xref: /freebsd/libexec/ftpd/ftpd.c (revision f0adf7f5cdd241db2f2c817683191a6ef64a4e95)
1 /*
2  * Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #if 0
35 #ifndef lint
36 static char copyright[] =
37 "@(#) Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994\n\
38 	The Regents of the University of California.  All rights reserved.\n";
39 #endif /* not lint */
40 #endif
41 
42 #ifndef lint
43 #if 0
44 static char sccsid[] = "@(#)ftpd.c	8.4 (Berkeley) 4/16/94";
45 #endif
46 static const char rcsid[] =
47   "$FreeBSD$";
48 #endif /* not lint */
49 
50 /*
51  * FTP server.
52  */
53 #include <sys/param.h>
54 #include <sys/ioctl.h>
55 #include <sys/mman.h>
56 #include <sys/socket.h>
57 #include <sys/stat.h>
58 #include <sys/time.h>
59 #include <sys/wait.h>
60 
61 #include <netinet/in.h>
62 #include <netinet/in_systm.h>
63 #include <netinet/ip.h>
64 #include <netinet/tcp.h>
65 
66 #define	FTP_NAMES
67 #include <arpa/ftp.h>
68 #include <arpa/inet.h>
69 #include <arpa/telnet.h>
70 
71 #include <ctype.h>
72 #include <dirent.h>
73 #include <err.h>
74 #include <errno.h>
75 #include <fcntl.h>
76 #include <glob.h>
77 #include <limits.h>
78 #include <netdb.h>
79 #include <pwd.h>
80 #include <grp.h>
81 #include <opie.h>
82 #include <signal.h>
83 #include <stdio.h>
84 #include <stdlib.h>
85 #include <string.h>
86 #include <syslog.h>
87 #include <time.h>
88 #include <unistd.h>
89 #include <libutil.h>
90 #ifdef	LOGIN_CAP
91 #include <login_cap.h>
92 #endif
93 
94 #ifdef USE_PAM
95 #include <security/pam_appl.h>
96 #endif
97 
98 #include "pathnames.h"
99 #include "extern.h"
100 
101 #include <stdarg.h>
102 
103 static char version[] = "Version 6.00LS";
104 #undef main
105 
106 extern	off_t restart_point;
107 extern	char cbuf[];
108 
109 union sockunion ctrl_addr;
110 union sockunion data_source;
111 union sockunion data_dest;
112 union sockunion his_addr;
113 union sockunion pasv_addr;
114 
115 int	daemon_mode;
116 int	data;
117 int	dataport;
118 int	hostinfo = 1;	/* print host-specific info in messages */
119 int	logged_in;
120 struct	passwd *pw;
121 char	*homedir;
122 int	ftpdebug;
123 int	timeout = 900;    /* timeout after 15 minutes of inactivity */
124 int	maxtimeout = 7200;/* don't allow idle time to be set beyond 2 hours */
125 int	logging;
126 int	restricted_data_ports = 1;
127 int	paranoid = 1;	  /* be extra careful about security */
128 int	anon_only = 0;    /* Only anonymous ftp allowed */
129 int	guest;
130 int	dochroot;
131 int	dowtmp = 1;
132 int	stats;
133 int	statfd = -1;
134 int	type;
135 int	form;
136 int	stru;			/* avoid C keyword */
137 int	mode;
138 int	usedefault = 1;		/* for data transfers */
139 int	pdata = -1;		/* for passive mode */
140 int	readonly=0;		/* Server is in readonly mode.	*/
141 int	noepsv=0;		/* EPSV command is disabled.	*/
142 int	noretr=0;		/* RETR command is disabled.	*/
143 int	noguestretr=0;		/* RETR command is disabled for anon users. */
144 int	noguestmkd=0;		/* MKD command is disabled for anon users. */
145 int	noguestmod=1;		/* anon users may not modify existing files. */
146 
147 static volatile sig_atomic_t recvurg;
148 sig_atomic_t transflag;
149 off_t	file_size;
150 off_t	byte_count;
151 #if !defined(CMASK) || CMASK == 0
152 #undef CMASK
153 #define CMASK 027
154 #endif
155 int	defumask = CMASK;		/* default umask value */
156 char	tmpline[7];
157 char	*hostname;
158 int	epsvall = 0;
159 
160 #ifdef VIRTUAL_HOSTING
161 char	*ftpuser;
162 
163 static struct ftphost {
164 	struct ftphost	*next;
165 	struct addrinfo *hostinfo;
166 	char		*hostname;
167 	char		*anonuser;
168 	char		*statfile;
169 	char		*welcome;
170 	char		*loginmsg;
171 } *thishost, *firsthost;
172 
173 #endif
174 char	remotehost[MAXHOSTNAMELEN];
175 char	*ident = NULL;
176 
177 static char ttyline[20];
178 char	*tty = ttyline;		/* for klogin */
179 
180 #ifdef USE_PAM
181 static int	auth_pam(struct passwd**, const char*);
182 pam_handle_t *pamh = NULL;
183 #endif
184 
185 static struct opie opiedata;
186 static char opieprompt[OPIE_CHALLENGE_MAX+1];
187 static int pwok;
188 
189 char	*pid_file = NULL;
190 
191 /*
192  * Limit number of pathnames that glob can return.
193  * A limit of 0 indicates the number of pathnames is unlimited.
194  */
195 #define MAXGLOBARGS	16384
196 #
197 
198 /*
199  * Timeout intervals for retrying connections
200  * to hosts that don't accept PORT cmds.  This
201  * is a kludge, but given the problems with TCP...
202  */
203 #define	SWAITMAX	90	/* wait at most 90 seconds */
204 #define	SWAITINT	5	/* interval between retries */
205 
206 int	swaitmax = SWAITMAX;
207 int	swaitint = SWAITINT;
208 
209 #ifdef SETPROCTITLE
210 #ifdef OLD_SETPROCTITLE
211 char	**Argv = NULL;		/* pointer to argument vector */
212 char	*LastArgv = NULL;	/* end of argv */
213 #endif /* OLD_SETPROCTITLE */
214 char	proctitle[LINE_MAX];	/* initial part of title */
215 #endif /* SETPROCTITLE */
216 
217 #define LOGCMD(cmd, file) \
218 	if (logging > 1) \
219 	    syslog(LOG_INFO,"%s %s%s", cmd, \
220 		*(file) == '/' ? "" : curdir(), file);
221 #define LOGCMD2(cmd, file1, file2) \
222 	 if (logging > 1) \
223 	    syslog(LOG_INFO,"%s %s%s %s%s", cmd, \
224 		*(file1) == '/' ? "" : curdir(), file1, \
225 		*(file2) == '/' ? "" : curdir(), file2);
226 #define LOGBYTES(cmd, file, cnt) \
227 	if (logging > 1) { \
228 		if (cnt == (off_t)-1) \
229 		    syslog(LOG_INFO,"%s %s%s", cmd, \
230 			*(file) == '/' ? "" : curdir(), file); \
231 		else \
232 		    syslog(LOG_INFO, "%s %s%s = %qd bytes", \
233 			cmd, (*(file) == '/') ? "" : curdir(), file, cnt); \
234 	}
235 
236 #ifdef VIRTUAL_HOSTING
237 static void	 inithosts(void);
238 static void	selecthost(union sockunion *);
239 #endif
240 static void	 ack(char *);
241 static void	 sigurg(int);
242 static void	 myoob(void);
243 static int	 checkuser(char *, char *, int, char **);
244 static FILE	*dataconn(char *, off_t, char *);
245 static void	 dolog(struct sockaddr *);
246 static char	*curdir(void);
247 static void	 end_login(void);
248 static FILE	*getdatasock(char *);
249 static int	 guniquefd(char *, char **);
250 static void	 lostconn(int);
251 static void	 sigquit(int);
252 static int	 receive_data(FILE *, FILE *);
253 static int	 send_data(FILE *, FILE *, off_t, off_t, int);
254 static struct passwd *
255 		 sgetpwnam(char *);
256 static char	*sgetsave(char *);
257 static void	 reapchild(int);
258 static void      logxfer(char *, off_t, time_t);
259 static char	*doublequote(char *);
260 static int	*socksetup(int, char *, const char *);
261 
262 static char *
263 curdir(void)
264 {
265 	static char path[MAXPATHLEN+1+1];	/* path + '/' + '\0' */
266 
267 	if (getcwd(path, sizeof(path)-2) == NULL)
268 		return ("");
269 	if (path[1] != '\0')		/* special case for root dir. */
270 		strcat(path, "/");
271 	/* For guest account, skip / since it's chrooted */
272 	return (guest ? path+1 : path);
273 }
274 
275 int
276 main(int argc, char *argv[], char **envp)
277 {
278 	int addrlen, ch, on = 1, tos;
279 	char *cp, line[LINE_MAX];
280 	FILE *fd;
281 	int error;
282 	char	*bindname = NULL;
283 	const char *bindport = "ftp";
284 	int	family = AF_UNSPEC;
285 	struct sigaction sa;
286 
287 	tzset();		/* in case no timezone database in ~ftp */
288 	sigemptyset(&sa.sa_mask);
289 	sa.sa_flags = SA_RESTART;
290 
291 #ifdef OLD_SETPROCTITLE
292 	/*
293 	 *  Save start and extent of argv for setproctitle.
294 	 */
295 	Argv = argv;
296 	while (*envp)
297 		envp++;
298 	LastArgv = envp[-1] + strlen(envp[-1]);
299 #endif /* OLD_SETPROCTITLE */
300 
301 
302 	while ((ch = getopt(argc, argv,
303 	                    "46a:AdDEhlmMoOp:P:rRSt:T:u:UvW")) != -1) {
304 		switch (ch) {
305 		case '4':
306 			family = (family == AF_INET6) ? AF_UNSPEC : AF_INET;
307 			break;
308 
309 		case '6':
310 			family = (family == AF_INET) ? AF_UNSPEC : AF_INET6;
311 			break;
312 
313 		case 'a':
314 			bindname = optarg;
315 			break;
316 
317 		case 'A':
318 			anon_only = 1;
319 			break;
320 
321 		case 'd':
322 			ftpdebug++;
323 			break;
324 
325 		case 'D':
326 			daemon_mode++;
327 			break;
328 
329 		case 'E':
330 			noepsv = 1;
331 			break;
332 
333 		case 'h':
334 			hostinfo = 0;
335 			break;
336 
337 		case 'l':
338 			logging++;	/* > 1 == extra logging */
339 			break;
340 
341 		case 'm':
342 			noguestmod = 0;
343 			break;
344 
345 		case 'M':
346 			noguestmkd = 1;
347 			break;
348 
349 		case 'o':
350 			noretr = 1;
351 			break;
352 
353 		case 'O':
354 			noguestretr = 1;
355 			break;
356 
357 		case 'p':
358 			pid_file = optarg;
359 			break;
360 
361 		case 'P':
362 			bindport = optarg;
363 			break;
364 
365 		case 'r':
366 			readonly = 1;
367 			break;
368 
369 		case 'R':
370 			paranoid = 0;
371 			break;
372 
373 		case 'S':
374 			stats++;
375 			break;
376 
377 		case 't':
378 			timeout = atoi(optarg);
379 			if (maxtimeout < timeout)
380 				maxtimeout = timeout;
381 			break;
382 
383 		case 'T':
384 			maxtimeout = atoi(optarg);
385 			if (timeout > maxtimeout)
386 				timeout = maxtimeout;
387 			break;
388 
389 		case 'u':
390 		    {
391 			long val = 0;
392 
393 			val = strtol(optarg, &optarg, 8);
394 			if (*optarg != '\0' || val < 0)
395 				warnx("bad value for -u");
396 			else
397 				defumask = val;
398 			break;
399 		    }
400 		case 'U':
401 			restricted_data_ports = 0;
402 			break;
403 
404 		case 'v':
405 			ftpdebug++;
406 			break;
407 
408 		case 'W':
409 			dowtmp = 0;
410 			break;
411 
412 		default:
413 			warnx("unknown flag -%c ignored", optopt);
414 			break;
415 		}
416 	}
417 
418 #ifdef VIRTUAL_HOSTING
419 	inithosts();
420 #endif
421 	(void) freopen(_PATH_DEVNULL, "w", stderr);
422 
423 	/*
424 	 * LOG_NDELAY sets up the logging connection immediately,
425 	 * necessary for anonymous ftp's that chroot and can't do it later.
426 	 */
427 	openlog("ftpd", LOG_PID | LOG_NDELAY, LOG_FTP);
428 
429 	if (daemon_mode) {
430 		int *ctl_sock, fd, maxfd = -1, nfds, i;
431 		fd_set defreadfds, readfds;
432 		pid_t pid;
433 
434 		/*
435 		 * Detach from parent.
436 		 */
437 		if (daemon(1, 1) < 0) {
438 			syslog(LOG_ERR, "failed to become a daemon");
439 			exit(1);
440 		}
441 		sa.sa_handler = reapchild;
442 		(void)sigaction(SIGCHLD, &sa, NULL);
443 
444 		/*
445 		 * Open a socket, bind it to the FTP port, and start
446 		 * listening.
447 		 */
448 		ctl_sock = socksetup(family, bindname, bindport);
449 		if (ctl_sock == NULL)
450 			exit(1);
451 
452 		FD_ZERO(&defreadfds);
453 		for (i = 1; i <= *ctl_sock; i++) {
454 			FD_SET(ctl_sock[i], &defreadfds);
455 			if (listen(ctl_sock[i], 32) < 0) {
456 				syslog(LOG_ERR, "control listen: %m");
457 				exit(1);
458 			}
459 			if (maxfd < ctl_sock[i])
460 				maxfd = ctl_sock[i];
461 		}
462 
463 		/*
464 		 * Atomically write process ID
465 		 */
466 		if (pid_file)
467 		{
468 			int fd;
469 			char buf[20];
470 
471 			fd = open(pid_file, O_CREAT | O_WRONLY | O_TRUNC
472 				| O_NONBLOCK | O_EXLOCK, 0644);
473 			if (fd < 0) {
474 				if (errno == EAGAIN)
475 					errx(1, "%s: file locked", pid_file);
476 				else
477 					err(1, "%s", pid_file);
478 			}
479 			snprintf(buf, sizeof(buf),
480 				"%lu\n", (unsigned long) getpid());
481 			if (write(fd, buf, strlen(buf)) < 0)
482 				err(1, "%s: write", pid_file);
483 			/* Leave the pid file open and locked */
484 		}
485 		/*
486 		 * Loop forever accepting connection requests and forking off
487 		 * children to handle them.
