xref: /freebsd/libexec/ftpd/ftpd.c (revision 52ec752989b2e6d4e9a59a8ff25d8ff596d85e62)
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 	if ((fd = fopen(thishost->welcome, "r")) != NULL) {
607 #else
608 	if ((fd = fopen(_PATH_FTPWELCOME, "r")) != NULL) {
609 #endif
610 		while (fgets(line, sizeof(line), fd) != NULL) {
611 			if ((cp = strchr(line, '\n')) != NULL)
612 				*cp = '\0';
613 			lreply(220, "%s", line);
614 		}
615 		(void) fflush(stdout);
616 		(void) fclose(fd);
617 		/* reply(220,) must follow */
618 	}
619 #ifndef VIRTUAL_HOSTING
620 	if ((hostname = malloc(MAXHOSTNAMELEN)) == NULL)
621 		fatalerror("Ran out of memory.");
622 	(void) gethostname(hostname, MAXHOSTNAMELEN - 1);
623 	hostname[MAXHOSTNAMELEN - 1] = '\0';
624 #endif
625 	if (hostinfo)
626 		reply(220, "%s FTP server (%s) ready.", hostname, version);
627 	else
628 		reply(220, "FTP server ready.");
629 	for (;;)
630 		(void) yyparse();
631 	/* NOTREACHED */
632 }
633 
634 static void
635 lostconn(int signo)
636 {
637 
638 	if (ftpdebug)
639 		syslog(LOG_DEBUG, "lost connection");
640 	dologout(1);
641 }
642 
643 static void
644 sigquit(int signo)
645 {
646 
647 	syslog(LOG_ERR, "got signal %d", signo);
648 	dologout(1);
649 }
650 
651 #ifdef VIRTUAL_HOSTING
652 /*
653  * read in virtual host tables (if they exist)
654  */
655 
656 static void
657 inithosts(void)
658 {
659 	int insert;
660 	size_t len;
661 	FILE *fp;
662 	char *cp, *mp, *line;
663 	char *hostname;
664 	char *vhost, *anonuser, *statfile, *welcome, *loginmsg;
665 	struct ftphost *hrp, *lhrp;
666 	struct addrinfo hints, *res, *ai;
667 
668 	/*
669 	 * Fill in the default host information
670 	 */
671 	if ((hostname = malloc(MAXHOSTNAMELEN)) == NULL)
672 		fatalerror("Ran out of memory.");
673 	if (gethostname(hostname, MAXHOSTNAMELEN) < 0)
674 		hostname[0] = '\0';
675 	hostname[MAXHOSTNAMELEN - 1] = '\0';
676 	if ((hrp = malloc(sizeof(struct ftphost))) == NULL)
677 		fatalerror("Ran out of memory.");
678 	hrp->hostname = hostname;
679 	hrp->hostinfo = NULL;
680 
681 	memset(&hints, 0, sizeof(hints));
682 	hints.ai_flags = AI_CANONNAME;
683 	hints.ai_family = AF_UNSPEC;
684 	if (getaddrinfo(hrp->hostname, NULL, &hints, &res) == 0)
685 		hrp->hostinfo = res;
686 	hrp->statfile = _PATH_FTPDSTATFILE;
687 	hrp->welcome  = _PATH_FTPWELCOME;
688 	hrp->loginmsg = _PATH_FTPLOGINMESG;
689 	hrp->anonuser = "ftp";
690 	hrp->next = NULL;
691 	thishost = firsthost = lhrp = hrp;
692 	if ((fp = fopen(_PATH_FTPHOSTS, "r")) != NULL) {
693 		int addrsize, gothost;
694 		void *addr;
695 		struct hostent *hp;
696 
697 		while ((line = fgetln(fp, &len)) != NULL) {
698 			int	i, hp_error;
699 
700 			/* skip comments */
701 			if (line[0] == '#')
702 				continue;
703 			if (line[len - 1] == '\n') {
704 				line[len - 1] = '\0';
705 				mp = NULL;
706 			} else {
707 				if ((mp = malloc(len + 1)) == NULL)
708 					fatalerror("Ran out of memory.");
709 				memcpy(mp, line, len);
710 				mp[len] = '\0';
711 				line = mp;
712 			}
713 			cp = strtok(line, " \t");
714 			/* skip empty lines */
715 			if (cp == NULL)
716 				goto nextline;
717 			vhost = cp;
718 
719 			/* set defaults */
720 			anonuser = "ftp";
721 			statfile = _PATH_FTPDSTATFILE;
722 			welcome  = _PATH_FTPWELCOME;
723 			loginmsg = _PATH_FTPLOGINMESG;
724 
725 			/*
726 			 * Preparse the line so we can use its info
727 			 * for all the addresses associated with
728 			 * the virtual host name.
729 			 * Field 0, the virtual host name, is special:
730 			 * it's already parsed off and will be strdup'ed
731 			 * later, after we know its canonical form.
732 			 */
733 			for (i = 1; i < 5 && (cp = strtok(NULL, " \t")); i++)
734 				if (*cp != '-' && (cp = strdup(cp)))
735 					switch (i) {
736 					case 1:	/* anon user permissions */
737 						anonuser = cp;
738 						break;
739 					case 2: /* statistics file */
740 						statfile = cp;
741 						break;
742 					case 3: /* welcome message */
743 						welcome  = cp;
744 						break;
745 					case 4: /* login message */
746 						loginmsg = cp;
747 						break;
748 					default: /* programming error */
749 						abort();
750 						/* NOTREACHED */
751 					}
752 
753 			hints.ai_flags = 0;
754 			hints.ai_family = AF_UNSPEC;
755 			hints.ai_flags = AI_PASSIVE;
756 			if (getaddrinfo(vhost, NULL, &hints, &res) != 0)
757 				goto nextline;
758 			for (ai = res; ai != NULL && ai->ai_addr != NULL;
759 			     ai = ai->ai_next) {
760 
761 			gothost = 0;
762 			for (hrp = firsthost; hrp != NULL; hrp = hrp->next) {
763 				struct addrinfo *hi;
764 
765 				for (hi = hrp->hostinfo; hi != NULL;
766 				     hi = hi->ai_next)
767 					if (hi->ai_addrlen == ai->ai_addrlen &&
768 					    memcmp(hi->ai_addr,
769 						   ai->ai_addr,
770 						   ai->ai_addr->sa_len) == 0) {
771 						gothost++;
772 						break;
773 					}
774 				if (gothost)
775 					break;
776 			}
777 			if (hrp == NULL) {
778 				if ((hrp = malloc(sizeof(struct ftphost))) == NULL)
779 					goto nextline;
780 				hrp->hostname = NULL;
781 				insert = 1;
782 			} else {
783 				if (hrp->hostinfo && hrp->hostinfo != res)
784 					freeaddrinfo(hrp->hostinfo);
785 				insert = 0; /* host already in the chain */
786 			}
787 			hrp->hostinfo = res;
788 
789 			/*
790 			 * determine hostname to use.
791 			 * force defined name if there is a valid alias
792 			 * otherwise fallback to primary hostname
793 			 */
794 			/* XXX: getaddrinfo() can't do alias check */
795 			switch(hrp->hostinfo->ai_family) {
796 			case AF_INET:
797 				addr = &((struct sockaddr_in *)hrp->hostinfo->ai_addr)->sin_addr;
798 				addrsize = sizeof(struct in_addr);
799 				break;
800 			case AF_INET6:
801 				addr = &((struct sockaddr_in6 *)hrp->hostinfo->ai_addr)->sin6_addr;
802 				addrsize = sizeof(struct in6_addr);
803 				break;
804 			default:
805 				/* should not reach here */
806 				freeaddrinfo(hrp->hostinfo);
807 				if (insert)
808 					free(hrp); /*not in chain, can free*/
809 				else
810 					hrp->hostinfo = NULL; /*mark as blank*/
811 				goto nextline;
812 				/* NOTREACHED */
813 			}
814 			if ((hp = getipnodebyaddr(addr, addrsize,
815 						  hrp->hostinfo->ai_family,
816 						  &hp_error)) != NULL) {
817 				if (strcmp(vhost, hp->h_name) != 0) {
818 					if (hp->h_aliases == NULL)
819 						vhost = hp->h_name;
820 					else {
821 						i = 0;
822 						while (hp->h_aliases[i] &&
823 						       strcmp(vhost, hp->h_aliases[i]) != 0)
824 							++i;
825 						if (hp->h_aliases[i] == NULL)
826 							vhost = hp->h_name;
827 					}
828 				}
829 			}
830 			if (hrp->hostname &&
831 			    strcmp(hrp->hostname, vhost) != 0) {
832 				free(hrp->hostname);
833 				hrp->hostname = NULL;
834 			}
835 			if (hrp->hostname == NULL &&
836 			    (hrp->hostname = strdup(vhost)) == NULL) {
837 				freeaddrinfo(hrp->hostinfo);
838 				hrp->hostinfo = NULL; /* mark as blank */
839 				if (hp)
840 					freehostent(hp);
841 				goto nextline;
842 			}
843 			hrp->anonuser = anonuser;
844 			hrp->statfile = statfile;
845 			hrp->welcome  = welcome;
846 			hrp->loginmsg = loginmsg;
847 			if (insert) {
848 				hrp->next  = NULL;
849 				lhrp->next = hrp;
850 				lhrp = hrp;
851 			}
852 			if (hp)
853 				freehostent(hp);
854 		      }
855 nextline:
856 			if (mp)
857 				free(mp);
858 		}
859 		(void) fclose(fp);
860 	}
861 }
862 
863 static void
864 selecthost(union sockunion *su)
865 {
866 	struct ftphost	*hrp;
867 	u_int16_t port;
868 #ifdef INET6
869 	struct in6_addr *mapped_in6 = NULL;
870 #endif
871 	struct addrinfo *hi;
872 
873 #ifdef INET6
874 	/*
875 	 * XXX IPv4 mapped IPv6 addr consideraton,
876 	 * specified in rfc2373.
877 	 */
878 	if (su->su_family == AF_INET6 &&
879 	    IN6_IS_ADDR_V4MAPPED(&su->su_sin6.sin6_addr))
880 		mapped_in6 = &su->su_sin6.sin6_addr;
881 #endif
882 
883 	hrp = thishost = firsthost;	/* default */
884 	port = su->su_port;
885 	su->su_port = 0;
886 	while (hrp != NULL) {
887 	    for (hi = hrp->hostinfo; hi != NULL; hi = hi->ai_next) {
888 		if (memcmp(su, hi->ai_addr, hi->ai_addrlen) == 0) {
889 			thishost = hrp;
890 			break;
891 		}
892 #ifdef INET6
893 		/* XXX IPv4 mapped IPv6 addr consideraton */
894 		if (hi->ai_addr->sa_family == AF_INET && mapped_in6 != NULL &&
895 		    (memcmp(&mapped_in6->s6_addr[12],
896 			    &((struct sockaddr_in *)hi->ai_addr)->sin_addr,
897 			    sizeof(struct in_addr)) == 0)) {
898 			thishost = hrp;
899 			break;
900 		}
901 #endif
902 	    }
903 	    hrp = hrp->next;
904 	}
905 	su->su_port = port;
906 	/* setup static variables as appropriate */
907 	hostname = thishost->hostname;
908 	ftpuser = thishost->anonuser;
909 }
910 #endif
911 
912 /*
913  * Helper function for sgetpwnam().
914  */
915 static char *
916 sgetsave(char *s)
917 {
918 	char *new = malloc((unsigned) strlen(s) + 1);
919 
920 	if (new == NULL) {
921 		perror_reply(421, "Local resource failure: malloc");
922 		dologout(1);
923 		/* NOTREACHED */
924 	}
925 	(void) strcpy(new, s);
926 	return (new);
927 }
928 
929 /*
930  * Save the result of a getpwnam.  Used for USER command, since
931  * the data returned must not be clobbered by any other command
932  * (e.g., globbing).
