif
1359 
1360 	rval = 1;
1361 
1362 	if (logged_in || askpasswd == 0) {
1363 		reply(503, "Login with USER first.");
1364 		return;
1365 	}
1366 	askpasswd = 0;
1367 	if (curclass.type != CLASS_GUEST) {
1368 			/* "ftp" is the only account allowed with no password */
1369 		if (pw == NULL) {
1370 			rval = 1;	/* failure below */
1371 			goto skip;
1372 		}
1373 		if (pass_checked) {	/* password validated in user() */
1374 			rval = pass_rval;
1375 			goto skip;
1376 		}
1377 #ifdef USE_PAM
1378 		syslog(LOG_ERR, "do_pass: USE_PAM shouldn't get here");
1379 		rval = 1;
1380 		goto skip;
1381 #endif
1382 #if defined(KERBEROS)
1383 		if (klogin(pw, "", hostname, (char *)passwd) == 0) {
1384 			rval = 0;
1385 			goto skip;
1386 		}
1387 #endif
1388 #if defined(KERBEROS5)
1389 		if (k5login(pw, "", hostname, (char *)passwd) == 0) {
1390 			rval = 0;
1391 			goto skip;
1392 		}
1393 #endif
1394 #ifdef SKEY
1395 		if (skey_haskey(pw->pw_name) == 0) {
1396 			char *p;
1397 			int r;
1398 
1399 			p = ftpd_strdup(passwd);
1400 			r = skey_passcheck(pw->pw_name, p);
1401 			free(p);
1402 			if (r != -1) {
1403 				rval = 0;
1404 				goto skip;
1405 			}
1406 		}
1407 #endif
1408 		if (!sflag)
1409 			rval = checkpassword(pw, passwd);
1410 		else
1411 			rval = 1;
1412 
1413  skip:
1414 
1415 			/*
1416 			 * If rval > 0, the user failed the authentication check
1417 			 * above.  If rval == 0, either Kerberos or local
1418 			 * authentication succeeded.
1419 			 */
1420 		if (rval) {
1421 			reply(530, "%s", rval == 2 ? "Password expired." :
1422 			    "Login incorrect.");
1423 			pfilter_notify(1, rval == 2 ? "exppass" : "badpass");
1424 			if (logging) {
1425 				syslog(LOG_NOTICE,
1426 				    "FTP LOGIN FAILED FROM %s", remoteloghost);
1427 				syslog(LOG_AUTHPRIV | LOG_NOTICE,
1428 				    "FTP LOGIN FAILED FROM %s, %s",
1429 				    remoteloghost, curname);
1430 			}
1431 			pw = NULL;
1432 			if (login_attempts++ >= 5) {
1433 				syslog(LOG_NOTICE,
1434 				    "repeated login failures from %s",
1435 				    remoteloghost);
1436 				exit(0);
1437 			}
1438 			return;
1439 		}
1440 	}
1441 
1442 			/* password ok; check if anything else prevents login */
1443 	if (! permitted) {
1444 		reply(530, "User %s may not use FTP.", pw->pw_name);
1445 		if (logging)
1446 			syslog(LOG_NOTICE, "FTP LOGIN REFUSED FROM %s, %s",
1447 			    remoteloghost, pw->pw_name);
1448 		goto bad;
1449 	}
1450 
1451 	login_attempts = 0;		/* this time successful */
1452 	if (setegid((gid_t)pw->pw_gid) < 0) {
1453 		reply(550, "Can't set gid.");
1454 		goto bad;
1455 	}
1456 #ifdef	LOGIN_CAP
1457 	if ((lc = login_getpwclass(pw)) != NULL) {
1458 #ifdef notyet
1459 		char	remote_ip[NI_MAXHOST];
1460 
1461 		if (getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
1462 			remote_ip, sizeof(remote_ip) - 1, NULL, 0,
1463 			NI_NUMERICHOST))
1464 				*remote_ip = 0;
1465 		remote_ip[sizeof(remote_ip) - 1] = 0;
1466 		if (!auth_hostok(lc, remotehost, remote_ip)) {
1467 			pfilter_notify(1, "bannedhost");
1468 			syslog(LOG_INFO|LOG_AUTH,
1469 			    "FTP LOGIN FAILED (HOST) as %s: permission denied.",
1470 			    pw->pw_name);
1471 			reply(530, "Permission denied.");
1472 			pw = NULL;
1473 			return;
1474 		}
1475 		if (!auth_timeok(lc, time(NULL))) {
1476 			reply(530, "Login not available right now.");
1477 			pw = NULL;
1478 			return;
1479 		}
1480 #endif
1481 	}
1482 	setsid();
1483 	setusercontext(lc, pw, 0,
1484 		LOGIN_SETLOGIN|LOGIN_SETGROUP|LOGIN_SETPRIORITY|
1485 		LOGIN_SETRESOURCES|LOGIN_SETUMASK);
1486 #else
1487 	(void) initgroups(pw->pw_name, pw->pw_gid);
1488 			/* cache groups for cmds.c::matchgroup() */
1489 #endif
1490 #ifdef USE_PAM
1491 	if (pamh) {
1492 		if ((e = pam_open_session(pamh, 0)) != PAM_SUCCESS) {
1493 			syslog(LOG_ERR, "pam_open_session: %s",
1494 			    pam_strerror(pamh, e));
1495 		} else if ((e = pam_setcred(pamh, PAM_ESTABLISH_CRED))
1496 		    != PAM_SUCCESS) {
1497 			syslog(LOG_ERR, "pam_setcred: %s",
1498 			    pam_strerror(pamh, e));
1499 		}
1500 	}
1501 #endif
1502 	gidcount = getgroups(0, NULL);
1503 	if (gidlist)
1504 		free(gidlist);
1505 	gidlist = malloc(gidcount * sizeof *gidlist);
1506 	gidcount = getgroups(gidcount, gidlist);
1507 
1508 	/* open utmp/wtmp before chroot */
1509 	login_utmp(ttyline, pw->pw_name, remotehost, &his_addr);
1510 
1511 	logged_in = 1;
1512 
1513 	connections = 1;
1514 	if (dopidfile)
1515 		count_users();
1516 	if (curclass.limit != -1 && connections > curclass.limit) {
1517 		if (! EMPTYSTR(curclass.limitfile))
1518 			(void)display_file(conffilename(curclass.limitfile),
1519 			    530);
1520 		reply(530,
1521 		    "User %s access denied, connection limit of " LLF
1522 		    " reached.",
1523 		    pw->pw_name, (LLT)curclass.limit);
1524 		syslog(LOG_NOTICE,
1525 		    "Maximum connection limit of " LLF
1526 		    " for class %s reached, login refused for %s",
1527 		    (LLT)curclass.limit, curclass.classname, pw->pw_name);
1528 		goto bad;
1529 	}
1530 
1531 	homedir[0] = '/';
1532 	switch (curclass.type) {
1533 	case CLASS_GUEST:
1534 			/*
1535 			 * We MUST do a chdir() after the chroot. Otherwise
1536 			 * the old current directory will be accessible as "."
1537 			 * outside the new root!
1538 			 */
1539 		format_path(root,
1540 		    curclass.chroot ? curclass.chroot :
1541 		    anondir ? anondir :
1542 		    pw->pw_dir);
1543 		format_path(homedir,
1544 		    curclass.homedir ? curclass.homedir :
1545 		    "/");
1546 		if (EMPTYSTR(homedir))
1547 			homedir[0] = '/';
1548 		if (EMPTYSTR(root) || chroot(root) < 0) {
1549 			syslog(LOG_NOTICE,
1550 			    "GUEST user %s: can't chroot to %s: %m",
1551 			    pw->pw_name, root);
1552 			goto bad_guest;
1553 		}
1554 		if (chdir(homedir) < 0) {
1555 			syslog(LOG_NOTICE,
1556 			    "GUEST user %s: can't chdir to %s: %m",
1557 			    pw->pw_name, homedir);
1558  bad_guest:
1559 			reply(550, "Can't set guest privileges.");
1560 			goto bad;
1561 		}
1562 		break;
1563 	case CLASS_CHROOT:
1564 		format_path(root,
1565 		    curclass.chroot ? curclass.chroot :
1566 		    pw->pw_dir);
1567 		format_path(homedir,
1568 		    curclass.homedir ? curclass.homedir :
1569 		    "/");
1570 		if (EMPTYSTR(homedir))
1571 			homedir[0] = '/';
1572 		if (EMPTYSTR(root) || chroot(root) < 0) {
1573 			syslog(LOG_NOTICE,
1574 			    "CHROOT user %s: can't chroot to %s: %m",
1575 			    pw->pw_name, root);
1576 			goto bad_chroot;
1577 		}
1578 		if (chdir(homedir) < 0) {
1579 			syslog(LOG_NOTICE,
1580 			    "CHROOT user %s: can't chdir to %s: %m",
1581 			    pw->pw_name, homedir);
1582  bad_chroot:
1583 			reply(550, "Can't change root.");
1584 			goto bad;
1585 		}
1586 		break;
1587 	case CLASS_REAL:
1588 			/* only chroot REAL if explicitly requested */
1589 		if (! EMPTYSTR(curclass.chroot)) {
1590 			format_path(root, curclass.chroot);
1591 			if (EMPTYSTR(root) || chroot(root) < 0) {
1592 				syslog(LOG_NOTICE,
1593 				    "REAL user %s: can't chroot to %s: %m",
1594 				    pw->pw_name, root);
1595 				goto bad_chroot;
1596 			}
1597 		}
1598 		format_path(homedir,
1599 		    curclass.homedir ? curclass.homedir :
1600 		    pw->pw_dir);
1601 		if (EMPTYSTR(homedir) || chdir(homedir) < 0) {
1602 			if (chdir("/") < 0) {
1603 				syslog(LOG_NOTICE,
1604 				    "REAL user %s: can't chdir to %s: %m",
1605 				    pw->pw_name,
1606 				    !EMPTYSTR(homedir) ?  homedir : "/");
1607 				reply(530,
1608 				    "User %s: can't change directory to %s.",
1609 				    pw->pw_name,
1610 				    !EMPTYSTR(homedir) ? homedir : "/");
1611 				goto bad;
1612 			} else {
1613 				reply(-230,
1614 				    "No directory! Logging in with home=/");
1615 				homedir[0] = '/';
1616 			}
1617 		}
1618 		break;
1619 	}
1620 #ifndef LOGIN_CAP
1621 	setsid();
1622 #if !defined(__minix)
1623 	setlogin(pw->pw_name);
1624 #endif /* !defined(__minix) */
1625 #endif
1626 	if (dropprivs ||
1627 	    (curclass.type != CLASS_REAL &&
1628 	    ntohs(ctrl_addr.su_port) > IPPORT_RESERVED + 1)) {
1629 		dropprivs++;
1630 		if (setgid((gid_t)pw->pw_gid) < 0) {
1631 			reply(550, "Can't set gid.");
1632 			goto bad;
1633 		}
1634 		if (setuid((uid_t)pw->pw_uid) < 0) {
1635 			reply(550, "Can't set uid.");
1636 			goto bad;
1637 		}
1638 	} else {
1639 		if (seteuid((uid_t)pw->pw_uid) < 0) {
1640 			reply(550, "Can't set uid.");
1641 			goto bad;
1642 		}
1643 	}
1644 	setenv("HOME", homedir, 1);
1645 
1646 	if (curclass.type == CLASS_GUEST && passwd[0] == '-')
1647 		quietmessages = 1;
1648 
1649 			/*
1650 			 * Display a login message, if it exists.
1651 			 * N.B. reply(230,) must follow the message.
