xref: /freebsd/libexec/ftpd/ftpd.c (revision 5bb3134a8c21cb87b30e135ef168483f0333dabb)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #if 0
33 #ifndef lint
34 static char copyright[] =
35 "@(#) Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994\n\
36 	The Regents of the University of California.  All rights reserved.\n";
37 #endif /* not lint */
38 #endif
39 
40 #ifndef lint
41 #if 0
42 static char sccsid[] = "@(#)ftpd.c	8.4 (Berkeley) 4/16/94";
43 #endif
44 #endif /* not lint */
45 
46 #include <sys/cdefs.h>
47 __FBSDID("$FreeBSD$");
48 
49 /*
50  * FTP server.
51  */
52 #include <sys/param.h>
53 #include <sys/ioctl.h>
54 #include <sys/mman.h>
55 #include <sys/socket.h>
56 #include <sys/stat.h>
57 #include <sys/time.h>
58 #include <sys/wait.h>
59 
60 #include <netinet/in.h>
61 #include <netinet/in_systm.h>
62 #include <netinet/ip.h>
63 #include <netinet/tcp.h>
64 
65 #define	FTP_NAMES
66 #include <arpa/ftp.h>
67 #include <arpa/inet.h>
68 #include <arpa/telnet.h>
69 
70 #include <ctype.h>
71 #include <dirent.h>
72 #include <err.h>
73 #include <errno.h>
74 #include <fcntl.h>
75 #include <glob.h>
76 #include <limits.h>
77 #include <netdb.h>
78 #include <pwd.h>
79 #include <grp.h>
80 #include <opie.h>
81 #include <signal.h>
82 #include <stdint.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 "blacklist_client.h"
99 #include "pathnames.h"
100 #include "extern.h"
101 
102 #include <stdarg.h>
103 
104 static char version[] = "Version 6.00LS";
105 #undef main
106 
107 union sockunion ctrl_addr;
108 union sockunion data_source;
109 union sockunion data_dest;
110 union sockunion his_addr;
111 union sockunion pasv_addr;
112 
113 int	daemon_mode;
114 int	data;
115 int	dataport;
116 int	hostinfo = 1;	/* print host-specific info in messages */
117 int	logged_in;
118 struct	passwd *pw;
119 char	*homedir;
120 int	ftpdebug;
121 int	timeout = 900;    /* timeout after 15 minutes of inactivity */
122 int	maxtimeout = 7200;/* don't allow idle time to be set beyond 2 hours */
123 int	logging;
124 int	restricted_data_ports = 1;
125 int	paranoid = 1;	  /* be extra careful about security */
126 int	anon_only = 0;    /* Only anonymous ftp allowed */
127 int	assumeutf8 = 0;   /* Assume that server file names are in UTF-8 */
128 int	guest;
129 int	dochroot;
130 char	*chrootdir;
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 int	use_blacklist = 0;
147 
148 off_t	file_size;
149 off_t	byte_count;
150 #if !defined(CMASK) || CMASK == 0
151 #undef CMASK
152 #define CMASK 027
153 #endif
154 int	defumask = CMASK;		/* default umask value */
155 char	tmpline[7];
156 char	*hostname;
157 int	epsvall = 0;
158 
159 #ifdef VIRTUAL_HOSTING
160 char	*ftpuser;
161 
162 static struct ftphost {
163 	struct ftphost	*next;
164 	struct addrinfo *hostinfo;
165 	char		*hostname;
166 	char		*anonuser;
167 	char		*statfile;
168 	char		*welcome;
169 	char		*loginmsg;
170 } *thishost, *firsthost;
171 
172 #endif
173 char	remotehost[NI_MAXHOST];
174 char	*ident = NULL;
175 
176 static char	wtmpid[20];
177 
178 #ifdef USE_PAM
179 static int	auth_pam(struct passwd**, const char*);
180 pam_handle_t	*pamh = NULL;
181 #endif
182 
183 static struct opie	opiedata;
184 static char		opieprompt[OPIE_CHALLENGE_MAX+1];
185 static int		pwok;
186 
187 char	*pid_file = NULL; /* means default location to pidfile(3) */
188 
189 /*
190  * Limit number of pathnames that glob can return.
191  * A limit of 0 indicates the number of pathnames is unlimited.