488 		 */
489 		while (1) {
490 			FD_COPY(&defreadfds, &readfds);
491 			nfds = select(maxfd + 1, &readfds, NULL, NULL, 0);
492 			if (nfds <= 0) {
493 				if (nfds < 0 && errno != EINTR)
494 					syslog(LOG_WARNING, "select: %m");
495 				continue;
496 			}
497 
498 			pid = -1;
499                         for (i = 1; i <= *ctl_sock; i++)
500 				if (FD_ISSET(ctl_sock[i], &readfds)) {
501 					addrlen = sizeof(his_addr);
502 					fd = accept(ctl_sock[i],
503 					    (struct sockaddr *)&his_addr,
504 					    &addrlen);
505 					if ((pid = fork()) == 0) {
506 						/* child */
507 						(void) dup2(fd, 0);
508 						(void) dup2(fd, 1);
509 						close(ctl_sock[i]);
510 					} else
511 						close(fd);
512 				}
513 			if (pid == 0)
514 				break;
515 		}
516 	} else {
517 		addrlen = sizeof(his_addr);
518 		if (getpeername(0, (struct sockaddr *)&his_addr, &addrlen) < 0) {
519 			syslog(LOG_ERR, "getpeername (%s): %m",argv[0]);
520 			exit(1);
521 		}
522 	}
523 
524 	sa.sa_handler = SIG_DFL;
525 	(void)sigaction(SIGCHLD, &sa, NULL);
526 
527 	sa.sa_handler = sigurg;
528 	sa.sa_flags = 0;		/* don't restart syscalls for SIGURG */
529 	(void)sigaction(SIGURG, &sa, NULL);
530 
531 	sigfillset(&sa.sa_mask);	/* block all signals in handler */
532 	sa.sa_flags = SA_RESTART;
533 	sa.sa_handler = sigquit;
534 	(void)sigaction(SIGHUP, &sa, NULL);
535 	(void)sigaction(SIGINT, &sa, NULL);
536 	(void)sigaction(SIGQUIT, &sa, NULL);
537 	(void)sigaction(SIGTERM, &sa, NULL);
538 
539 	sa.sa_handler = lostconn;
540 	(void)sigaction(SIGPIPE, &sa, NULL);
541 
542 	addrlen = sizeof(ctrl_addr);
543 	if (getsockname(0, (struct sockaddr *)&ctrl_addr, &addrlen) < 0) {
544 		syslog(LOG_ERR, "getsockname (%s): %m",argv[0]);
545 		exit(1);
546 	}
547 	dataport = ntohs(ctrl_addr.su_port) - 1; /* as per RFC 959 */
548 #ifdef VIRTUAL_HOSTING
549 	/* select our identity from virtual host table */
550 	selecthost(&ctrl_addr);
551 #endif
552 #ifdef IP_TOS
553 	if (ctrl_addr.su_family == AF_INET)
554       {
555 	tos = IPTOS_LOWDELAY;
556 	if (setsockopt(0, IPPROTO_IP, IP_TOS, &tos, sizeof(int)) < 0)
557 		syslog(LOG_WARNING, "control setsockopt (IP_TOS): %m");
558       }
559 #endif
560 	/*
561 	 * Disable Nagle on the control channel so that we don't have to wait
562 	 * for peer's ACK before issuing our next reply.
563 	 */
564 	if (setsockopt(0, IPPROTO_TCP, TCP_NODELAY, &on, sizeof(on)) < 0)
565 		syslog(LOG_WARNING, "control setsockopt (TCP_NODELAY): %m");
566 
567 	data_source.su_port = htons(ntohs(ctrl_addr.su_port) - 1);
568 
569 	/* set this here so klogin can use it... */
570 	(void)snprintf(ttyline, sizeof(ttyline), "ftp%d", getpid());
571 
572 	/* Try to handle urgent data inline */
573 #ifdef SO_OOBINLINE
574 	if (setsockopt(0, SOL_SOCKET, SO_OOBINLINE, &on, sizeof(on)) < 0)
575 		syslog(LOG_WARNING, "control setsockopt (SO_OOBINLINE): %m");
576 #endif
577 
578 #ifdef	F_SETOWN
579 	if (fcntl(fileno(stdin), F_SETOWN, getpid()) == -1)
580 		syslog(LOG_ERR, "fcntl F_SETOWN: %m");
581 #endif
582 	dolog((struct sockaddr *)&his_addr);
583 	/*
584 	 * Set up default state
585 	 */
586 	data = -1;
587 	type = TYPE_A;
588 	form = FORM_N;
589 	stru = STRU_F;
590 	mode = MODE_S;
591 	tmpline[0] = '\0';
592 
593 	/* If logins are disabled, print out the message. */
594 	if ((fd = fopen(_PATH_NOLOGIN,"r")) != NULL) {
595 		while (fgets(line, sizeof(line), fd) != NULL) {
596 			if ((cp = strchr(line, '\n')) != NULL)
597 				*cp = '\0';
598 			lreply(530, "%s", line);
599 		}
600 		(void) fflush(stdout);
601 		(void) fclose(fd);
602 		reply(530, "System not available.");
603 		exit(0);
604 	}
605 #ifdef VIRTUAL_HOSTING
606 	fd = fopen(thishost->welcome, "r");
607 #else
608 	fd = fopen(_PATH_FTPWELCOME, "r");
609 #endif
610 	if (fd != NULL) {
611 		while (fgets(line, sizeof(line), fd) != NULL) {
612 			if ((cp = strchr(line, '\n')) != NULL)
613 				*cp = '\0';
614 			lreply(220, "%s", line);
615 		}
616 		(void) fflush(stdout);
617 		(void) fclose(fd);
618 		/* reply(220,) must follow */
619 	}
620 #ifndef VIRTUAL_HOSTING
621 	if ((hostname = malloc(MAXHOSTNAMELEN)) == NULL)
622 		fatalerror("Ran out of memory.");
623 	(void) gethostname(hostname, MAXHOSTNAMELEN - 1);
624 	hostname[MAXHOSTNAMELEN - 1] = '\0';
625 #endif
626 	if (hostinfo)
627 		reply(220, "%s FTP server (%s) ready.", hostname, version);
628 	else
629 		reply(220, "FTP server ready.");
630 	for (;;)
631 		(void) yyparse();
632 	/* NOTREACHED */
633 }
634 
635 static void
636 lostconn(int signo)
637 {
638 
639 	if (ftpdebug)
640 		syslog(LOG_DEBUG, "lost connection");
641 	dologout(1);
642 }
643 
644 static void
645 sigquit(int signo)
646 {
647 
648 	syslog(LOG_ERR, "got signal %d", signo);
649 	dologout(1);
650 }
651 
652 #ifdef VIRTUAL_HOSTING
653 /*
654  * read in virtual host tables (if they exist)
655  */
656 
657 static void
658 inithosts(void)
659 {
660 	int insert;
661 	size_t len;
662 	FILE *fp;
663 	char *cp, *mp, *line;
664 	char *hostname;
665 	char *vhost, *anonuser, *statfile, *welcome, *loginmsg;
666 	struct ftphost *hrp, *lhrp;
667 	struct addrinfo hints, *res, *ai;
668 
669 	/*
670 	 * Fill in the default host information
671 	 */
672 	if ((hostname = malloc(MAXHOSTNAMELEN)) == NULL)
673 		fatalerror("Ran out of memory.");
674 	if (gethostname(hostname, MAXHOSTNAMELEN) < 0)
675 		hostname[0] = '\0';
676 	hostname[MAXHOSTNAMELEN - 1] = '\0';
677 	if ((hrp = malloc(sizeof(struct ftphost))) == NULL)
678 		fatalerror("Ran out of memory.");
679 	hrp->hostname = hostname;
680 	hrp->hostinfo = NULL;
681 
682 	memset(&hints, 0, sizeof(hints));
683 	hints.ai_flags = AI_CANONNAME;
684 	hints.ai_family = AF_UNSPEC;
685 	if (getaddrinfo(hrp->hostname, NULL, &hints, &res) == 0)
686 		hrp->hostinfo = res;
687 	hrp->statfile = _PATH_FTPDSTATFILE;
688 	hrp->welcome  = _PATH_FTPWELCOME;
689 	hrp->loginmsg = _PATH_FTPLOGINMESG;
690 	hrp->anonuser = "ftp";
691 	hrp->next = NULL;
692 	thishost = firsthost = lhrp = hrp;
693 	if ((fp = fopen(_PATH_FTPHOSTS, "r")) != NULL) {
694 		int addrsize, gothost;
695 		void *addr;
696 		struct hostent *hp;
697 
698 		while ((line = fgetln(fp, &len)) != NULL) {
699 			int	i, hp_error;
700 
701 			/* skip comments */
702 			if (line[0] == '#')
703 				continue;
704 			if (line[len - 1] == '\n') {
705 				line[len - 1] = '\0';
706 				mp = NULL;
707 			} else {
708 				if ((mp = malloc(len + 1)) == NULL)
709 					fatalerror("Ran out of memory.");
710 				memcpy(mp, line, len);
711 				mp[len] = '\0';
712 				line = mp;
713 			}
714 			cp = strtok(line, " \t");
715 			/* skip empty lines */
716 			if (cp == NULL)
717 				goto nextline;
718 			vhost = cp;
719 
720 			/* set defaults */
721 			anonuser = "ftp";
722 			statfile = _PATH_FTPDSTATFILE;
723 			welcome  = _PATH_FTPWELCOME;
724 			loginmsg = _PATH_FTPLOGINMESG;
725 
726 			/*
727 			 * Preparse the line so we can use its info
728 			 * for all the addresses associated with
729 			 * the virtual host name.
730 			 * Field 0, the virtual host name, is special:
731 			 * it's already parsed off and will be strdup'ed
732 			 * later, after we know its canonical form.
733 			 */
734 			for (i = 1; i < 5 && (cp = strtok(NULL, " \t")); i++)
735 				if (*cp != '-' && (cp = strdup(cp)))
736 					switch (i) {
737 					case 1:	/* anon user permissions */
738 						anonuser = cp;
739 						break;
740 					case 2: /* statistics file */
741 						statfile = cp;
742 						break;
743 					case 3: /* welcome message */
744 						welcome  = cp;
745 						break;
746 					case 4: /* login message */
747 						loginmsg = cp;
748 						break;
749 					default: /* programming error */
750 						abort();
751 						/* NOTREACHED */
752 					}
753 
754 			hints.ai_flags = 0;
755 			hints.ai_family = AF_UNSPEC;
756 			hints.ai_flags = AI_PASSIVE;
757 			if (getaddrinfo(vhost, NULL, &hints, &res) != 0)
758 				goto nextline;
759 			for (ai = res; ai != NULL && ai->ai_addr != NULL;
760 			     ai = ai->ai_next) {
761 
762 			gothost = 0;
763 			for (hrp = firsthost; hrp != NULL; hrp = hrp->next) {
764 				struct addrinfo *hi;
765 
766 				for (hi = hrp->hostinfo; hi != NULL;
767 				     hi = hi->ai_next)
768 					if (hi->ai_addrlen == ai->ai_addrlen &&
769 					    memcmp(hi->ai_addr,
770 						   ai->ai_addr,
771 						   ai->ai_addr->sa_len) == 0) {
772 						gothost++;
773 						break;
774 					}
775 				if (gothost)
776 					break;
777 			}
778 			if (hrp == NULL) {
779 				if ((hrp = malloc(sizeof(struct ftphost))) == NULL)
780 					goto nextline;
781 				hrp->hostname = NULL;
782 				insert = 1;
783 			} else {
784 				if (hrp->hostinfo && hrp->hostinfo != res)
785 					freeaddrinfo(hrp->hostinfo);
786 				insert = 0; /* host already in the chain */
787 			}
788 			hrp->hostinfo = res;
789 
790 			/*
791 			 * determine hostname to use.
792 			 * force defined name if there is a valid alias
793 			 * otherwise fallback to primary hostname
794 			 */
795 			/* XXX: getaddrinfo() can't do alias check */
796 			switch(hrp->hostinfo->ai_family) {
797 			case AF_INET:
798 				addr = &((struct sockaddr_in *)hrp->hostinfo->ai_addr)->sin_addr;
799 				addrsize = sizeof(struct in_addr);
800 				break;
801 			case AF_INET6:
802 				addr = &((struct sockaddr_in6 *)hrp->hostinfo->ai_addr)->sin6_addr;
803 				addrsize = sizeof(struct in6_addr);
804 				break;
805 			default:
806 				/* should not reach here */
807 				freeaddrinfo(hrp->hostinfo);
808 				if (insert)
809 					free(hrp); /*not in chain, can free*/
810 				else
811 					hrp->hostinfo = NULL; /*mark as blank*/
812 				goto nextline;
813 				/* NOTREACHED */
814 			}
815 			if ((hp = getipnodebyaddr(addr, addrsize,
816 						  hrp->hostinfo->ai_family,
817 						  &hp_error)) != NULL) {
818 				if (strcmp(vhost, hp->h_name) != 0) {
819 					if (hp->h_aliases == NULL)
820 						vhost = hp->h_name;
821 					else {
822 						i = 0;
823 						while (hp->h_aliases[i] &&
824 						       strcmp(vhost, hp->h_aliases[i]) != 0)
825 							++i;
826 						if (hp->h_aliases[i] == NULL)
827 							vhost = hp->h_name;
828 					}
829 				}
830 			}
831 			if (hrp->hostname &&
832 			    strcmp(hrp->hostname, vhost) != 0) {
833 				free(hrp->hostname);
834 				hrp->hostname = NULL;
835 			}
836 			if (hrp->hostname == NULL &&
837 			    (hrp->hostname = strdup(vhost)) == NULL) {
838 				freeaddrinfo(hrp->hostinfo);
839 				hrp->hostinfo = NULL; /* mark as blank */
840 				if (hp)
841 					freehostent(hp);
842 				goto nextline;
843 			}
844 			hrp->anonuser = anonuser;
845 			hrp->statfile = statfile;
846 			hrp->welcome  = welcome;
847 			hrp->loginmsg = loginmsg;
848 			if (insert) {
849 				hrp->next  = NULL;
850 				lhrp->next = hrp;
851 				lhrp = hrp;
852 			}
853 			if (hp)
854 				freehostent(hp);
855 		      }
856 nextline:
857 			if (mp)
858 				free(mp);
859 		}
860 		(void) fclose(fp);
861 	}
862 }
863 
864 static void
865 selecthost(union sockunion *su)
866 {
867 	struct ftphost	*hrp;
868 	u_int16_t port;
869 #ifdef INET6
870 	struct in6_addr *mapped_in6 = NULL;
871 #endif
872 	struct addrinfo *hi;
873 
874 #ifdef INET6
875 	/*
876 	 * XXX IPv4 mapped IPv6 addr consideraton,
877 	 * specified in rfc2373.