933  */
934 static struct passwd *
935 sgetpwnam(char *name)
936 {
937 	static struct passwd save;
938 	struct passwd *p;
939 
940 	if ((p = getpwnam(name)) == NULL)
941 		return (p);
942 	if (save.pw_name) {
943 		free(save.pw_name);
944 		free(save.pw_passwd);
945 		free(save.pw_gecos);
946 		free(save.pw_dir);
947 		free(save.pw_shell);
948 	}
949 	save = *p;
950 	save.pw_name = sgetsave(p->pw_name);
951 	save.pw_passwd = sgetsave(p->pw_passwd);
952 	save.pw_gecos = sgetsave(p->pw_gecos);
953 	save.pw_dir = sgetsave(p->pw_dir);
954 	save.pw_shell = sgetsave(p->pw_shell);
955 	return (&save);
956 }
957 
958 static int login_attempts;	/* number of failed login attempts */
959 static int askpasswd;		/* had user command, ask for passwd */
960 static char curname[MAXLOGNAME];	/* current USER name */
961 
962 /*
963  * USER command.
964  * Sets global passwd pointer pw if named account exists and is acceptable;
965  * sets askpasswd if a PASS command is expected.  If logged in previously,
966  * need to reset state.  If name is "ftp" or "anonymous", the name is not in
967  * _PATH_FTPUSERS, and ftp account exists, set guest and pw, then just return.
968  * If account doesn't exist, ask for passwd anyway.  Otherwise, check user
969  * requesting login privileges.  Disallow anyone who does not have a standard
970  * shell as returned by getusershell().  Disallow anyone mentioned in the file
971  * _PATH_FTPUSERS to allow people such as root and uucp to be avoided.
972  */
973 void
974 user(char *name)
975 {
976 	char *cp, *shell;
977 
978 	if (logged_in) {
979 		if (guest) {
980 			reply(530, "Can't change user from guest login.");
981 			return;
982 		} else if (dochroot) {
983 			reply(530, "Can't change user from chroot user.");
984 			return;
985 		}
986 		end_login();
987 	}
988 
989 	guest = 0;
990 	if (strcmp(name, "ftp") == 0 || strcmp(name, "anonymous") == 0) {
991 		if (checkuser(_PATH_FTPUSERS, "ftp", 0, NULL) ||
992 		    checkuser(_PATH_FTPUSERS, "anonymous", 0, NULL))
993 			reply(530, "User %s access denied.", name);
994 #ifdef VIRTUAL_HOSTING
995 		else if ((pw = sgetpwnam(thishost->anonuser)) != NULL) {
996 #else
997 		else if ((pw = sgetpwnam("ftp")) != NULL) {
998 #endif
999 			guest = 1;
1000 			askpasswd = 1;
1001 			reply(331,
1002 			"Guest login ok, send your email address as password.");
1003 		} else
1004 			reply(530, "User %s unknown.", name);
1005 		if (!askpasswd && logging)
1006 			syslog(LOG_NOTICE,
1007 			    "ANONYMOUS FTP LOGIN REFUSED FROM %s", remotehost);
1008 		return;
1009 	}
1010 	if (anon_only != 0) {
1011 		reply(530, "Sorry, only anonymous ftp allowed.");
1012 		return;
1013 	}
1014 
1015 	if ((pw = sgetpwnam(name))) {
1016 		if ((shell = pw->pw_shell) == NULL || *shell == 0)
1017 			shell = _PATH_BSHELL;
1018 		setusershell();
1019 		while ((cp = getusershell()) != NULL)
1020 			if (strcmp(cp, shell) == 0)
1021 				break;
1022 		endusershell();
1023 
1024 		if (cp == NULL || checkuser(_PATH_FTPUSERS, name, 1, NULL)) {
1025 			reply(530, "User %s access denied.", name);
1026 			if (logging)
1027 				syslog(LOG_NOTICE,
1028 				    "FTP LOGIN REFUSED FROM %s, %s",
1029 				    remotehost, name);
1030 			pw = (struct passwd *) NULL;
1031 			return;
1032 		}
1033 	}
1034 	if (logging)
1035 		strncpy(curname, name, sizeof(curname)-1);
1036 
1037 	pwok = 0;
1038 #ifdef USE_PAM
1039 	/* XXX Kluge! The conversation mechanism needs to be fixed. */
1040 #endif
1041 	if (opiechallenge(&opiedata, name, opieprompt) == 0) {
1042 		pwok = (pw != NULL) &&
1043 		       opieaccessfile(remotehost) &&
1044 		       opiealways(pw->pw_dir);
1045 		reply(331, "Response to %s %s for %s.",
1046 		      opieprompt, pwok ? "requested" : "required", name);
1047 	} else {
1048 		pwok = 1;
1049 		reply(331, "Password required for %s.", name);
1050 	}
1051 	askpasswd = 1;
1052 	/*
1053 	 * Delay before reading passwd after first failed
1054 	 * attempt to slow down passwd-guessing programs.
1055 	 */
1056 	if (login_attempts)
1057 		sleep((unsigned) login_attempts);
1058 }
1059 
1060 /*
1061  * Check if a user is in the file "fname",
1062  * return a pointer to a malloc'd string with the rest
1063  * of the matching line in "residue" if not NULL.
1064  */
1065 static int
1066 checkuser(char *fname, char *name, int pwset, char **residue)
1067 {
1068 	FILE *fd;
1069 	int found = 0;
1070 	size_t len;
1071 	char *line, *mp, *p;
1072 
1073 	if ((fd = fopen(fname, "r")) != NULL) {
1074 		while (!found && (line = fgetln(fd, &len)) != NULL) {
1075 			/* skip comments */
1076 			if (line[0] == '#')
1077 				continue;
1078 			if (line[len - 1] == '\n') {
1079 				line[len - 1] = '\0';
1080 				mp = NULL;
1081 			} else {
1082 				if ((mp = malloc(len + 1)) == NULL)
1083 					fatalerror("Ran out of memory.");
1084 				memcpy(mp, line, len);
1085 				mp[len] = '\0';
1086 				line = mp;
1087 			}
1088 			/* avoid possible leading and trailing whitespace */
1089 			p = strtok(line, " \t");
1090 			/* skip empty lines */
1091 			if (p == NULL)
1092 				goto nextline;
1093 			/*
1094 			 * if first chr is '@', check group membership
1095 			 */
1096 			if (p[0] == '@') {
1097 				int i = 0;
1098 				struct group *grp;
1099 
1100 				if (p[1] == '\0') /* single @ matches anyone */
1101 					found = 1;
1102 				else {
1103 					if ((grp = getgrnam(p+1)) == NULL)
1104 						goto nextline;
1105 					/*
1106 					 * Check user's default group
1107 					 */
1108 					if (pwset && grp->gr_gid == pw->pw_gid)
1109 						found = 1;
1110 					/*
1111 					 * Check supplementary groups
1112 					 */
1113 					while (!found && grp->gr_mem[i])
1114 						found = strcmp(name,
1115 							grp->gr_mem[i++])
1116 							== 0;
1117 				}
1118 			}
1119 			/*
1120 			 * Otherwise, just check for username match
1121 			 */
1122 			else
1123 				found = strcmp(p, name) == 0;
1124 			/*
1125 			 * Save the rest of line to "residue" if matched
1126 			 */
1127 			if (found && residue) {
1128 				if ((p = strtok(NULL, "")) != NULL)
1129 					p += strspn(p, " \t");
1130 				if (p && *p) {
1131 				 	if ((*residue = strdup(p)) == NULL)
1132 						fatalerror("Ran out of memory.");
1133 				} else
1134 					*residue = NULL;
1135 			}
1136 nextline:
1137 			if (mp)
1138 				free(mp);
1139 		}
1140 		(void) fclose(fd);
1141 	}
1142 	return (found);
1143 }
1144 
1145 /*
1146  * Terminate login as previous user, if any, resetting state;
1147  * used when USER command is given or login fails.
1148  */
1149 static void
1150 end_login(void)
1151 {
1152 #ifdef USE_PAM
1153 	int e;
1154 #endif
1155 
1156 	(void) seteuid((uid_t)0);
1157 	if (logged_in && dowtmp)
1158 		ftpd_logwtmp(ttyline, "", NULL);
1159 	pw = NULL;
1160 #ifdef	LOGIN_CAP
1161 	setusercontext(NULL, getpwuid(0), (uid_t)0,
1162 		       LOGIN_SETPRIORITY|LOGIN_SETRESOURCES|LOGIN_SETUMASK|
1163 		       LOGIN_SETMAC);
1164 #endif
1165 #ifdef USE_PAM
1166 	if ((e = pam_setcred(pamh, PAM_DELETE_CRED)) != PAM_SUCCESS)
1167 		syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, e));
1168 	if ((e = pam_close_session(pamh,0)) != PAM_SUCCESS)
1169 		syslog(LOG_ERR, "pam_close_session: %s", pam_strerror(pamh, e));
1170 	if ((e = pam_end(pamh, e)) != PAM_SUCCESS)
1171 		syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1172 	pamh = NULL;
1173 #endif
1174 	logged_in = 0;
1175 	guest = 0;
1176 	dochroot = 0;
1177 }
1178 
1179 #ifdef USE_PAM
1180 
1181 /*
1182  * the following code is stolen from imap-uw PAM authentication module and
1183  * login.c
1184  */
1185 #define COPY_STRING(s) (s ? strdup(s) : NULL)
1186 
1187 struct cred_t {
1188 	const char *uname;		/* user name */
1189 	const char *pass;		/* password */
1190 };
1191 typedef struct cred_t cred_t;
1192 
1193 static int
1194 auth_conv(int num_msg, const struct pam_message **msg,
1195 	  struct pam_response **resp, void *appdata)
1196 {
1197 	int i;
1198 	cred_t *cred = (cred_t *) appdata;
1199 	struct pam_response *reply;
1200 
1201 	reply = calloc(num_msg, sizeof *reply);
1202 	if (reply == NULL)
1203 		return PAM_BUF_ERR;
1204 
1205 	for (i = 0; i < num_msg; i++) {
1206 		switch (msg[i]->msg_style) {
1207 		case PAM_PROMPT_ECHO_ON:	/* assume want user name */
1208 			reply[i].resp_retcode = PAM_SUCCESS;
1209 			reply[i].resp = COPY_STRING(cred->uname);
1210 			/* PAM frees resp. */
1211 			break;
1212 		case PAM_PROMPT_ECHO_OFF:	/* assume want password */
1213 			reply[i].resp_retcode = PAM_SUCCESS;
1214 			reply[i].resp = COPY_STRING(cred->pass);
1215 			/* PAM frees resp. */
1216 			break;
1217 		case PAM_TEXT_INFO:
1218 		case PAM_ERROR_MSG:
1219 			reply[i].resp_retcode = PAM_SUCCESS;
1220 			reply[i].resp = NULL;
1221 			break;
1222 		default:			/* unknown message style */
1223 			free(reply);
1224 			return PAM_CONV_ERR;
1225 		}
1226 	}
1227 
1228 	*resp = reply;
1229 	return PAM_SUCCESS;
1230 }
1231 
1232 /*
1233  * Attempt to authenticate the user using PAM.  Returns 0 if the user is
1234  * authenticated, or 1 if not authenticated.  If some sort of PAM system
1235  * error occurs (e.g., the "/etc/pam.conf" file is missing) then this
1236  * function returns -1.  This can be used as an indication that we should
1237  * fall back to a different authentication mechanism.