1652 			 */
1653 	if (! EMPTYSTR(curclass.motd))
1654 		(void)display_file(conffilename(curclass.motd), 230);
1655 	show_chdir_messages(230);
1656 	if (curclass.type == CLASS_GUEST) {
1657 		char *p;
1658 
1659 		reply(230, "Guest login ok, access restrictions apply.");
1660 #if defined(HAVE_SETPROCTITLE)
1661 		snprintf(proctitle, sizeof(proctitle),
1662 		    "%s: anonymous/%s", remotehost, passwd);
1663 		setproctitle("%s", proctitle);
1664 #endif /* defined(HAVE_SETPROCTITLE) */
1665 		if (logging)
1666 			syslog(LOG_INFO,
1667 			"ANONYMOUS FTP LOGIN FROM %s, %s (class: %s, type: %s)",
1668 			    remoteloghost, passwd,
1669 			    curclass.classname, CURCLASSTYPE);
1670 			/* store guest password reply into pw_passwd */
1671 		REASSIGN(pw->pw_passwd, ftpd_strdup(passwd));
1672 		for (p = pw->pw_passwd; *p; p++)
1673 			if (!isgraph((unsigned char)*p))
1674 				*p = '_';
1675 	} else {
1676 		reply(230, "User %s logged in.", pw->pw_name);
1677 #if defined(HAVE_SETPROCTITLE)
1678 		snprintf(proctitle, sizeof(proctitle),
1679 		    "%s: %s", remotehost, pw->pw_name);
1680 		setproctitle("%s", proctitle);
1681 #endif /* defined(HAVE_SETPROCTITLE) */
1682 		if (logging)
1683 			syslog(LOG_INFO,
1684 			    "FTP LOGIN FROM %s as %s (class: %s, type: %s)",
1685 			    remoteloghost, pw->pw_name,
1686 			    curclass.classname, CURCLASSTYPE);
1687 	}
1688 	(void) umask(curclass.umask);
1689 #ifdef	LOGIN_CAP
1690 	login_close(lc);
1691 #endif
1692 	return;
1693 
1694  bad:
1695 #ifdef	LOGIN_CAP
1696 	login_close(lc);
1697 #endif
1698 			/* Forget all about it... */
1699 	end_login();
1700 }
1701 
1702 void
retrieve(const char * argv[],const char * name)1703 retrieve(const char *argv[], const char *name)
1704 {
1705 	FILE *fin, *dout;
1706 	struct stat st;
1707 	int (*closefunc)(FILE *) = NULL;
1708 	int dolog, sendrv, closerv, stderrfd, isconversion, isdata, isls;
1709 	struct timeval start, finish, td, *tdp;
1710 	struct rusage rusage_before, rusage_after;
1711 	const char *dispname;
1712 	const char *error;
1713 
1714 	sendrv = closerv = stderrfd = -1;
1715 	isconversion = isdata = isls = dolog = 0;
1716 	tdp = NULL;
1717 	dispname = name;
1718 	fin = dout = NULL;
1719 	error = NULL;
1720 	if (argv == NULL) {		/* if not running a command ... */
1721 		dolog = 1;
1722 		isdata = 1;
1723 		fin = fopen(name, "r");
1724 		closefunc = fclose;
1725 		if (fin == NULL)	/* doesn't exist?; try a conversion */
1726 			argv = do_conversion(name);
1727 		if (argv != NULL) {
1728 			isconversion++;
1729 			syslog(LOG_DEBUG, "get command: '%s' on '%s'",
1730 			    argv[0], name);
1731 		}
1732 	}
1733 	if (argv != NULL) {
1734 		char temp[MAXPATHLEN];
1735 
1736 		if (strcmp(argv[0], INTERNAL_LS) == 0) {
1737 			isls = 1;
1738 			stderrfd = -1;
1739 		} else {
1740 			(void)snprintf(temp, sizeof(temp), "%s", TMPFILE);
1741 			stderrfd = mkstemp(temp);
1742 			if (stderrfd != -1)
1743 				(void)unlink(temp);
1744 		}
1745 		dispname = argv[0];
1746 		fin = ftpd_popen(argv, "r", stderrfd);
1747 		closefunc = ftpd_pclose;
1748 		st.st_size = -1;
1749 		st.st_blksize = BUFSIZ;
1750 	}
1751 	if (fin == NULL) {
1752 		if (errno != 0) {
1753 			perror_reply(550, dispname);
1754 			if (dolog)
1755 				logxfer("get", -1, name, NULL, NULL,
1756 				    strerror(errno));
1757 		}
1758 		goto cleanupretrieve;
1759 	}
1760 	byte_count = -1;
1761 	if (argv == NULL
1762 	    && (fstat(fileno(fin), &st) < 0 || !S_ISREG(st.st_mode))) {
1763 		error = "Not a plain file";
1764 		reply(550, "%s: %s.", dispname, error);
1765 		goto done;
1766 	}
1767 	if (restart_point) {
1768 		if (type == TYPE_A) {
1769 			off_t i;
1770 			int c;
1771 
1772 			for (i = 0; i < restart_point; i++) {
1773 				if ((c=getc(fin)) == EOF) {
1774 					error = strerror(errno);
1775 					perror_reply(550, dispname);
1776 					goto done;
1777 				}
1778 				if (c == '\n')
1779 					i++;
1780 			}
1781 		} else if (lseek(fileno(fin), restart_point, SEEK_SET) < 0) {
1782 			error = strerror(errno);
1783 			perror_reply(550, dispname);
1784 			goto done;
1785 		}
1786 	}
1787 	dout = dataconn(dispname, st.st_size, "w");
1788 	if (dout == NULL)
1789 		goto done;
1790 
1791 	(void)getrusage(RUSAGE_SELF, &rusage_before);
1792 	(void)gettimeofday(&start, NULL);
1793 	sendrv = send_data(fin, dout, &st, isdata);
1794 	(void)gettimeofday(&finish, NULL);
1795 	(void)getrusage(RUSAGE_SELF, &rusage_after);
1796 	closedataconn(dout);		/* close now to affect timing stats */
1797 	timersub(&finish, &start, &td);
1798 	tdp = &td;
1799  done:
1800 	if (dolog) {
1801 		logxfer("get", byte_count, name, NULL, tdp, error);
1802 		if (tdp != NULL)
1803 			logrusage(&rusage_before, &rusage_after);
1804 	}
1805 	closerv = (*closefunc)(fin);
1806 	if (sendrv == 0) {
1807 		FILE *errf;
1808 		struct stat sb;
1809 
1810 		if (!isls && argv != NULL && closerv != 0) {
1811 			reply(-226,
1812 			    "Command returned an exit status of %d",
1813 			    closerv);
1814 			if (isconversion)
1815 				syslog(LOG_WARNING,
1816 				    "retrieve command: '%s' returned %d",
1817 				    argv[0], closerv);
1818 		}
1819 		if (!isls && argv != NULL && stderrfd != -1 &&
1820 		    (fstat(stderrfd, &sb) == 0) && sb.st_size > 0 &&
1821 		    ((errf = fdopen(stderrfd, "r")) != NULL)) {
1822 			char *cp, line[LINE_MAX];
1823 
1824 			reply(-226, "Command error messages:");
1825 			rewind(errf);
1826 			while (fgets(line, sizeof(line), errf) != NULL) {
1827 				if ((cp = strchr(line, '\n')) != NULL)
1828 					*cp = '\0';
1829 				reply(0, "  %s", line);
1830 			}
1831 			(void) fflush(stdout);
1832 			(void) fclose(errf);
1833 				/* a reply(226,) must follow */
1834 		}
1835 		reply(226, "Transfer complete.");
1836 	}
1837  cleanupretrieve:
1838 	if (stderrfd != -1)
1839 		(void)close(stderrfd);
1840 	if (isconversion)
1841 		free(argv);
1842 }
1843 
1844 void
store(const char * name,const char * fmode,int unique)1845 store(const char *name, const char *fmode, int unique)
1846 {
1847 	FILE *fout, *din;
1848 	struct stat st;
1849 	int (*closefunc)(FILE *);
1850 	struct timeval start, finish, td, *tdp;
1851 	const char *desc, *error;
1852 
1853 	din = NULL;
1854 	desc = (*fmode == 'w') ? "put" : "append";
1855 	error = NULL;
1856 	if (unique && stat(name, &st) == 0 &&
1857 	    (name = gunique(name)) == NULL) {
1858 		logxfer(desc, -1, name, NULL, NULL,
1859 		    "cannot create unique file");
1860 		goto cleanupstore;
1861 	}
1862 
1863 	if (restart_point)
1864 		fmode = "r+";
1865 	fout = fopen(name, fmode);
1866 	closefunc = fclose;
1867 	tdp = NULL;
1868 	if (fout == NULL) {
1869 		perror_reply(553, name);
1870 		logxfer(desc, -1, name, NULL, NULL, strerror(errno));
1871 		goto cleanupstore;
1872 	}
1873 	byte_count = -1;
1874 	if (restart_point) {
1875 		if (type == TYPE_A) {
1876 			off_t i;
1877 			int c;
1878 
1879 			for (i = 0; i < restart_point; i++) {
1880 				if ((c=getc(fout)) == EOF) {
1881 					error = strerror(errno);
1882 					perror_reply(550, name);
1883 					goto done;
1884 				}
1885 				if (c == '\n')
1886 					i++;
1887 			}
1888 			/*
1889 			 * We must do this seek to "current" position
1890 			 * because we are changing from reading to
1891 			 * writing.
1892 			 */
1893 			if (fseek(fout, 0L, SEEK_CUR) < 0) {
1894 				error = strerror(errno);
1895 				perror_reply(550, name);
1896 				goto done;
1897 			}
1898 		} else if (lseek(fileno(fout), restart_point, SEEK_SET) < 0) {
1899 			error = strerror(errno);
1900 			perror_reply(550, name);
1901 			goto done;
1902 		}
1903 	}
1904 	din = dataconn(name, (off_t)-1, "r");
1905 	if (din == NULL)
1906 		goto done;
1907 	(void)gettimeofday(&start, NULL);
1908 	if (receive_data(din, fout) == 0) {
1909 		if (unique)
1910 			reply(226, "Transfer complete (unique file name:%s).",
1911 			    name);
1912 		else
1913 			reply(226, "Transfer complete.");
1914 	}
1915 	(void)gettimeofday(&finish, NULL);
1916 	closedataconn(din);		/* close now to affect timing stats */
1917 	timersub(&finish, &start, &td);
1918 	tdp = &td;
1919  done:
1920 	logxfer(desc, byte_count, name, NULL, tdp, error);
1921 	(*closefunc)(fout);
1922  cleanupstore:
1923 	;
1924 }
1925 
1926 static FILE *
getdatasock(const char * fmode)1927 getdatasock(const char *fmode)
1928 {
1929 	int		on, s, t, tries;
1930 	in_port_t	port;
1931 
1932 	on = 1;
1933 	if (data >= 0)
1934 		return (fdopen(data, fmode));
1935 	if (! dropprivs)
1936 		(void) seteuid((uid_t)0);
1937 	s = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
1938 	if (s < 0)
1939 		goto bad;
1940 	if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR,
1941 	    (char *) &on, sizeof(on)) < 0)
1942 		goto bad;
1943 	if (setsockopt(s, SOL_SOCKET, SO_KEEPALIVE,
1944 	    (char *) &on, sizeof(on)) < 0)
1945 		goto bad;
1946 			/* anchor socket to avoid multi-homing problems */
1947 	data_source = ctrl_addr;
1948 			/*
1949 			 * By default source port for PORT connctions is
1950 			 * ctrlport-1 (see RFC959 section 5.2).
1951 			 * However, if privs have been dropped and that
1952 			 * would be < IPPORT_RESERVED, use a random port
1953 			 * instead.