192  */
193 #define MAXGLOBARGS	16384
194 #
195 
196 /*
197  * Timeout intervals for retrying connections
198  * to hosts that don't accept PORT cmds.  This
199  * is a kludge, but given the problems with TCP...
200  */
201 #define	SWAITMAX	90	/* wait at most 90 seconds */
202 #define	SWAITINT	5	/* interval between retries */
203 
204 int	swaitmax = SWAITMAX;
205 int	swaitint = SWAITINT;
206 
207 #ifdef SETPROCTITLE
208 char	proctitle[LINE_MAX];	/* initial part of title */
209 #endif /* SETPROCTITLE */
210 
211 #define LOGCMD(cmd, file)		logcmd((cmd), (file), NULL, -1)
212 #define LOGCMD2(cmd, file1, file2)	logcmd((cmd), (file1), (file2), -1)
213 #define LOGBYTES(cmd, file, cnt)	logcmd((cmd), (file), NULL, (cnt))
214 
215 static	volatile sig_atomic_t recvurg;
216 static	int transflag;		/* NB: for debugging only */
217 
218 #define STARTXFER	flagxfer(1)
219 #define ENDXFER		flagxfer(0)
220 
221 #define START_UNSAFE	maskurg(1)
222 #define END_UNSAFE	maskurg(0)
223 
224 /* It's OK to put an `else' clause after this macro. */
225 #define CHECKOOB(action)						\
226 	if (recvurg) {							\
227 		recvurg = 0;						\
228 		if (myoob()) {						\
229 			ENDXFER;					\
230 			action;						\
231 		}							\
232 	}
233 
234 #ifdef VIRTUAL_HOSTING
235 static void	 inithosts(int);
236 static void	 selecthost(union sockunion *);
237 #endif
238 static void	 ack(char *);
239 static void	 sigurg(int);
240 static void	 maskurg(int);
241 static void	 flagxfer(int);
242 static int	 myoob(void);
243 static int	 checkuser(char *, char *, int, char **, int *);
244 static FILE	*dataconn(char *, off_t, char *);
245 static void	 dolog(struct sockaddr *);
246 static void	 end_login(void);
247 static FILE	*getdatasock(char *);
248 static int	 guniquefd(char *, char **);
249 static void	 lostconn(int);
250 static void	 sigquit(int);
251 static int	 receive_data(FILE *, FILE *);
252 static int	 send_data(FILE *, FILE *, size_t, off_t, int);
253 static struct passwd *
254 		 sgetpwnam(char *);
255 static char	*sgetsave(char *);
256 static void	 reapchild(int);
257 static void	 appendf(char **, char *, ...) __printflike(2, 3);
258 static void	 logcmd(char *, char *, char *, off_t);
259 static void      logxfer(char *, off_t, time_t);
260 static char	*doublequote(char *);
261 static int	*socksetup(int, char *, const char *);
262 
263 int
264 main(int argc, char *argv[], char **envp)
265 {
266 	socklen_t addrlen;
267 	int ch, on = 1, tos, s = STDIN_FILENO;
268 	char *cp, line[LINE_MAX];
269 	FILE *fd;
270 	char	*bindname = NULL;
271 	const char *bindport = "ftp";
272 	int	family = AF_UNSPEC;
273 	struct sigaction sa;
274 
275 	tzset();		/* in case no timezone database in ~ftp */
276 	sigemptyset(&sa.sa_mask);
277 	sa.sa_flags = SA_RESTART;
278 
279 	/*
280 	 * Prevent diagnostic messages from appearing on stderr.
281 	 * We run as a daemon or from inetd; in both cases, there's
282 	 * more reason in logging to syslog.
283 	 */
284 	(void) freopen(_PATH_DEVNULL, "w", stderr);
285 	opterr = 0;
286 
287 	/*
288 	 * LOG_NDELAY sets up the logging connection immediately,
289 	 * necessary for anonymous ftp's that chroot and can't do it later.