1238  */
1239 static int
1240 auth_pam(struct passwd **ppw, const char *pass)
1241 {
1242 	pam_handle_t *pamh = NULL;
1243 	const char *tmpl_user;
1244 	const void *item;
1245 	int rval;
1246 	int e;
1247 	cred_t auth_cred = { (*ppw)->pw_name, pass };
1248 	struct pam_conv conv = { &auth_conv, &auth_cred };
1249 
1250 	e = pam_start("ftpd", (*ppw)->pw_name, &conv, &pamh);
1251 	if (e != PAM_SUCCESS) {
1252 		syslog(LOG_ERR, "pam_start: %s", pam_strerror(pamh, e));
1253 		return -1;
1254 	}
1255 
1256 	e = pam_set_item(pamh, PAM_RHOST, remotehost);
1257 	if (e != PAM_SUCCESS) {
1258 		syslog(LOG_ERR, "pam_set_item(PAM_RHOST): %s",
1259 			pam_strerror(pamh, e));
1260 		return -1;
1261 	}
1262 
1263 	e = pam_authenticate(pamh, 0);
1264 	switch (e) {
1265 	case PAM_SUCCESS:
1266 		/*
1267 		 * With PAM we support the concept of a "template"
1268 		 * user.  The user enters a login name which is
1269 		 * authenticated by PAM, usually via a remote service
1270 		 * such as RADIUS or TACACS+.  If authentication
1271 		 * succeeds, a different but related "template" name
1272 		 * is used for setting the credentials, shell, and
1273 		 * home directory.  The name the user enters need only
1274 		 * exist on the remote authentication server, but the
1275 		 * template name must be present in the local password
1276 		 * database.
1277 		 *
1278 		 * This is supported by two various mechanisms in the
1279 		 * individual modules.  However, from the application's
1280 		 * point of view, the template user is always passed
1281 		 * back as a changed value of the PAM_USER item.
1282 		 */
1283 		if ((e = pam_get_item(pamh, PAM_USER, &item)) ==
1284 		    PAM_SUCCESS) {
1285 			tmpl_user = (const char *) item;
1286 			if (strcmp((*ppw)->pw_name, tmpl_user) != 0)
1287 				*ppw = getpwnam(tmpl_user);
1288 		} else
1289 			syslog(LOG_ERR, "Couldn't get PAM_USER: %s",
1290 			    pam_strerror(pamh, e));
1291 		rval = 0;
1292 		break;
1293 
1294 	case PAM_AUTH_ERR:
1295 	case PAM_USER_UNKNOWN:
1296 	case PAM_MAXTRIES:
1297 		rval = 1;
1298 		break;
1299 
1300 	default:
1301 		syslog(LOG_ERR, "pam_authenticate: %s", pam_strerror(pamh, e));
1302 		rval = -1;
1303 		break;
1304 	}
1305 
1306 	if (rval == 0) {
1307 		e = pam_acct_mgmt(pamh, 0);
1308 		if (e == PAM_NEW_AUTHTOK_REQD) {
1309 			e = pam_chauthtok(pamh, PAM_CHANGE_EXPIRED_AUTHTOK);
1310 			if (e != PAM_SUCCESS) {
1311 				syslog(LOG_ERR, "pam_chauthtok: %s", pam_strerror(pamh, e));
1312 				rval = 1;
1313 			}
1314 		} else if (e != PAM_SUCCESS) {
1315 			rval = 1;
1316 		}
1317 	}
1318 
1319 	if (rval != 0) {
1320 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
1321 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1322 		}
1323 		pamh = NULL;
1324 	}
1325 	return rval;
1326 }
1327 
1328 #endif /* USE_PAM */
1329 
1330 void
1331 pass(char *passwd)
1332 {
1333 	int rval;
1334 	FILE *fd;
1335 #ifdef	LOGIN_CAP
1336 	login_cap_t *lc = NULL;
1337 #endif
1338 #ifdef USE_PAM
1339 	int e;
1340 #endif
1341 	char *chrootdir;
1342 	char *residue = NULL;
1343 	char *xpasswd;
1344 
1345 	if (logged_in || askpasswd == 0) {
1346 		reply(503, "Login with USER first.");
1347 		return;
1348 	}
1349 	askpasswd = 0;
1350 	if (!guest) {		/* "ftp" is only account allowed no password */
1351 		if (pw == NULL) {
1352 			rval = 1;	/* failure below */
1353 			goto skip;
1354 		}
1355 #ifdef USE_PAM
1356 		rval = auth_pam(&pw, passwd);
1357 		if (rval >= 0) {
1358 			opieunlock();
1359 			goto skip;
1360 		}
1361 #endif
1362 		if (opieverify(&opiedata, passwd) == 0)
1363 			xpasswd = pw->pw_passwd;
1364 		else if (pwok) {
1365 			xpasswd = crypt(passwd, pw->pw_passwd);
1366 			if (passwd[0] == '\0' && pw->pw_passwd[0] != '\0')
1367 				xpasswd = ":";
1368 		} else {
1369 			rval = 1;
1370 			goto skip;
1371 		}
1372 		rval = strcmp(pw->pw_passwd, xpasswd);
1373 		if (pw->pw_expire && time(NULL) >= pw->pw_expire)
1374 			rval = 1;	/* failure */
1375 skip:
1376 		/*
1377 		 * If rval == 1, the user failed the authentication check
1378 		 * above.  If rval == 0, either PAM or local authentication
1379 		 * succeeded.
1380 		 */
1381 		if (rval) {
1382 			reply(530, "Login incorrect.");
1383 			if (logging) {
1384 				syslog(LOG_NOTICE,
1385 				    "FTP LOGIN FAILED FROM %s",
1386 				    remotehost);
1387 				syslog(LOG_AUTHPRIV | LOG_NOTICE,
1388 				    "FTP LOGIN FAILED FROM %s, %s",
1389 				    remotehost, curname);
1390 			}
1391 			pw = NULL;
1392 			if (login_attempts++ >= 5) {
1393 				syslog(LOG_NOTICE,
1394 				    "repeated login failures from %s",
1395 				    remotehost);
1396 				exit(0);
1397 			}
1398 			return;
1399 		}
1400 	}
1401 	login_attempts = 0;		/* this time successful */
1402 	if (setegid((gid_t)pw->pw_gid) < 0) {
1403 		reply(550, "Can't set gid.");
1404 		return;
1405 	}
1406 	/* May be overridden by login.conf */
1407 	(void) umask(defumask);
1408 #ifdef	LOGIN_CAP
1409 	if ((lc = login_getpwclass(pw)) != NULL) {
1410 		char	remote_ip[MAXHOSTNAMELEN];
1411 
1412 		getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
1413 			remote_ip, sizeof(remote_ip) - 1, NULL, 0,
1414 			NI_NUMERICHOST);
1415 		remote_ip[sizeof(remote_ip) - 1] = 0;
1416 		if (!auth_hostok(lc, remotehost, remote_ip)) {
1417 			syslog(LOG_INFO|LOG_AUTH,
1418 			    "FTP LOGIN FAILED (HOST) as %s: permission denied.",
1419 			    pw->pw_name);
1420 			reply(530, "Permission denied.\n");
1421 			pw = NULL;
1422 			return;
1423 		}
1424 		if (!auth_timeok(lc, time(NULL))) {
1425 			reply(530, "Login not available right now.\n");
1426 			pw = NULL;
1427 			return;
1428 		}
1429 	}
1430 	setusercontext(lc, pw, (uid_t)0,
1431 		LOGIN_SETLOGIN|LOGIN_SETGROUP|LOGIN_SETPRIORITY|
1432 		LOGIN_SETRESOURCES|LOGIN_SETUMASK|LOGIN_SETMAC);
1433 #else
1434 	setlogin(pw->pw_name);
1435 	(void) initgroups(pw->pw_name, pw->pw_gid);
1436 #endif
1437 
1438 #ifdef USE_PAM
1439 	if (pamh) {
1440 		if ((e = pam_open_session(pamh, 0)) != PAM_SUCCESS) {
1441 			syslog(LOG_ERR, "pam_open_session: %s", pam_strerror(pamh, e));
1442 		} else if ((e = pam_setcred(pamh, PAM_ESTABLISH_CRED)) != PAM_SUCCESS) {
1443 			syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, e));
1444 		}
1445 	}
1446 #endif
1447 
1448 	/* open wtmp before chroot */
1449 	if (dowtmp)
1450 		ftpd_logwtmp(ttyline, pw->pw_name,
1451 		    (struct sockaddr *)&his_addr);
1452 	logged_in = 1;
1453 
1454 	if (guest && stats && statfd < 0)
1455 #ifdef VIRTUAL_HOSTING
1456 		if ((statfd = open(thishost->statfile, O_WRONLY|O_APPEND)) < 0)
1457 #else
1458 		if ((statfd = open(_PATH_FTPDSTATFILE, O_WRONLY|O_APPEND)) < 0)
1459 #endif
1460 			stats = 0;
1461 
1462 	dochroot =
1463 		checkuser(_PATH_FTPCHROOT, pw->pw_name, 1, &residue)
1464 #ifdef	LOGIN_CAP	/* Allow login.conf configuration as well */
1465 		|| login_getcapbool(lc, "ftp-chroot", 0)
1466 #endif
1467 	;
1468 	chrootdir = NULL;
1469 	/*
1470 	 * For a chrooted local user,
1471 	 * a) see whether ftpchroot(5) specifies a chroot directory,
1472 	 * b) extract the directory pathname from the line,
1473 	 * c) expand it to the absolute pathname if necessary.
1474 	 */
1475 	if (dochroot && residue &&
1476 	    (chrootdir = strtok(residue, " \t")) != NULL) {
1477 		if (chrootdir[0] != '/')
1478 			asprintf(&chrootdir, "%s/%s", pw->pw_dir, chrootdir);
1479 		else
1480 			chrootdir = strdup(chrootdir); /* so it can be freed */
1481 		if (chrootdir == NULL)
1482 			fatalerror("Ran out of memory.");
1483 	}
1484 	if (guest || dochroot) {
1485 		/*
1486 		 * If no chroot directory set yet, use the login directory.
1487 		 * Copy it so it can be modified while pw->pw_dir stays intact.
1488 		 */
1489 		if (chrootdir == NULL &&
1490 		    (chrootdir = strdup(pw->pw_dir)) == NULL)
1491 			fatalerror("Ran out of memory.");
1492 		/*
1493 		 * Check for the "/chroot/./home" syntax,
1494 		 * separate the chroot and home directory pathnames.
1495 		 */
1496 		if ((homedir = strstr(chrootdir, "/./")) != NULL) {
1497 			*(homedir++) = '\0';	/* wipe '/' */
1498 			homedir++;		/* skip '.' */
1499 			/* so chrootdir can be freed later */
1500 			if ((homedir = strdup(homedir)) == NULL)
1501 				fatalerror("Ran out of memory.");
1502 		} else {
1503 			/*
1504 			 * We MUST do a chdir() after the chroot. Otherwise
1505 			 * the old current directory will be accessible as "."
1506 			 * outside the new root!
1507 			 */
1508 			homedir = "/";
1509 		}
1510 		/*
1511 		 * Finally, do chroot()
1512 		 */
1513 		if (chroot(chrootdir) < 0) {
1514 			reply(550, "Can't change root.");
1515 			goto bad;
1516 		}
1517 	} else	/* real user w/o chroot */
1518 		homedir = pw->pw_dir;
1519 	/*
1520 	 * Set euid *before* doing chdir() so
1521 	 * a) the user won't be carried to a directory that he couldn't reach
1522 	 *    on his own due to no permission to upper path components,
1523 	 * b) NFS mounted homedirs w/restrictive permissions will be accessible
1524 	 *    (uid 0 has no root power over NFS if not mapped explicitly.)