1954 			 */
1955 	if (dataport)
1956 		port = dataport;
1957 	else
1958 		port = ntohs(ctrl_addr.su_port) - 1;
1959 	if (dropprivs && port < IPPORT_RESERVED)
1960 		port = 0;		/* use random port */
1961 	data_source.su_port = htons(port);
1962 
1963 	for (tries = 1; ; tries++) {
1964 		if (bind(s, (struct sockaddr *)&data_source.si_su,
1965 		    data_source.su_len) >= 0)
1966 			break;
1967 		if (errno != EADDRINUSE || tries > 10)
1968 			goto bad;
1969 		sleep(tries);
1970 	}
1971 	if (! dropprivs)
1972 		(void) seteuid((uid_t)pw->pw_uid);
1973 #ifdef IP_TOS
1974 	if (!mapped && ctrl_addr.su_family == AF_INET) {
1975 		on = IPTOS_THROUGHPUT;
1976 		if (setsockopt(s, IPPROTO_IP, IP_TOS, (char *)&on,
1977 			       sizeof(int)) < 0)
1978 			syslog(LOG_WARNING, "setsockopt (IP_TOS): %m");
1979 	}
1980 #endif
1981 	return (fdopen(s, fmode));
1982  bad:
1983 		/* Return the real value of errno (close may change it) */
1984 	t = errno;
1985 	if (! dropprivs)
1986 		(void) seteuid((uid_t)pw->pw_uid);
1987 	(void) close(s);
1988 	errno = t;
1989 	return (NULL);
1990 }
1991 
1992 FILE *
dataconn(const char * name,off_t size,const char * fmode)1993 dataconn(const char *name, off_t size, const char *fmode)
1994 {
1995 	char sizebuf[32];
1996 	FILE *file;
1997 	int retry, tos, keepalive, conerrno;
1998 
1999 	file_size = size;
2000 	byte_count = 0;
2001 	if (size != (off_t) -1)
2002 		(void)snprintf(sizebuf, sizeof(sizebuf), " (" LLF " byte%s)",
2003 		    (LLT)size, PLURAL(size));
2004 	else
2005 		sizebuf[0] = '\0';
2006 	if (pdata >= 0) {
2007 		struct sockinet from;
2008 		int s;
2009 		socklen_t fromlen = sizeof(from.su_len);
2010 
2011 		(void) alarm(curclass.timeout);
2012 		s = accept(pdata, (struct sockaddr *)&from.si_su, &fromlen);
2013 		(void) alarm(0);
2014 		if (s < 0) {
2015 			reply(425, "Can't open data connection.");
2016 			(void) close(pdata);
2017 			pdata = -1;
2018 			return (NULL);
2019 		}
2020 		(void) close(pdata);
2021 		pdata = s;
2022 		switch (from.su_family) {
2023 		case AF_INET:
2024 #ifdef IP_TOS
2025 			if (!mapped) {
2026 				tos = IPTOS_THROUGHPUT;
2027 				(void) setsockopt(s, IPPROTO_IP, IP_TOS,
2028 				    (char *)&tos, sizeof(int));
2029 			}
2030 			break;
2031 #endif
2032 		}
2033 		/* Set keepalives on the socket to detect dropped conns. */
2034 #ifdef SO_KEEPALIVE
2035 		keepalive = 1;
2036 		(void) setsockopt(s, SOL_SOCKET, SO_KEEPALIVE,
2037 		    (char *)&keepalive, sizeof(int));
2038 #endif
2039 		reply(150, "Opening %s mode data connection for '%s'%s.",
2040 		     type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
2041 		return (fdopen(pdata, fmode));
2042 	}
2043 	if (data >= 0) {
2044 		reply(125, "Using existing data connection for '%s'%s.",
2045 		    name, sizebuf);
2046 		usedefault = 1;
2047 		return (fdopen(data, fmode));
2048 	}
2049 	if (usedefault)
2050 		data_dest = his_addr;
2051 	usedefault = 1;
2052 	retry = conerrno = 0;
2053 	do {
2054 		file = getdatasock(fmode);
2055 		if (file == NULL) {
2056 			char hbuf[NI_MAXHOST];
2057 			char pbuf[NI_MAXSERV];
2058 
2059 			if (getnameinfo((struct sockaddr *)&data_source.si_su,
2060 			    data_source.su_len, hbuf, sizeof(hbuf), pbuf,
2061 			    sizeof(pbuf), NI_NUMERICHOST | NI_NUMERICSERV))
2062 				strlcpy(hbuf, "?", sizeof(hbuf));
2063 			reply(425, "Can't create data socket (%s,%s): %s.",
2064 			      hbuf, pbuf, strerror(errno));
2065 			return (NULL);
2066 		}
2067 		data = fileno(file);
2068 		conerrno = 0;
2069 		if (connect(data, (struct sockaddr *)&data_dest.si_su,
2070 		    data_dest.su_len) == 0)
2071 			break;
2072 		conerrno = errno;
2073 		(void) fclose(file);
2074 		file = NULL;
2075 		data = -1;
2076 		if (conerrno == EADDRINUSE) {
2077 			sleep((unsigned) swaitint);
2078 			retry += swaitint;
2079 		} else {
2080 			break;
2081 		}
2082 	} while (retry <= swaitmax);
2083 	if (conerrno != 0) {
2084 		perror_reply(425, "Can't build data connection");
2085 		return (NULL);
2086 	}
2087 	reply(150, "Opening %s mode data connection for '%s'%s.",
2088 	     type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
2089 	return (file);
2090 }
2091 
2092 void
closedataconn(FILE * fd)2093 closedataconn(FILE *fd)
2094 {
2095 
2096 	if (fd == NULL)
2097 		return;
2098 	(void)fclose(fd);
2099 	data = -1;
2100 	if (pdata >= 0)
2101 		(void)close(pdata);
2102 	pdata = -1;
2103 }
2104 
2105 int
write_data(int fd,char * buf,size_t size,off_t * bufrem,struct timeval * then,int isdata)2106 write_data(int fd, char *buf, size_t size, off_t *bufrem,
2107     struct timeval *then, int isdata)
2108 {
2109 	struct timeval now, td;
2110 	ssize_t c;
2111 
2112 	while (size > 0) {
2113 		c = size;
2114 		if (curclass.writesize) {
2115 			if (curclass.writesize < c)
2116 				c = curclass.writesize;
2117 		}
2118 		if (curclass.rateget) {
2119 			if (*bufrem < c)
2120 				c = *bufrem;
2121 		}
2122 		(void) alarm(curclass.timeout);
2123 		c = write(fd, buf, c);
2124 		if (c <= 0)
2125 			return (1);
2126 		buf += c;
2127 		size -= c;
2128 		byte_count += c;
2129 		if (isdata) {
2130 			total_data_out += c;
2131 			total_data += c;
2132 		}
2133 		total_bytes_out += c;
2134 		total_bytes += c;
2135 		if (curclass.rateget) {
2136 			*bufrem -= c;
2137 			if (*bufrem == 0) {
2138 				(void)gettimeofday(&now, NULL);
2139 				timersub(&now, then, &td);
2140 				if (td.tv_sec == 0) {
2141 					usleep(1000000 - td.tv_usec);
2142 					(void)gettimeofday(then, NULL);
2143 				} else
2144 					*then = now;
2145 				*bufrem = curclass.rateget;
2146 			}
2147 		}
2148 	}
2149 	return (0);
2150 }
2151 
2152 static enum send_status
send_data_with_read(int filefd,int netfd,const struct stat * st,int isdata)2153 send_data_with_read(int filefd, int netfd, const struct stat *st, int isdata)
2154 {
2155 	struct timeval then;
2156 	off_t bufrem;
2157 	ssize_t readsize;
2158 	char *buf;
2159 	int c, error;
2160 
2161 	if (curclass.readsize > 0)
2162 		readsize = curclass.readsize;
2163 	else
2164 		readsize = st->st_blksize;
2165 	if ((buf = malloc(readsize)) == NULL) {
2166 		perror_reply(451, "Local resource failure: malloc");
2167 		return (SS_NO_TRANSFER);
2168 	}
2169 
2170 	if (curclass.rateget) {
2171 		bufrem = curclass.rateget;
2172 		(void)gettimeofday(&then, NULL);
2173 	} else
2174 		bufrem = readsize;
2175 	for (;;) {
2176 		(void) alarm(curclass.timeout);
2177 		c = read(filefd, buf, readsize);
2178 		if (c == 0)
2179 			error = SS_SUCCESS;
2180 		else if (c < 0)
2181 			error = SS_FILE_ERROR;
2182 		else if (write_data(netfd, buf, c, &bufrem, &then, isdata))
2183 			error = SS_DATA_ERROR;
2184 		else if (urgflag && handleoobcmd())
2185 			error = SS_ABORTED;
2186 		else
2187 			continue;
2188 
2189 		free(buf);
2190 		return (error);
2191 	}
2192 }
2193 
2194 static enum send_status
send_data_with_mmap(int filefd,int netfd,const struct stat * st,int isdata)2195 send_data_with_mmap(int filefd, int netfd, const struct stat *st, int isdata)
2196 {
2197 	struct timeval then;
2198 	off_t bufrem, filesize, off, origoff;
2199 	ssize_t mapsize, winsize;
2200 	int error, sendbufsize, sendlowat;
2201 	void *win;
2202 
2203 	bufrem = 0;
2204 	if (curclass.sendbufsize) {
2205 		sendbufsize = curclass.sendbufsize;
2206 		if (setsockopt(netfd, SOL_SOCKET, SO_SNDBUF,
2207 		    &sendbufsize, sizeof(int)) == -1)
2208 			syslog(LOG_WARNING, "setsockopt(SO_SNDBUF, %d): %m",
2209 			    sendbufsize);
2210 	}
2211 
2212 	if (curclass.sendlowat) {
2213 		sendlowat = curclass.sendlowat;
2214 		if (setsockopt(netfd, SOL_SOCKET, SO_SNDLOWAT,
2215 		    &sendlowat, sizeof(int)) == -1)
2216 			syslog(LOG_WARNING, "setsockopt(SO_SNDLOWAT, %d): %m",
2217 			    sendlowat);
2218 	}
2219 
2220 	winsize = curclass.mmapsize;
2221 	filesize = st->st_size;
2222 	if (ftpd_debug)
2223 		syslog(LOG_INFO, "mmapsize = " LLF ", writesize = " LLF,
2224 		    (LLT)winsize, (LLT)curclass.writesize);
2225 	if (winsize <= 0)
2226 		goto try_read;
2227 
2228 	off = lseek(filefd, (off_t)0, SEEK_CUR);
2229 	if (off == -1)
2230 		goto try_read;
2231 
2232 	origoff = off;
2233 	if (curclass.rateget) {
2234 		bufrem = curclass.rateget;
2235 		(void)gettimeofday(&then, NULL);
2236 	} else
2237 		bufrem = winsize;
2238 	while (1) {
2239 		mapsize = MIN(filesize - off, winsize);
2240 		if (mapsize == 0)
2241 			break;
2242 		win = mmap(NULL, mapsize, PROT_READ,
2243 		    MAP_FILE|MAP_SHARED, filefd, off);
2244 		if (win == MAP_FAILED) {
2245 			if (off == origoff)
2246 				goto try_read;
2247 			return (SS_FILE_ERROR);
2248 		}
2249 #if !defined(__minix)
2250 		(void) madvise(win, mapsize, MADV_SEQUENTIAL);
2251 #endif /* !defined(__minix) */
2252 		error = write_data(netfd, win, mapsize, &bufrem, &then,
2253 		    isdata);
2254 #if !defined(__minix)
2255 		(void) madvise(win, mapsize, MADV_DONTNEED);
2256 #endif /* !defined(__minix) */
2257 		munmap(win, mapsize);
2258 		if (urgflag && handleoobcmd())
2259 			return (SS_ABORTED);
2260 		if (error)
2261 			return (SS_DATA_ERROR);
2262 		off += mapsize;
2263 	}
2264 	return (SS_SUCCESS);
2265 
2266  try_read:
2267 	return (send_data_with_read(filefd, netfd, st, isdata));
2268 }
2269 
2270 /*
2271  * Transfer the contents of "instr" to "outstr" peer using the appropriate
2272  * encapsulation of the data subject to Mode, Structure, and Type.
2273  *
2274  * NB: Form isn't handled.
2275  */
2276 static int
send_data(FILE * instr,FILE * outstr,const struct stat * st,int isdata)2277 send_data(FILE *instr, FILE *outstr, const struct stat *st, int isdata)
2278 {
2279 	int	 c, filefd, netfd, rval;
2280 
2281 	urgflag = 0;
2282 	transflag = 1;
2283 	rval = -1;
2284 
2285 	switch (type) {
2286 
2287 	case TYPE_A:
2288  /* XXXLUKEM: rate limit ascii send (get) */
2289 		(void) alarm(curclass.timeout);
2290 		while ((c = getc(instr)) != EOF) {
2291 			if (urgflag && handleoobcmd())
2292 				goto cleanup_send_data;
2293 			byte_count++;
2294 			if (c == '\n') {
2295 				if (ferror(outstr))
2296 					goto data_err;
2297 				(void) putc('\r', outstr);
2298 				if (isdata) {
2299 					total_data_out++;
2300 					total_data++;
2301 				}
2302 				total_bytes_out++;
2303 				total_bytes++;
2304 			}
2305 			(void) putc(c, outstr);
2306 			if (isdata) {
2307 				total_data_out++;
2308 				total_data++;
2309 			}
2310 			total_bytes_out++;
2311 			total_bytes++;
2312 			if ((byte_count % 4096) == 0)
2313 				(void) alarm(curclass.timeout);
2314 		}
2315 		(void) alarm(0);
2316 		fflush(outstr);
2317 		if (ferror(instr))
2318 			goto file_err;
2319 		if (ferror(outstr))
2320 			goto data_err;
2321 		rval = 0;
2322 		goto cleanup_send_data;
2323 
2324 	case TYPE_I:
2325 	case TYPE_L:
2326 		filefd = fileno(instr);
2327 		netfd = fileno(outstr);
2328 		switch (send_data_with_mmap(filefd, netfd, st, isdata)) {
2329 
2330 		case SS_SUCCESS:
2331 			break;
2332 
2333 		case SS_ABORTED:
2334 		case SS_NO_TRANSFER:
2335 			goto cleanup_send_data;
2336 
2337 		case SS_FILE_ERROR:
2338 			goto file_err;
2339 
2340 		case SS_DATA_ERROR:
2341 			goto data_err;
2342 		}
2343 		rval = 0;
2344 		goto cleanup_send_data;
2345 
2346 	default:
2347 		reply(550, "Unimplemented TYPE %d in send_data", type);
2348 		goto cleanup_send_data;
2349 	}
2350 
2351  data_err:
2352 	(void) alarm(0);
2353 	perror_reply(426, "Data connection");
2354 	goto cleanup_send_data;
2355 
2356  file_err:
2357 	(void) alarm(0);
2358 	perror_reply(551, "Error on input file");
2359 	goto cleanup_send_data;
2360 
2361  cleanup_send_data:
2362 	(void) alarm(0);
2363 	transflag = 0;
2364 	urgflag = 0;
2365 	if (isdata) {
2366 		total_files_out++;
2367 		total_files++;
2368 	}
2369 	total_xfers_out++;
2370 	total_xfers++;
2371 	return (rval);
2372 }
2373 
2374 /*
2375  * Transfer data from peer to "outstr" using the appropriate encapulation of
2376  * the data subject to Mode, Structure, and Type.