290 	 */
291 	openlog("ftpd", LOG_PID | LOG_NDELAY, LOG_FTP);
292 
293 	while ((ch = getopt(argc, argv,
294 	                    "468a:ABdDEhlmMoOp:P:rRSt:T:u:UvW")) != -1) {
295 		switch (ch) {
296 		case '4':
297 			family = (family == AF_INET6) ? AF_UNSPEC : AF_INET;
298 			break;
299 
300 		case '6':
301 			family = (family == AF_INET) ? AF_UNSPEC : AF_INET6;
302 			break;
303 
304 		case '8':
305 			assumeutf8 = 1;
306 			break;
307 
308 		case 'a':
309 			bindname = optarg;
310 			break;
311 
312 		case 'A':
313 			anon_only = 1;
314 			break;
315 
316 		case 'B':
317 #ifdef USE_BLACKLIST
318 			use_blacklist = 1;
319 #else
320 			syslog(LOG_WARNING, "not compiled with USE_BLACKLIST support");
321 #endif
322 			break;
323 
324 		case 'd':
325 			ftpdebug++;
326 			break;
327 
328 		case 'D':
329 			daemon_mode++;
330 			break;
331 
332 		case 'E':
333 			noepsv = 1;
334 			break;
335 
336 		case 'h':
337 			hostinfo = 0;
338 			break;
339 
340 		case 'l':
341 			logging++;	/* > 1 == extra logging */
342 			break;
343 
344 		case 'm':
345 			noguestmod = 0;
346 			break;
347 
348 		case 'M':
349 			noguestmkd = 1;
350 			break;
351 
352 		case 'o':
353 			noretr = 1;
354 			break;
355 
356 		case 'O':
357 			noguestretr = 1;
358 			break;
359 
360 		case 'p':
361 			pid_file = optarg;
362 			break;
363 
364 		case 'P':
365 			bindport = optarg;
366 			break;
367 
368 		case 'r':
369 			readonly = 1;
370 			break;
371 
372 		case 'R':
373 			paranoid = 0;
374 			break;
375 
376 		case 'S':
377 			stats++;
378 			break;
379 
380 		case 't':
381 			timeout = atoi(optarg);
382 			if (maxtimeout < timeout)
383 				maxtimeout = timeout;
384 			break;
385 
386 		case 'T':
387 			maxtimeout = atoi(optarg);
388 			if (timeout > maxtimeout)
389 				timeout = maxtimeout;
390 			break;
391 
392 		case 'u':
393 		    {
394 			long val = 0;
395 
396 			val = strtol(optarg, &optarg, 8);
397 			if (*optarg != '\0' || val < 0)
398 				syslog(LOG_WARNING, "bad value for -u");
399 			else
400 				defumask = val;
401 			break;
402 		    }
403 		case 'U':
404 			restricted_data_ports = 0;
405 			break;
406 
407 		case 'v':
408 			ftpdebug++;
409 			break;
410 
411 		case 'W':
412 			dowtmp = 0;
413 			break;
414 
415 		default:
416 			syslog(LOG_WARNING, "unknown flag -%c ignored", optopt);
417 			break;
418 		}
419 	}
420 
421 	/* handle filesize limit gracefully */
422 	sa.sa_handler = SIG_IGN;
423 	(void)sigaction(SIGXFSZ, &sa, NULL);
424 
425 	if (daemon_mode) {
426 		int *ctl_sock, fd, maxfd = -1, nfds, i;
427 		fd_set defreadfds, readfds;
428 		pid_t pid;
429 		struct pidfh *pfh;
430 
431 		if ((pfh = pidfile_open(pid_file, 0600, &pid)) == NULL) {
432 			if (errno == EEXIST) {
433 				syslog(LOG_ERR, "%s already running, pid %d",
434 				       getprogname(), (int)pid);
435 				exit(1);
436 			}
437 			syslog(LOG_WARNING, "pidfile_open: %m");
438 		}
439 
440 		/*
441 		 * Detach from parent.
442 		 */
443 		if (daemon(1, 1) < 0) {
444 			syslog(LOG_ERR, "failed to become a daemon");
445 			exit(1);
446 		}
447 
448 		if (pfh != NULL && pidfile_write(pfh) == -1)
449 			syslog(LOG_WARNING, "pidfile_write: %m");
450 
451 		sa.sa_handler = reapchild;
452 		(void)sigaction(SIGCHLD, &sa, NULL);
453 
454 #ifdef VIRTUAL_HOSTING
455 		inithosts(family);
456 #endif
457 
458 		/*
459 		 * Open a socket, bind it to the FTP port, and start
460 		 * listening.