1525 	 */
1526 	if (seteuid((uid_t)pw->pw_uid) < 0) {
1527 		reply(550, "Can't set uid.");
1528 		goto bad;
1529 	}
1530 	if (chdir(homedir) < 0) {
1531 		if (guest || dochroot) {
1532 			reply(550, "Can't change to base directory.");
1533 			goto bad;
1534 		} else {
1535 			if (chdir("/") < 0) {
1536 				reply(550, "Root is inaccessible.");
1537 				goto bad;
1538 			}
1539 			lreply(230, "No directory! Logging in with home=/");
1540 		}
1541 	}
1542 
1543 	/*
1544 	 * Display a login message, if it exists.
1545 	 * N.B. reply(230,) must follow the message.
1546 	 */
1547 #ifdef VIRTUAL_HOSTING
1548 	if ((fd = fopen(thishost->loginmsg, "r")) != NULL) {
1549 #else
1550 	if ((fd = fopen(_PATH_FTPLOGINMESG, "r")) != NULL) {
1551 #endif
1552 		char *cp, line[LINE_MAX];
1553 
1554 		while (fgets(line, sizeof(line), fd) != NULL) {
1555 			if ((cp = strchr(line, '\n')) != NULL)
1556 				*cp = '\0';
1557 			lreply(230, "%s", line);
1558 		}
1559 		(void) fflush(stdout);
1560 		(void) fclose(fd);
1561 	}
1562 	if (guest) {
1563 		if (ident != NULL)
1564 			free(ident);
1565 		ident = strdup(passwd);
1566 		if (ident == NULL)
1567 			fatalerror("Ran out of memory.");
1568 
1569 		reply(230, "Guest login ok, access restrictions apply.");
1570 #ifdef SETPROCTITLE
1571 #ifdef VIRTUAL_HOSTING
1572 		if (thishost != firsthost)
1573 			snprintf(proctitle, sizeof(proctitle),
1574 				 "%s: anonymous(%s)/%s", remotehost, hostname,
1575 				 passwd);
1576 		else
1577 #endif
1578 			snprintf(proctitle, sizeof(proctitle),
1579 				 "%s: anonymous/%s", remotehost, passwd);
1580 		setproctitle("%s", proctitle);
1581 #endif /* SETPROCTITLE */
1582 		if (logging)
1583 			syslog(LOG_INFO, "ANONYMOUS FTP LOGIN FROM %s, %s",
1584 			    remotehost, passwd);
1585 	} else {
1586 		if (dochroot)
1587 			reply(230, "User %s logged in, "
1588 				   "access restrictions apply.", pw->pw_name);
1589 		else
1590 			reply(230, "User %s logged in.", pw->pw_name);
1591 
1592 #ifdef SETPROCTITLE
1593 		snprintf(proctitle, sizeof(proctitle),
1594 			 "%s: user/%s", remotehost, pw->pw_name);
1595 		setproctitle("%s", proctitle);
1596 #endif /* SETPROCTITLE */
1597 		if (logging)
1598 			syslog(LOG_INFO, "FTP LOGIN FROM %s as %s",
1599 			    remotehost, pw->pw_name);
1600 	}
1601 #ifdef	LOGIN_CAP
1602 	login_close(lc);
1603 #endif
1604 	if (chrootdir)
1605 		free(chrootdir);
1606 	if (residue)
1607 		free(residue);
1608 	return;
1609 bad:
1610 	/* Forget all about it... */
1611 #ifdef	LOGIN_CAP
1612 	login_close(lc);
1613 #endif
1614 	if (chrootdir)
1615 		free(chrootdir);
1616 	if (residue)
1617 		free(residue);
1618 	end_login();
1619 }
1620 
1621 void
1622 retrieve(char *cmd, char *name)
1623 {
1624 	FILE *fin, *dout;
1625 	struct stat st;
1626 	int (*closefunc)(FILE *);
1627 	time_t start;
1628 
1629 	if (cmd == 0) {
1630 		fin = fopen(name, "r"), closefunc = fclose;
1631 		st.st_size = 0;
1632 	} else {
1633 		char line[BUFSIZ];
1634 
1635 		(void) snprintf(line, sizeof(line), cmd, name), name = line;
1636 		fin = ftpd_popen(line, "r"), closefunc = ftpd_pclose;
1637 		st.st_size = -1;
1638 		st.st_blksize = BUFSIZ;
1639 	}
1640 	if (fin == NULL) {
1641 		if (errno != 0) {
1642 			perror_reply(550, name);
1643 			if (cmd == 0) {
1644 				LOGCMD("get", name);
1645 			}
1646 		}
1647 		return;
1648 	}
1649 	byte_count = -1;
1650 	if (cmd == 0) {
1651 		if (fstat(fileno(fin), &st) < 0) {
1652 			perror_reply(550, name);
1653 			goto done;
1654 		}
1655 		if (!S_ISREG(st.st_mode)) {
1656 			if (guest) {
1657 				reply(550, "%s: not a plain file.", name);
1658 				goto done;
1659 			}
1660 			st.st_size = -1;
1661 			/* st.st_blksize is set for all descriptor types */
1662 		}
1663 	}
1664 	if (restart_point) {
1665 		if (type == TYPE_A) {
1666 			off_t i, n;
1667 			int c;
1668 
1669 			n = restart_point;
1670 			i = 0;
1671 			while (i++ < n) {
1672 				if ((c=getc(fin)) == EOF) {
1673 					perror_reply(550, name);
1674 					goto done;
1675 				}
1676 				if (c == '\n')
1677 					i++;
1678 			}
1679 		} else if (lseek(fileno(fin), restart_point, L_SET) < 0) {
1680 			perror_reply(550, name);
1681 			goto done;
1682 		}
1683 	}
1684 	dout = dataconn(name, st.st_size, "w");
1685 	if (dout == NULL)
1686 		goto done;
1687 	time(&start);
1688 	send_data(fin, dout, st.st_blksize, st.st_size,
1689 		  restart_point == 0 && cmd == 0 && S_ISREG(st.st_mode));
1690 	if (cmd == 0 && guest && stats)
1691 		logxfer(name, st.st_size, start);
1692 	(void) fclose(dout);
1693 	data = -1;
1694 	pdata = -1;
1695 done:
1696 	if (cmd == 0)
1697 		LOGBYTES("get", name, byte_count);
1698 	(*closefunc)(fin);
1699 }
1700 
1701 void
1702 store(char *name, char *mode, int unique)
1703 {
1704 	int fd;
1705 	FILE *fout, *din;
1706 	int (*closefunc)(FILE *);
1707 
1708 	if (*mode == 'a') {		/* APPE */
1709 		if (unique) {
1710 			/* Programming error */
1711 			syslog(LOG_ERR, "Internal: unique flag to APPE");
1712 			unique = 0;
1713 		}
1714 		if (guest && noguestmod) {
1715 			reply(550, "Appending to existing file denied");
1716 			goto err;
1717 		}
1718 		restart_point = 0;	/* not affected by preceding REST */
1719 	}
1720 	if (unique)			/* STOU overrides REST */
1721 		restart_point = 0;
1722 	if (guest && noguestmod) {
1723 		if (restart_point) {	/* guest STOR w/REST */
1724 			reply(550, "Modifying existing file denied");
1725 			goto err;
1726 		} else			/* treat guest STOR as STOU */
1727 			unique = 1;
1728 	}
1729 
1730 	if (restart_point)
1731 		mode = "r+";	/* so ASCII manual seek can work */
1732 	if (unique) {
1733 		if ((fd = guniquefd(name, &name)) < 0)
1734 			goto err;
1735 		fout = fdopen(fd, mode);
1736 	} else
1737 		fout = fopen(name, mode);
1738 	closefunc = fclose;
1739 	if (fout == NULL) {
1740 		perror_reply(553, name);
1741 		goto err;
1742 	}
1743 	byte_count = -1;
1744 	if (restart_point) {
1745 		if (type == TYPE_A) {
1746 			off_t i, n;
1747 			int c;
1748 
1749 			n = restart_point;
1750 			i = 0;
1751 			while (i++ < n) {
1752 				if ((c=getc(fout)) == EOF) {
1753 					perror_reply(550, name);
1754 					goto done;
1755 				}
1756 				if (c == '\n')
1757 					i++;
1758 			}
1759 			/*
1760 			 * We must do this seek to "current" position
1761 			 * because we are changing from reading to
1762 			 * writing.
1763 			 */
1764 			if (fseeko(fout, (off_t)0, SEEK_CUR) < 0) {
1765 				perror_reply(550, name);
1766 				goto done;
1767 			}
1768 		} else if (lseek(fileno(fout), restart_point, L_SET) < 0) {
1769 			perror_reply(550, name);
1770 			goto done;
1771 		}
1772 	}
1773 	din = dataconn(name, (off_t)-1, "r");
1774 	if (din == NULL)
1775 		goto done;
1776 	if (receive_data(din, fout) == 0) {
1777 		if (unique)
1778 			reply(226, "Transfer complete (unique file name:%s).",
1779 			    name);
1780 		else
1781 			reply(226, "Transfer complete.");
1782 	}
1783 	(void) fclose(din);
1784 	data = -1;
1785 	pdata = -1;
1786 done:
1787 	LOGBYTES(*mode == 'a' ? "append" : "put", name, byte_count);
1788 	(*closefunc)(fout);
1789 	return;
1790 err:
1791 	LOGCMD(*mode == 'a' ? "append" : "put" , name);
1792 	return;
1793 }
1794 
1795 static FILE *
1796 getdatasock(char *mode)
1797 {
1798 	int on = 1, s, t, tries;
1799 
1800 	if (data >= 0)
1801 		return (fdopen(data, mode));
1802 	(void) seteuid((uid_t)0);
1803 
1804 	s = socket(data_dest.su_family, SOCK_STREAM, 0);
1805 	if (s < 0)
1806 		goto bad;
1807 	if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
1808 		syslog(LOG_WARNING, "data setsockopt (SO_REUSEADDR): %m");
1809 	/* anchor socket to avoid multi-homing problems */
1810 	data_source = ctrl_addr;
1811 	data_source.su_port = htons(dataport);
1812 	for (tries = 1; ; tries++) {
1813 		if (bind(s, (struct sockaddr *)&data_source,
1814 		    data_source.su_len) >= 0)
1815 			break;
1816 		if (errno != EADDRINUSE || tries > 10)
1817 			goto bad;
1818 		sleep(tries);
1819 	}
1820 	(void) seteuid((uid_t)pw->pw_uid);
1821 #ifdef IP_TOS
1822 	if (data_source.su_family == AF_INET)
1823       {
1824 	on = IPTOS_THROUGHPUT;
1825 	if (setsockopt(s, IPPROTO_IP, IP_TOS, &on, sizeof(int)) < 0)
1826 		syslog(LOG_WARNING, "data setsockopt (IP_TOS): %m");
1827       }
1828 #endif
1829 #ifdef TCP_NOPUSH
1830 	/*
1831 	 * Turn off push flag to keep sender TCP from sending short packets
1832 	 * at the boundaries of each write().  Should probably do a SO_SNDBUF
1833 	 * to set the send buffer size as well, but that may not be desirable
1834 	 * in heavy-load situations.