2377  *
2378  * N.B.: Form isn't handled.
2379  */
2380 static int
receive_data(FILE * instr,FILE * outstr)2381 receive_data(FILE *instr, FILE *outstr)
2382 {
2383 	int	c, netfd, filefd, rval;
2384 	int	volatile bare_lfs;
2385 	off_t	byteswritten;
2386 	char	*buf;
2387 	ssize_t	readsize;
2388 	struct sigaction sa, sa_saved;
2389 	struct stat st;
2390 
2391 	memset(&sa, 0, sizeof(sa));
2392 	sigfillset(&sa.sa_mask);
2393 	sa.sa_flags = SA_RESTART;
2394 	sa.sa_handler = lostconn;
2395 	(void) sigaction(SIGALRM, &sa, &sa_saved);
2396 
2397 	bare_lfs = 0;
2398 	urgflag = 0;
2399 	transflag = 1;
2400 	rval = -1;
2401 	byteswritten = 0;
2402 	buf = NULL;
2403 
2404 #define FILESIZECHECK(x) \
2405 			do { \
2406 				if (curclass.maxfilesize != -1 && \
2407 				    (x) > curclass.maxfilesize) { \
2408 					errno = EFBIG; \
2409 					goto file_err; \
2410 				} \
2411 			} while (0)
2412 
2413 	switch (type) {
2414 
2415 	case TYPE_I:
2416 	case TYPE_L:
2417 		netfd = fileno(instr);
2418 		filefd = fileno(outstr);
2419 		(void) alarm(curclass.timeout);
2420 		if (curclass.readsize)
2421 			readsize = curclass.readsize;
2422 		else if (fstat(filefd, &st) != -1)
2423 			readsize = (ssize_t)st.st_blksize;
2424 		else
2425 			readsize = BUFSIZ;
2426 		if ((buf = malloc(readsize)) == NULL) {
2427 			perror_reply(451, "Local resource failure: malloc");
2428 			goto cleanup_recv_data;
2429 		}
2430 		if (curclass.rateput) {
2431 			while (1) {
2432 				int d;
2433 				struct timeval then, now, td;
2434 				off_t bufrem;
2435 
2436 				(void)gettimeofday(&then, NULL);
2437 				errno = c = d = 0;
2438 				for (bufrem = curclass.rateput; bufrem > 0; ) {
2439 					if ((c = read(netfd, buf,
2440 					    MIN(readsize, bufrem))) <= 0)
2441 						goto recvdone;
2442 					if (urgflag && handleoobcmd())
2443 						goto cleanup_recv_data;
2444 					FILESIZECHECK(byte_count + c);
2445 					if ((d = write(filefd, buf, c)) != c)
2446 						goto file_err;
2447 					(void) alarm(curclass.timeout);
2448 					bufrem -= c;
2449 					byte_count += c;
2450 					total_data_in += c;
2451 					total_data += c;
2452 					total_bytes_in += c;
2453 					total_bytes += c;
2454 				}
2455 				(void)gettimeofday(&now, NULL);
2456 				timersub(&now, &then, &td);
2457 				if (td.tv_sec == 0)
2458 					usleep(1000000 - td.tv_usec);
2459 			}
2460 		} else {
2461 			while ((c = read(netfd, buf, readsize)) > 0) {
2462 				if (urgflag && handleoobcmd())
2463 					goto cleanup_recv_data;
2464 				FILESIZECHECK(byte_count + c);
2465 				if (write(filefd, buf, c) != c)
2466 					goto file_err;
2467 				(void) alarm(curclass.timeout);
2468 				byte_count += c;
2469 				total_data_in += c;
2470 				total_data += c;
2471 				total_bytes_in += c;
2472 				total_bytes += c;
2473 			}
2474 		}
2475  recvdone:
2476 		if (c < 0)
2477 			goto data_err;
2478 		rval = 0;
2479 		goto cleanup_recv_data;
2480 
2481 	case TYPE_E:
2482 		reply(553, "TYPE E not implemented.");
2483 		goto cleanup_recv_data;
2484 
2485 	case TYPE_A:
2486 		(void) alarm(curclass.timeout);
2487  /* XXXLUKEM: rate limit ascii receive (put) */
2488 		while ((c = getc(instr)) != EOF) {
2489 			if (urgflag && handleoobcmd())
2490 				goto cleanup_recv_data;
2491 			byte_count++;
2492 			total_data_in++;
2493 			total_data++;
2494 			total_bytes_in++;
2495 			total_bytes++;
2496 			if ((byte_count % 4096) == 0)
2497 				(void) alarm(curclass.timeout);
2498 			if (c == '\n')
2499 				bare_lfs++;
2500 			while (c == '\r') {
2501 				if (ferror(outstr))
2502 					goto data_err;
2503 				if ((c = getc(instr)) != '\n') {
2504 					byte_count++;
2505 					total_data_in++;
2506 					total_data++;
2507 					total_bytes_in++;
2508 					total_bytes++;
2509 					if ((byte_count % 4096) == 0)
2510 						(void) alarm(curclass.timeout);
2511 					byteswritten++;
2512 					FILESIZECHECK(byteswritten);
2513 					(void) putc ('\r', outstr);
2514 					if (c == '\0' || c == EOF)
2515 						goto contin2;
2516 				}
2517 			}
2518 			byteswritten++;
2519 			FILESIZECHECK(byteswritten);
2520 			(void) putc(c, outstr);
2521  contin2:	;
2522 		}
2523 		(void) alarm(0);
2524 		fflush(outstr);
2525 		if (ferror(instr))
2526 			goto data_err;
2527 		if (ferror(outstr))
2528 			goto file_err;
2529 		if (bare_lfs) {
2530 			reply(-226,
2531 			    "WARNING! %d bare linefeeds received in ASCII mode",
2532 			    bare_lfs);
2533 			reply(0, "File may not have transferred correctly.");
2534 		}
2535 		rval = 0;
2536 		goto cleanup_recv_data;
2537 
2538 	default:
2539 		reply(550, "Unimplemented TYPE %d in receive_data", type);
2540 		goto cleanup_recv_data;
2541 	}
2542 #undef FILESIZECHECK
2543 
2544  data_err:
2545 	(void) alarm(0);
2546 	perror_reply(426, "Data Connection");
2547 	goto cleanup_recv_data;
2548 
2549  file_err:
2550 	(void) alarm(0);
2551 	perror_reply(452, "Error writing file");
2552 	goto cleanup_recv_data;
2553 
2554  cleanup_recv_data:
2555 	(void) alarm(0);
2556 	(void) sigaction(SIGALRM, &sa_saved, NULL);
2557 	if (buf)
2558 		free(buf);
2559 	transflag = 0;
2560 	urgflag = 0;
2561 	total_files_in++;
2562 	total_files++;
2563 	total_xfers_in++;
2564 	total_xfers++;
2565 	return (rval);
2566 }
2567 
2568 void
statcmd(void)2569 statcmd(void)
2570 {
2571 	struct sockinet *su = NULL;
2572 	static char hbuf[NI_MAXHOST], sbuf[NI_MAXSERV];
2573 	unsigned char *a, *p;
2574 	int ispassive, af;
2575 	off_t otbi, otbo, otb;
2576 
2577 	a = p = NULL;
2578 
2579 	reply(-211, "%s FTP server status:", hostname);
2580 	reply(0, "Version: %s", EMPTYSTR(version) ? "<suppressed>" : version);
2581 	hbuf[0] = '\0';
2582 	if (!getnameinfo((struct sockaddr *)&his_addr.si_su, his_addr.su_len,
2583 			hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST)
2584 	    && strcmp(remotehost, hbuf) != 0)
2585 		reply(0, "Connected to %s (%s)", remotehost, hbuf);
2586 	else
2587 		reply(0, "Connected to %s", remotehost);
2588 
2589 	if (logged_in) {
2590 		if (curclass.type == CLASS_GUEST)
2591 			reply(0, "Logged in anonymously");
2592 		else
2593 			reply(0, "Logged in as %s%s", pw->pw_name,
2594 			    curclass.type == CLASS_CHROOT ? " (chroot)" : "");
2595 	} else if (askpasswd)
2596 		reply(0, "Waiting for password");
2597 	else
2598 		reply(0, "Waiting for user name");
2599 	cprintf(stdout, "    TYPE: %s", typenames[type]);
2600 	if (type == TYPE_A || type == TYPE_E)
2601 		cprintf(stdout, ", FORM: %s", formnames[form]);
2602 	if (type == TYPE_L) {
2603 #if NBBY == 8
2604 		cprintf(stdout, " %d", NBBY);
2605 #else
2606 			/* XXX: `bytesize' needs to be defined in this case */
2607 		cprintf(stdout, " %d", bytesize);
2608 #endif
2609 	}
2610 	cprintf(stdout, "; STRUcture: %s; transfer MODE: %s\r\n",
2611 	    strunames[stru], modenames[mode]);
2612 	ispassive = 0;
2613 	if (data != -1) {
2614 		reply(0, "Data connection open");
2615 		su = NULL;
2616 	} else if (pdata != -1) {
2617 		reply(0, "in Passive mode");
2618 		if (curclass.advertise.su_len != 0)
2619 			su = &curclass.advertise;
2620 		else
2621 			su = &pasv_addr;
2622 		ispassive = 1;
2623 		goto printaddr;
2624 	} else if (usedefault == 0) {
2625 		su = (struct sockinet *)&data_dest;
2626 
2627 		if (epsvall) {
2628 			reply(0, "EPSV only mode (EPSV ALL)");
2629 			goto epsvonly;
2630 		}
2631  printaddr:
2632 							/* PASV/PORT */
2633 		if (su->su_family == AF_INET) {
2634 			a = (unsigned char *) &su->su_addr;
2635 			p = (unsigned char *) &su->su_port;
2636 #define UC(b) (((int) b) & 0xff)
2637 			reply(0, "%s (%d,%d,%d,%d,%d,%d)",
2638 				ispassive ? "PASV" : "PORT" ,
2639 				UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
2640 				UC(p[0]), UC(p[1]));
2641 		}
2642 
2643 							/* LPSV/LPRT */
2644 	    {
2645 		int alen, i;
2646 
2647 		alen = 0;
2648 		switch (su->su_family) {
2649 		case AF_INET:
2650 			a = (unsigned char *) &su->su_addr;
2651 			p = (unsigned char *) &su->su_port;
2652 			alen = sizeof(su->su_addr);
2653 			af = 4;
2654 			break;
2655 #ifdef INET6
2656 		case AF_INET6:
2657 			a = (unsigned char *) &su->su_6addr;
2658 			p = (unsigned char *) &su->su_port;
2659 			alen = sizeof(su->su_6addr);
2660 			af = 6;
2661 			break;
2662 #endif
2663 		default:
2664 			af = 0;
2665 			break;
2666 		}
2667 		if (af) {
2668 			cprintf(stdout, "    %s (%d,%d",
2669 			    ispassive ? "LPSV" : "LPRT", af, alen);
2670 			for (i = 0; i < alen; i++)
2671 				cprintf(stdout, ",%d", UC(a[i]));
2672 			cprintf(stdout, ",%d,%d,%d)\r\n",
2673 			    2, UC(p[0]), UC(p[1]));
2674 #undef UC
2675 		}
2676 	    }
2677 
2678 		/* EPRT/EPSV */
2679  epsvonly:
2680 		af = af2epsvproto(su->su_family);
2681 		hbuf[0] = '\0';
2682 		if (af > 0) {
2683 			struct sockinet tmp;
2684 
2685 			tmp = *su;
2686 #ifdef INET6
2687 			if (tmp.su_family == AF_INET6)
2688 				tmp.su_scope_id = 0;
2689 #endif
2690 			if (getnameinfo((struct sockaddr *)&tmp.si_su,
2691 			    tmp.su_len, hbuf, sizeof(hbuf), sbuf, sizeof(sbuf),
2692 			    NI_NUMERICHOST | NI_NUMERICSERV) == 0)
2693 				reply(0, "%s (|%d|%s|%s|)",
2694 				    ispassive ? "EPSV" : "EPRT",
2695 				    af, hbuf, sbuf);
2696 		}
2697 	} else
2698 		reply(0, "No data connection");
2699 
2700 	if (logged_in) {
2701 		reply(0,
2702 		    "Data sent:        " LLF " byte%s in " LLF " file%s",