461 		 */
462 		ctl_sock = socksetup(family, bindname, bindport);
463 		if (ctl_sock == NULL)
464 			exit(1);
465 
466 		FD_ZERO(&defreadfds);
467 		for (i = 1; i <= *ctl_sock; i++) {
468 			FD_SET(ctl_sock[i], &defreadfds);
469 			if (listen(ctl_sock[i], 32) < 0) {
470 				syslog(LOG_ERR, "control listen: %m");
471 				exit(1);
472 			}
473 			if (maxfd < ctl_sock[i])
474 				maxfd = ctl_sock[i];
475 		}
476 
477 		/*
478 		 * Loop forever accepting connection requests and forking off
479 		 * children to handle them.
480 		 */
481 		while (1) {
482 			FD_COPY(&defreadfds, &readfds);
483 			nfds = select(maxfd + 1, &readfds, NULL, NULL, 0);
484 			if (nfds <= 0) {
485 				if (nfds < 0 && errno != EINTR)
486 					syslog(LOG_WARNING, "select: %m");
487 				continue;
488 			}
489 
490 			pid = -1;
491                         for (i = 1; i <= *ctl_sock; i++)
492 				if (FD_ISSET(ctl_sock[i], &readfds)) {
493 					addrlen = sizeof(his_addr);
494 					fd = accept(ctl_sock[i],
495 					    (struct sockaddr *)&his_addr,
496 					    &addrlen);
497 					if (fd == -1) {
498 						syslog(LOG_WARNING,
499 						       "accept: %m");
500 						continue;
501 					}
502 					switch (pid = fork()) {
503 					case 0:
504 						/* child */
505 						(void) dup2(fd, s);
506 						(void) dup2(fd, STDOUT_FILENO);
507 						(void) close(fd);
508 						for (i = 1; i <= *ctl_sock; i++)
509 							close(ctl_sock[i]);
510 						if (pfh != NULL)
511 							pidfile_close(pfh);
512 						goto gotchild;
513 					case -1:
514 						syslog(LOG_WARNING, "fork: %m");
515 						/* FALLTHROUGH */
516 					default:
517 						close(fd);
518 					}
519 				}
520 		}
521 	} else {
522 		addrlen = sizeof(his_addr);
523 		if (getpeername(s, (struct sockaddr *)&his_addr, &addrlen) < 0) {
524 			syslog(LOG_ERR, "getpeername (%s): %m",argv[0]);
525 			exit(1);
526 		}
527 
528 #ifdef VIRTUAL_HOSTING
529 		if (his_addr.su_family == AF_INET6 &&
530 		    IN6_IS_ADDR_V4MAPPED(&his_addr.su_sin6.sin6_addr))
531 			family = AF_INET;
532 		else
533 			family = his_addr.su_family;
534 		inithosts(family);
535 #endif
536 	}
537 
538 gotchild:
539 	sa.sa_handler = SIG_DFL;
540 	(void)sigaction(SIGCHLD, &sa, NULL);
541 
542 	sa.sa_handler = sigurg;
543 	sa.sa_flags = 0;		/* don't restart syscalls for SIGURG */
544 	(void)sigaction(SIGURG, &sa, NULL);
545 
546 	sigfillset(&sa.sa_mask);	/* block all signals in handler */
547 	sa.sa_flags = SA_RESTART;
548 	sa.sa_handler = sigquit;
549 	(void)sigaction(SIGHUP, &sa, NULL);
550 	(void)sigaction(SIGINT, &sa, NULL);
551 	(void)sigaction(SIGQUIT, &sa, NULL);
552 	(void)sigaction(SIGTERM, &sa, NULL);
553 
554 	sa.sa_handler = lostconn;
555 	(void)sigaction(SIGPIPE, &sa, NULL);
556 
557 	addrlen = sizeof(ctrl_addr);
558 	if (getsockname(s, (struct sockaddr *)&ctrl_addr, &addrlen) < 0) {
559 		syslog(LOG_ERR, "getsockname (%s): %m",argv[0]);
560 		exit(1);
561 	}
562 	dataport = ntohs(ctrl_addr.su_port) - 1; /* as per RFC 959 */
563 #ifdef VIRTUAL_HOSTING
564 	/* select our identity from virtual host table */
565 	selecthost(&ctrl_addr);
566 #endif
567 #ifdef IP_TOS
568 	if (ctrl_addr.su_family == AF_INET)
569       {
570 	tos = IPTOS_LOWDELAY;
571 	if (setsockopt(s, IPPROTO_IP, IP_TOS, &tos, sizeof(int)) < 0)
572 		syslog(LOG_WARNING, "control setsockopt (IP_TOS): %m");
573       }
574 #endif
575 	/*
576 	 * Disable Nagle on the control channel so that we don't have to wait
577 	 * for peer's ACK before issuing our next reply.