1835 	 */
1836 	on = 1;
1837 	if (setsockopt(s, IPPROTO_TCP, TCP_NOPUSH, &on, sizeof on) < 0)
1838 		syslog(LOG_WARNING, "data setsockopt (TCP_NOPUSH): %m");
1839 #endif
1840 #ifdef SO_SNDBUF
1841 	on = 65536;
1842 	if (setsockopt(s, SOL_SOCKET, SO_SNDBUF, &on, sizeof on) < 0)
1843 		syslog(LOG_WARNING, "data setsockopt (SO_SNDBUF): %m");
1844 #endif
1845 
1846 	return (fdopen(s, mode));
1847 bad:
1848 	/* Return the real value of errno (close may change it) */
1849 	t = errno;
1850 	(void) seteuid((uid_t)pw->pw_uid);
1851 	(void) close(s);
1852 	errno = t;
1853 	return (NULL);
1854 }
1855 
1856 static FILE *
1857 dataconn(char *name, off_t size, char *mode)
1858 {
1859 	char sizebuf[32];
1860 	FILE *file;
1861 	int retry = 0, tos, conerrno;
1862 
1863 	file_size = size;
1864 	byte_count = 0;
1865 	if (size != (off_t) -1)
1866 		(void) snprintf(sizebuf, sizeof(sizebuf), " (%qd bytes)", size);
1867 	else
1868 		*sizebuf = '\0';
1869 	if (pdata >= 0) {
1870 		union sockunion from;
1871 		int flags;
1872 		int s, fromlen = ctrl_addr.su_len;
1873 		struct timeval timeout;
1874 		fd_set set;
1875 
1876 		FD_ZERO(&set);
1877 		FD_SET(pdata, &set);
1878 
1879 		timeout.tv_usec = 0;
1880 		timeout.tv_sec = 120;
1881 
1882 		/*
1883 		 * Granted a socket is in the blocking I/O mode,
1884 		 * accept() will block after a successful select()
1885 		 * if the selected connection dies in between.
1886 		 * Therefore set the non-blocking I/O flag here.
1887 		 */
1888 		if ((flags = fcntl(pdata, F_GETFL, 0)) == -1 ||
1889 		    fcntl(pdata, F_SETFL, flags | O_NONBLOCK) == -1)
1890 			goto pdata_err;
1891 		if (select(pdata+1, &set, (fd_set *) 0, (fd_set *) 0, &timeout) <= 0 ||
1892 		    (s = accept(pdata, (struct sockaddr *) &from, &fromlen)) < 0)
1893 			goto pdata_err;
1894 		(void) close(pdata);
1895 		pdata = s;
1896 		/*
1897 		 * Unset the inherited non-blocking I/O flag
1898 		 * on the child socket so stdio can work on it.
1899 		 */
1900 		if ((flags = fcntl(pdata, F_GETFL, 0)) == -1 ||
1901 		    fcntl(pdata, F_SETFL, flags & ~O_NONBLOCK) == -1)
1902 			goto pdata_err;
1903 #ifdef IP_TOS
1904 		if (from.su_family == AF_INET)
1905 	      {
1906 		tos = IPTOS_THROUGHPUT;
1907 		if (setsockopt(s, IPPROTO_IP, IP_TOS, &tos, sizeof(int)) < 0)
1908 			syslog(LOG_WARNING, "pdata setsockopt (IP_TOS): %m");
1909 	      }
1910 #endif
1911 		reply(150, "Opening %s mode data connection for '%s'%s.",
1912 		     type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
1913 		return (fdopen(pdata, mode));
1914 pdata_err:
1915 		reply(425, "Can't open data connection.");
1916 		(void) close(pdata);
1917 		pdata = -1;
1918 		return (NULL);
1919 	}
1920 	if (data >= 0) {
1921 		reply(125, "Using existing data connection for '%s'%s.",
1922 		    name, sizebuf);
1923 		usedefault = 1;
1924 		return (fdopen(data, mode));
1925 	}
1926 	if (usedefault)
1927 		data_dest = his_addr;
1928 	usedefault = 1;
1929 	do {
1930 		file = getdatasock(mode);
1931 		if (file == NULL) {
1932 			char hostbuf[BUFSIZ], portbuf[BUFSIZ];
1933 			getnameinfo((struct sockaddr *)&data_source,
1934 				data_source.su_len, hostbuf, sizeof(hostbuf) - 1,
1935 				portbuf, sizeof(portbuf),
1936 				NI_NUMERICHOST|NI_NUMERICSERV);
1937 			reply(425, "Can't create data socket (%s,%s): %s.",
1938 				hostbuf, portbuf, strerror(errno));
1939 			return (NULL);
1940 		}
1941 		data = fileno(file);
1942 		conerrno = 0;
1943 		if (connect(data, (struct sockaddr *)&data_dest,
1944 		    data_dest.su_len) == 0)
1945 			break;
1946 		conerrno = errno;
1947 		(void) fclose(file);
1948 		data = -1;
1949 		if (conerrno == EADDRINUSE) {
1950 			sleep((unsigned) swaitint);
1951 			retry += swaitint;
1952 		} else {
1953 			break;
1954 		}
1955 	} while (retry <= swaitmax);
1956 	if (conerrno != 0) {
1957 		perror_reply(425, "Can't build data connection");
1958 		return (NULL);
1959 	}
1960 	reply(150, "Opening %s mode data connection for '%s'%s.",
1961 	     type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
1962 	return (file);
1963 }
1964 
1965 /*
1966  * Tranfer the contents of "instr" to "outstr" peer using the appropriate
1967  * encapsulation of the data subject to Mode, Structure, and Type.
1968  *
1969  * NB: Form isn't handled.
1970  */
1971 static int
1972 send_data(FILE *instr, FILE *outstr, off_t blksize, off_t filesize, int isreg)
1973 {
1974 	int c, cp, filefd, netfd;
1975 	char *buf;
1976 	off_t cnt;
1977 
1978 	transflag++;
1979 	switch (type) {
1980 
1981 	case TYPE_A:
1982 		cp = '\0';
1983 		while ((c = getc(instr)) != EOF) {
1984 			if (recvurg)
1985 				goto got_oob;
1986 			byte_count++;
1987 			if (c == '\n' && cp != '\r') {
1988 				if (ferror(outstr))
1989 					goto data_err;
1990 				(void) putc('\r', outstr);
1991 			}
1992 			(void) putc(c, outstr);
1993 			cp = c;
1994 		}
1995 		if (recvurg)
1996 			goto got_oob;
1997 		fflush(outstr);
1998 		transflag = 0;
1999 		if (ferror(instr))
2000 			goto file_err;
2001 		if (ferror(outstr))
2002 			goto data_err;
2003 		reply(226, "Transfer complete.");
2004 		return (0);
2005 
2006 	case TYPE_I:
2007 	case TYPE_L:
2008 		/*
2009 		 * isreg is only set if we are not doing restart and we
2010 		 * are sending a regular file
2011 		 */
2012 		netfd = fileno(outstr);
2013 		filefd = fileno(instr);
2014 
2015 		if (isreg) {
2016 
2017 			off_t offset;
2018 			int err;
2019 
2020 			err = cnt = offset = 0;
2021 
2022 			while (err != -1 && filesize > 0) {
2023 				err = sendfile(filefd, netfd, offset, 0,
2024 					(struct sf_hdtr *) NULL, &cnt, 0);
2025 				/*
2026 				 * Calculate byte_count before OOB processing.
2027 				 * It can be used in myoob() later.
2028 				 */
2029 				byte_count += cnt;
2030 				if (recvurg)
2031 					goto got_oob;
2032 				offset += cnt;
2033 				filesize -= cnt;
2034 
2035 				if (err == -1) {
2036 					if (!cnt)
2037 						goto oldway;
2038 
2039 					goto data_err;
2040 				}
2041 			}
2042 
2043 			transflag = 0;
2044 			reply(226, "Transfer complete.");
2045 			return (0);
2046 		}
2047 
2048 oldway:
2049 		if ((buf = malloc((u_int)blksize)) == NULL) {
2050 			transflag = 0;
2051 			perror_reply(451, "Local resource failure: malloc");
2052 			return (-1);
2053 		}
2054 
2055 		while ((cnt = read(filefd, buf, (u_int)blksize)) > 0 &&
2056 		    write(netfd, buf, cnt) == cnt)
2057 			byte_count += cnt;
2058 		transflag = 0;
2059 		(void)free(buf);
2060 		if (cnt != 0) {
2061 			if (cnt < 0)
2062 				goto file_err;
2063 			goto data_err;
2064 		}
2065 		reply(226, "Transfer complete.");
2066 		return (0);
2067 	default:
2068 		transflag = 0;
2069 		reply(550, "Unimplemented TYPE %d in send_data", type);
2070 		return (-1);
2071 	}
2072 
2073 data_err:
2074 	transflag = 0;
2075 	perror_reply(426, "Data connection");
2076 	return (-1);
2077 
2078 file_err:
2079 	transflag = 0;
2080 	perror_reply(551, "Error on input file");
2081 	return (-1);
2082 
2083 got_oob:
2084 	myoob();
2085 	recvurg = 0;
2086 	transflag = 0;
2087 	return (-1);
2088 }
2089 
2090 /*
2091  * Transfer data from peer to "outstr" using the appropriate encapulation of
2092  * the data subject to Mode, Structure, and Type.
2093  *
2094  * N.B.: Form isn't handled.
2095  */
2096 static int
2097 receive_data(FILE *instr, FILE *outstr)
2098 {
2099 	int c;
2100 	int cnt, bare_lfs;
2101 	char buf[BUFSIZ];
2102 
2103 	transflag++;
2104 	bare_lfs = 0;
2105 
2106 	switch (type) {
2107 
2108 	case TYPE_I:
2109 	case TYPE_L:
2110 		while ((cnt = read(fileno(instr), buf, sizeof(buf))) > 0) {
2111 			if (recvurg)
2112 				goto got_oob;
2113 			if (write(fileno(outstr), buf, cnt) != cnt)
2114 				goto file_err;
2115 			byte_count += cnt;
2116 		}
2117 		if (recvurg)
2118 			goto got_oob;
2119 		if (cnt < 0)
2120 			goto data_err;
2121 		transflag = 0;
2122 		return (0);
2123 
2124 	case TYPE_E:
2125 		reply(553, "TYPE E not implemented.");
2126 		transflag = 0;
2127 		return (-1);
2128 
2129 	case TYPE_A:
2130 		while ((c = getc(instr)) != EOF) {
2131 			if (recvurg)
2132 				goto got_oob;
2133 			byte_count++;
2134 			if (c == '\n')
2135 				bare_lfs++;
2136 			while (c == '\r') {
2137 				if (ferror(outstr))
2138 					goto data_err;
2139 				if ((c = getc(instr)) != '\n') {
2140 					(void) putc ('\r', outstr);
2141 					if (c == '\0' || c == EOF)
2142 						goto contin2;
2143 				}
2144 			}
2145 			(void) putc(c, outstr);
2146 	contin2:	;
2147 		}
2148 		if (recvurg)
2149 			goto got_oob;
2150 		fflush(outstr);
2151 		if (ferror(instr))
2152 			goto data_err;
2153 		if (ferror(outstr))
2154 			goto file_err;
2155 		transflag = 0;
2156 		if (bare_lfs) {
2157 			lreply(226,
2158 		"WARNING! %d bare linefeeds received in ASCII mode",
2159 			    bare_lfs);
2160 		(void)printf("   File may not have transferred correctly.\r\n");
2161 		}
2162 		return (0);
2163 	default:
2164 		reply(550, "Unimplemented TYPE %d in receive_data", type);
2165 		transflag = 0;
2166 		return (-1);
2167 	}
2168 
2169 data_err:
2170 	transflag = 0;
2171 	perror_reply(426, "Data Connection");
2172 	return (-1);
2173 
2174 file_err:
2175 	transflag = 0;
2176 	perror_reply(452, "Error writing file");
2177 	return (-1);
2178 
2179 got_oob:
2180 	myoob();
2181 	recvurg = 0;
2182 	transflag = 0;
2183 	return (-1);
2184 }
2185 
2186 void
2187 statfilecmd(char *filename)
2188 {
2189 	FILE *fin;
2190 	int atstart;
2191 	int c;
2192 	char line[LINE_MAX];
2193 
2194 	(void)snprintf(line, sizeof(line), _PATH_LS " -lgA %s", filename);
2195 	fin = ftpd_popen(line, "r");
2196 	lreply(211, "status of %s:", filename);
2197 	atstart = 1;
2198 	while ((c = getc(fin)) != EOF) {
2199 		if (c == '\n') {
2200 			if (ferror(stdout)){
2201 				perror_reply(421, "control connection");
2202 				(void) ftpd_pclose(fin);
2203 				dologout(1);
2204 				/* NOTREACHED */
2205 			}
2206 			if (ferror(fin)) {
2207 				perror_reply(551, filename);
2208 				(void) ftpd_pclose(fin);
2209 				return;
2210 			}
2211 			(void) putc('\r', stdout);
2212 		}
2213 		/*
2214 		 * RFC 959 says neutral text should be prepended before
2215 		 * a leading 3-digit number followed by whitespace, but
2216 		 * many ftp clients can be confused by any leading digits,
2217 		 * as a matter of fact.