2703 		    (LLT)total_data_out, PLURAL(total_data_out),
2704 		    (LLT)total_files_out, PLURAL(total_files_out));
2705 		reply(0,
2706 		    "Data received:    " LLF " byte%s in " LLF " file%s",
2707 		    (LLT)total_data_in, PLURAL(total_data_in),
2708 		    (LLT)total_files_in, PLURAL(total_files_in));
2709 		reply(0,
2710 		    "Total data:       " LLF " byte%s in " LLF " file%s",
2711 		    (LLT)total_data, PLURAL(total_data),
2712 		    (LLT)total_files, PLURAL(total_files));
2713 	}
2714 	otbi = total_bytes_in;
2715 	otbo = total_bytes_out;
2716 	otb = total_bytes;
2717 	reply(0, "Traffic sent:     " LLF " byte%s in " LLF " transfer%s",
2718 	    (LLT)otbo, PLURAL(otbo),
2719 	    (LLT)total_xfers_out, PLURAL(total_xfers_out));
2720 	reply(0, "Traffic received: " LLF " byte%s in " LLF " transfer%s",
2721 	    (LLT)otbi, PLURAL(otbi),
2722 	    (LLT)total_xfers_in, PLURAL(total_xfers_in));
2723 	reply(0, "Total traffic:    " LLF " byte%s in " LLF " transfer%s",
2724 	    (LLT)otb, PLURAL(otb),
2725 	    (LLT)total_xfers, PLURAL(total_xfers));
2726 
2727 	if (logged_in && !CURCLASS_FLAGS_ISSET(private)) {
2728 		struct ftpconv *cp;
2729 
2730 		reply(0, "%s", "");
2731 		reply(0, "Class: %s, type: %s",
2732 		    curclass.classname, CURCLASSTYPE);
2733 		reply(0, "Check PORT/LPRT commands: %sabled",
2734 		    CURCLASS_FLAGS_ISSET(checkportcmd) ? "en" : "dis");
2735 		if (! EMPTYSTR(curclass.display))
2736 			reply(0, "Display file: %s", curclass.display);
2737 		if (! EMPTYSTR(curclass.notify))
2738 			reply(0, "Notify fileglob: %s", curclass.notify);
2739 		reply(0, "Idle timeout: " LLF ", maximum timeout: " LLF,
2740 		    (LLT)curclass.timeout, (LLT)curclass.maxtimeout);
2741 		reply(0, "Current connections: %d", connections);
2742 		if (curclass.limit == -1)
2743 			reply(0, "Maximum connections: unlimited");
2744 		else
2745 			reply(0, "Maximum connections: " LLF,
2746 			    (LLT)curclass.limit);
2747 		if (curclass.limitfile)
2748 			reply(0, "Connection limit exceeded message file: %s",
2749 			    conffilename(curclass.limitfile));
2750 		if (! EMPTYSTR(curclass.chroot))
2751 			reply(0, "Chroot format: %s", curclass.chroot);
2752 		reply(0, "Deny bad ftpusers(5) quickly: %sabled",
2753 		    CURCLASS_FLAGS_ISSET(denyquick) ? "en" : "dis");
2754 		if (! EMPTYSTR(curclass.homedir))
2755 			reply(0, "Homedir format: %s", curclass.homedir);
2756 		if (curclass.maxfilesize == -1)
2757 			reply(0, "Maximum file size: unlimited");
2758 		else
2759 			reply(0, "Maximum file size: " LLF,
2760 			    (LLT)curclass.maxfilesize);
2761 		if (! EMPTYSTR(curclass.motd))
2762 			reply(0, "MotD file: %s", conffilename(curclass.motd));
2763 		reply(0,
2764 	    "Modify commands (CHMOD, DELE, MKD, RMD, RNFR, UMASK): %sabled",
2765 		    CURCLASS_FLAGS_ISSET(modify) ? "en" : "dis");
2766 		reply(0, "Upload commands (APPE, STOR, STOU): %sabled",
2767 		    CURCLASS_FLAGS_ISSET(upload) ? "en" : "dis");
2768 		reply(0, "Sanitize file names: %sabled",
2769 		    CURCLASS_FLAGS_ISSET(sanenames) ? "en" : "dis");
2770 		reply(0, "PASV/LPSV/EPSV connections: %sabled",
2771 		    CURCLASS_FLAGS_ISSET(passive) ? "en" : "dis");
2772 		if (curclass.advertise.su_len != 0) {
2773 			char buf[50];	/* big enough for IPv6 address */
2774 			const char *bp;
2775 
2776 			bp = inet_ntop(curclass.advertise.su_family,
2777 			    (void *)&curclass.advertise.su_addr,
2778 			    buf, sizeof(buf));
2779 			if (bp != NULL)
2780 				reply(0, "PASV advertise address: %s", bp);
2781 		}
2782 		if (curclass.portmin && curclass.portmax)
2783 			reply(0, "PASV port range: " LLF " - " LLF,
2784 			    (LLT)curclass.portmin, (LLT)curclass.portmax);
2785 		if (curclass.rateget)
2786 			reply(0, "Rate get limit: " LLF " bytes/sec",
2787 			    (LLT)curclass.rateget);
2788 		else
2789 			reply(0, "Rate get limit: disabled");
2790 		if (curclass.rateput)
2791 			reply(0, "Rate put limit: " LLF " bytes/sec",
2792 			    (LLT)curclass.rateput);
2793 		else
2794 			reply(0, "Rate put limit: disabled");
2795 		if (curclass.mmapsize)
2796 			reply(0, "Mmap size: " LLF, (LLT)curclass.mmapsize);
2797 		else
2798 			reply(0, "Mmap size: disabled");
2799 		if (curclass.readsize)
2800 			reply(0, "Read size: " LLF, (LLT)curclass.readsize);
2801 		else
2802 			reply(0, "Read size: default");
2803 		if (curclass.writesize)
2804 			reply(0, "Write size: " LLF, (LLT)curclass.writesize);
2805 		else
2806 			reply(0, "Write size: default");
2807 		if (curclass.recvbufsize)
2808 			reply(0, "Receive buffer size: " LLF,
2809 			    (LLT)curclass.recvbufsize);
2810 		else
2811 			reply(0, "Receive buffer size: default");
2812 		if (curclass.sendbufsize)
2813 			reply(0, "Send buffer size: " LLF,
2814 			    (LLT)curclass.sendbufsize);
2815 		else
2816 			reply(0, "Send buffer size: default");
2817 		if (curclass.sendlowat)
2818 			reply(0, "Send low water mark: " LLF,
2819 			    (LLT)curclass.sendlowat);
2820 		else
2821 			reply(0, "Send low water mark: default");
2822 		reply(0, "Umask: %.04o", curclass.umask);
2823 		for (cp = curclass.conversions; cp != NULL; cp=cp->next) {
2824 			if (cp->suffix == NULL || cp->types == NULL ||
2825 			    cp->command == NULL)
2826 				continue;
2827 			reply(0, "Conversion: %s [%s] disable: %s, command: %s",
2828 			    cp->suffix, cp->types, cp->disable, cp->command);
2829 		}
2830 	}
2831 
2832 	reply(211, "End of status");
2833 }
2834 
2835 void
fatal(const char * s)2836 fatal(const char *s)
2837 {
2838 
2839 	reply(451, "Error in server: %s\n", s);
2840 	reply(221, "Closing connection due to server error.");
2841 	dologout(0);
2842 	/* NOTREACHED */
2843 }
2844 
2845 /*
2846  * reply() --
2847  *	depending on the value of n, display fmt with a trailing CRLF and
2848  *	prefix of:
2849  *	n < -1		prefix the message with abs(n) + "-"	(initial line)
2850  *	n == 0		prefix the message with 4 spaces	(middle lines)
2851  *	n >  0		prefix the message with n + " "		(final line)
2852  */
2853 void
reply(int n,const char * fmt,...)2854 reply(int n, const char *fmt, ...)
2855 {
2856 	char	msg[MAXPATHLEN * 2 + 100];
2857 	size_t	b;
2858 	va_list	ap;
2859 
2860 	if (n == 0)
2861 		b = snprintf(msg, sizeof(msg), "    ");
2862 	else if (n < 0)
2863 		b = snprintf(msg, sizeof(msg), "%d-", -n);
2864 	else
2865 		b = snprintf(msg, sizeof(msg), "%d ", n);
2866 	va_start(ap, fmt);
2867 	vsnprintf(msg + b, sizeof(msg) - b, fmt, ap);
2868 	va_end(ap);
2869 	cprintf(stdout, "%s\r\n", msg);
2870 	(void)fflush(stdout);
2871 	if (ftpd_debug)
2872 		syslog(LOG_DEBUG, "<--- %s", msg);
2873 }
2874 
2875 static void
logremotehost(struct sockinet * who)2876 logremotehost(struct sockinet *who)
2877 {
2878 
2879 #if defined(HAVE_SOCKADDR_SNPRINTF)
2880 	char abuf[BUFSIZ];
2881 #endif
2882 
2883 	struct sockaddr *sa = (struct sockaddr *)&who->si_su;
2884 	if (getnameinfo(sa, who->su_len, remotehost, sizeof(remotehost), NULL,
2885 	    0, getnameopts))
2886 		strlcpy(remotehost, "?", sizeof(remotehost));
2887 #if defined(HAVE_SOCKADDR_SNPRINTF)
2888 	sockaddr_snprintf(abuf, sizeof(abuf), "%a", sa);
2889 	snprintf(remoteloghost, sizeof(remoteloghost), "%s(%s)", remotehost,
2890 	    abuf);
2891 #else
2892 	strlcpy(remoteloghost, remotehost, sizeof(remoteloghost));
2893 #endif
2894 
2895 #if defined(HAVE_SETPROCTITLE)
2896 	snprintf(proctitle, sizeof(proctitle), "%s: connected", remotehost);
2897 	setproctitle("%s", proctitle);
2898 #endif /* defined(HAVE_SETPROCTITLE) */
2899 	if (logging)
2900 		syslog(LOG_INFO, "connection from %s to %s",
2901 		    remoteloghost, hostname);
2902 }
2903 
2904 /*
2905  * Record logout in wtmp file and exit with supplied status.
2906  * NOTE: because this is called from signal handlers it cannot
2907  *       use stdio (or call other functions that use stdio).
2908  */
2909 void
dologout(int status)2910 dologout(int status)
2911 {
2912 	/*
2913 	* Prevent reception of SIGURG from resulting in a resumption
2914 	* back to the main program loop.
2915 	*/
2916 	transflag = 0;
2917 	logout_utmp();
2918 	if (logged_in) {
2919 #ifdef KERBEROS
2920 		if (!notickets && krbtkfile_env)
2921 			unlink(krbtkfile_env);
2922 #endif
2923 	}
2924 	/* beware of flushing buffers after a SIGPIPE */
2925 	if (xferlogfd != -1)
2926 		close(xferlogfd);
2927 	_exit(status);
2928 }
2929 
2930 void
abor(void)2931 abor(void)
2932 {
2933 
2934 	if (!transflag)
2935 		return;
2936 	tmpline[0] = '\0';
2937 	is_oob = 0;
2938 	reply(426, "Transfer aborted. Data connection closed.");
2939 	reply(226, "Abort successful");
2940 	transflag = 0;		/* flag that the transfer has aborted */
2941 }
2942 
2943 void
statxfer(void)2944 statxfer(void)
2945 {
2946 
2947 	if (!transflag)
2948 		return;
2949 	tmpline[0] = '\0';
2950 	is_oob = 0;
2951 	if (file_size != (off_t) -1)
2952 		reply(213,
2953 		    "Status: " LLF " of " LLF " byte%s transferred",
2954 		    (LLT)byte_count, (LLT)file_size,
2955 		    PLURAL(byte_count));
2956 	else
2957 		reply(213, "Status: " LLF " byte%s transferred",
2958 		    (LLT)byte_count, PLURAL(byte_count));
2959 }
2960 
2961 /*
2962  * Call when urgflag != 0 to handle Out Of Band commands.
2963  * Returns non zero if the OOB command aborted the transfer
2964  * by setting transflag to 0. (c.f., "ABOR").