578 	 */
579 	if (setsockopt(s, IPPROTO_TCP, TCP_NODELAY, &on, sizeof(on)) < 0)
580 		syslog(LOG_WARNING, "control setsockopt (TCP_NODELAY): %m");
581 
582 	data_source.su_port = htons(ntohs(ctrl_addr.su_port) - 1);
583 
584 	(void)snprintf(wtmpid, sizeof(wtmpid), "%xftpd", getpid());
585 
586 	/* Try to handle urgent data inline */
587 #ifdef SO_OOBINLINE
588 	if (setsockopt(s, SOL_SOCKET, SO_OOBINLINE, &on, sizeof(on)) < 0)
589 		syslog(LOG_WARNING, "control setsockopt (SO_OOBINLINE): %m");
590 #endif
591 
592 #ifdef	F_SETOWN
593 	if (fcntl(s, F_SETOWN, getpid()) == -1)
594 		syslog(LOG_ERR, "fcntl F_SETOWN: %m");
595 #endif
596 	dolog((struct sockaddr *)&his_addr);
597 	/*
598 	 * Set up default state
599 	 */
600 	data = -1;
601 	type = TYPE_A;
602 	form = FORM_N;
603 	stru = STRU_F;
604 	mode = MODE_S;
605 	tmpline[0] = '\0';
606 
607 	/* If logins are disabled, print out the message. */
608 	if ((fd = fopen(_PATH_NOLOGIN,"r")) != NULL) {
609 		while (fgets(line, sizeof(line), fd) != NULL) {
610 			if ((cp = strchr(line, '\n')) != NULL)
611 				*cp = '\0';
612 			lreply(530, "%s", line);
613 		}
614 		(void) fflush(stdout);
615 		(void) fclose(fd);
616 		reply(530, "System not available.");
617 		exit(0);
618 	}
619 #ifdef VIRTUAL_HOSTING
620 	fd = fopen(thishost->welcome, "r");
621 #else
622 	fd = fopen(_PATH_FTPWELCOME, "r");
623 #endif
624 	if (fd != NULL) {
625 		while (fgets(line, sizeof(line), fd) != NULL) {
626 			if ((cp = strchr(line, '\n')) != NULL)
627 				*cp = '\0';
628 			lreply(220, "%s", line);
629 		}
630 		(void) fflush(stdout);
631 		(void) fclose(fd);
632 		/* reply(220,) must follow */
633 	}
634 #ifndef VIRTUAL_HOSTING
635 	if ((hostname = malloc(MAXHOSTNAMELEN)) == NULL)
636 		fatalerror("Ran out of memory.");
637 	if (gethostname(hostname, MAXHOSTNAMELEN - 1) < 0)
638 		hostname[0] = '\0';
639 	hostname[MAXHOSTNAMELEN - 1] = '\0';
640 #endif
641 	if (hostinfo)
642 		reply(220, "%s FTP server (%s) ready.", hostname, version);
643 	else
644 		reply(220, "FTP server ready.");
645 	BLACKLIST_INIT();
646 	for (;;)
647 		(void) yyparse();
648 	/* NOTREACHED */
649 }
650 
651 static void
652 lostconn(int signo)
653 {
654 
655 	if (ftpdebug)
656 		syslog(LOG_DEBUG, "lost connection");
657 	dologout(1);
658 }
659 
660 static void
661 sigquit(int signo)
662 {
663 
664 	syslog(LOG_ERR, "got signal %d", signo);
665 	dologout(1);
666 }
667 
668 #ifdef VIRTUAL_HOSTING
669 /*
670  * read in virtual host tables (if they exist)
671  */
672 
673 static void
674 inithosts(int family)
675 {
676 	int insert;
677 	size_t len;
678 	FILE *fp;
679 	char *cp, *mp, *line;
680 	char *hostname;
681 	char *vhost, *anonuser, *statfile, *welcome, *loginmsg;
682 	struct ftphost *hrp, *lhrp;
683 	struct addrinfo hints, *res, *ai;
684 
685 	/*
686 	 * Fill in the default host information
687 	 */
688 	if ((hostname = malloc(MAXHOSTNAMELEN)) == NULL)
689 		fatalerror("Ran out of memory.");
690 	if (gethostname(hostname, MAXHOSTNAMELEN - 1) < 0)
691 		hostname[0] = '\0';
692 	hostname[MAXHOSTNAMELEN - 1] = '\0';
693 	if ((hrp = malloc(sizeof(struct ftphost))) == NULL)
694 		fatalerror("Ran out of memory.");
695 	hrp->hostname = hostname;
696 	hrp->hostinfo = NULL;
697 
698 	memset(&hints, 0, sizeof(hints));