878 	 */
879 	if (su->su_family == AF_INET6 &&
880 	    IN6_IS_ADDR_V4MAPPED(&su->su_sin6.sin6_addr))
881 		mapped_in6 = &su->su_sin6.sin6_addr;
882 #endif
883 
884 	hrp = thishost = firsthost;	/* default */
885 	port = su->su_port;
886 	su->su_port = 0;
887 	while (hrp != NULL) {
888 	    for (hi = hrp->hostinfo; hi != NULL; hi = hi->ai_next) {
889 		if (memcmp(su, hi->ai_addr, hi->ai_addrlen) == 0) {
890 			thishost = hrp;
891 			break;
892 		}
893 #ifdef INET6
894 		/* XXX IPv4 mapped IPv6 addr consideraton */
895 		if (hi->ai_addr->sa_family == AF_INET && mapped_in6 != NULL &&
896 		    (memcmp(&mapped_in6->s6_addr[12],
897 			    &((struct sockaddr_in *)hi->ai_addr)->sin_addr,
898 			    sizeof(struct in_addr)) == 0)) {
899 			thishost = hrp;
900 			break;
901 		}
902 #endif
903 	    }
904 	    hrp = hrp->next;
905 	}
906 	su->su_port = port;
907 	/* setup static variables as appropriate */
908 	hostname = thishost->hostname;
909 	ftpuser = thishost->anonuser;
910 }
911 #endif
912 
913 /*
914  * Helper function for sgetpwnam().
915  */
916 static char *
917 sgetsave(char *s)
918 {
919 	char *new = malloc((unsigned) strlen(s) + 1);
920 
921 	if (new == NULL) {
922 		perror_reply(421, "Local resource failure: malloc");
923 		dologout(1);
924 		/* NOTREACHED */
925 	}
926 	(void) strcpy(new, s);
927 	return (new);
928 }
929 
930 /*
931  * Save the result of a getpwnam.  Used for USER command, since
932  * the data returned must not be clobbered by any other command
933  * (e.g., globbing).
934  */
935 static struct passwd *
936 sgetpwnam(char *name)
937 {
938 	static struct passwd save;
939 	struct passwd *p;
940 
941 	if ((p = getpwnam(name)) == NULL)
942 		return (p);
943 	if (save.pw_name) {
944 		free(save.pw_name);
945 		free(save.pw_passwd);
946 		free(save.pw_gecos);
947 		free(save.pw_dir);
948 		free(save.pw_shell);
949 	}
950 	save = *p;
951 	save.pw_name = sgetsave(p->pw_name);
952 	save.pw_passwd = sgetsave(p->pw_passwd);
953 	save.pw_gecos = sgetsave(p->pw_gecos);
954 	save.pw_dir = sgetsave(p->pw_dir);
955 	save.pw_shell = sgetsave(p->pw_shell);
956 	return (&save);
957 }
958 
959 static int login_attempts;	/* number of failed login attempts */
960 static int askpasswd;		/* had user command, ask for passwd */
961 static char curname[MAXLOGNAME];	/* current USER name */
962 
963 /*
964  * USER command.
965  * Sets global passwd pointer pw if named account exists and is acceptable;
966  * sets askpasswd if a PASS command is expected.  If logged in previously,
967  * need to reset state.  If name is "ftp" or "anonymous", the name is not in
968  * _PATH_FTPUSERS, and ftp account exists, set guest and pw, then just return.
969  * If account doesn't exist, ask for passwd anyway.  Otherwise, check user
970  * requesting login privileges.  Disallow anyone who does not have a standard
971  * shell as returned by getusershell().  Disallow anyone mentioned in the file
972  * _PATH_FTPUSERS to allow people such as root and uucp to be avoided.
973  */
974 void
975 user(char *name)
976 {
977 	char *cp, *shell;
978 
979 	if (logged_in) {
980 		if (guest) {
981 			reply(530, "Can't change user from guest login.");
982 			return;
983 		} else if (dochroot) {
984 			reply(530, "Can't change user from chroot user.");
985 			return;
986 		}
987 		end_login();
988 	}
989 
990 	guest = 0;
991 #ifdef VIRTUAL_HOSTING
992 	pw = sgetpwnam(thishost->anonuser);
993 #else
994 	pw = sgetpwnam("ftp");
995 #endif
996 	if (strcmp(name, "ftp") == 0 || strcmp(name, "anonymous") == 0) {
997 		if (checkuser(_PATH_FTPUSERS, "ftp", 0, NULL) ||
998 		    checkuser(_PATH_FTPUSERS, "anonymous", 0, NULL))
999 			reply(530, "User %s access denied.", name);
1000 		else if (pw != NULL) {
1001 			guest = 1;
1002 			askpasswd = 1;
1003 			reply(331,
1004 			"Guest login ok, send your email address as password.");
1005 		} else
1006 			reply(530, "User %s unknown.", name);
1007 		if (!askpasswd && logging)
1008 			syslog(LOG_NOTICE,
1009 			    "ANONYMOUS FTP LOGIN REFUSED FROM %s", remotehost);
1010 		return;
1011 	}
1012 	if (anon_only != 0) {
1013 		reply(530, "Sorry, only anonymous ftp allowed.");
1014 		return;
1015 	}
1016 
1017 	if ((pw = sgetpwnam(name))) {
1018 		if ((shell = pw->pw_shell) == NULL || *shell == 0)
1019 			shell = _PATH_BSHELL;
1020 		setusershell();
1021 		while ((cp = getusershell()) != NULL)
1022 			if (strcmp(cp, shell) == 0)
1023 				break;
1024 		endusershell();
1025 
1026 		if (cp == NULL || checkuser(_PATH_FTPUSERS, name, 1, NULL)) {
1027 			reply(530, "User %s access denied.", name);
1028 			if (logging)
1029 				syslog(LOG_NOTICE,
1030 				    "FTP LOGIN REFUSED FROM %s, %s",
1031 				    remotehost, name);
1032 			pw = (struct passwd *) NULL;
1033 			return;
1034 		}
1035 	}
1036 	if (logging)
1037 		strncpy(curname, name, sizeof(curname)-1);
1038 
1039 	pwok = 0;
1040 #ifdef USE_PAM
1041 	/* XXX Kluge! The conversation mechanism needs to be fixed. */
1042 #endif
1043 	if (opiechallenge(&opiedata, name, opieprompt) == 0) {
1044 		pwok = (pw != NULL) &&
1045 		       opieaccessfile(remotehost) &&
1046 		       opiealways(pw->pw_dir);
1047 		reply(331, "Response to %s %s for %s.",
1048 		      opieprompt, pwok ? "requested" : "required", name);
1049 	} else {
1050 		pwok = 1;
1051 		reply(331, "Password required for %s.", name);
1052 	}
1053 	askpasswd = 1;
1054 	/*
1055 	 * Delay before reading passwd after first failed
1056 	 * attempt to slow down passwd-guessing programs.
1057 	 */
1058 	if (login_attempts)
1059 		sleep((unsigned) login_attempts);
1060 }
1061 
1062 /*
1063  * Check if a user is in the file "fname",
1064  * return a pointer to a malloc'd string with the rest
1065  * of the matching line in "residue" if not NULL.
1066  */
1067 static int
1068 checkuser(char *fname, char *name, int pwset, char **residue)
1069 {
1070 	FILE *fd;
1071 	int found = 0;
1072 	size_t len;
1073 	char *line, *mp, *p;
1074 
1075 	if ((fd = fopen(fname, "r")) != NULL) {
1076 		while (!found && (line = fgetln(fd, &len)) != NULL) {
1077 			/* skip comments */
1078 			if (line[0] == '#')
1079 				continue;
1080 			if (line[len - 1] == '\n') {
1081 				line[len - 1] = '\0';
1082 				mp = NULL;
1083 			} else {
1084 				if ((mp = malloc(len + 1)) == NULL)
1085 					fatalerror("Ran out of memory.");
1086 				memcpy(mp, line, len);
1087 				mp[len] = '\0';
1088 				line = mp;
1089 			}
1090 			/* avoid possible leading and trailing whitespace */
1091 			p = strtok(line, " \t");
1092 			/* skip empty lines */
1093 			if (p == NULL)
1094 				goto nextline;
1095 			/*
1096 			 * if first chr is '@', check group membership
1097 			 */
1098 			if (p[0] == '@') {
1099 				int i = 0;
1100 				struct group *grp;
1101 
1102 				if (p[1] == '\0') /* single @ matches anyone */
1103 					found = 1;
1104 				else {
1105 					if ((grp = getgrnam(p+1)) == NULL)
1106 						goto nextline;
1107 					/*
1108 					 * Check user's default group
1109 					 */
1110 					if (pwset && grp->gr_gid == pw->pw_gid)
1111 						found = 1;
1112 					/*
1113 					 * Check supplementary groups
1114 					 */
1115 					while (!found && grp->gr_mem[i])
1116 						found = strcmp(name,
1117 							grp->gr_mem[i++])
1118 							== 0;
1119 				}
1120 			}
1121 			/*
1122 			 * Otherwise, just check for username match
1123 			 */
1124 			else
1125 				found = strcmp(p, name) == 0;
1126 			/*
1127 			 * Save the rest of line to "residue" if matched
1128 			 */
1129 			if (found && residue) {
1130 				if ((p = strtok(NULL, "")) != NULL)
1131 					p += strspn(p, " \t");
1132 				if (p && *p) {
1133 				 	if ((*residue = strdup(p)) == NULL)
1134 						fatalerror("Ran out of memory.");
1135 				} else
1136 					*residue = NULL;
1137 			}
1138 nextline:
1139 			if (mp)
1140 				free(mp);
1141 		}
1142 		(void) fclose(fd);
1143 	}
1144 	return (found);
1145 }
1146 
1147 /*
1148  * Terminate login as previous user, if any, resetting state;
1149  * used when USER command is given or login fails.
1150  */
1151 static void
1152 end_login(void)
1153 {
1154 #ifdef USE_PAM
1155 	int e;
1156 #endif
1157 
1158 	(void) seteuid((uid_t)0);
1159 	if (logged_in && dowtmp)
1160 		ftpd_logwtmp(ttyline, "", NULL);
1161 	pw = NULL;
1162 #ifdef	LOGIN_CAP
1163 	setusercontext(NULL, getpwuid(0), (uid_t)0,
1164 		       LOGIN_SETPRIORITY|LOGIN_SETRESOURCES|LOGIN_SETUMASK|
1165 		       LOGIN_SETMAC);
1166 #endif
1167 #ifdef USE_PAM
1168 	if ((e = pam_setcred(pamh, PAM_DELETE_CRED)) != PAM_SUCCESS)
1169 		syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, e));
1170 	if ((e = pam_close_session(pamh,0)) != PAM_SUCCESS)
1171 		syslog(LOG_ERR, "pam_close_session: %s", pam_strerror(pamh, e));
1172 	if ((e = pam_end(pamh, e)) != PAM_SUCCESS)
1173 		syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1174 	pamh = NULL;
1175 #endif
1176 	logged_in = 0;
1177 	guest = 0;
1178 	dochroot = 0;
1179 }
1180 
1181 #ifdef USE_PAM
1182 
1183 /*
1184  * the following code is stolen from imap-uw PAM authentication module and
1185  * login.c
1186  */
1187 #define COPY_STRING(s) (s ? strdup(s) : NULL)
1188 
1189 struct cred_t {
1190 	const char *uname;		/* user name */
1191 	const char *pass;		/* password */
1192 };
1193 typedef struct cred_t cred_t;
1194 
1195 static int
1196 auth_conv(int num_msg, const struct pam_message **msg,
1197 	  struct pam_response **resp, void *appdata)
1198 {
1199 	int i;
1200 	cred_t *cred = (cred_t *) appdata;
1201 	struct pam_response *reply;
1202 
1203 	reply = calloc(num_msg, sizeof *reply);
1204 	if (reply == NULL)
1205 		return PAM_BUF_ERR;
1206 
1207 	for (i = 0; i < num_msg; i++) {
1208 		switch (msg[i]->msg_style) {
1209 		case PAM_PROMPT_ECHO_ON:	/* assume want user name */
1210 			reply[i].resp_retcode = PAM_SUCCESS;
1211 			reply[i].resp = COPY_STRING(cred->uname);
1212 			/* PAM frees resp. */
1213 			break;
1214 		case PAM_PROMPT_ECHO_OFF:	/* assume want password */
1215 			reply[i].resp_retcode = PAM_SUCCESS;
1216 			reply[i].resp = COPY_STRING(cred->pass);
1217 			/* PAM frees resp. */
1218 			break;
1219 		case PAM_TEXT_INFO:
1220 		case PAM_ERROR_MSG:
1221 			reply[i].resp_retcode = PAM_SUCCESS;
1222 			reply[i].resp = NULL;
1223 			break;
1224 		default:			/* unknown message style */
1225 			free(reply);
1226 			return PAM_CONV_ERR;
1227 		}
1228 	}
1229 
1230 	*resp = reply;
1231 	return PAM_SUCCESS;
1232 }
1233 
1234 /*
1235  * Attempt to authenticate the user using PAM.  Returns 0 if the user is
1236  * authenticated, or 1 if not authenticated.  If some sort of PAM system
1237  * error occurs (e.g., the "/etc/pam.conf" file is missing) then this
1238  * function returns -1.  This can be used as an indication that we should
1239  * fall back to a different authentication mechanism.