2965  */
2966 static int
handleoobcmd(void)2967 handleoobcmd(void)
2968 {
2969 	char *cp;
2970 	int ret;
2971 
2972 	if (!urgflag)
2973 		return (0);
2974 	urgflag = 0;
2975 	/* only process if transfer occurring */
2976 	if (!transflag)
2977 		return (0);
2978 	cp = tmpline;
2979 	ret = get_line(cp, sizeof(tmpline)-1, stdin);
2980 	if (ret == -1) {
2981 		reply(221, "You could at least say goodbye.");
2982 		dologout(0);
2983 	} else if (ret == -2) {
2984 		/* Ignore truncated command */
2985 		/* XXX: abort xfer with "500 command too long", & return 1 ? */
2986 		return 0;
2987 	}
2988 		/*
2989 		 * Manually parse OOB commands, because we can't
2990 		 * recursively call the yacc parser...
2991 		 */
2992 	if (strcasecmp(cp, "ABOR\r\n") == 0) {
2993 		abor();
2994 	} else if (strcasecmp(cp, "STAT\r\n") == 0) {
2995 		statxfer();
2996 	} else {
2997 		/* XXX: error with "500 unknown command" ? */
2998 	}
2999 	return (transflag == 0);
3000 }
3001 
3002 static int
bind_pasv_addr(void)3003 bind_pasv_addr(void)
3004 {
3005 	static int passiveport;
3006 	int port, len;
3007 
3008 	len = pasv_addr.su_len;
3009 	if (curclass.portmin == 0 && curclass.portmax == 0) {
3010 		pasv_addr.su_port = 0;
3011 		return (bind(pdata, (struct sockaddr *)&pasv_addr.si_su, len));
3012 	}
3013 
3014 	if (passiveport == 0) {
3015 		srand(getpid());
3016 		passiveport = rand() % (curclass.portmax - curclass.portmin)
3017 		    + curclass.portmin;
3018 	}
3019 
3020 	port = passiveport;
3021 	while (1) {
3022 		port++;
3023 		if (port > curclass.portmax)
3024 			port = curclass.portmin;
3025 		else if (port == passiveport) {
3026 			errno = EAGAIN;
3027 			return (-1);
3028 		}
3029 		pasv_addr.su_port = htons(port);
3030 		if (bind(pdata, (struct sockaddr *)&pasv_addr.si_su, len) == 0)
3031 			break;
3032 		if (errno != EADDRINUSE)
3033 			return (-1);
3034 	}
3035 	passiveport = port;
3036 	return (0);
3037 }
3038 
3039 /*
3040  * Note: a response of 425 is not mentioned as a possible response to
3041  *	the PASV command in RFC959. However, it has been blessed as
3042  *	a legitimate response by Jon Postel in a telephone conversation
3043  *	with Rick Adams on 25 Jan 89.
3044  */
3045 void
passive(void)3046 passive(void)
3047 {
3048 	socklen_t len;
3049 	int recvbufsize;
3050 	char *p, *a;
3051 
3052 	if (pdata >= 0)
3053 		close(pdata);
3054 	pdata = socket(AF_INET, SOCK_STREAM, 0);
3055 	if (pdata < 0 || !logged_in) {
3056 		perror_reply(425, "Can't open passive connection");
3057 		return;
3058 	}
3059 	pasv_addr = ctrl_addr;
3060 
3061 	if (bind_pasv_addr() < 0)
3062 		goto pasv_error;
3063 	len = pasv_addr.su_len;
3064 	if (getsockname(pdata, (struct sockaddr *) &pasv_addr.si_su, &len) < 0)
3065 		goto pasv_error;
3066 	pasv_addr.su_len = len;
3067 	if (curclass.recvbufsize) {
3068 		recvbufsize = curclass.recvbufsize;
3069 		if (setsockopt(pdata, SOL_SOCKET, SO_RCVBUF, &recvbufsize,
3070 			       sizeof(int)) == -1)
3071 			syslog(LOG_WARNING, "setsockopt(SO_RCVBUF, %d): %m",
3072 			       recvbufsize);
3073 	}
3074 	if (listen(pdata, 1) < 0)
3075 		goto pasv_error;
3076 	if (curclass.advertise.su_len != 0)
3077 		a = (char *) &curclass.advertise.su_addr;
3078 	else
3079 		a = (char *) &pasv_addr.su_addr;
3080 	p = (char *) &pasv_addr.su_port;
3081 
3082 #define UC(b) (((int) b) & 0xff)
3083 
3084 	reply(227, "Entering Passive Mode (%d,%d,%d,%d,%d,%d)", UC(a[0]),
3085 		UC(a[1]), UC(a[2]), UC(a[3]), UC(p[0]), UC(p[1]));
3086 	return;
3087 
3088  pasv_error:
3089 	(void) close(pdata);
3090 	pdata = -1;
3091 	perror_reply(425, "Can't open passive connection");
3092 	return;
3093 }
3094 
3095 /*
3096  * convert protocol identifier to/from AF
3097  */
3098 int
lpsvproto2af(int proto)3099 lpsvproto2af(int proto)
3100 {
3101 
3102 	switch (proto) {
3103 	case 4:
3104 		return AF_INET;
3105 #ifdef INET6
3106 	case 6:
3107 		return AF_INET6;
3108 #endif
3109 	default:
3110 		return -1;
3111 	}
3112 }
3113 
3114 int
af2lpsvproto(int af)3115 af2lpsvproto(int af)
3116 {
3117 
3118 	switch (af) {
3119 	case AF_INET:
3120 		return 4;
3121 #ifdef INET6
3122 	case AF_INET6:
3123 		return 6;
3124 #endif
3125 	default:
3126 		return -1;
3127 	}
3128 }
3129 
3130 int
epsvproto2af(int proto)3131 epsvproto2af(int proto)
3132 {
3133 
3134 	switch (proto) {
3135 	case 1:
3136 		return AF_INET;
3137 #ifdef INET6
3138 	case 2:
3139 		return AF_INET6;
3140 #endif
3141 	default:
3142 		return -1;
3143 	}
3144 }
3145 
3146 int
af2epsvproto(int af)3147 af2epsvproto(int af)
3148 {
3149 
3150 	switch (af) {
3151 	case AF_INET:
3152 		return 1;
3153 #ifdef INET6
3154 	case AF_INET6:
3155 		return 2;
3156 #endif
3157 	default:
3158 		return -1;
3159 	}
3160 }
3161 
3162 /*
3163  * 228 Entering Long Passive Mode (af, hal, h1, h2, h3,..., pal, p1, p2...)
3164  * 229 Entering Extended Passive Mode (|||port|)
3165  */
3166 void
long_passive(const char * cmd,int pf)3167 long_passive(const char *cmd, int pf)
3168 {
3169 	socklen_t len;
3170 	char *p, *a;
3171 
3172 	if (!logged_in) {
3173 		syslog(LOG_NOTICE, "long passive but not logged in");
3174 		reply(503, "Login with USER first.");
3175 		return;
3176 	}
3177 
3178 	if (pf != PF_UNSPEC && ctrl_addr.su_family != pf) {
3179 		/*
3180 		 * XXX: only EPRT/EPSV ready clients will understand this
3181 		 */
3182 		if (strcmp(cmd, "EPSV") != 0)
3183 			reply(501, "Network protocol mismatch"); /*XXX*/
3184 		else
3185 			epsv_protounsupp("Network protocol mismatch");
3186 
3187 		return;
3188 	}
3189 
3190 	if (pdata >= 0)
3191 		close(pdata);
3192 	pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
3193 	if (pdata < 0) {
3194 		perror_reply(425, "Can't open passive connection");
3195 		return;
3196 	}
3197 	pasv_addr = ctrl_addr;
3198 	if (bind_pasv_addr() < 0)
3199 		goto pasv_error;
3200 	len = pasv_addr.su_len;
3201 	if (getsockname(pdata, (struct sockaddr *) &pasv_addr.si_su, &len) < 0)
3202 		goto pasv_error;
3203 	pasv_addr.su_len = len;
3204 	if (listen(pdata, 1) < 0)
3205 		goto pasv_error;
3206 	p = (char *) &pasv_addr.su_port;
3207 
3208 #define UC(b) (((int) b) & 0xff)
3209 
3210 	if (strcmp(cmd, "LPSV") == 0) {
3211 		struct sockinet *advert;
3212 
3213 		if (curclass.advertise.su_len != 0)
3214 			advert = &curclass.advertise;
3215 		else
3216 			advert = &pasv_addr;
3217 		switch (advert->su_family) {
3218 		case AF_INET:
3219 			a = (char *) &advert->su_addr;
3220 			reply(228,
3221     "Entering Long Passive Mode (%d,%d,%d,%d,%d,%d,%d,%d,%d)",
3222 				4, 4, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
3223 				2, UC(p[0]), UC(p[1]));
3224 			return;
3225 #ifdef INET6
3226 		case AF_INET6:
3227 			a = (char *) &advert->su_6addr;
3228 			reply(228,
3229     "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)",
3230 				6, 16,
3231 				UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
3232 				UC(a[4]), UC(a[5]), UC(a[6]), UC(a[7]),
3233 				UC(a[8]), UC(a[9]), UC(a[10]), UC(a[11]),
3234 				UC(a[12]), UC(a[13]), UC(a[14]), UC(a[15]),
3235 				2, UC(p[0]), UC(p[1]));
3236 			return;
3237 #endif
3238 		}
3239 #undef UC
3240 	} else if (strcmp(cmd, "EPSV") == 0) {
3241 		switch (pasv_addr.su_family) {
3242 		case AF_INET:
3243 #ifdef INET6
3244 		case AF_INET6:
3245 #endif
3246 			reply(229, "Entering Extended Passive Mode (|||%d|)",
3247 			    ntohs(pasv_addr.su_port));
3248 			return;
3249 		}
3250 	} else {
3251 		/* more proper error code? */
3252 	}
3253 
3254  pasv_error:
3255 	(void) close(pdata);
3256 	pdata = -1;
3257 	perror_reply(425, "Can't open passive connection");
3258 	return;
3259 }
3260 
3261 int
extended_port(const char * arg)3262 extended_port(const char *arg)
3263 {
3264 	char *tmp = NULL;
3265 	char *result[3];
3266 	char *p, *q;
3267 	char delim;
3268 	struct addrinfo hints;
3269 	struct addrinfo *res = NULL;
3270 	int i;
3271 	unsigned long proto;
3272 
3273 	tmp = ftpd_strdup(arg);
3274 	p = tmp;
3275 	delim = p[0];
3276 	p++;
3277 	memset(result, 0, sizeof(result));
3278 	for (i = 0; i < 3; i++) {
3279 		q = strchr(p, delim);
3280 		if (!q || *q != delim)
3281 			goto parsefail;
3282 		*q++ = '\0';
3283 		result[i] = p;
3284 		p = q;
3285 	}
3286 
3287 			/* some more sanity checks */
3288 	errno = 0;
3289 	p = NULL;
3290 	(void)strtoul(result[2], &p, 10);
3291 	if (errno || !*result[2] || *p)
3292 		goto parsefail;
3293 	errno = 0;
3294 	p = NULL;
3295 	proto = strtoul(result[0], &p, 10);
3296 	if (errno || !*result[0] || *p)
3297 		goto protounsupp;
3298 
3299 	memset(&hints, 0, sizeof(hints));
3300 	hints.ai_family = epsvproto2af((int)proto);
3301 	if (hints.ai_family < 0)
3302 		goto protounsupp;
3303 	hints.ai_socktype = SOCK_STREAM;
3304 	hints.ai_flags = AI_NUMERICHOST;
3305 	if (getaddrinfo(result[1], result[2], &hints, &res))
3306 		goto parsefail;
3307 	if (res->ai_next)
3308 		goto parsefail;
3309 	if (sizeof(data_dest) < res->ai_addrlen)
3310 		goto parsefail;
3311 	memcpy(&data_dest.si_su, res->ai_addr, res->ai_addrlen);
3312 	data_dest.su_len = res->ai_addrlen;
3313 #ifdef INET6
3314 	if (his_addr.su_family == AF_INET6 &&
3315 	    data_dest.su_family == AF_INET6) {
3316 			/* XXX: more sanity checks! */
3317 		data_dest.su_scope_id = his_addr.su_scope_id;
3318 	}
3319 #endif
3320 
3321 	if (tmp != NULL)
3322 		free(tmp);
3323 	if (res)
3324 		freeaddrinfo(res);
3325 	return 0;
3326 
3327  parsefail:
3328 	reply(500, "Invalid argument, rejected.");
3329 	usedefault = 1;
3330 	if (tmp != NULL)
3331 		free(tmp);
3332 	if (res)
3333 		freeaddrinfo(res);
3334 	return -1;
3335 
3336  protounsupp:
3337 	epsv_protounsupp("Protocol not supported");
3338 	usedefault = 1;
3339 	if (tmp != NULL)
3340 		free(tmp);
3341 	return -1;
3342 }
3343 
3344 /*
3345  * 522 Protocol not supported (proto,...)