2218 		 */
2219 		if (atstart && isdigit(c))
2220 			(void) putc(' ', stdout);
2221 		(void) putc(c, stdout);
2222 		atstart = (c == '\n');
2223 	}
2224 	(void) ftpd_pclose(fin);
2225 	reply(211, "End of Status");
2226 }
2227 
2228 void
2229 statcmd(void)
2230 {
2231 	union sockunion *su;
2232 	u_char *a, *p;
2233 	char hname[NI_MAXHOST];
2234 	int ispassive;
2235 
2236 	if (hostinfo) {
2237 		lreply(211, "%s FTP server status:", hostname);
2238 		printf("     %s\r\n", version);
2239 	} else
2240 		lreply(211, "FTP server status:");
2241 	printf("     Connected to %s", remotehost);
2242 	if (!getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
2243 			 hname, sizeof(hname) - 1, NULL, 0, NI_NUMERICHOST)) {
2244 		if (strcmp(hname, remotehost) != 0)
2245 			printf(" (%s)", hname);
2246 	}
2247 	printf("\r\n");
2248 	if (logged_in) {
2249 		if (guest)
2250 			printf("     Logged in anonymously\r\n");
2251 		else
2252 			printf("     Logged in as %s\r\n", pw->pw_name);
2253 	} else if (askpasswd)
2254 		printf("     Waiting for password\r\n");
2255 	else
2256 		printf("     Waiting for user name\r\n");
2257 	printf("     TYPE: %s", typenames[type]);
2258 	if (type == TYPE_A || type == TYPE_E)
2259 		printf(", FORM: %s", formnames[form]);
2260 	if (type == TYPE_L)
2261 #if CHAR_BIT == 8
2262 		printf(" %d", CHAR_BIT);
2263 #else
2264 		printf(" %d", bytesize);	/* need definition! */
2265 #endif
2266 	printf("; STRUcture: %s; transfer MODE: %s\r\n",
2267 	    strunames[stru], modenames[mode]);
2268 	if (data != -1)
2269 		printf("     Data connection open\r\n");
2270 	else if (pdata != -1) {
2271 		ispassive = 1;
2272 		su = &pasv_addr;
2273 		goto printaddr;
2274 	} else if (usedefault == 0) {
2275 		ispassive = 0;
2276 		su = &data_dest;
2277 printaddr:
2278 #define UC(b) (((int) b) & 0xff)
2279 		if (epsvall) {
2280 			printf("     EPSV only mode (EPSV ALL)\r\n");
2281 			goto epsvonly;
2282 		}
2283 
2284 		/* PORT/PASV */
2285 		if (su->su_family == AF_INET) {
2286 			a = (u_char *) &su->su_sin.sin_addr;
2287 			p = (u_char *) &su->su_sin.sin_port;
2288 			printf("     %s (%d,%d,%d,%d,%d,%d)\r\n",
2289 				ispassive ? "PASV" : "PORT",
2290 				UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
2291 				UC(p[0]), UC(p[1]));
2292 		}
2293 
2294 		/* LPRT/LPSV */
2295 	    {
2296 		int alen, af, i;
2297 
2298 		switch (su->su_family) {
2299 		case AF_INET:
2300 			a = (u_char *) &su->su_sin.sin_addr;
2301 			p = (u_char *) &su->su_sin.sin_port;
2302 			alen = sizeof(su->su_sin.sin_addr);
2303 			af = 4;
2304 			break;
2305 		case AF_INET6:
2306 			a = (u_char *) &su->su_sin6.sin6_addr;
2307 			p = (u_char *) &su->su_sin6.sin6_port;
2308 			alen = sizeof(su->su_sin6.sin6_addr);
2309 			af = 6;
2310 			break;
2311 		default:
2312 			af = 0;
2313 			break;
2314 		}
2315 		if (af) {
2316 			printf("     %s (%d,%d,", ispassive ? "LPSV" : "LPRT",
2317 				af, alen);
2318 			for (i = 0; i < alen; i++)
2319 				printf("%d,", UC(a[i]));
2320 			printf("%d,%d,%d)\r\n", 2, UC(p[0]), UC(p[1]));
2321 		}
2322 	    }
2323 
2324 epsvonly:;
2325 		/* EPRT/EPSV */
2326 	    {
2327 		int af;
2328 
2329 		switch (su->su_family) {
2330 		case AF_INET:
2331 			af = 1;
2332 			break;
2333 		case AF_INET6:
2334 			af = 2;
2335 			break;
2336 		default:
2337 			af = 0;
2338 			break;
2339 		}
2340 		if (af) {
2341 			union sockunion tmp;
2342 
2343 			tmp = *su;
2344 			if (tmp.su_family == AF_INET6)
2345 				tmp.su_sin6.sin6_scope_id = 0;
2346 			if (!getnameinfo((struct sockaddr *)&tmp, tmp.su_len,
2347 					hname, sizeof(hname) - 1, NULL, 0,
2348 					NI_NUMERICHOST)) {
2349 				printf("     %s |%d|%s|%d|\r\n",
2350 					ispassive ? "EPSV" : "EPRT",
2351 					af, hname, htons(tmp.su_port));
2352 			}
2353 		}
2354 	    }
2355 #undef UC
2356 	} else
2357 		printf("     No data connection\r\n");
2358 	reply(211, "End of status");
2359 }
2360 
2361 void
2362 fatalerror(char *s)
2363 {
2364 
2365 	reply(451, "Error in server: %s\n", s);
2366 	reply(221, "Closing connection due to server error.");
2367 	dologout(0);
2368 	/* NOTREACHED */
2369 }
2370 
2371 void
2372 reply(int n, const char *fmt, ...)
2373 {
2374 	va_list ap;
2375 
2376 	va_start(ap, fmt);
2377 	(void)printf("%d ", n);
2378 	(void)vprintf(fmt, ap);
2379 	(void)printf("\r\n");
2380 	(void)fflush(stdout);
2381 	if (ftpdebug) {
2382 		syslog(LOG_DEBUG, "<--- %d ", n);
2383 		vsyslog(LOG_DEBUG, fmt, ap);
2384 	}
2385 }
2386 
2387 void
2388 lreply(int n, const char *fmt, ...)
2389 {
2390 	va_list ap;
2391 
2392 	va_start(ap, fmt);
2393 	(void)printf("%d- ", n);
2394 	(void)vprintf(fmt, ap);
2395 	(void)printf("\r\n");
2396 	(void)fflush(stdout);
2397 	if (ftpdebug) {
2398 		syslog(LOG_DEBUG, "<--- %d- ", n);
2399 		vsyslog(LOG_DEBUG, fmt, ap);
2400 	}
2401 }
2402 
2403 static void
2404 ack(char *s)
2405 {
2406 
2407 	reply(250, "%s command successful.", s);
2408 }
2409 
2410 void
2411 nack(char *s)
2412 {
2413 
2414 	reply(502, "%s command not implemented.", s);
2415 }
2416 
2417 /* ARGSUSED */
2418 void
2419 yyerror(char *s)
2420 {
2421 	char *cp;
2422 
2423 	if ((cp = strchr(cbuf,'\n')))
2424 		*cp = '\0';
2425 	reply(500, "'%s': command not understood.", cbuf);
2426 }
2427 
2428 void
2429 delete(char *name)
2430 {
2431 	struct stat st;
2432 
2433 	LOGCMD("delete", name);
2434 	if (lstat(name, &st) < 0) {
2435 		perror_reply(550, name);
2436 		return;
2437 	}
2438 	if ((st.st_mode&S_IFMT) == S_IFDIR) {
2439 		if (rmdir(name) < 0) {
2440 			perror_reply(550, name);
2441 			return;
2442 		}
2443 		goto done;
2444 	}
2445 	if ((guest && noguestmod) || unlink(name) < 0) {
2446 		perror_reply(550, name);
2447 		return;
2448 	}
2449 done:
2450 	ack("DELE");
2451 }
2452 
2453 void
2454 cwd(char *path)
2455 {
2456 
2457 	if (chdir(path) < 0)
2458 		perror_reply(550, path);
2459 	else
2460 		ack("CWD");
2461 }
2462 
2463 void
2464 makedir(char *name)
2465 {
2466 	char *s;
2467 
2468 	LOGCMD("mkdir", name);
2469 	if (guest && noguestmkd)
2470 		reply(550, "%s: permission denied", name);
2471 	else if (mkdir(name, 0777) < 0)
2472 		perror_reply(550, name);
2473 	else {
2474 		if ((s = doublequote(name)) == NULL)
2475 			fatalerror("Ran out of memory.");
2476 		reply(257, "\"%s\" directory created.", s);
2477 		free(s);
2478 	}
2479 }
2480 
2481 void
2482 removedir(char *name)
2483 {
2484 
2485 	LOGCMD("rmdir", name);
2486 	if (rmdir(name) < 0)
2487 		perror_reply(550, name);
2488 	else
2489 		ack("RMD");
2490 }
2491 
2492 void
2493 pwd(void)
2494 {
2495 	char *s, path[MAXPATHLEN + 1];
2496 
2497 	if (getwd(path) == (char *)NULL)
2498 		reply(550, "%s.", path);
2499 	else {
2500 		if ((s = doublequote(path)) == NULL)
2501 			fatalerror("Ran out of memory.");
2502 		reply(257, "\"%s\" is current directory.", s);
2503 		free(s);
2504 	}
2505 }
2506 
2507 char *
2508 renamefrom(char *name)
2509 {
2510 	struct stat st;
2511 
2512 	if (lstat(name, &st) < 0) {
2513 		perror_reply(550, name);
2514 		return ((char *)0);
2515 	}
2516 	reply(350, "File exists, ready for destination name");
2517 	return (name);
2518 }
2519 
2520 void
2521 renamecmd(char *from, char *to)
2522 {
2523 	struct stat st;
2524 
2525 	LOGCMD2("rename", from, to);
2526 
2527 	if (guest && (stat(to, &st) == 0)) {
2528 		reply(550, "%s: permission denied", to);
2529 		return;
2530 	}
2531 
2532 	if (rename(from, to) < 0)
2533 		perror_reply(550, "rename");
2534 	else
2535 		ack("RNTO");
2536 }
2537 
2538 static void
2539 dolog(struct sockaddr *who)
2540 {
2541 	int error;
2542 
2543 	realhostname_sa(remotehost, sizeof(remotehost) - 1, who, who->sa_len);
2544 
2545 #ifdef SETPROCTITLE
2546 #ifdef VIRTUAL_HOSTING
2547 	if (thishost != firsthost)
2548 		snprintf(proctitle, sizeof(proctitle), "%s: connected (to %s)",
2549 			 remotehost, hostname);
2550 	else
2551 #endif
2552 		snprintf(proctitle, sizeof(proctitle), "%s: connected",
2553 			 remotehost);
2554 	setproctitle("%s", proctitle);
2555 #endif /* SETPROCTITLE */
2556 
2557 	if (logging) {
2558 #ifdef VIRTUAL_HOSTING
2559 		if (thishost != firsthost)
2560 			syslog(LOG_INFO, "connection from %s (to %s)",
2561 			       remotehost, hostname);
2562 		else
2563 #endif
2564 		{
2565 			char	who_name[MAXHOSTNAMELEN];
2566 
2567 			error = getnameinfo(who, who->sa_len,
2568 					    who_name, sizeof(who_name) - 1,
2569 					    NULL, 0, NI_NUMERICHOST);
2570 			syslog(LOG_INFO, "connection from %s (%s)", remotehost,
2571 			       error == 0 ? who_name : "");
2572 		}
2573 	}
2574 }
2575 
2576 /*
2577  * Record logout in wtmp file
2578  * and exit with supplied status.