1240  */
1241 static int
1242 auth_pam(struct passwd **ppw, const char *pass)
1243 {
1244 	pam_handle_t *pamh = NULL;
1245 	const char *tmpl_user;
1246 	const void *item;
1247 	int rval;
1248 	int e;
1249 	cred_t auth_cred = { (*ppw)->pw_name, pass };
1250 	struct pam_conv conv = { &auth_conv, &auth_cred };
1251 
1252 	e = pam_start("ftpd", (*ppw)->pw_name, &conv, &pamh);
1253 	if (e != PAM_SUCCESS) {
1254 		syslog(LOG_ERR, "pam_start: %s", pam_strerror(pamh, e));
1255 		return -1;
1256 	}
1257 
1258 	e = pam_set_item(pamh, PAM_RHOST, remotehost);
1259 	if (e != PAM_SUCCESS) {
1260 		syslog(LOG_ERR, "pam_set_item(PAM_RHOST): %s",
1261 			pam_strerror(pamh, e));
1262 		return -1;
1263 	}
1264 
1265 	e = pam_authenticate(pamh, 0);
1266 	switch (e) {
1267 	case PAM_SUCCESS:
1268 		/*
1269 		 * With PAM we support the concept of a "template"
1270 		 * user.  The user enters a login name which is
1271 		 * authenticated by PAM, usually via a remote service
1272 		 * such as RADIUS or TACACS+.  If authentication
1273 		 * succeeds, a different but related "template" name
1274 		 * is used for setting the credentials, shell, and
1275 		 * home directory.  The name the user enters need only
1276 		 * exist on the remote authentication server, but the
1277 		 * template name must be present in the local password
1278 		 * database.
1279 		 *
1280 		 * This is supported by two various mechanisms in the
1281 		 * individual modules.  However, from the application's
1282 		 * point of view, the template user is always passed
1283 		 * back as a changed value of the PAM_USER item.
1284 		 */
1285 		if ((e = pam_get_item(pamh, PAM_USER, &item)) ==
1286 		    PAM_SUCCESS) {
1287 			tmpl_user = (const char *) item;
1288 			if (strcmp((*ppw)->pw_name, tmpl_user) != 0)
1289 				*ppw = getpwnam(tmpl_user);
1290 		} else
1291 			syslog(LOG_ERR, "Couldn't get PAM_USER: %s",
1292 			    pam_strerror(pamh, e));
1293 		rval = 0;
1294 		break;
1295 
1296 	case PAM_AUTH_ERR:
1297 	case PAM_USER_UNKNOWN:
1298 	case PAM_MAXTRIES:
1299 		rval = 1;
1300 		break;
1301 
1302 	default:
1303 		syslog(LOG_ERR, "pam_authenticate: %s", pam_strerror(pamh, e));
1304 		rval = -1;
1305 		break;
1306 	}
1307 
1308 	if (rval == 0) {
1309 		e = pam_acct_mgmt(pamh, 0);
1310 		if (e == PAM_NEW_AUTHTOK_REQD) {
1311 			e = pam_chauthtok(pamh, PAM_CHANGE_EXPIRED_AUTHTOK);
1312 			if (e != PAM_SUCCESS) {
1313 				syslog(LOG_ERR, "pam_chauthtok: %s", pam_strerror(pamh, e));
1314 				rval = 1;
1315 			}
1316 		} else if (e != PAM_SUCCESS) {
1317 			rval = 1;
1318 		}
1319 	}
1320 
1321 	if (rval != 0) {
1322 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
1323 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1324 		}
1325 		pamh = NULL;
1326 	}
1327 	return rval;
1328 }
1329 
1330 #endif /* USE_PAM */
1331 
1332 void
1333 pass(char *passwd)
1334 {
1335 	int rval;
1336 	FILE *fd;
1337 #ifdef	LOGIN_CAP
1338 	login_cap_t *lc = NULL;
1339 #endif
1340 #ifdef USE_PAM
1341 	int e;
1342 #endif
1343 	char *chrootdir;
1344 	char *residue = NULL;
1345 	char *xpasswd;
1346 
1347 	if (logged_in || askpasswd == 0) {
1348 		reply(503, "Login with USER first.");
1349 		return;
1350 	}
1351 	askpasswd = 0;
1352 	if (!guest) {		/* "ftp" is only account allowed no password */
1353 		if (pw == NULL) {
1354 			rval = 1;	/* failure below */
1355 			goto skip;
1356 		}
1357 #ifdef USE_PAM
1358 		rval = auth_pam(&pw, passwd);
1359 		if (rval >= 0) {
1360 			opieunlock();
1361 			goto skip;
1362 		}
1363 #endif
1364 		if (opieverify(&opiedata, passwd) == 0)
1365 			xpasswd = pw->pw_passwd;
1366 		else if (pwok) {
1367 			xpasswd = crypt(passwd, pw->pw_passwd);
1368 			if (passwd[0] == '\0' && pw->pw_passwd[0] != '\0')
1369 				xpasswd = ":";
1370 		} else {
1371 			rval = 1;
1372 			goto skip;
1373 		}
1374 		rval = strcmp(pw->pw_passwd, xpasswd);
1375 		if (pw->pw_expire && time(NULL) >= pw->pw_expire)
1376 			rval = 1;	/* failure */
1377 skip:
1378 		/*
1379 		 * If rval == 1, the user failed the authentication check
1380 		 * above.  If rval == 0, either PAM or local authentication
1381 		 * succeeded.
1382 		 */
1383 		if (rval) {
1384 			reply(530, "Login incorrect.");
1385 			if (logging) {
1386 				syslog(LOG_NOTICE,
1387 				    "FTP LOGIN FAILED FROM %s",
1388 				    remotehost);
1389 				syslog(LOG_AUTHPRIV | LOG_NOTICE,
1390 				    "FTP LOGIN FAILED FROM %s, %s",
1391 				    remotehost, curname);
1392 			}
1393 			pw = NULL;
1394 			if (login_attempts++ >= 5) {
1395 				syslog(LOG_NOTICE,
1396 				    "repeated login failures from %s",
1397 				    remotehost);
1398 				exit(0);
1399 			}
1400 			return;
1401 		}
1402 	}
1403 	login_attempts = 0;		/* this time successful */
1404 	if (setegid((gid_t)pw->pw_gid) < 0) {
1405 		reply(550, "Can't set gid.");
1406 		return;
1407 	}
1408 	/* May be overridden by login.conf */
1409 	(void) umask(defumask);
1410 #ifdef	LOGIN_CAP
1411 	if ((lc = login_getpwclass(pw)) != NULL) {
1412 		char	remote_ip[MAXHOSTNAMELEN];
1413 
1414 		getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
1415 			remote_ip, sizeof(remote_ip) - 1, NULL, 0,
1416 			NI_NUMERICHOST);
1417 		remote_ip[sizeof(remote_ip) - 1] = 0;
1418 		if (!auth_hostok(lc, remotehost, remote_ip)) {
1419 			syslog(LOG_INFO|LOG_AUTH,
1420 			    "FTP LOGIN FAILED (HOST) as %s: permission denied.",
1421 			    pw->pw_name);
1422 			reply(530, "Permission denied.\n");
1423 			pw = NULL;
1424 			return;
1425 		}
1426 		if (!auth_timeok(lc, time(NULL))) {
1427 			reply(530, "Login not available right now.\n");
1428 			pw = NULL;
1429 			return;
1430 		}
1431 	}
1432 	setusercontext(lc, pw, (uid_t)0,
1433 		LOGIN_SETLOGIN|LOGIN_SETGROUP|LOGIN_SETPRIORITY|
1434 		LOGIN_SETRESOURCES|LOGIN_SETUMASK|LOGIN_SETMAC);
1435 #else
1436 	setlogin(pw->pw_name);
1437 	(void) initgroups(pw->pw_name, pw->pw_gid);
1438 #endif
1439 
1440 #ifdef USE_PAM
1441 	if (pamh) {
1442 		if ((e = pam_open_session(pamh, 0)) != PAM_SUCCESS) {
1443 			syslog(LOG_ERR, "pam_open_session: %s", pam_strerror(pamh, e));
1444 		} else if ((e = pam_setcred(pamh, PAM_ESTABLISH_CRED)) != PAM_SUCCESS) {
1445 			syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, e));
1446 		}
1447 	}
1448 #endif
1449 
1450 	/* open wtmp before chroot */
1451 	if (dowtmp)
1452 		ftpd_logwtmp(ttyline, pw->pw_name,
1453 		    (struct sockaddr *)&his_addr);
1454 	logged_in = 1;
1455 
1456 	if (guest && stats && statfd < 0)
1457 #ifdef VIRTUAL_HOSTING
1458 		statfd = open(thishost->statfile, O_WRONLY|O_APPEND);
1459 #else
1460 		statfd = open(_PATH_FTPDSTATFILE, O_WRONLY|O_APPEND);
1461 #endif
1462 		if (statfd < 0)
1463 			stats = 0;
1464 
1465 	dochroot =
1466 		checkuser(_PATH_FTPCHROOT, pw->pw_name, 1, &residue)
1467 #ifdef	LOGIN_CAP	/* Allow login.conf configuration as well */
1468 		|| login_getcapbool(lc, "ftp-chroot", 0)
1469 #endif
1470 	;
1471 	chrootdir = NULL;
1472 	/*
1473 	 * For a chrooted local user,
1474 	 * a) see whether ftpchroot(5) specifies a chroot directory,
1475 	 * b) extract the directory pathname from the line,
1476 	 * c) expand it to the absolute pathname if necessary.
1477 	 */
1478 	if (dochroot && residue &&
1479 	    (chrootdir = strtok(residue, " \t")) != NULL) {
1480 		if (chrootdir[0] != '/')
1481 			asprintf(&chrootdir, "%s/%s", pw->pw_dir, chrootdir);
1482 		else
1483 			chrootdir = strdup(chrootdir); /* so it can be freed */
1484 		if (chrootdir == NULL)
1485 			fatalerror("Ran out of memory.");
1486 	}
1487 	if (guest || dochroot) {
1488 		/*
1489 		 * If no chroot directory set yet, use the login directory.
1490 		 * Copy it so it can be modified while pw->pw_dir stays intact.
1491 		 */
1492 		if (chrootdir == NULL &&
1493 		    (chrootdir = strdup(pw->pw_dir)) == NULL)
1494 			fatalerror("Ran out of memory.");
1495 		/*
1496 		 * Check for the "/chroot/./home" syntax,
1497 		 * separate the chroot and home directory pathnames.
1498 		 */
1499 		if ((homedir = strstr(chrootdir, "/./")) != NULL) {
1500 			*(homedir++) = '\0';	/* wipe '/' */
1501 			homedir++;		/* skip '.' */
1502 			/* so chrootdir can be freed later */
1503 			if ((homedir = strdup(homedir)) == NULL)
1504 				fatalerror("Ran out of memory.");
1505 		} else {
1506 			/*
1507 			 * We MUST do a chdir() after the chroot. Otherwise
1508 			 * the old current directory will be accessible as "."
1509 			 * outside the new root!
1510 			 */
1511 			homedir = "/";
1512 		}
1513 		/*
1514 		 * Finally, do chroot()
1515 		 */
1516 		if (chroot(chrootdir) < 0) {
1517 			reply(550, "Can't change root.");
1518 			goto bad;
1519 		}
1520 	} else	/* real user w/o chroot */
1521 		homedir = pw->pw_dir;
1522 	/*
1523 	 * Set euid *before* doing chdir() so
1524 	 * a) the user won't be carried to a directory that he couldn't reach
1525 	 *    on his own due to no permission to upper path components,
1526 	 * b) NFS mounted homedirs w/restrictive permissions will be accessible
1527 	 *    (uid 0 has no root power over NFS if not mapped explicitly.)
1528 	 */
1529 	if (seteuid((uid_t)pw->pw_uid) < 0) {
1530 		reply(550, "Can't set uid.");
1531 		goto bad;
1532 	}
1533 	if (chdir(homedir) < 0) {
1534 		if (guest || dochroot) {
1535 			reply(550, "Can't change to base directory.");
1536 			goto bad;
1537 		} else {
1538 			if (chdir("/") < 0) {
1539 				reply(550, "Root is inaccessible.");
1540 				goto bad;
1541 			}
1542 			lreply(230, "No directory! Logging in with home=/");
1543 		}
1544 	}
1545 
1546 	/*
1547 	 * Display a login message, if it exists.
1548 	 * N.B. reply(230,) must follow the message.