3346  * as we assume address family for control and data connections are the same,
3347  * we do not return the list of address families we support - instead, we
3348  * return the address family of the control connection.
3349  */
3350 void
epsv_protounsupp(const char * message)3351 epsv_protounsupp(const char *message)
3352 {
3353 	int proto;
3354 
3355 	proto = af2epsvproto(ctrl_addr.su_family);
3356 	if (proto < 0)
3357 		reply(501, "%s", message);	/* XXX */
3358 	else
3359 		reply(522, "%s, use (%d)", message, proto);
3360 }
3361 
3362 /*
3363  * Generate unique name for file with basename "local".
3364  * The file named "local" is already known to exist.
3365  * Generates failure reply on error.
3366  *
3367  * XXX:	this function should under go changes similar to
3368  *	the mktemp(3)/mkstemp(3) changes.
3369  */
3370 static char *
gunique(const char * local)3371 gunique(const char *local)
3372 {
3373 	static char new[MAXPATHLEN];
3374 	struct stat st;
3375 	char *cp;
3376 	int count;
3377 
3378 	cp = strrchr(local, '/');
3379 	if (cp)
3380 		*cp = '\0';
3381 	if (stat(cp ? local : ".", &st) < 0) {
3382 		perror_reply(553, cp ? local : ".");
3383 		return (NULL);
3384 	}
3385 	if (cp)
3386 		*cp = '/';
3387 	for (count = 1; count < 100; count++) {
3388 		(void)snprintf(new, sizeof(new) - 1, "%s.%d", local, count);
3389 		if (stat(new, &st) < 0)
3390 			return (new);
3391 	}
3392 	reply(452, "Unique file name cannot be created.");
3393 	return (NULL);
3394 }
3395 
3396 /*
3397  * Format and send reply containing system error number.
3398  */
3399 void
perror_reply(int code,const char * string)3400 perror_reply(int code, const char *string)
3401 {
3402 	int save_errno;
3403 
3404 	save_errno = errno;
3405 	reply(code, "%s: %s.", string, strerror(errno));
3406 	errno = save_errno;
3407 }
3408 
3409 static char *onefile[] = {
3410 	NULL,
3411 	0
3412 };
3413 
3414 void
send_file_list(const char * whichf)3415 send_file_list(const char *whichf)
3416 {
3417 	struct stat st;
3418 	DIR *dirp;
3419 	struct dirent *dir;
3420 	FILE *volatile dout;
3421 	char **volatile dirlist;
3422 	char *dirname, *p;
3423 	char *notglob;
3424 	int volatile simple;
3425 	int volatile freeglob;
3426 	glob_t gl;
3427 
3428 	dirp = NULL;
3429 	dout = NULL;
3430 	notglob = NULL;
3431 	simple = 0;
3432 	freeglob = 0;
3433 	urgflag = 0;
3434 
3435 	p = NULL;
3436 	if (strpbrk(whichf, "~{[*?") != NULL) {
3437 		int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE|GLOB_LIMIT;
3438 
3439 		memset(&gl, 0, sizeof(gl));
3440 		freeglob = 1;
3441 		if (glob(whichf, flags, 0, &gl)) {
3442 			reply(450, "Not found");
3443 			goto cleanup_send_file_list;
3444 		} else if (gl.gl_pathc == 0) {
3445 			errno = ENOENT;
3446 			perror_reply(450, whichf);
3447 			goto cleanup_send_file_list;
3448 		}
3449 		dirlist = gl.gl_pathv;
3450 	} else {
3451 		notglob = ftpd_strdup(whichf);
3452 		onefile[0] = notglob;
3453 		dirlist = onefile;
3454 		simple = 1;
3455 	}
3456 					/* XXX: } for vi sm */
3457 
3458 	while ((dirname = *dirlist++) != NULL) {
3459 		int trailingslash = 0;
3460 
3461 		if (stat(dirname, &st) < 0) {
3462 			/*
3463 			 * If user typed "ls -l", etc, and the client
3464 			 * used NLST, do what the user meant.
3465 			 */
3466 			/* XXX: nuke this support? */
3467 			if (dirname[0] == '-' && *dirlist == NULL &&
3468 			    transflag == 0) {
3469 				const char *argv[] = { INTERNAL_LS, "", NULL };
3470 
3471 				argv[1] = dirname;
3472 				retrieve(argv, dirname);
3473 				goto cleanup_send_file_list;
3474 			}
3475 			perror_reply(450, whichf);
3476 			goto cleanup_send_file_list;
3477 		}
3478 
3479 		if (S_ISREG(st.st_mode)) {
3480 			/*
3481 			 * XXXRFC:
3482 			 *	should we follow RFC959 and not work
3483 			 *	for non directories?
3484 			 */
3485 			if (dout == NULL) {
3486 				dout = dataconn("file list", (off_t)-1, "w");
3487 				if (dout == NULL)
3488 					goto cleanup_send_file_list;
3489 				transflag = 1;
3490 			}
3491 			cprintf(dout, "%s%s\n", dirname,
3492 			    type == TYPE_A ? "\r" : "");
3493 			continue;
3494 		} else if (!S_ISDIR(st.st_mode))
3495 			continue;
3496 
3497 		if (dirname[strlen(dirname) - 1] == '/')
3498 			trailingslash++;
3499 
3500 		if ((dirp = opendir(dirname)) == NULL)
3501 			continue;
3502 
3503 		while ((dir = readdir(dirp)) != NULL) {
3504 			char nbuf[MAXPATHLEN];
3505 
3506 			if (urgflag && handleoobcmd()) {
3507 				(void) closedir(dirp);
3508 				goto cleanup_send_file_list;
3509 			}
3510 
3511 			if (ISDOTDIR(dir->d_name) || ISDOTDOTDIR(dir->d_name))
3512 				continue;
3513 
3514 			(void)snprintf(nbuf, sizeof(nbuf), "%s%s%s", dirname,
3515 			    trailingslash ? "" : "/", dir->d_name);
3516 
3517 			/*
3518 			 * We have to do a stat to ensure it's
3519 			 * not a directory or special file.
3520 			 */
3521 			/*
3522 			 * XXXRFC:
3523 			 *	should we follow RFC959 and filter out
3524 			 *	non files ?   lukem - NO!, or not until
3525 			 *	our ftp client uses MLS{T,D} for completion.
3526 			 */
3527 			if (simple || (stat(nbuf, &st) == 0 &&
3528 			    S_ISREG(st.st_mode))) {
3529 				if (dout == NULL) {
3530 					dout = dataconn("file list", (off_t)-1,
3531 						"w");
3532 					if (dout == NULL) {
3533 						(void) closedir(dirp);
3534 						goto cleanup_send_file_list;
3535 					}
3536 					transflag = 1;
3537 				}
3538 				p = nbuf;
3539 				if (nbuf[0] == '.' && nbuf[1] == '/')
3540 					p = &nbuf[2];
3541 				cprintf(dout, "%s%s\n", p,
3542 				    type == TYPE_A ? "\r" : "");
3543 			}
3544 		}
3545 		(void) closedir(dirp);
3546 	}
3547 
3548 	if (dout == NULL)
3549 		reply(450, "No files found.");
3550 	else if (ferror(dout) != 0)
3551 		perror_reply(451, "Data connection");
3552 	else
3553 		reply(226, "Transfer complete.");
3554 
3555  cleanup_send_file_list:
3556 	closedataconn(dout);
3557 	transflag = 0;
3558 	urgflag = 0;
3559 	total_xfers++;
3560 	total_xfers_out++;
3561 	if (notglob)
3562 		free(notglob);
3563 	if (freeglob)
3564 		globfree(&gl);
3565 }
3566 
3567 char *
conffilename(const char * s)3568 conffilename(const char *s)
3569 {
3570 	static char filename[MAXPATHLEN];
3571 
3572 	if (*s == '/')
3573 		strlcpy(filename, s, sizeof(filename));
3574 	else
3575 		(void)snprintf(filename, sizeof(filename), "%s/%s", confdir ,s);
3576 	return (filename);
3577 }
3578 
3579 /*
3580  * logxfer --
3581  *	if logging > 1, then based on the arguments, syslog a message:
3582  *	 if bytes != -1		"<command> <file1> = <bytes> bytes"
3583  *	 else if file2 != NULL	"<command> <file1> <file2>"
3584  *	 else			"<command> <file1>"
3585  *	if elapsed != NULL, append "in xxx.yyy seconds"
3586  *	if error != NULL, append ": " + error
3587  *
3588  *	if doxferlog != 0, bytes != -1, and command is "get", "put",
3589  *	or "append", syslog and/or write a wu-ftpd style xferlog entry
3590  */
3591 void
logxfer(const char * command,off_t bytes,const char * file1,const char * file2,const struct timeval * elapsed,const char * error)3592 logxfer(const char *command, off_t bytes, const char *file1, const char *file2,
3593     const struct timeval *elapsed, const char *error)
3594 {
3595 	char		 buf[MAXPATHLEN * 2 + 100];
3596 	char		 realfile1[MAXPATHLEN], realfile2[MAXPATHLEN];
3597 	const char	*r1, *r2;
3598 	char		 direction;
3599 	size_t		 len;
3600 	time_t		 now;
3601 
3602 	if (logging <=1 && !doxferlog)
3603 		return;
3604 
3605 	r1 = r2 = NULL;
3606 	if ((r1 = realpath(file1, realfile1)) == NULL)
3607 		r1 = file1;
3608 	if (file2 != NULL)
3609 		if ((r2 = realpath(file2, realfile2)) == NULL)
3610 			r2 = file2;
3611 
3612 		/*
3613 		 * syslog command
3614 		 */
3615 	if (logging > 1) {
3616 		len = snprintf(buf, sizeof(buf), "%s %s", command, r1);
3617 		if (bytes != (off_t)-1)
3618 			len += snprintf(buf + len, sizeof(buf) - len,
3619 			    " = " LLF " byte%s", (LLT) bytes, PLURAL(bytes));
3620 		else if (r2 != NULL)
3621 			len += snprintf(buf + len, sizeof(buf) - len,
3622 			    " %s", r2);
3623 		if (elapsed != NULL)
3624 			len += snprintf(buf + len, sizeof(buf) - len,
3625 			    " in " LLF ".%.03ld seconds",
3626 			    (LLT)elapsed->tv_sec,
3627 			    (long)(elapsed->tv_usec / 1000));
3628 		if (error != NULL)
3629 			len += snprintf(buf + len, sizeof(buf) - len,
3630 			    ": %s", error);
3631 		syslog(LOG_INFO, "%s", buf);
3632 	}
3633 
3634 		/*
3635 		 * syslog wu-ftpd style log entry, prefixed with "xferlog: "
3636 		 */
3637 	if (!doxferlog || bytes == -1)
3638 		return;
3639 
3640 	if (strcmp(command, "get") == 0)
3641 		direction = 'o';
3642 	else if (strcmp(command, "put") == 0 || strcmp(command, "append") == 0)
3643 		direction = 'i';
3644 	else
3645 		return;
3646 
3647 	time(&now);
3648 	len = snprintf(buf, sizeof(buf),
3649 	    "%.24s " LLF " %s " LLF " %s %c %s %c %c %s FTP 0 * %c\n",
3650 
3651 /*
3652  * XXX: wu-ftpd puts ' (send)' or ' (recv)' in the syslog message, and removes
3653  *	the full date.  This may be problematic for accurate log parsing,
3654  *	given that syslog messages don't contain the full date.
3655  */
3656 	    ctime(&now),
3657 	    (LLT)
3658 	    (elapsed == NULL ? 0 : elapsed->tv_sec + (elapsed->tv_usec > 0)),
3659 	    remotehost,
3660 	    (LLT) bytes,
3661 	    r1,
3662 	    type == TYPE_A ? 'a' : 'b',
3663 	    "_",		/* XXX: take conversions into account? */
3664 	    direction,
3665 
3666 	    curclass.type == CLASS_GUEST ?  'a' :
3667 	    curclass.type == CLASS_CHROOT ? 'g' :
3668 	    curclass.type == CLASS_REAL ?   'r' : '?',
3669 
3670 	    curclass.type == CLASS_GUEST ? pw->pw_passwd : pw->pw_name,
3671 	    error != NULL ? 'i' : 'c'
3672 	    );
3673 
3674 	if ((doxferlog & 2) && xferlogfd != -1)
3675 		write(xferlogfd, buf, len);
3676 	if ((doxferlog & 1)) {
3677 		buf[len-1] = '\n';	/* strip \n from syslog message */
3678 		syslog(LOG_INFO, "xferlog: %s", buf);
3679 	}
3680 }
3681 
3682 /*
3683  * Log the resource usage.
3684  *
3685  * XXX: more resource usage to logging?