2579  */
2580 void
2581 dologout(int status)
2582 {
2583 	/*
2584 	 * Prevent reception of SIGURG from resulting in a resumption
2585 	 * back to the main program loop.
2586 	 */
2587 	transflag = 0;
2588 
2589 	if (logged_in && dowtmp) {
2590 		(void) seteuid((uid_t)0);
2591 		ftpd_logwtmp(ttyline, "", NULL);
2592 	}
2593 	/* beware of flushing buffers after a SIGPIPE */
2594 	_exit(status);
2595 }
2596 
2597 static void
2598 sigurg(int signo)
2599 {
2600 
2601 	recvurg = 1;
2602 }
2603 
2604 static void
2605 myoob(void)
2606 {
2607 	char *cp;
2608 
2609 	/* only process if transfer occurring */
2610 	if (!transflag)
2611 		return;
2612 	cp = tmpline;
2613 	if (getline(cp, 7, stdin) == NULL) {
2614 		reply(221, "You could at least say goodbye.");
2615 		dologout(0);
2616 	}
2617 	upper(cp);
2618 	if (strcmp(cp, "ABOR\r\n") == 0) {
2619 		tmpline[0] = '\0';
2620 		reply(426, "Transfer aborted. Data connection closed.");
2621 		reply(226, "Abort successful");
2622 	}
2623 	if (strcmp(cp, "STAT\r\n") == 0) {
2624 		tmpline[0] = '\0';
2625 		if (file_size != (off_t) -1)
2626 			reply(213, "Status: %qd of %qd bytes transferred",
2627 			    byte_count, file_size);
2628 		else
2629 			reply(213, "Status: %qd bytes transferred", byte_count);
2630 	}
2631 }
2632 
2633 /*
2634  * Note: a response of 425 is not mentioned as a possible response to
2635  *	the PASV command in RFC959. However, it has been blessed as
2636  *	a legitimate response by Jon Postel in a telephone conversation
2637  *	with Rick Adams on 25 Jan 89.
2638  */
2639 void
2640 passive(void)
2641 {
2642 	int len, on;
2643 	char *p, *a;
2644 
2645 	if (pdata >= 0)		/* close old port if one set */
2646 		close(pdata);
2647 
2648 	pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
2649 	if (pdata < 0) {
2650 		perror_reply(425, "Can't open passive connection");
2651 		return;
2652 	}
2653 	on = 1;
2654 	if (setsockopt(pdata, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
2655 		syslog(LOG_WARNING, "pdata setsockopt (SO_REUSEADDR): %m");
2656 
2657 	(void) seteuid((uid_t)0);
2658 
2659 #ifdef IP_PORTRANGE
2660 	if (ctrl_addr.su_family == AF_INET) {
2661 	    on = restricted_data_ports ? IP_PORTRANGE_HIGH
2662 				       : IP_PORTRANGE_DEFAULT;
2663 
2664 	    if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE,
2665 			    &on, sizeof(on)) < 0)
2666 		    goto pasv_error;
2667 	}
2668 #endif
2669 #ifdef IPV6_PORTRANGE
2670 	if (ctrl_addr.su_family == AF_INET6) {
2671 	    on = restricted_data_ports ? IPV6_PORTRANGE_HIGH
2672 				       : IPV6_PORTRANGE_DEFAULT;
2673 
2674 	    if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE,
2675 			    &on, sizeof(on)) < 0)
2676 		    goto pasv_error;
2677 	}
2678 #endif
2679 
2680 	pasv_addr = ctrl_addr;
2681 	pasv_addr.su_port = 0;
2682 	if (bind(pdata, (struct sockaddr *)&pasv_addr, pasv_addr.su_len) < 0)
2683 		goto pasv_error;
2684 
2685 	(void) seteuid((uid_t)pw->pw_uid);
2686 
2687 	len = sizeof(pasv_addr);
2688 	if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0)
2689 		goto pasv_error;
2690 	if (listen(pdata, 1) < 0)
2691 		goto pasv_error;
2692 	if (pasv_addr.su_family == AF_INET)
2693 		a = (char *) &pasv_addr.su_sin.sin_addr;
2694 	else if (pasv_addr.su_family == AF_INET6 &&
2695 		 IN6_IS_ADDR_V4MAPPED(&pasv_addr.su_sin6.sin6_addr))
2696 		a = (char *) &pasv_addr.su_sin6.sin6_addr.s6_addr[12];
2697 	else
2698 		goto pasv_error;
2699 
2700 	p = (char *) &pasv_addr.su_port;
2701 
2702 #define UC(b) (((int) b) & 0xff)
2703 
2704 	reply(227, "Entering Passive Mode (%d,%d,%d,%d,%d,%d)", UC(a[0]),
2705 		UC(a[1]), UC(a[2]), UC(a[3]), UC(p[0]), UC(p[1]));
2706 	return;
2707 
2708 pasv_error:
2709 	(void) seteuid((uid_t)pw->pw_uid);
2710 	(void) close(pdata);
2711 	pdata = -1;
2712 	perror_reply(425, "Can't open passive connection");
2713 	return;
2714 }
2715 
2716 /*
2717  * Long Passive defined in RFC 1639.
2718  *     228 Entering Long Passive Mode
2719  *         (af, hal, h1, h2, h3,..., pal, p1, p2...)
2720  */
2721 
2722 void
2723 long_passive(char *cmd, int pf)
2724 {
2725 	int len, on;
2726 	char *p, *a;
2727 
2728 	if (pdata >= 0)		/* close old port if one set */
2729 		close(pdata);
2730 
2731 	if (pf != PF_UNSPEC) {
2732 		if (ctrl_addr.su_family != pf) {
2733 			switch (ctrl_addr.su_family) {
2734 			case AF_INET:
2735 				pf = 1;
2736 				break;
2737 			case AF_INET6:
2738 				pf = 2;
2739 				break;
2740 			default:
2741 				pf = 0;
2742 				break;
2743 			}
2744 			/*
2745 			 * XXX
2746 			 * only EPRT/EPSV ready clients will understand this
2747 			 */
2748 			if (strcmp(cmd, "EPSV") == 0 && pf) {
2749 				reply(522, "Network protocol mismatch, "
2750 					"use (%d)", pf);
2751 			} else
2752 				reply(501, "Network protocol mismatch"); /*XXX*/
2753 
2754 			return;
2755 		}
2756 	}
2757 
2758 	pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
2759 	if (pdata < 0) {
2760 		perror_reply(425, "Can't open passive connection");
2761 		return;
2762 	}
2763 	on = 1;
2764 	if (setsockopt(pdata, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
2765 		syslog(LOG_WARNING, "pdata setsockopt (SO_REUSEADDR): %m");
2766 
2767 	(void) seteuid((uid_t)0);
2768 
2769 	pasv_addr = ctrl_addr;
2770 	pasv_addr.su_port = 0;
2771 	len = pasv_addr.su_len;
2772 
2773 #ifdef IP_PORTRANGE
2774 	if (ctrl_addr.su_family == AF_INET) {
2775 	    on = restricted_data_ports ? IP_PORTRANGE_HIGH
2776 				       : IP_PORTRANGE_DEFAULT;
2777 
2778 	    if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE,
2779 			    &on, sizeof(on)) < 0)
2780 		    goto pasv_error;
2781 	}
2782 #endif
2783 #ifdef IPV6_PORTRANGE
2784 	if (ctrl_addr.su_family == AF_INET6) {
2785 	    on = restricted_data_ports ? IPV6_PORTRANGE_HIGH
2786 				       : IPV6_PORTRANGE_DEFAULT;
2787 
2788 	    if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE,
2789 			    &on, sizeof(on)) < 0)
2790 		    goto pasv_error;
2791 	}
2792 #endif
2793 
2794 	if (bind(pdata, (struct sockaddr *)&pasv_addr, len) < 0)
2795 		goto pasv_error;
2796 
2797 	(void) seteuid((uid_t)pw->pw_uid);
2798 
2799 	if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0)
2800 		goto pasv_error;
2801 	if (listen(pdata, 1) < 0)
2802 		goto pasv_error;
2803 
2804 #define UC(b) (((int) b) & 0xff)
2805 
2806 	if (strcmp(cmd, "LPSV") == 0) {
2807 		p = (char *)&pasv_addr.su_port;
2808 		switch (pasv_addr.su_family) {
2809 		case AF_INET:
2810 			a = (char *) &pasv_addr.su_sin.sin_addr;
2811 		v4_reply:
2812 			reply(228,
2813 "Entering Long Passive Mode (%d,%d,%d,%d,%d,%d,%d,%d,%d)",
2814 			      4, 4, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
2815 			      2, UC(p[0]), UC(p[1]));
2816 			return;
2817 		case AF_INET6:
2818 			if (IN6_IS_ADDR_V4MAPPED(&pasv_addr.su_sin6.sin6_addr)) {
2819 				a = (char *) &pasv_addr.su_sin6.sin6_addr.s6_addr[12];
2820 				goto v4_reply;
2821 			}
2822 			a = (char *) &pasv_addr.su_sin6.sin6_addr;
2823 			reply(228,
2824 "Entering Long Passive Mode "
2825 "(%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d)",
2826 			      6, 16, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
2827 			      UC(a[4]), UC(a[5]), UC(a[6]), UC(a[7]),
2828 			      UC(a[8]), UC(a[9]), UC(a[10]), UC(a[11]),
2829 			      UC(a[12]), UC(a[13]), UC(a[14]), UC(a[15]),
2830 			      2, UC(p[0]), UC(p[1]));
2831 			return;
2832 		}
2833 	} else if (strcmp(cmd, "EPSV") == 0) {
2834 		switch (pasv_addr.su_family) {
2835 		case AF_INET:
2836 		case AF_INET6:
2837 			reply(229, "Entering Extended Passive Mode (|||%d|)",
2838 				ntohs(pasv_addr.su_port));
2839 			return;
2840 		}
2841 	} else {
2842 		/* more proper error code? */
2843 	}
2844 
2845 pasv_error:
2846 	(void) seteuid((uid_t)pw->pw_uid);
2847 	(void) close(pdata);
2848 	pdata = -1;
2849 	perror_reply(425, "Can't open passive connection");
2850 	return;
2851 }
2852 
2853 /*
2854  * Generate unique name for file with basename "local"
2855  * and open the file in order to avoid possible races.
2856  * Try "local" first, then "local.1", "local.2" etc, up to "local.99".
2857  * Return descriptor to the file, set "name" to its name.
2858  *
2859  * Generates failure reply on error.
2860  */
2861 static int
2862 guniquefd(char *local, char **name)
2863 {
2864 	static char new[MAXPATHLEN];
2865 	struct stat st;
2866 	char *cp;
2867 	int count;
2868 	int fd;
2869 
2870 	cp = strrchr(local, '/');
2871 	if (cp)
2872 		*cp = '\0';
2873 	if (stat(cp ? local : ".", &st) < 0) {
2874 		perror_reply(553, cp ? local : ".");
2875 		return (-1);
2876 	}
2877 	if (cp) {
2878 		/*
2879 		 * Let not overwrite dirname with counter suffix.
2880 		 * -4 is for /nn\0
2881 		 * In this extreme case dot won't be put in front of suffix.