1549 	 */
1550 #ifdef VIRTUAL_HOSTING
1551 	fd = fopen(thishost->loginmsg, "r");
1552 #else
1553 	fd = fopen(_PATH_FTPLOGINMESG, "r");
1554 #endif
1555 	if (fd != NULL) {
1556 		char *cp, line[LINE_MAX];
1557 
1558 		while (fgets(line, sizeof(line), fd) != NULL) {
1559 			if ((cp = strchr(line, '\n')) != NULL)
1560 				*cp = '\0';
1561 			lreply(230, "%s", line);
1562 		}
1563 		(void) fflush(stdout);
1564 		(void) fclose(fd);
1565 	}
1566 	if (guest) {
1567 		if (ident != NULL)
1568 			free(ident);
1569 		ident = strdup(passwd);
1570 		if (ident == NULL)
1571 			fatalerror("Ran out of memory.");
1572 
1573 		reply(230, "Guest login ok, access restrictions apply.");
1574 #ifdef SETPROCTITLE
1575 #ifdef VIRTUAL_HOSTING
1576 		if (thishost != firsthost)
1577 			snprintf(proctitle, sizeof(proctitle),
1578 				 "%s: anonymous(%s)/%s", remotehost, hostname,
1579 				 passwd);
1580 		else
1581 #endif
1582 			snprintf(proctitle, sizeof(proctitle),
1583 				 "%s: anonymous/%s", remotehost, passwd);
1584 		setproctitle("%s", proctitle);
1585 #endif /* SETPROCTITLE */
1586 		if (logging)
1587 			syslog(LOG_INFO, "ANONYMOUS FTP LOGIN FROM %s, %s",
1588 			    remotehost, passwd);
1589 	} else {
1590 		if (dochroot)
1591 			reply(230, "User %s logged in, "
1592 				   "access restrictions apply.", pw->pw_name);
1593 		else
1594 			reply(230, "User %s logged in.", pw->pw_name);
1595 
1596 #ifdef SETPROCTITLE
1597 		snprintf(proctitle, sizeof(proctitle),
1598 			 "%s: user/%s", remotehost, pw->pw_name);
1599 		setproctitle("%s", proctitle);
1600 #endif /* SETPROCTITLE */
1601 		if (logging)
1602 			syslog(LOG_INFO, "FTP LOGIN FROM %s as %s",
1603 			    remotehost, pw->pw_name);
1604 	}
1605 #ifdef	LOGIN_CAP
1606 	login_close(lc);
1607 #endif
1608 	if (chrootdir)
1609 		free(chrootdir);
1610 	if (residue)
1611 		free(residue);
1612 	return;
1613 bad:
1614 	/* Forget all about it... */
1615 #ifdef	LOGIN_CAP
1616 	login_close(lc);
1617 #endif
1618 	if (chrootdir)
1619 		free(chrootdir);
1620 	if (residue)
1621 		free(residue);
1622 	end_login();
1623 }
1624 
1625 void
1626 retrieve(char *cmd, char *name)
1627 {
1628 	FILE *fin, *dout;
1629 	struct stat st;
1630 	int (*closefunc)(FILE *);
1631 	time_t start;
1632 
1633 	if (cmd == 0) {
1634 		fin = fopen(name, "r"), closefunc = fclose;
1635 		st.st_size = 0;
1636 	} else {
1637 		char line[BUFSIZ];
1638 
1639 		(void) snprintf(line, sizeof(line), cmd, name), name = line;
1640 		fin = ftpd_popen(line, "r"), closefunc = ftpd_pclose;
1641 		st.st_size = -1;
1642 		st.st_blksize = BUFSIZ;
1643 	}
1644 	if (fin == NULL) {
1645 		if (errno != 0) {
1646 			perror_reply(550, name);
1647 			if (cmd == 0) {
1648 				LOGCMD("get", name);
1649 			}
1650 		}
1651 		return;
1652 	}
1653 	byte_count = -1;
1654 	if (cmd == 0) {
1655 		if (fstat(fileno(fin), &st) < 0) {
1656 			perror_reply(550, name);
1657 			goto done;
1658 		}
1659 		if (!S_ISREG(st.st_mode)) {
1660 			/*
1661 			 * Never sending a raw directory is a workaround
1662 			 * for buggy clients that will attempt to RETR
1663 			 * a directory before listing it, e.g., Mozilla.
1664 			 * Preventing a guest from getting irregular files
1665 			 * is a simple security measure.
1666 			 */
1667 			if (S_ISDIR(st.st_mode) || guest) {
1668 				reply(550, "%s: not a plain file.", name);
1669 				goto done;
1670 			}
1671 			st.st_size = -1;
1672 			/* st.st_blksize is set for all descriptor types */
1673 		}
1674 	}
1675 	if (restart_point) {
1676 		if (type == TYPE_A) {
1677 			off_t i, n;
1678 			int c;
1679 
1680 			n = restart_point;
1681 			i = 0;
1682 			while (i++ < n) {
1683 				if ((c=getc(fin)) == EOF) {
1684 					perror_reply(550, name);
1685 					goto done;
1686 				}
1687 				if (c == '\n')
1688 					i++;
1689 			}
1690 		} else if (lseek(fileno(fin), restart_point, L_SET) < 0) {
1691 			perror_reply(550, name);
1692 			goto done;
1693 		}
1694 	}
1695 	dout = dataconn(name, st.st_size, "w");
1696 	if (dout == NULL)
1697 		goto done;
1698 	time(&start);
1699 	send_data(fin, dout, st.st_blksize, st.st_size,
1700 		  restart_point == 0 && cmd == 0 && S_ISREG(st.st_mode));
1701 	if (cmd == 0 && guest && stats)
1702 		logxfer(name, st.st_size, start);
1703 	(void) fclose(dout);
1704 	data = -1;
1705 	pdata = -1;
1706 done:
1707 	if (cmd == 0)
1708 		LOGBYTES("get", name, byte_count);
1709 	(*closefunc)(fin);
1710 }
1711 
1712 void
1713 store(char *name, char *mode, int unique)
1714 {
1715 	int fd;
1716 	FILE *fout, *din;
1717 	int (*closefunc)(FILE *);
1718 
1719 	if (*mode == 'a') {		/* APPE */
1720 		if (unique) {
1721 			/* Programming error */
1722 			syslog(LOG_ERR, "Internal: unique flag to APPE");
1723 			unique = 0;
1724 		}
1725 		if (guest && noguestmod) {
1726 			reply(550, "Appending to existing file denied");
1727 			goto err;
1728 		}
1729 		restart_point = 0;	/* not affected by preceding REST */
1730 	}
1731 	if (unique)			/* STOU overrides REST */
1732 		restart_point = 0;
1733 	if (guest && noguestmod) {
1734 		if (restart_point) {	/* guest STOR w/REST */
1735 			reply(550, "Modifying existing file denied");
1736 			goto err;
1737 		} else			/* treat guest STOR as STOU */
1738 			unique = 1;
1739 	}
1740 
1741 	if (restart_point)
1742 		mode = "r+";	/* so ASCII manual seek can work */
1743 	if (unique) {
1744 		if ((fd = guniquefd(name, &name)) < 0)
1745 			goto err;
1746 		fout = fdopen(fd, mode);
1747 	} else
1748 		fout = fopen(name, mode);
1749 	closefunc = fclose;
1750 	if (fout == NULL) {
1751 		perror_reply(553, name);
1752 		goto err;
1753 	}
1754 	byte_count = -1;
1755 	if (restart_point) {
1756 		if (type == TYPE_A) {
1757 			off_t i, n;
1758 			int c;
1759 
1760 			n = restart_point;
1761 			i = 0;
1762 			while (i++ < n) {
1763 				if ((c=getc(fout)) == EOF) {
1764 					perror_reply(550, name);
1765 					goto done;
1766 				}
1767 				if (c == '\n')
1768 					i++;
1769 			}
1770 			/*
1771 			 * We must do this seek to "current" position
1772 			 * because we are changing from reading to
1773 			 * writing.
1774 			 */
1775 			if (fseeko(fout, (off_t)0, SEEK_CUR) < 0) {
1776 				perror_reply(550, name);
1777 				goto done;
1778 			}
1779 		} else if (lseek(fileno(fout), restart_point, L_SET) < 0) {
1780 			perror_reply(550, name);
1781 			goto done;
1782 		}
1783 	}
1784 	din = dataconn(name, (off_t)-1, "r");
1785 	if (din == NULL)
1786 		goto done;
1787 	if (receive_data(din, fout) == 0) {
1788 		if (unique)
1789 			reply(226, "Transfer complete (unique file name:%s).",
1790 			    name);
1791 		else
1792 			reply(226, "Transfer complete.");
1793 	}
1794 	(void) fclose(din);
1795 	data = -1;
1796 	pdata = -1;
1797 done:
1798 	LOGBYTES(*mode == 'a' ? "append" : "put", name, byte_count);
1799 	(*closefunc)(fout);
1800 	return;
1801 err:
1802 	LOGCMD(*mode == 'a' ? "append" : "put" , name);
1803 	return;
1804 }
1805 
1806 static FILE *
1807 getdatasock(char *mode)
1808 {
1809 	int on = 1, s, t, tries;
1810 
1811 	if (data >= 0)
1812 		return (fdopen(data, mode));
1813 	(void) seteuid((uid_t)0);
1814 
1815 	s = socket(data_dest.su_family, SOCK_STREAM, 0);
1816 	if (s < 0)
1817 		goto bad;
1818 	if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
1819 		syslog(LOG_WARNING, "data setsockopt (SO_REUSEADDR): %m");
1820 	/* anchor socket to avoid multi-homing problems */
1821 	data_source = ctrl_addr;
1822 	data_source.su_port = htons(dataport);
1823 	for (tries = 1; ; tries++) {
1824 		if (bind(s, (struct sockaddr *)&data_source,
1825 		    data_source.su_len) >= 0)
1826 			break;
1827 		if (errno != EADDRINUSE || tries > 10)
1828 			goto bad;
1829 		sleep(tries);
1830 	}
1831 	(void) seteuid((uid_t)pw->pw_uid);
1832 #ifdef IP_TOS
1833 	if (data_source.su_family == AF_INET)
1834       {
1835 	on = IPTOS_THROUGHPUT;
1836 	if (setsockopt(s, IPPROTO_IP, IP_TOS, &on, sizeof(int)) < 0)
1837 		syslog(LOG_WARNING, "data setsockopt (IP_TOS): %m");
1838       }
1839 #endif
1840 #ifdef TCP_NOPUSH
1841 	/*
1842 	 * Turn off push flag to keep sender TCP from sending short packets
1843 	 * at the boundaries of each write().  Should probably do a SO_SNDBUF
1844 	 * to set the send buffer size as well, but that may not be desirable
1845 	 * in heavy-load situations.
1846 	 */
1847 	on = 1;
1848 	if (setsockopt(s, IPPROTO_TCP, TCP_NOPUSH, &on, sizeof on) < 0)
1849 		syslog(LOG_WARNING, "data setsockopt (TCP_NOPUSH): %m");
1850 #endif
1851 #ifdef SO_SNDBUF
1852 	on = 65536;
1853 	if (setsockopt(s, SOL_SOCKET, SO_SNDBUF, &on, sizeof on) < 0)
1854 		syslog(LOG_WARNING, "data setsockopt (SO_SNDBUF): %m");
1855 #endif
1856 
1857 	return (fdopen(s, mode));
1858 bad:
1859 	/* Return the real value of errno (close may change it) */
1860 	t = errno;
1861 	(void) seteuid((uid_t)pw->pw_uid);
1862 	(void) close(s);
1863 	errno = t;
1864 	return (NULL);
1865 }
1866 
1867 static FILE *
1868 dataconn(char *name, off_t size, char *mode)
1869 {
1870 	char sizebuf[32];
1871 	FILE *file;
1872 	int retry = 0, tos, conerrno;
1873 
1874 	file_size = size;
1875 	byte_count = 0;
1876 	if (size != (off_t) -1)
1877 		(void) snprintf(sizebuf, sizeof(sizebuf), " (%qd bytes)", size);
1878 	else
1879 		*sizebuf = '\0';
1880 	if (pdata >= 0) {
1881 		union sockunion from;
1882 		int flags;
1883 		int s, fromlen = ctrl_addr.su_len;
1884 		struct timeval timeout;
1885 		fd_set set;
1886 
1887 		FD_ZERO(&set);
1888 		FD_SET(pdata, &set);
1889 
1890 		timeout.tv_usec = 0;
1891 		timeout.tv_sec = 120;
1892 
1893 		/*
1894 		 * Granted a socket is in the blocking I/O mode,
1895 		 * accept() will block after a successful select()
1896 		 * if the selected connection dies in between.
1897 		 * Therefore set the non-blocking I/O flag here.
1898 		 */
1899 		if ((flags = fcntl(pdata, F_GETFL, 0)) == -1 ||
1900 		    fcntl(pdata, F_SETFL, flags | O_NONBLOCK) == -1)
1901 			goto pdata_err;
1902 		if (select(pdata+1, &set, (fd_set *) 0, (fd_set *) 0, &timeout) <= 0 ||
1903 		    (s = accept(pdata, (struct sockaddr *) &from, &fromlen)) < 0)
1904 			goto pdata_err;
1905 		(void) close(pdata);
1906 		pdata = s;
1907 		/*
1908 		 * Unset the inherited non-blocking I/O flag
1909 		 * on the child socket so stdio can work on it.
1910 		 */
1911 		if ((flags = fcntl(pdata, F_GETFL, 0)) == -1 ||
1912 		    fcntl(pdata, F_SETFL, flags & ~O_NONBLOCK) == -1)
1913 			goto pdata_err;
1914 #ifdef IP_TOS
1915 		if (from.su_family == AF_INET)
1916 	      {
1917 		tos = IPTOS_THROUGHPUT;
1918 		if (setsockopt(s, IPPROTO_IP, IP_TOS, &tos, sizeof(int)) < 0)
1919 			syslog(LOG_WARNING, "pdata setsockopt (IP_TOS): %m");
1920 	      }
1921 #endif
1922 		reply(150, "Opening %s mode data connection for '%s'%s.",
1923 		     type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
1924 		return (fdopen(pdata, mode));
1925 pdata_err:
1926 		reply(425, "Can't open data connection.");
1927 		(void) close(pdata);
1928 		pdata = -1;
1929 		return (NULL);
1930 	}
1931 	if (data >= 0) {
1932 		reply(125, "Using existing data connection for '%s'%s.",
1933 		    name, sizebuf);
1934 		usedefault = 1;
1935 		return (fdopen(data, mode));
1936 	}
1937 	if (usedefault)
1938 		data_dest = his_addr;
1939 	usedefault = 1;
1940 	do {
1941 		file = getdatasock(mode);
1942 		if (file == NULL) {
1943 			char hostbuf[BUFSIZ], portbuf[BUFSIZ];
1944 			getnameinfo((struct sockaddr *)&data_source,
1945 				data_source.su_len, hostbuf, sizeof(hostbuf) - 1,
1946 				portbuf, sizeof(portbuf),
1947 				NI_NUMERICHOST|NI_NUMERICSERV);
1948 			reply(425, "Can't create data socket (%s,%s): %s.",
1949 				hostbuf, portbuf, strerror(errno));
1950 			return (NULL);
1951 		}
1952 		data = fileno(file);
1953 		conerrno = 0;
1954 		if (connect(data, (struct sockaddr *)&data_dest,
1955 		    data_dest.su_len) == 0)
1956 			break;
1957 		conerrno = errno;
1958 		(void) fclose(file);
1959 		data = -1;
1960 		if (conerrno == EADDRINUSE) {
1961 			sleep((unsigned) swaitint);
1962 			retry += swaitint;
1963 		} else {
1964 			break;
1965 		}
1966 	} while (retry <= swaitmax);
1967 	if (conerrno != 0) {
1968 		perror_reply(425, "Can't build data connection");
1969 		return (NULL);
1970 	}
1971 	reply(150, "Opening %s mode data connection for '%s'%s.",
1972 	     type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
1973 	return (file);
1974 }
1975 
1976 /*
1977  * Tranfer the contents of "instr" to "outstr" peer using the appropriate
1978  * encapsulation of the data subject to Mode, Structure, and Type.