3686  */
3687 void
logrusage(const struct rusage * rusage_before,const struct rusage * rusage_after)3688 logrusage(const struct rusage *rusage_before,
3689     const struct rusage *rusage_after)
3690 {
3691 	struct timeval usrtime, systime;
3692 
3693 	if (logging <= 1)
3694 		return;
3695 
3696 	timersub(&rusage_after->ru_utime, &rusage_before->ru_utime, &usrtime);
3697 	timersub(&rusage_after->ru_stime, &rusage_before->ru_stime, &systime);
3698 	syslog(LOG_INFO, LLF ".%.03ldu " LLF ".%.03lds %ld+%ldio %ldpf+%ldw",
3699 	    (LLT)usrtime.tv_sec, (long)(usrtime.tv_usec / 1000),
3700 	    (LLT)systime.tv_sec, (long)(systime.tv_usec / 1000),
3701 	    rusage_after->ru_inblock - rusage_before->ru_inblock,
3702 	    rusage_after->ru_oublock - rusage_before->ru_oublock,
3703 	    rusage_after->ru_majflt - rusage_before->ru_majflt,
3704 	    rusage_after->ru_nswap - rusage_before->ru_nswap);
3705 }
3706 
3707 /*
3708  * Determine if `password' is valid for user given in `pw'.
3709  * Returns 2 if password expired, 1 if otherwise failed, 0 if ok
3710  */
3711 int
checkpassword(const struct passwd * pwent,const char * password)3712 checkpassword(const struct passwd *pwent, const char *password)
3713 {
3714 	const char *orig;
3715 	char	*new;
3716 	time_t	 change, expire, now;
3717 
3718 	change = expire = 0;
3719 	if (pwent == NULL)
3720 		return 1;
3721 
3722 	time(&now);
3723 	orig = pwent->pw_passwd;	/* save existing password */
3724 	expire = pwent->pw_expire;
3725 	change = pwent->pw_change;
3726 	if (change == _PASSWORD_CHGNOW)
3727 		change = now;
3728 
3729 	if (orig[0] == '\0')		/* don't allow empty passwords */
3730 		return 1;
3731 
3732 	new = crypt(password, orig);	/* encrypt given password */
3733 	if (strcmp(new, orig) != 0)	/* compare */
3734 		return 1;
3735 
3736 	if ((expire && now >= expire) || (change && now >= change))
3737 		return 2;		/* check if expired */
3738 
3739 	return 0;			/* OK! */
3740 }
3741 
3742 char *
ftpd_strdup(const char * s)3743 ftpd_strdup(const char *s)
3744 {
3745 	char *new = strdup(s);
3746 
3747 	if (new == NULL)
3748 		fatal("Local resource failure: malloc");
3749 		/* NOTREACHED */
3750 	return (new);
3751 }
3752 
3753 /*
3754  * As per fprintf(), but increment total_bytes and total_bytes_out,
3755  * by the appropriate amount.
3756  */
3757 void
cprintf(FILE * fd,const char * fmt,...)3758 cprintf(FILE *fd, const char *fmt, ...)
3759 {
3760 	off_t b;
3761 	va_list ap;
3762 
3763 	va_start(ap, fmt);
3764 	b = vfprintf(fd, fmt, ap);
3765 	va_end(ap);
3766 	total_bytes += b;
3767 	total_bytes_out += b;
3768 }
3769 
3770 #ifdef USE_PAM
3771 /*
3772  * the following code is stolen from imap-uw PAM authentication module and
3773  * login.c
3774  */
3775 typedef struct {
3776 	const char *uname;	/* user name */
3777 	int	    triedonce;	/* if non-zero, tried before */
3778 } ftpd_cred_t;
3779 
3780 static int
auth_conv(int num_msg,const struct pam_message ** msg,struct pam_response ** resp,void * appdata)3781 auth_conv(int num_msg, const struct pam_message **msg,
3782     struct pam_response **resp, void *appdata)
3783 {
3784 	int i, ret;
3785 	size_t n;
3786 	ftpd_cred_t *cred = (ftpd_cred_t *) appdata;
3787 	struct pam_response *myreply;
3788 	char pbuf[FTP_BUFLEN];
3789 
3790 	if (num_msg <= 0 || num_msg > PAM_MAX_NUM_MSG)
3791 		return (PAM_CONV_ERR);
3792 	myreply = calloc(num_msg, sizeof *myreply);
3793 	if (myreply == NULL)
3794 		return PAM_BUF_ERR;
3795 
3796 	for (i = 0; i < num_msg; i++) {
3797 		myreply[i].resp_retcode = 0;
3798 		myreply[i].resp = NULL;
3799 		switch (msg[i]->msg_style) {
3800 		case PAM_PROMPT_ECHO_ON:	/* user */
3801 			myreply[i].resp = ftpd_strdup(cred->uname);
3802 			/* PAM frees resp. */
3803 			break;
3804 		case PAM_PROMPT_ECHO_OFF:	/* authtok (password) */
3805 				/*
3806 				 * Only send a single 331 reply and
3807 				 * then expect a PASS.
3808 				 */
3809 			if (cred->triedonce) {
3810 				syslog(LOG_ERR,
3811 			"auth_conv: already performed PAM_PROMPT_ECHO_OFF");
3812 				goto fail;
3813 			}
3814 			cred->triedonce++;
3815 			if (msg[i]->msg[0] == '\0') {
3816 				(void)strlcpy(pbuf, "password", sizeof(pbuf));
3817 			} else {
3818 					/* Uncapitalize msg */
3819 				(void)strlcpy(pbuf, msg[i]->msg, sizeof(pbuf));
3820 				if (isupper((unsigned char)pbuf[0]))
3821 					pbuf[0] = tolower(
3822 					    (unsigned char)pbuf[0]);
3823 					/* Remove trailing ':' and whitespace */
3824 				n = strlen(pbuf);
3825 				while (n-- > 0) {
3826 					if (isspace((unsigned char)pbuf[n]) ||
3827 					    pbuf[n] == ':')
3828 						pbuf[n] = '\0';
3829 					else
3830 						break;
3831 				}
3832 			}
3833 				/* Send reply, wait for a response. */
3834 			reply(331, "User %s accepted, provide %s.",
3835 			    cred->uname, pbuf);
3836 			(void) alarm(curclass.timeout);
3837 			ret = get_line(pbuf, sizeof(pbuf)-1, stdin);
3838 			(void) alarm(0);
3839 			if (ret == -1) {
3840 				reply(221, "You could at least say goodbye.");
3841 				dologout(0);
3842 			} else if (ret == -2) {
3843 			    /* XXX: should we do this reply(-530, ..) ? */
3844 				reply(-530, "Command too long.");
3845 				goto fail;
3846 			}
3847 				/* Ensure it is PASS */
3848 			if (strncasecmp(pbuf, "PASS ", 5) != 0) {
3849 				syslog(LOG_ERR,
3850 				    "auth_conv: unexpected reply '%.4s'", pbuf);
3851 				/* XXX: should we do this reply(-530, ..) ? */
3852 				reply(-530, "Unexpected reply '%.4s'.", pbuf);
3853 				goto fail;
3854 			}
3855 				/* Strip CRLF from "PASS" reply */
3856 			n = strlen(pbuf);
3857 			while (--n >= 5 &&
3858 			    (pbuf[n] == '\r' || pbuf[n] == '\n'))
3859 			    pbuf[n] = '\0';
3860 				/* Copy password into reply */
3861 			myreply[i].resp = ftpd_strdup(pbuf+5);
3862 				/* PAM frees resp. */
3863 			break;
3864 		case PAM_TEXT_INFO:
3865 		case PAM_ERROR_MSG:
3866 			break;
3867 		default:			/* unknown message style */
3868 			goto fail;
3869 		}
3870 	}
3871 
3872 	*resp = myreply;
3873 	return PAM_SUCCESS;
3874 
3875  fail:
3876 	free(myreply);
3877 	*resp = NULL;
3878 	return PAM_CONV_ERR;
3879 }
3880 
3881 /*
3882  * Attempt to authenticate the user using PAM.  Returns 0 if the user is
3883  * authenticated, or 1 if not authenticated.  If some sort of PAM system
3884  * error occurs (e.g., the "/etc/pam.conf" file is missing) then this
3885  * function returns -1.  This can be used as an indication that we should
3886  * fall back to a different authentication mechanism.
3887  * pw maybe be updated to a new user if PAM_USER changes from curname.
3888  */
3889 static int
auth_pam(void)3890 auth_pam(void)
3891 {
3892 	const char *tmpl_user;
3893 	const void *item;
3894 	int rval;
3895 	int e;
3896 	ftpd_cred_t auth_cred = { curname, 0 };
3897 	struct pam_conv conv = { &auth_conv, &auth_cred };
3898 
3899 	e = pam_start("ftpd", curname, &conv, &pamh);
3900 	if (e != PAM_SUCCESS) {
3901 		/*
3902 		 * In OpenPAM, it's OK to pass NULL to pam_strerror()
3903 		 * if context creation has failed in the first place.
3904 		 */
3905 		syslog(LOG_ERR, "pam_start: %s", pam_strerror(NULL, e));
3906 		return -1;
3907 	}
3908 
3909 	e = pam_set_item(pamh, PAM_RHOST, remotehost);
3910 	if (e != PAM_SUCCESS) {
3911 		syslog(LOG_ERR, "pam_set_item(PAM_RHOST): %s",
3912 			pam_strerror(pamh, e));
3913 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
3914 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
3915 		}
3916 		pamh = NULL;
3917 		return -1;
3918 	}
3919 
3920 	e = pam_set_item(pamh, PAM_SOCKADDR, &his_addr);
3921 	if (e != PAM_SUCCESS) {
3922 		syslog(LOG_ERR, "pam_set_item(PAM_SOCKADDR): %s",
3923 			pam_strerror(pamh, e));
3924 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
3925 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
3926 		}
3927 		pamh = NULL;
3928 		return -1;
3929 	}
3930 
3931 	e = pam_authenticate(pamh, 0);
3932 	if (ftpd_debug)
3933 		syslog(LOG_DEBUG, "pam_authenticate: user '%s' returned %d",
3934 		    curname, e);
3935 	switch (e) {
3936 	case PAM_SUCCESS:
3937 		/*
3938 		 * With PAM we support the concept of a "template"
3939 		 * user.  The user enters a login name which is
3940 		 * authenticated by PAM, usually via a remote service
3941 		 * such as RADIUS or TACACS+.  If authentication
3942 		 * succeeds, a different but related "template" name
3943 		 * is used for setting the credentials, shell, and
3944 		 * home directory.  The name the user enters need only
3945 		 * exist on the remote authentication server, but the
3946 		 * template name must be present in the local password
3947 		 * database.
3948 		 *
3949 		 * This is supported by two various mechanisms in the
3950 		 * individual modules.  However, from the application's
3951 		 * point of view, the template user is always passed
3952 		 * back as a changed value of the PAM_USER item.
3953 		 */
3954 		if ((e = pam_get_item(pamh, PAM_USER, &item)) ==
3955 		    PAM_SUCCESS) {
3956 			tmpl_user = (const char *) item;
3957 			if (pw == NULL
3958 			    || strcmp(pw->pw_name, tmpl_user) != 0) {
3959 				pw = sgetpwnam(tmpl_user);
3960 				if (ftpd_debug)
3961 					syslog(LOG_DEBUG,
3962 					    "auth_pam: PAM changed "
3963 					    "user from '%s' to '%s'",
3964 					    curname, pw->pw_name);
3965 				(void)strlcpy(curname, pw->pw_name,
3966 				    curname_len);
3967 			}
3968 		} else
3969 			syslog(LOG_ERR, "Couldn't get PAM_USER: %s",
3970 			    pam_strerror(pamh, e));
3971 		rval = 0;
3972 		break;
3973 
3974 	case PAM_AUTH_ERR:
3975 	case PAM_USER_UNKNOWN:
3976 	case PAM_MAXTRIES:
3977 		rval = 1;
3978 		break;
3979 
3980 	default:
3981 		syslog(LOG_ERR, "pam_authenticate: %s", pam_strerror(pamh, e));
3982 		rval = -1;
3983 		break;
3984 	}
3985 
3986 	if (rval == 0) {
3987 		e = pam_acct_mgmt(pamh, 0);
3988 		if (e != PAM_SUCCESS) {
3989 			syslog(LOG_ERR, "pam_acct_mgmt: %s",
3990 						pam_strerror(pamh, e));
3991 			rval = 1;
3992 		}
3993 	}
3994 
3995 	if (rval != 0) {
3996 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
3997 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
3998 		}
3999 		pamh = NULL;
4000 	}
4001 	return rval;
4002 }
4003 
4004 #endif /* USE_PAM */
4005