699 	hints.ai_flags = AI_PASSIVE;
700 	hints.ai_family = family;
701 	hints.ai_socktype = SOCK_STREAM;
702 	if (getaddrinfo(hrp->hostname, NULL, &hints, &res) == 0)
703 		hrp->hostinfo = res;
704 	hrp->statfile = _PATH_FTPDSTATFILE;
705 	hrp->welcome  = _PATH_FTPWELCOME;
706 	hrp->loginmsg = _PATH_FTPLOGINMESG;
707 	hrp->anonuser = "ftp";
708 	hrp->next = NULL;
709 	thishost = firsthost = lhrp = hrp;
710 	if ((fp = fopen(_PATH_FTPHOSTS, "r")) != NULL) {
711 		int addrsize, gothost;
712 		void *addr;
713 		struct hostent *hp;
714 
715 		while ((line = fgetln(fp, &len)) != NULL) {
716 			int	i, hp_error;
717 
718 			/* skip comments */
719 			if (line[0] == '#')
720 				continue;
721 			if (line[len - 1] == '\n') {
722 				line[len - 1] = '\0';
723 				mp = NULL;
724 			} else {
725 				if ((mp = malloc(len + 1)) == NULL)
726 					fatalerror("Ran out of memory.");
727 				memcpy(mp, line, len);
728 				mp[len] = '\0';
729 				line = mp;
730 			}
731 			cp = strtok(line, " \t");
732 			/* skip empty lines */
733 			if (cp == NULL)
734 				goto nextline;
735 			vhost = cp;
736 
737 			/* set defaults */
738 			anonuser = "ftp";
739 			statfile = _PATH_FTPDSTATFILE;
740 			welcome  = _PATH_FTPWELCOME;
741 			loginmsg = _PATH_FTPLOGINMESG;
742 
743 			/*
744 			 * Preparse the line so we can use its info
745 			 * for all the addresses associated with
746 			 * the virtual host name.
747 			 * Field 0, the virtual host name, is special:
748 			 * it's already parsed off and will be strdup'ed
749 			 * later, after we know its canonical form.
750 			 */
751 			for (i = 1; i < 5 && (cp = strtok(NULL, " \t")); i++)
752 				if (*cp != '-' && (cp = strdup(cp)))
753 					switch (i) {
754 					case 1:	/* anon user permissions */
755 						anonuser = cp;
756 						break;
757 					case 2: /* statistics file */
758 						statfile = cp;
759 						break;
760 					case 3: /* welcome message */
761 						welcome  = cp;
762 						break;
763 					case 4: /* login message */
764 						loginmsg = cp;
765 						break;
766 					default: /* programming error */
767 						abort();
768 						/* NOTREACHED */
769 					}
770 
771 			hints.ai_flags = AI_PASSIVE;
772 			hints.ai_family = family;
773 			hints.ai_socktype = SOCK_STREAM;
774 			if (getaddrinfo(vhost, NULL, &hints, &res) != 0)
775 				goto nextline;
776 			for (ai = res; ai != NULL && ai->ai_addr != NULL;
777 			     ai = ai->ai_next) {
778 
779 			gothost = 0;
780 			for (hrp = firsthost; hrp != NULL; hrp = hrp->next) {
781 				struct addrinfo *hi;
782 
783 				for (hi = hrp->hostinfo; hi != NULL;
784 				     hi = hi->ai_next)
785 					if (hi->ai_addrlen == ai->ai_addrlen &&
786 					    memcmp(hi->ai_addr,
787 						   ai->ai_addr,
788 						   ai->ai_addr->sa_len) == 0) {
789 						gothost++;
790 						break;
791 					}
792 				if (gothost)
793 					break;
794 			}
795 			if (hrp == NULL) {
796 				if ((hrp = malloc(sizeof(struct ftphost))) == NULL)
797 					goto nextline;
798 				hrp->hostname = NULL;
799 				insert = 1;
800 			} else {
801 				if (hrp->hostinfo && hrp->hostinfo != res)
802 					freeaddrinfo(hrp->hostinfo);
803 				insert = 0; /* host already in the chain */
804 			}
805 			hrp->hostinfo = res;
806 
807 			/*
808 			 * determine hostname to use.