1979  *
1980  * NB: Form isn't handled.
1981  */
1982 static int
1983 send_data(FILE *instr, FILE *outstr, off_t blksize, off_t filesize, int isreg)
1984 {
1985 	int c, cp, filefd, netfd;
1986 	char *buf;
1987 	off_t cnt;
1988 
1989 	transflag++;
1990 	switch (type) {
1991 
1992 	case TYPE_A:
1993 		cp = '\0';
1994 		while ((c = getc(instr)) != EOF) {
1995 			if (recvurg)
1996 				goto got_oob;
1997 			byte_count++;
1998 			if (c == '\n' && cp != '\r') {
1999 				if (ferror(outstr))
2000 					goto data_err;
2001 				(void) putc('\r', outstr);
2002 			}
2003 			(void) putc(c, outstr);
2004 			cp = c;
2005 		}
2006 		if (recvurg)
2007 			goto got_oob;
2008 		fflush(outstr);
2009 		transflag = 0;
2010 		if (ferror(instr))
2011 			goto file_err;
2012 		if (ferror(outstr))
2013 			goto data_err;
2014 		reply(226, "Transfer complete.");
2015 		return (0);
2016 
2017 	case TYPE_I:
2018 	case TYPE_L:
2019 		/*
2020 		 * isreg is only set if we are not doing restart and we
2021 		 * are sending a regular file
2022 		 */
2023 		netfd = fileno(outstr);
2024 		filefd = fileno(instr);
2025 
2026 		if (isreg) {
2027 
2028 			off_t offset;
2029 			int err;
2030 
2031 			err = cnt = offset = 0;
2032 
2033 			while (err != -1 && filesize > 0) {
2034 				err = sendfile(filefd, netfd, offset, 0,
2035 					(struct sf_hdtr *) NULL, &cnt, 0);
2036 				/*
2037 				 * Calculate byte_count before OOB processing.
2038 				 * It can be used in myoob() later.
2039 				 */
2040 				byte_count += cnt;
2041 				if (recvurg)
2042 					goto got_oob;
2043 				offset += cnt;
2044 				filesize -= cnt;
2045 
2046 				if (err == -1) {
2047 					if (!cnt)
2048 						goto oldway;
2049 
2050 					goto data_err;
2051 				}
2052 			}
2053 
2054 			transflag = 0;
2055 			reply(226, "Transfer complete.");
2056 			return (0);
2057 		}
2058 
2059 oldway:
2060 		if ((buf = malloc((u_int)blksize)) == NULL) {
2061 			transflag = 0;
2062 			perror_reply(451, "Local resource failure: malloc");
2063 			return (-1);
2064 		}
2065 
2066 		while ((cnt = read(filefd, buf, (u_int)blksize)) > 0 &&
2067 		    write(netfd, buf, cnt) == cnt)
2068 			byte_count += cnt;
2069 		transflag = 0;
2070 		(void)free(buf);
2071 		if (cnt != 0) {
2072 			if (cnt < 0)
2073 				goto file_err;
2074 			goto data_err;
2075 		}
2076 		reply(226, "Transfer complete.");
2077 		return (0);
2078 	default:
2079 		transflag = 0;
2080 		reply(550, "Unimplemented TYPE %d in send_data", type);
2081 		return (-1);
2082 	}
2083 
2084 data_err:
2085 	transflag = 0;
2086 	perror_reply(426, "Data connection");
2087 	return (-1);
2088 
2089 file_err:
2090 	transflag = 0;
2091 	perror_reply(551, "Error on input file");
2092 	return (-1);
2093 
2094 got_oob:
2095 	myoob();
2096 	recvurg = 0;
2097 	transflag = 0;
2098 	return (-1);
2099 }
2100 
2101 /*
2102  * Transfer data from peer to "outstr" using the appropriate encapulation of
2103  * the data subject to Mode, Structure, and Type.
2104  *
2105  * N.B.: Form isn't handled.
2106  */
2107 static int
2108 receive_data(FILE *instr, FILE *outstr)
2109 {
2110 	int c;
2111 	int cnt, bare_lfs;
2112 	char buf[BUFSIZ];
2113 
2114 	transflag++;
2115 	bare_lfs = 0;
2116 
2117 	switch (type) {
2118 
2119 	case TYPE_I:
2120 	case TYPE_L:
2121 		while ((cnt = read(fileno(instr), buf, sizeof(buf))) > 0) {
2122 			if (recvurg)
2123 				goto got_oob;
2124 			if (write(fileno(outstr), buf, cnt) != cnt)
2125 				goto file_err;
2126 			byte_count += cnt;
2127 		}
2128 		if (recvurg)
2129 			goto got_oob;
2130 		if (cnt < 0)
2131 			goto data_err;
2132 		transflag = 0;
2133 		return (0);
2134 
2135 	case TYPE_E:
2136 		reply(553, "TYPE E not implemented.");
2137 		transflag = 0;
2138 		return (-1);
2139 
2140 	case TYPE_A:
2141 		while ((c = getc(instr)) != EOF) {
2142 			if (recvurg)
2143 				goto got_oob;
2144 			byte_count++;
2145 			if (c == '\n')
2146 				bare_lfs++;
2147 			while (c == '\r') {
2148 				if (ferror(outstr))
2149 					goto data_err;
2150 				if ((c = getc(instr)) != '\n') {
2151 					(void) putc ('\r', outstr);
2152 					if (c == '\0' || c == EOF)
2153 						goto contin2;
2154 				}
2155 			}
2156 			(void) putc(c, outstr);
2157 	contin2:	;
2158 		}
2159 		if (recvurg)
2160 			goto got_oob;
2161 		fflush(outstr);
2162 		if (ferror(instr))
2163 			goto data_err;
2164 		if (ferror(outstr))
2165 			goto file_err;
2166 		transflag = 0;
2167 		if (bare_lfs) {
2168 			lreply(226,
2169 		"WARNING! %d bare linefeeds received in ASCII mode",
2170 			    bare_lfs);
2171 		(void)printf("   File may not have transferred correctly.\r\n");
2172 		}
2173 		return (0);
2174 	default:
2175 		reply(550, "Unimplemented TYPE %d in receive_data", type);
2176 		transflag = 0;
2177 		return (-1);
2178 	}
2179 
2180 data_err:
2181 	transflag = 0;
2182 	perror_reply(426, "Data Connection");
2183 	return (-1);
2184 
2185 file_err:
2186 	transflag = 0;
2187 	perror_reply(452, "Error writing file");
2188 	return (-1);
2189 
2190 got_oob:
2191 	myoob();
2192 	recvurg = 0;
2193 	transflag = 0;
2194 	return (-1);
2195 }
2196 
2197 void
2198 statfilecmd(char *filename)
2199 {
2200 	FILE *fin;
2201 	int atstart;
2202 	int c;
2203 	char line[LINE_MAX];
2204 
2205 	(void)snprintf(line, sizeof(line), _PATH_LS " -lgA %s", filename);
2206 	fin = ftpd_popen(line, "r");
2207 	lreply(211, "status of %s:", filename);
2208 	atstart = 1;
2209 	while ((c = getc(fin)) != EOF) {
2210 		if (c == '\n') {
2211 			if (ferror(stdout)){
2212 				perror_reply(421, "control connection");
2213 				(void) ftpd_pclose(fin);
2214 				dologout(1);
2215 				/* NOTREACHED */
2216 			}
2217 			if (ferror(fin)) {
2218 				perror_reply(551, filename);
2219 				(void) ftpd_pclose(fin);
2220 				return;
2221 			}
2222 			(void) putc('\r', stdout);
2223 		}
2224 		/*
2225 		 * RFC 959 says neutral text should be prepended before
2226 		 * a leading 3-digit number followed by whitespace, but
2227 		 * many ftp clients can be confused by any leading digits,
2228 		 * as a matter of fact.
2229 		 */
2230 		if (atstart && isdigit(c))
2231 			(void) putc(' ', stdout);
2232 		(void) putc(c, stdout);
2233 		atstart = (c == '\n');
2234 	}
2235 	(void) ftpd_pclose(fin);
2236 	reply(211, "End of Status");
2237 }
2238 
2239 void
2240 statcmd(void)
2241 {
2242 	union sockunion *su;
2243 	u_char *a, *p;
2244 	char hname[NI_MAXHOST];
2245 	int ispassive;
2246 
2247 	if (hostinfo) {
2248 		lreply(211, "%s FTP server status:", hostname);
2249 		printf("     %s\r\n", version);
2250 	} else
2251 		lreply(211, "FTP server status:");
2252 	printf("     Connected to %s", remotehost);
2253 	if (!getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
2254 			 hname, sizeof(hname) - 1, NULL, 0, NI_NUMERICHOST)) {
2255 		if (strcmp(hname, remotehost) != 0)
2256 			printf(" (%s)", hname);
2257 	}
2258 	printf("\r\n");
2259 	if (logged_in) {
2260 		if (guest)
2261 			printf("     Logged in anonymously\r\n");
2262 		else
2263 			printf("     Logged in as %s\r\n", pw->pw_name);
2264 	} else if (askpasswd)
2265 		printf("     Waiting for password\r\n");
2266 	else
2267 		printf("     Waiting for user name\r\n");
2268 	printf("     TYPE: %s", typenames[type]);
2269 	if (type == TYPE_A || type == TYPE_E)
2270 		printf(", FORM: %s", formnames[form]);
2271 	if (type == TYPE_L)
2272 #if CHAR_BIT == 8
2273 		printf(" %d", CHAR_BIT);
2274 #else
2275 		printf(" %d", bytesize);	/* need definition! */
2276 #endif
2277 	printf("; STRUcture: %s; transfer MODE: %s\r\n",
2278 	    strunames[stru], modenames[mode]);
2279 	if (data != -1)
2280 		printf("     Data connection open\r\n");
2281 	else if (pdata != -1) {
2282 		ispassive = 1;
2283 		su = &pasv_addr;
2284 		goto printaddr;
2285 	} else if (usedefault == 0) {
2286 		ispassive = 0;
2287 		su = &data_dest;
2288 printaddr:
2289 #define UC(b) (((int) b) & 0xff)
2290 		if (epsvall) {
2291 			printf("     EPSV only mode (EPSV ALL)\r\n");
2292 			goto epsvonly;
2293 		}
2294 
2295 		/* PORT/PASV */
2296 		if (su->su_family == AF_INET) {
2297 			a = (u_char *) &su->su_sin.sin_addr;
2298 			p = (u_char *) &su->su_sin.sin_port;
2299 			printf("     %s (%d,%d,%d,%d,%d,%d)\r\n",
2300 				ispassive ? "PASV" : "PORT",
2301 				UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
2302 				UC(p[0]), UC(p[1]));
2303 		}
2304 
2305 		/* LPRT/LPSV */
2306 	    {
2307 		int alen, af, i;
2308 
2309 		switch (su->su_family) {
2310 		case AF_INET:
2311 			a = (u_char *) &su->su_sin.sin_addr;
2312 			p = (u_char *) &su->su_sin.sin_port;
2313 			alen = sizeof(su->su_sin.sin_addr);
2314 			af = 4;
2315 			break;
2316 		case AF_INET6:
2317 			a = (u_char *) &su->su_sin6.sin6_addr;
2318 			p = (u_char *) &su->su_sin6.sin6_port;
2319 			alen = sizeof(su->su_sin6.sin6_addr);
2320 			af = 6;
2321 			break;
2322 		default:
2323 			af = 0;
2324 			break;
2325 		}
2326 		if (af) {
2327 			printf("     %s (%d,%d,", ispassive ? "LPSV" : "LPRT",
2328 				af, alen);
2329 			for (i = 0; i < alen; i++)
2330 				printf("%d,", UC(a[i]));
2331 			printf("%d,%d,%d)\r\n", 2, UC(p[0]), UC(p[1]));
2332 		}
2333 	    }
2334 
2335 epsvonly:;
2336 		/* EPRT/EPSV */
2337 	    {
2338 		int af;
2339 
2340 		switch (su->su_family) {
2341 		case AF_INET:
2342 			af = 1;
2343 			break;
2344 		case AF_INET6:
2345 			af = 2;
2346 			break;
2347 		default:
2348 			af = 0;
2349 			break;
2350 		}
2351 		if (af) {
2352 			union sockunion tmp;
2353 
2354 			tmp = *su;
2355 			if (tmp.su_family == AF_INET6)
2356 				tmp.su_sin6.sin6_scope_id = 0;
2357 			if (!getnameinfo((struct sockaddr *)&tmp, tmp.su_len,
2358 					hname, sizeof(hname) - 1, NULL, 0,
2359 					NI_NUMERICHOST)) {
2360 				printf("     %s |%d|%s|%d|\r\n",
2361 					ispassive ? "EPSV" : "EPRT",
2362 					af, hname, htons(tmp.su_port));
2363 			}
2364 		}
2365 	    }
2366 #undef UC
2367 	} else
2368 		printf("     No data connection\r\n");
2369 	reply(211, "End of status");
2370 }
2371 
2372 void
2373 fatalerror(char *s)
2374 {
2375 
2376 	reply(451, "Error in server: %s\n", s);
2377 	reply(221, "Closing connection due to server error.");
2378 	dologout(0);
2379 	/* NOTREACHED */
2380 }
2381 
2382 void
2383 reply(int n, const char *fmt, ...)
2384 {
2385 	va_list ap;
2386 
2387 	(void)printf("%d ", n);
2388 	va_start(ap, fmt);
2389 	(void)vprintf(fmt, ap);
2390 	va_end(ap);
2391 	(void)printf("\r\n");
2392 	(void)fflush(stdout);
2393 	if (ftpdebug) {
2394 		syslog(LOG_DEBUG, "<--- %d ", n);
2395 		va_start(ap, fmt);
2396 		vsyslog(LOG_DEBUG, fmt, ap);
2397 		va_end(ap);
2398 	}
2399 }
2400 
2401 void
2402 lreply(int n, const char *fmt, ...)