2882 		 */
2883 		if (strlen(local) > sizeof(new) - 4) {
2884 			reply(553, "Pathname too long");
2885 			return (-1);
2886 		}
2887 		*cp = '/';
2888 	}
2889 	/* -4 is for the .nn<null> we put on the end below */
2890 	(void) snprintf(new, sizeof(new) - 4, "%s", local);
2891 	cp = new + strlen(new);
2892 	/*
2893 	 * Don't generate dotfile unless requested explicitly.
2894 	 * This covers the case when basename gets truncated off
2895 	 * by buffer size.
2896 	 */
2897 	if (cp > new && cp[-1] != '/')
2898 		*cp++ = '.';
2899 	for (count = 0; count < 100; count++) {
2900 		/* At count 0 try unmodified name */
2901 		if (count)
2902 			(void)sprintf(cp, "%d", count);
2903 		if ((fd = open(count ? new : local,
2904 		    O_RDWR | O_CREAT | O_EXCL, 0666)) >= 0) {
2905 			*name = count ? new : local;
2906 			return (fd);
2907 		}
2908 		if (errno != EEXIST) {
2909 			perror_reply(553, count ? new : local);
2910 			return (-1);
2911 		}
2912 	}
2913 	reply(452, "Unique file name cannot be created.");
2914 	return (-1);
2915 }
2916 
2917 /*
2918  * Format and send reply containing system error number.
2919  */
2920 void
2921 perror_reply(int code, char *string)
2922 {
2923 
2924 	reply(code, "%s: %s.", string, strerror(errno));
2925 }
2926 
2927 static char *onefile[] = {
2928 	"",
2929 	0
2930 };
2931 
2932 void
2933 send_file_list(char *whichf)
2934 {
2935 	struct stat st;
2936 	DIR *dirp = NULL;
2937 	struct dirent *dir;
2938 	FILE *dout = NULL;
2939 	char **dirlist, *dirname;
2940 	int simple = 0;
2941 	int freeglob = 0;
2942 	glob_t gl;
2943 
2944 	if (strpbrk(whichf, "~{[*?") != NULL) {
2945 		int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE;
2946 
2947 		memset(&gl, 0, sizeof(gl));
2948 		gl.gl_matchc = MAXGLOBARGS;
2949 		flags |= GLOB_LIMIT;
2950 		freeglob = 1;
2951 		if (glob(whichf, flags, 0, &gl)) {
2952 			reply(550, "not found");
2953 			goto out;
2954 		} else if (gl.gl_pathc == 0) {
2955 			errno = ENOENT;
2956 			perror_reply(550, whichf);
2957 			goto out;
2958 		}
2959 		dirlist = gl.gl_pathv;
2960 	} else {
2961 		onefile[0] = whichf;
2962 		dirlist = onefile;
2963 		simple = 1;
2964 	}
2965 
2966 	while ((dirname = *dirlist++)) {
2967 		if (stat(dirname, &st) < 0) {
2968 			/*
2969 			 * If user typed "ls -l", etc, and the client
2970 			 * used NLST, do what the user meant.
2971 			 */
2972 			if (dirname[0] == '-' && *dirlist == NULL &&
2973 			    transflag == 0) {
2974 				retrieve(_PATH_LS " %s", dirname);
2975 				goto out;
2976 			}
2977 			perror_reply(550, whichf);
2978 			if (dout != NULL) {
2979 				(void) fclose(dout);
2980 				transflag = 0;
2981 				data = -1;
2982 				pdata = -1;
2983 			}
2984 			goto out;
2985 		}
2986 
2987 		if (S_ISREG(st.st_mode)) {
2988 			if (dout == NULL) {
2989 				dout = dataconn("file list", (off_t)-1, "w");
2990 				if (dout == NULL)
2991 					goto out;
2992 				transflag++;
2993 			}
2994 			fprintf(dout, "%s%s\n", dirname,
2995 				type == TYPE_A ? "\r" : "");
2996 			byte_count += strlen(dirname) + 1;
2997 			continue;
2998 		} else if (!S_ISDIR(st.st_mode))
2999 			continue;
3000 
3001 		if ((dirp = opendir(dirname)) == NULL)
3002 			continue;
3003 
3004 		while ((dir = readdir(dirp)) != NULL) {
3005 			char nbuf[MAXPATHLEN];
3006 
3007 			if (recvurg) {
3008 				myoob();
3009 				recvurg = 0;
3010 				transflag = 0;
3011 				goto out;
3012 			}
3013 
3014 			if (dir->d_name[0] == '.' && dir->d_namlen == 1)
3015 				continue;
3016 			if (dir->d_name[0] == '.' && dir->d_name[1] == '.' &&
3017 			    dir->d_namlen == 2)
3018 				continue;
3019 
3020 			snprintf(nbuf, sizeof(nbuf),
3021 				"%s/%s", dirname, dir->d_name);
3022 
3023 			/*
3024 			 * We have to do a stat to insure it's
3025 			 * not a directory or special file.
3026 			 */
3027 			if (simple || (stat(nbuf, &st) == 0 &&
3028 			    S_ISREG(st.st_mode))) {
3029 				if (dout == NULL) {
3030 					dout = dataconn("file list", (off_t)-1,
3031 						"w");
3032 					if (dout == NULL)
3033 						goto out;
3034 					transflag++;
3035 				}
3036 				if (nbuf[0] == '.' && nbuf[1] == '/')
3037 					fprintf(dout, "%s%s\n", &nbuf[2],
3038 						type == TYPE_A ? "\r" : "");
3039 				else
3040 					fprintf(dout, "%s%s\n", nbuf,
3041 						type == TYPE_A ? "\r" : "");
3042 				byte_count += strlen(nbuf) + 1;
3043 			}
3044 		}
3045 		(void) closedir(dirp);
3046 	}
3047 
3048 	if (dout == NULL)
3049 		reply(550, "No files found.");
3050 	else if (ferror(dout) != 0)
3051 		perror_reply(550, "Data connection");
3052 	else
3053 		reply(226, "Transfer complete.");
3054 
3055 	transflag = 0;
3056 	if (dout != NULL)
3057 		(void) fclose(dout);
3058 	data = -1;
3059 	pdata = -1;
3060 out:
3061 	if (freeglob) {
3062 		freeglob = 0;
3063 		globfree(&gl);
3064 	}
3065 }
3066 
3067 void
3068 reapchild(int signo)
3069 {
3070 	while (wait3(NULL, WNOHANG, NULL) > 0);
3071 }
3072 
3073 #ifdef OLD_SETPROCTITLE
3074 /*
3075  * Clobber argv so ps will show what we're doing.  (Stolen from sendmail.)
3076  * Warning, since this is usually started from inetd.conf, it often doesn't
3077  * have much of an environment or arglist to overwrite.
3078  */
3079 void
3080 setproctitle(const char *fmt, ...)
3081 {
3082 	int i;
3083 	va_list ap;
3084 	char *p, *bp, ch;
3085 	char buf[LINE_MAX];
3086 
3087 	va_start(ap, fmt);
3088 	(void)vsnprintf(buf, sizeof(buf), fmt, ap);
3089 
3090 	/* make ps print our process name */
3091 	p = Argv[0];
3092 	*p++ = '-';
3093 
3094 	i = strlen(buf);
3095 	if (i > LastArgv - p - 2) {
3096 		i = LastArgv - p - 2;
3097 		buf[i] = '\0';
3098 	}
3099 	bp = buf;
3100 	while (ch = *bp++)
3101 		if (ch != '\n' && ch != '\r')
3102 			*p++ = ch;
3103 	while (p < LastArgv)
3104 		*p++ = ' ';
3105 }
3106 #endif /* OLD_SETPROCTITLE */
3107 
3108 static void
3109 logxfer(char *name, off_t size, time_t start)
3110 {
3111 	char buf[1024];
3112 	char path[MAXPATHLEN + 1];
3113 	time_t now;
3114 
3115 	if (statfd >= 0 && getwd(path) != NULL) {
3116 		time(&now);
3117 		snprintf(buf, sizeof(buf), "%.20s!%s!%s!%s/%s!%qd!%ld\n",
3118 			ctime(&now)+4, ident, remotehost,
3119 			path, name, (long long)size,
3120 			(long)(now - start + (now == start)));
3121 		write(statfd, buf, strlen(buf));
3122 	}
3123 }
3124 
3125 static char *
3126 doublequote(char *s)
3127 {
3128 	int n;
3129 	char *p, *s2;
3130 
3131 	for (p = s, n = 0; *p; p++)
3132 		if (*p == '"')
3133 			n++;
3134 
3135 	if ((s2 = malloc(p - s + n + 1)) == NULL)
3136 		return (NULL);
3137 
3138 	for (p = s2; *s; s++, p++) {
3139 		if ((*p = *s) == '"')
3140 			*(++p) = '"';
3141 	}
3142 	*p = '\0';
3143 
3144 	return (s2);
3145 }
3146 
3147 /* setup server socket for specified address family */
3148 /* if af is PF_UNSPEC more than one socket may be returned */
3149 /* the returned list is dynamically allocated, so caller needs to free it */
3150 static int *
3151 socksetup(int af, char *bindname, const char *bindport)
3152 {
3153 	struct addrinfo hints, *res, *r;
3154 	int error, maxs, *s, *socks;
3155 	const int on = 1;
3156 
3157 	memset(&hints, 0, sizeof(hints));
3158 	hints.ai_flags = AI_PASSIVE;
3159 	hints.ai_family = af;
3160 	hints.ai_socktype = SOCK_STREAM;
3161 	error = getaddrinfo(bindname, bindport, &hints, &res);
3162 	if (error) {
3163 		syslog(LOG_ERR, "%s", gai_strerror(error));
3164 		if (error == EAI_SYSTEM)
3165 			syslog(LOG_ERR, "%s", strerror(errno));
3166 		return NULL;
3167 	}
3168 
3169 	/* Count max number of sockets we may open */
3170 	for (maxs = 0, r = res; r; r = r->ai_next, maxs++)
3171 		;
3172 	socks = malloc((maxs + 1) * sizeof(int));
3173 	if (!socks) {
3174 		freeaddrinfo(res);
3175 		syslog(LOG_ERR, "couldn't allocate memory for sockets");
3176 		return NULL;
3177 	}
3178 
3179 	*socks = 0;   /* num of sockets counter at start of array */
3180 	s = socks + 1;
3181 	for (r = res; r; r = r->ai_next) {
3182 		*s = socket(r->ai_family, r->ai_socktype, r->ai_protocol);
3183 		if (*s < 0) {
3184 			syslog(LOG_DEBUG, "control socket: %m");
3185 			continue;
3186 		}
3187 		if (setsockopt(*s, SOL_SOCKET, SO_REUSEADDR,
3188 		    &on, sizeof(on)) < 0)
3189 			syslog(LOG_WARNING,
3190 			    "control setsockopt (SO_REUSEADDR): %m");
3191 		if (r->ai_family == AF_INET6) {
3192 			if (setsockopt(*s, IPPROTO_IPV6, IPV6_V6ONLY,
3193 			    &on, sizeof(on)) < 0)
3194 				syslog(LOG_WARNING,
3195 				    "control setsockopt (IPV6_V6ONLY): %m");
3196 		}
3197 		if (bind(*s, r->ai_addr, r->ai_addrlen) < 0) {
3198 			syslog(LOG_DEBUG, "control bind: %m");
3199 			close(*s);
3200 			continue;
3201 		}
3202 		(*socks)++;
3203 		s++;
3204 	}
3205 
3206 	if (res)
3207 		freeaddrinfo(res);
3208 
3209 	if (*socks == 0) {
3210 		syslog(LOG_ERR, "control socket: Couldn't bind to any socket");
3211 		free(socks);
3212 		return NULL;
3213 	}
3214 	return(socks);
3215 }
3216