809 			 * force defined name if there is a valid alias
810 			 * otherwise fallback to primary hostname
811 			 */
812 			/* XXX: getaddrinfo() can't do alias check */
813 			switch(hrp->hostinfo->ai_family) {
814 			case AF_INET:
815 				addr = &((struct sockaddr_in *)hrp->hostinfo->ai_addr)->sin_addr;
816 				addrsize = sizeof(struct in_addr);
817 				break;
818 			case AF_INET6:
819 				addr = &((struct sockaddr_in6 *)hrp->hostinfo->ai_addr)->sin6_addr;
820 				addrsize = sizeof(struct in6_addr);
821 				break;
822 			default:
823 				/* should not reach here */
824 				freeaddrinfo(hrp->hostinfo);
825 				if (insert)
826 					free(hrp); /*not in chain, can free*/
827 				else
828 					hrp->hostinfo = NULL; /*mark as blank*/
829 				goto nextline;
830 				/* NOTREACHED */
831 			}
832 			if ((hp = getipnodebyaddr(addr, addrsize,
833 						  hrp->hostinfo->ai_family,
834 						  &hp_error)) != NULL) {
835 				if (strcmp(vhost, hp->h_name) != 0) {
836 					if (hp->h_aliases == NULL)
837 						vhost = hp->h_name;
838 					else {
839 						i = 0;
840 						while (hp->h_aliases[i] &&
841 						       strcmp(vhost, hp->h_aliases[i]) != 0)
842 							++i;
843 						if (hp->h_aliases[i] == NULL)
844 							vhost = hp->h_name;
845 					}
846 				}
847 			}
848 			if (hrp->hostname &&
849 			    strcmp(hrp->hostname, vhost) != 0) {
850 				free(hrp->hostname);
851 				hrp->hostname = NULL;
852 			}
853 			if (hrp->hostname == NULL &&
854 			    (hrp->hostname = strdup(vhost)) == NULL) {
855 				freeaddrinfo(hrp->hostinfo);
856 				hrp->hostinfo = NULL; /* mark as blank */
857 				if (hp)
858 					freehostent(hp);
859 				goto nextline;
860 			}
861 			hrp->anonuser = anonuser;
862 			hrp->statfile = statfile;
863 			hrp->welcome  = welcome;
864 			hrp->loginmsg = loginmsg;
865 			if (insert) {
866 				hrp->next  = NULL;
867 				lhrp->next = hrp;
868 				lhrp = hrp;
869 			}
870 			if (hp)
871 				freehostent(hp);
872 		      }
873 nextline:
874 			if (mp)
875 				free(mp);
876 		}
877 		(void) fclose(fp);
878 	}
879 }
880 
881 static void
882 selecthost(union sockunion *su)
883 {
884 	struct ftphost	*hrp;
885 	u_int16_t port;
886 #ifdef INET6
887 	struct in6_addr *mapped_in6 = NULL;
888 #endif
889 	struct addrinfo *hi;
890 
891 #ifdef INET6
892 	/*
893 	 * XXX IPv4 mapped IPv6 addr consideraton,
894 	 * specified in rfc2373.
895 	 */
896 	if (su->su_family == AF_INET6 &&
897 	    IN6_IS_ADDR_V4MAPPED(&su->su_sin6.sin6_addr))
898 		mapped_in6 = &su->su_sin6.sin6_addr;
899 #endif
900 
901 	hrp = thishost = firsthost;	/* default */
902 	port = su->su_port;
903 	su->su_port = 0;
904 	while (hrp != NULL) {
905 	    for (hi = hrp->hostinfo; hi != NULL; hi = hi->ai_next) {
906 		if (memcmp(su, hi->ai_addr, hi->ai_addrlen) == 0) {
907 			thishost = hrp;
908 			goto found;
909 		}
910 #ifdef INET6
911 		/* XXX IPv4 mapped IPv6 addr consideraton */
912 		if (hi->ai_addr->sa_family == AF_INET && mapped_in6 != NULL &&
913 		    (memcmp(&mapped_in6->s6_addr[12],
914 			    &((struct sockaddr_in *)hi->ai_addr)->sin_addr,
915 			    sizeof(struct in_addr)) == 0)) {
916 			thishost = hrp;
917 			goto found;
918 		}
919 #endif
920 	    }
921 	    hrp = hrp->next;
922 	}
923 found:
924 	su->su_port = port;
925 	/* setup static variables as appropriate */
926 	hostname = thishost->hostname;
927 	ftpuser = thishost->anonuser;
928 }
929 #endif
930 
931 /*
932  * Helper function for sgetpwnam().