2403 {
2404 	va_list ap;
2405 
2406 	(void)printf("%d- ", n);
2407 	va_start(ap, fmt);
2408 	(void)vprintf(fmt, ap);
2409 	va_end(ap);
2410 	(void)printf("\r\n");
2411 	(void)fflush(stdout);
2412 	if (ftpdebug) {
2413 		syslog(LOG_DEBUG, "<--- %d- ", n);
2414 		va_start(ap, fmt);
2415 		vsyslog(LOG_DEBUG, fmt, ap);
2416 		va_end(ap);
2417 	}
2418 }
2419 
2420 static void
2421 ack(char *s)
2422 {
2423 
2424 	reply(250, "%s command successful.", s);
2425 }
2426 
2427 void
2428 nack(char *s)
2429 {
2430 
2431 	reply(502, "%s command not implemented.", s);
2432 }
2433 
2434 /* ARGSUSED */
2435 void
2436 yyerror(char *s)
2437 {
2438 	char *cp;
2439 
2440 	if ((cp = strchr(cbuf,'\n')))
2441 		*cp = '\0';
2442 	reply(500, "'%s': command not understood.", cbuf);
2443 }
2444 
2445 void
2446 delete(char *name)
2447 {
2448 	struct stat st;
2449 
2450 	LOGCMD("delete", name);
2451 	if (lstat(name, &st) < 0) {
2452 		perror_reply(550, name);
2453 		return;
2454 	}
2455 	if ((st.st_mode&S_IFMT) == S_IFDIR) {
2456 		if (rmdir(name) < 0) {
2457 			perror_reply(550, name);
2458 			return;
2459 		}
2460 		goto done;
2461 	}
2462 	if (guest && noguestmod) {
2463 		reply(550, "Operation not permitted");
2464 		return;
2465 	}
2466 	if (unlink(name) < 0) {
2467 		perror_reply(550, name);
2468 		return;
2469 	}
2470 done:
2471 	ack("DELE");
2472 }
2473 
2474 void
2475 cwd(char *path)
2476 {
2477 
2478 	if (chdir(path) < 0)
2479 		perror_reply(550, path);
2480 	else
2481 		ack("CWD");
2482 }
2483 
2484 void
2485 makedir(char *name)
2486 {
2487 	char *s;
2488 
2489 	LOGCMD("mkdir", name);
2490 	if (guest && noguestmkd)
2491 		reply(550, "%s: permission denied", name);
2492 	else if (mkdir(name, 0777) < 0)
2493 		perror_reply(550, name);
2494 	else {
2495 		if ((s = doublequote(name)) == NULL)
2496 			fatalerror("Ran out of memory.");
2497 		reply(257, "\"%s\" directory created.", s);
2498 		free(s);
2499 	}
2500 }
2501 
2502 void
2503 removedir(char *name)
2504 {
2505 
2506 	LOGCMD("rmdir", name);
2507 	if (rmdir(name) < 0)
2508 		perror_reply(550, name);
2509 	else
2510 		ack("RMD");
2511 }
2512 
2513 void
2514 pwd(void)
2515 {
2516 	char *s, path[MAXPATHLEN + 1];
2517 
2518 	if (getwd(path) == (char *)NULL)
2519 		reply(550, "%s.", path);
2520 	else {
2521 		if ((s = doublequote(path)) == NULL)
2522 			fatalerror("Ran out of memory.");
2523 		reply(257, "\"%s\" is current directory.", s);
2524 		free(s);
2525 	}
2526 }
2527 
2528 char *
2529 renamefrom(char *name)
2530 {
2531 	struct stat st;
2532 
2533 	if (guest && noguestmod) {
2534 		reply(550, "Operation not permitted");
2535 		return (NULL);
2536 	}
2537 	if (lstat(name, &st) < 0) {
2538 		perror_reply(550, name);
2539 		return (NULL);
2540 	}
2541 	reply(350, "File exists, ready for destination name");
2542 	return (name);
2543 }
2544 
2545 void
2546 renamecmd(char *from, char *to)
2547 {
2548 	struct stat st;
2549 
2550 	LOGCMD2("rename", from, to);
2551 
2552 	if (guest && (stat(to, &st) == 0)) {
2553 		reply(550, "%s: permission denied", to);
2554 		return;
2555 	}
2556 
2557 	if (rename(from, to) < 0)
2558 		perror_reply(550, "rename");
2559 	else
2560 		ack("RNTO");
2561 }
2562 
2563 static void
2564 dolog(struct sockaddr *who)
2565 {
2566 	int error;
2567 
2568 	realhostname_sa(remotehost, sizeof(remotehost) - 1, who, who->sa_len);
2569 
2570 #ifdef SETPROCTITLE
2571 #ifdef VIRTUAL_HOSTING
2572 	if (thishost != firsthost)
2573 		snprintf(proctitle, sizeof(proctitle), "%s: connected (to %s)",
2574 			 remotehost, hostname);
2575 	else
2576 #endif
2577 		snprintf(proctitle, sizeof(proctitle), "%s: connected",
2578 			 remotehost);
2579 	setproctitle("%s", proctitle);
2580 #endif /* SETPROCTITLE */
2581 
2582 	if (logging) {
2583 #ifdef VIRTUAL_HOSTING
2584 		if (thishost != firsthost)
2585 			syslog(LOG_INFO, "connection from %s (to %s)",
2586 			       remotehost, hostname);
2587 		else
2588 #endif
2589 		{
2590 			char	who_name[MAXHOSTNAMELEN];
2591 
2592 			error = getnameinfo(who, who->sa_len,
2593 					    who_name, sizeof(who_name) - 1,
2594 					    NULL, 0, NI_NUMERICHOST);
2595 			syslog(LOG_INFO, "connection from %s (%s)", remotehost,
2596 			       error == 0 ? who_name : "");
2597 		}
2598 	}
2599 }
2600 
2601 /*
2602  * Record logout in wtmp file
2603  * and exit with supplied status.
2604  */
2605 void
2606 dologout(int status)
2607 {
2608 	/*
2609 	 * Prevent reception of SIGURG from resulting in a resumption
2610 	 * back to the main program loop.
2611 	 */
2612 	transflag = 0;
2613 
2614 	if (logged_in && dowtmp) {
2615 		(void) seteuid((uid_t)0);
2616 		ftpd_logwtmp(ttyline, "", NULL);
2617 	}
2618 	/* beware of flushing buffers after a SIGPIPE */
2619 	_exit(status);
2620 }
2621 
2622 static void
2623 sigurg(int signo)
2624 {
2625 
2626 	recvurg = 1;
2627 }
2628 
2629 static void
2630 myoob(void)
2631 {
2632 	char *cp;
2633 
2634 	/* only process if transfer occurring */
2635 	if (!transflag)
2636 		return;
2637 	cp = tmpline;
2638 	if (getline(cp, 7, stdin) == NULL) {
2639 		reply(221, "You could at least say goodbye.");
2640 		dologout(0);
2641 	}
2642 	upper(cp);
2643 	if (strcmp(cp, "ABOR\r\n") == 0) {
2644 		tmpline[0] = '\0';
2645 		reply(426, "Transfer aborted. Data connection closed.");
2646 		reply(226, "Abort successful");
2647 	}
2648 	if (strcmp(cp, "STAT\r\n") == 0) {
2649 		tmpline[0] = '\0';
2650 		if (file_size != (off_t) -1)
2651 			reply(213, "Status: %qd of %qd bytes transferred",
2652 			    byte_count, file_size);
2653 		else
2654 			reply(213, "Status: %qd bytes transferred", byte_count);
2655 	}
2656 }
2657 
2658 /*
2659  * Note: a response of 425 is not mentioned as a possible response to
2660  *	the PASV command in RFC959. However, it has been blessed as
2661  *	a legitimate response by Jon Postel in a telephone conversation
2662  *	with Rick Adams on 25 Jan 89.
2663  */
2664 void
2665 passive(void)
2666 {
2667 	int len, on;
2668 	char *p, *a;
2669 
2670 	if (pdata >= 0)		/* close old port if one set */
2671 		close(pdata);
2672 
2673 	pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
2674 	if (pdata < 0) {
2675 		perror_reply(425, "Can't open passive connection");
2676 		return;
2677 	}
2678 	on = 1;
2679 	if (setsockopt(pdata, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
2680 		syslog(LOG_WARNING, "pdata setsockopt (SO_REUSEADDR): %m");
2681 
2682 	(void) seteuid((uid_t)0);
2683 
2684 #ifdef IP_PORTRANGE
2685 	if (ctrl_addr.su_family == AF_INET) {
2686 	    on = restricted_data_ports ? IP_PORTRANGE_HIGH
2687 				       : IP_PORTRANGE_DEFAULT;
2688 
2689 	    if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE,
2690 			    &on, sizeof(on)) < 0)
2691 		    goto pasv_error;
2692 	}
2693 #endif
2694 #ifdef IPV6_PORTRANGE
2695 	if (ctrl_addr.su_family == AF_INET6) {
2696 	    on = restricted_data_ports ? IPV6_PORTRANGE_HIGH
2697 				       : IPV6_PORTRANGE_DEFAULT;
2698 
2699 	    if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE,
2700 			    &on, sizeof(on)) < 0)
2701 		    goto pasv_error;
2702 	}
2703 #endif
2704 
2705 	pasv_addr = ctrl_addr;
2706 	pasv_addr.su_port = 0;
2707 	if (bind(pdata, (struct sockaddr *)&pasv_addr, pasv_addr.su_len) < 0)
2708 		goto pasv_error;
2709 
2710 	(void) seteuid((uid_t)pw->pw_uid);
2711 
2712 	len = sizeof(pasv_addr);
2713 	if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0)
2714 		goto pasv_error;
2715 	if (listen(pdata, 1) < 0)
2716 		goto pasv_error;
2717 	if (pasv_addr.su_family == AF_INET)
2718 		a = (char *) &pasv_addr.su_sin.sin_addr;
2719 	else if (pasv_addr.su_family == AF_INET6 &&
2720 		 IN6_IS_ADDR_V4MAPPED(&pasv_addr.su_sin6.sin6_addr))
2721 		a = (char *) &pasv_addr.su_sin6.sin6_addr.s6_addr[12];
2722 	else
2723 		goto pasv_error;
2724 
2725 	p = (char *) &pasv_addr.su_port;
2726 
2727 #define UC(b) (((int) b) & 0xff)
2728 
2729 	reply(227, "Entering Passive Mode (%d,%d,%d,%d,%d,%d)", UC(a[0]),
2730 		UC(a[1]), UC(a[2]), UC(a[3]), UC(p[0]), UC(p[1]));
2731 	return;
2732 
2733 pasv_error:
2734 	(void) seteuid((uid_t)pw->pw_uid);
2735 	(void) close(pdata);
2736 	pdata = -1;
2737 	perror_reply(425, "Can't open passive connection");
2738 	return;
2739 }
2740 
2741 /*
2742  * Long Passive defined in RFC 1639.
2743  *     228 Entering Long Passive Mode
2744  *         (af, hal, h1, h2, h3,..., pal, p1, p2...)
2745  */
2746 
2747 void
2748 long_passive(char *cmd, int pf)
2749 {
2750 	int len, on;
2751 	char *p, *a;
2752 
2753 	if (pdata >= 0)		/* close old port if one set */
2754 		close(pdata);
2755 
2756 	if (pf != PF_UNSPEC) {
2757 		if (ctrl_addr.su_family != pf) {
2758 			switch (ctrl_addr.su_family) {
2759 			case AF_INET:
2760 				pf = 1;
2761 				break;
2762 			case AF_INET6:
2763 				pf = 2;
2764 				break;
2765 			default:
2766 				pf = 0;
2767 				break;
2768 			}
2769 			/*
2770 			 * XXX
2771 			 * only EPRT/EPSV ready clients will understand this
2772 			 */
2773 			if (strcmp(cmd, "EPSV") == 0 && pf) {
2774 				reply(522, "Network protocol mismatch, "
2775 					"use (%d)", pf);
2776 			} else
2777 				reply(501, "Network protocol mismatch"); /*XXX*/
2778 
2779 			return;
2780 		}
2781 	}
2782 
2783 	pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
2784 	if (pdata < 0) {
2785 		perror_reply(425, "Can't open passive connection");
2786 		return;
2787 	}
2788 	on = 1;
2789 	if (setsockopt(pdata, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
2790 		syslog(LOG_WARNING, "pdata setsockopt (SO_REUSEADDR): %m");
2791 
2792 	(void) seteuid((uid_t)0);
2793 
2794 	pasv_addr = ctrl_addr;
2795 	pasv_addr.su_port = 0;
2796 	len = pasv_addr.su_len;
2797 
2798 #ifdef IP_PORTRANGE
2799 	if (ctrl_addr.su_family == AF_INET) {
2800 	    on = restricted_data_ports ? IP_PORTRANGE_HIGH
2801 				       : IP_PORTRANGE_DEFAULT;
2802 
2803 	    if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE,
2804 			    &on, sizeof(on)) < 0)
2805 		    goto pasv_error;
2806 	}
2807 #endif
2808 #ifdef IPV6_PORTRANGE
2809 	if (ctrl_addr.su_family == AF_INET6) {
2810 	    on = restricted_data_ports ? IPV6_PORTRANGE_HIGH
2811 				       : IPV6_PORTRANGE_DEFAULT;
2812 
2813 	    if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE,
2814 			    &on, sizeof(on)) < 0)
2815 		    goto pasv_error;
2816 	}
2817 #endif
2818 
2819 	if (bind(pdata, (struct sockaddr *)&pasv_addr, len) < 0)
2820 		goto pasv_error;
2821 
2822 	(void) seteuid((uid_t)pw->pw_uid);
2823 
2824 	if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0)
2825 		goto pasv_error;
2826 	if (listen(pdata, 1) < 0)
2827 		goto pasv_error;
2828 
2829 #define UC(b) (((int) b) & 0xff)
2830 
2831 	if (strcmp(cmd, "LPSV") == 0) {
2832 		p = (char *)&pasv_addr.su_port;
2833 		switch (pasv_addr.su_family) {
2834 		case AF_INET:
2835 			a = (char *) &pasv_addr.su_sin.sin_addr;
2836 		v4_reply:
2837 			reply(228,
2838 "Entering Long Passive Mode (%d,%d,%d,%d,%d,%d,%d,%d,%d)",
2839 			      4, 4, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
2840 			      2, UC(p[0]), UC(p[1]));
2841 			return;
2842 		case AF_INET6:
2843 			if (IN6_IS_ADDR_V4MAPPED(&pasv_addr.su_sin6.sin6_addr)) {
2844 				a = (char *) &pasv_addr.su_sin6.sin6_addr.s6_addr[12];
2845 				goto v4_reply;
2846 			}
2847 			a = (char *) &pasv_addr.su_sin6.sin6_addr;
2848 			reply(228,
2849 "Entering Long Passive Mode "
2850 "(%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d)",
2851 			      6, 16, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
2852 			      UC(a[4]), UC(a[5]), UC(a[6]), UC(a[7]),
2853 			      UC(a[8]), UC(a[9]), UC(a[10]), UC(a[11]),
2854 			      UC(a[12]), UC(a[13]), UC(a[14]), UC(a[15]),
2855 			      2, UC(p[0]), UC(p[1]));
2856 			return;
2857 		}
2858 	} else if (strcmp(cmd, "EPSV") == 0) {
2859 		switch (pasv_addr.su_family) {
2860 		case AF_INET:
2861 		case AF_INET6:
2862 			reply(229, "Entering Extended Passive Mode (|||%d|)",
2863 				ntohs(pasv_addr.su_port));
2864 			return;
2865 		}
2866 	} else {
2867 		/* more proper error code? */
2868 	}
2869 
2870 pasv_error:
2871 	(void) seteuid((uid_t)pw->pw_uid);
2872 	(void) close(pdata);
2873 	pdata = -1;
2874 	perror_reply(425, "Can't open passive connection");
2875 	return;
2876 }
2877 
2878 /*
2879  * Generate unique name for file with basename "local"
2880  * and open the file in order to avoid possible races.
2881  * Try "local" first, then "local.1", "local.2" etc, up to "local.99".
2882  * Return descriptor to the file, set "name" to its name.
2883  *
2884  * Generates failure reply on error.
2885  */
2886 static int
2887 guniquefd(char *local, char **name)
2888 {
2889 	static char new[MAXPATHLEN];
2890 	struct stat st;
2891 	char *cp;
2892 	int count;
2893 	int fd;
2894 
2895 	cp = strrchr(local, '/');
2896 	if (cp)
2897 		*cp = '\0';
2898 	if (stat(cp ? local : ".", &st) < 0) {
2899 		perror_reply(553, cp ? local : ".");
2900 		return (-1);
2901 	}
2902 	if (cp) {
2903 		/*
2904 		 * Let not overwrite dirname with counter suffix.
2905 		 * -4 is for /nn\0
2906 		 * In this extreme case dot won't be put in front of suffix.
2907 		 */
2908 		if (strlen(local) > sizeof(new) - 4) {
2909 			reply(553, "Pathname too long");
2910 			return (-1);
2911 		}
2912 		*cp = '/';
2913 	}
2914 	/* -4 is for the .nn<null> we put on the end below */
2915 	(void) snprintf(new, sizeof(new) - 4, "%s", local);
2916 	cp = new + strlen(new);
2917 	/*
2918 	 * Don't generate dotfile unless requested explicitly.
2919 	 * This covers the case when basename gets truncated off
2920 	 * by buffer size.
2921 	 */
2922 	if (cp > new && cp[-1] != '/')
2923 		*cp++ = '.';
2924 	for (count = 0; count < 100; count++) {
2925 		/* At count 0 try unmodified name */
2926 		if (count)
2927 			(void)sprintf(cp, "%d", count);
2928 		if ((fd = open(count ? new : local,
2929 		    O_RDWR | O_CREAT | O_EXCL, 0666)) >= 0) {
2930 			*name = count ? new : local;
2931 			return (fd);
2932 		}
2933 		if (errno != EEXIST) {
2934 			perror_reply(553, count ? new : local);
2935 			return (-1);
2936 		}
2937 	}
2938 	reply(452, "Unique file name cannot be created.");
2939 	return (-1);
2940 }
2941 
2942 /*
2943  * Format and send reply containing system error number.
2944  */
2945 void
2946 perror_reply(int code, char *string)
2947 {
2948 
2949 	reply(code, "%s: %s.", string, strerror(errno));
2950 }
2951 
2952 static char *onefile[] = {
2953 	"",
2954 	0
2955 };
2956 
2957 void
2958 send_file_list(char *whichf)
2959 {
2960 	struct stat st;
2961 	DIR *dirp = NULL;
2962 	struct dirent *dir;
2963 	FILE *dout = NULL;
2964 	char **dirlist, *dirname;
2965 	int simple = 0;
2966 	int freeglob = 0;
2967 	glob_t gl;
2968 
2969 	if (strpbrk(whichf, "~{[*?") != NULL) {
2970 		int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE;
2971 
2972 		memset(&gl, 0, sizeof(gl));
2973 		gl.gl_matchc = MAXGLOBARGS;
2974 		flags |= GLOB_LIMIT;
2975 		freeglob = 1;
2976 		if (glob(whichf, flags, 0, &gl)) {
2977 			reply(550, "not found");
2978 			goto out;
2979 		} else if (gl.gl_pathc == 0) {
2980 			errno = ENOENT;
2981 			perror_reply(550, whichf);
2982 			goto out;
2983 		}
2984 		dirlist = gl.gl_pathv;
2985 	} else {
2986 		onefile[0] = whichf;
2987 		dirlist = onefile;
2988 		simple = 1;
2989 	}
2990 
2991 	while ((dirname = *dirlist++)) {
2992 		if (stat(dirname, &st) < 0) {
2993 			/*
2994 			 * If user typed "ls -l", etc, and the client
2995 			 * used NLST, do what the user meant.
2996 			 */
2997 			if (dirname[0] == '-' && *dirlist == NULL &&
2998 			    transflag == 0) {
2999 				retrieve(_PATH_LS " %s", dirname);
3000 				goto out;
3001 			}
3002 			perror_reply(550, whichf);
3003 			if (dout != NULL) {
3004 				(void) fclose(dout);
3005 				transflag = 0;
3006 				data = -1;
3007 				pdata = -1;
3008 			}
3009 			goto out;
3010 		}
3011 
3012 		if (S_ISREG(st.st_mode)) {
3013 			if (dout == NULL) {
3014 				dout = dataconn("file list", (off_t)-1, "w");
3015 				if (dout == NULL)
3016 					goto out;
3017 				transflag++;
3018 			}
3019 			fprintf(dout, "%s%s\n", dirname,
3020 				type == TYPE_A ? "\r" : "");
3021 			byte_count += strlen(dirname) + 1;
3022 			continue;
3023 		} else if (!S_ISDIR(st.st_mode))
3024 			continue;
3025 
3026 		if ((dirp = opendir(dirname)) == NULL)
3027 			continue;
3028 
3029 		while ((dir = readdir(dirp)) != NULL) {
3030 			char nbuf[MAXPATHLEN];
3031 
3032 			if (recvurg) {
3033 				myoob();
3034 				recvurg = 0;
3035 				transflag = 0;
3036 				goto out;
3037 			}
3038 
3039 			if (dir->d_name[0] == '.' && dir->d_namlen == 1)
3040 				continue;
3041 			if (dir->d_name[0] == '.' && dir->d_name[1] == '.' &&
3042 			    dir->d_namlen == 2)
3043 				continue;
3044 
3045 			snprintf(nbuf, sizeof(nbuf),
3046 				"%s/%s", dirname, dir->d_name);
3047 
3048 			/*
3049 			 * We have to do a stat to insure it's
3050 			 * not a directory or special file.
3051 			 */
3052 			if (simple || (stat(nbuf, &st) == 0 &&
3053 			    S_ISREG(st.st_mode))) {
3054 				if (dout == NULL) {
3055 					dout = dataconn("file list", (off_t)-1,
3056 						"w");
3057 					if (dout == NULL)
3058 						goto out;
3059 					transflag++;
3060 				}
3061 				if (nbuf[0] == '.' && nbuf[1] == '/')
3062 					fprintf(dout, "%s%s\n", &nbuf[2],
3063 						type == TYPE_A ? "\r" : "");
3064 				else
3065 					fprintf(dout, "%s%s\n", nbuf,
3066 						type == TYPE_A ? "\r" : "");
3067 				byte_count += strlen(nbuf) + 1;
3068 			}
3069 		}
3070 		(void) closedir(dirp);
3071 	}
3072 
3073 	if (dout == NULL)
3074 		reply(550, "No files found.");
3075 	else if (ferror(dout) != 0)
3076 		perror_reply(550, "Data connection");
3077 	else
3078 		reply(226, "Transfer complete.");
3079 
3080 	transflag = 0;
3081 	if (dout != NULL)
3082 		(void) fclose(dout);
3083 	data = -1;
3084 	pdata = -1;
3085 out:
3086 	if (freeglob) {
3087 		freeglob = 0;
3088 		globfree(&gl);
3089 	}
3090 }
3091 
3092 void
3093 reapchild(int signo)
3094 {
3095 	while (wait3(NULL, WNOHANG, NULL) > 0);
3096 }
3097 
3098 #ifdef OLD_SETPROCTITLE
3099 /*
3100  * Clobber argv so ps will show what we're doing.  (Stolen from sendmail.)
3101  * Warning, since this is usually started from inetd.conf, it often doesn't
3102  * have much of an environment or arglist to overwrite.
3103  */
3104 void
3105 setproctitle(const char *fmt, ...)
3106 {
3107 	int i;
3108 	va_list ap;
3109 	char *p, *bp, ch;
3110 	char buf[LINE_MAX];
3111 
3112 	va_start(ap, fmt);
3113 	(void)vsnprintf(buf, sizeof(buf), fmt, ap);
3114 
3115 	/* make ps print our process name */
3116 	p = Argv[0];
3117 	*p++ = '-';
3118 
3119 	i = strlen(buf);
3120 	if (i > LastArgv - p - 2) {
3121 		i = LastArgv - p - 2;
3122 		buf[i] = '\0';
3123 	}
3124 	bp = buf;
3125 	while (ch = *bp++)
3126 		if (ch != '\n' && ch != '\r')
3127 			*p++ = ch;
3128 	while (p < LastArgv)
3129 		*p++ = ' ';
3130 }
3131 #endif /* OLD_SETPROCTITLE */
3132 
3133 static void
3134 logxfer(char *name, off_t size, time_t start)
3135 {
3136 	char buf[1024];
3137 	char path[MAXPATHLEN + 1];
3138 	time_t now;
3139 
3140 	if (statfd >= 0 && getwd(path) != NULL) {
3141 		time(&now);
3142 		snprintf(buf, sizeof(buf), "%.20s!%s!%s!%s/%s!%qd!%ld\n",
3143 			ctime(&now)+4, ident, remotehost,
3144 			path, name, (long long)size,
3145 			(long)(now - start + (now == start)));
3146 		write(statfd, buf, strlen(buf));
3147 	}
3148 }
3149 
3150 static char *
3151 doublequote(char *s)
3152 {
3153 	int n;
3154 	char *p, *s2;
3155 
3156 	for (p = s, n = 0; *p; p++)
3157 		if (*p == '"')
3158 			n++;
3159 
3160 	if ((s2 = malloc(p - s + n + 1)) == NULL)
3161 		return (NULL);
3162 
3163 	for (p = s2; *s; s++, p++) {
3164 		if ((*p = *s) == '"')
3165 			*(++p) = '"';
3166 	}
3167 	*p = '\0';
3168 
3169 	return (s2);
3170 }
3171 
3172 /* setup server socket for specified address family */
3173 /* if af is PF_UNSPEC more than one socket may be returned */
3174 /* the returned list is dynamically allocated, so caller needs to free it */
3175 static int *
3176 socksetup(int af, char *bindname, const char *bindport)
3177 {
3178 	struct addrinfo hints, *res, *r;
3179 	int error, maxs, *s, *socks;
3180 	const int on = 1;
3181 
3182 	memset(&hints, 0, sizeof(hints));
3183 	hints.ai_flags = AI_PASSIVE;
3184 	hints.ai_family = af;
3185 	hints.ai_socktype = SOCK_STREAM;
3186 	error = getaddrinfo(bindname, bindport, &hints, &res);
3187 	if (error) {
3188 		syslog(LOG_ERR, "%s", gai_strerror(error));
3189 		if (error == EAI_SYSTEM)
3190 			syslog(LOG_ERR, "%s", strerror(errno));
3191 		return NULL;
3192 	}
3193 
3194 	/* Count max number of sockets we may open */
3195 	for (maxs = 0, r = res; r; r = r->ai_next, maxs++)
3196 		;
3197 	socks = malloc((maxs + 1) * sizeof(int));
3198 	if (!socks) {
3199 		freeaddrinfo(res);
3200 		syslog(LOG_ERR, "couldn't allocate memory for sockets");
3201 		return NULL;
3202 	}
3203 
3204 	*socks = 0;   /* num of sockets counter at start of array */
3205 	s = socks + 1;
3206 	for (r = res; r; r = r->ai_next) {
3207 		*s = socket(r->ai_family, r->ai_socktype, r->ai_protocol);
3208 		if (*s < 0) {
3209 			syslog(LOG_DEBUG, "control socket: %m");
3210 			continue;
3211 		}
3212 		if (setsockopt(*s, SOL_SOCKET, SO_REUSEADDR,
3213 		    &on, sizeof(on)) < 0)
3214 			syslog(LOG_WARNING,
3215 			    "control setsockopt (SO_REUSEADDR): %m");
3216 		if (r->ai_family == AF_INET6) {
3217 			if (setsockopt(*s, IPPROTO_IPV6, IPV6_V6ONLY,
3218 			    &on, sizeof(on)) < 0)
3219 				syslog(LOG_WARNING,
3220 				    "control setsockopt (IPV6_V6ONLY): %m");
3221 		}
3222 		if (bind(*s, r->ai_addr, r->ai_addrlen) < 0) {
3223 			syslog(LOG_DEBUG, "control bind: %m");
3224 			close(*s);
3225 			continue;
3226 		}
3227 		(*socks)++;
3228 		s++;
3229 	}
3230 
3231 	if (res)
3232 		freeaddrinfo(res);
3233 
3234 	if (*socks == 0) {
3235 		syslog(LOG_ERR, "control socket: Couldn't bind to any socket");
3236 		free(socks);
3237 		return NULL;
3238 	}
3239 	return(socks);
3240 }
3241