933  */
934 static char *
935 sgetsave(char *s)
936 {
937 	char *new = malloc(strlen(s) + 1);
938 
939 	if (new == NULL) {
940 		reply(421, "Ran out of memory.");
941 		dologout(1);
942 		/* NOTREACHED */
943 	}
944 	(void) strcpy(new, s);
945 	return (new);
946 }
947 
948 /*
949  * Save the result of a getpwnam.  Used for USER command, since
950  * the data returned must not be clobbered by any other command
951  * (e.g., globbing).
952  * NB: The data returned by sgetpwnam() will remain valid until
953  * the next call to this function.  Its difference from getpwnam()
954  * is that sgetpwnam() is known to be called from ftpd code only.
955  */
956 static struct passwd *
957 sgetpwnam(char *name)
958 {
959 	static struct passwd save;
960 	struct passwd *p;
961 
962 	if ((p = getpwnam(name)) == NULL)
963 		return (p);
964 	if (save.pw_name) {
965 		free(save.pw_name);
966 		free(save.pw_passwd);
967 		free(save.pw_class);
968 		free(save.pw_gecos);
969 		free(save.pw_dir);
970 		free(save.pw_shell);
971 	}
972 	save = *p;
973 	save.pw_name = sgetsave(p->pw_name);
974 	save.pw_passwd = sgetsave(p->pw_passwd);
975 	save.pw_class = sgetsave(p->pw_class);
976 	save.pw_gecos = sgetsave(p->pw_gecos);
977 	save.pw_dir = sgetsave(p->pw_dir);
978 	save.pw_shell = sgetsave(p->pw_shell);
979 	return (&save);
980 }
981 
982 static int login_attempts;	/* number of failed login attempts */
983 static int askpasswd;		/* had user command, ask for passwd */
984 static char curname[MAXLOGNAME];	/* current USER name */
985 
986 /*
987  * USER command.
988  * Sets global passwd pointer pw if named account exists and is acceptable;
989  * sets askpasswd if a PASS command is expected.  If logged in previously,
990  * need to reset state.  If name is "ftp" or "anonymous", the name is not in
991  * _PATH_FTPUSERS, and ftp account exists, set guest and pw, then just return.
992  * If account doesn't exist, ask for passwd anyway.  Otherwise, check user
993  * requesting login privileges.  Disallow anyone who does not have a standard
994  * shell as returned by getusershell().  Disallow anyone mentioned in the file
995  * _PATH_FTPUSERS to allow people such as root and uucp to be avoided.
996  */
997 void
998 user(char *name)
999 {
1000 	int ecode;
1001 	char *cp, *shell;
1002 
1003 	if (logged_in) {
1004 		if (guest) {
1005 			reply(530, "Can't change user from guest login.");
1006 			return;
1007 		} else if (dochroot) {
1008 			reply(530, "Can't change user from chroot user.");
1009 			return;
1010 		}
1011 		end_login();
1012 	}
1013 
1014 	guest = 0;
1015 #ifdef VIRTUAL_HOSTING
1016 	pw = sgetpwnam(thishost->anonuser);
1017 #else
1018 	pw = sgetpwnam("ftp");
1019 #endif
1020 	if (strcmp(name, "ftp") == 0 || strcmp(name, "anonymous") == 0) {
1021 		if (checkuser(_PATH_FTPUSERS, "ftp", 0, NULL, &ecode) ||
1022 		    (ecode != 0 && ecode != ENOENT))
1023 			reply(530, "User %s access denied.", name);
1024 		else if (checkuser(_PATH_FTPUSERS, "anonymous", 0, NULL, &ecode) ||
1025 		    (ecode != 0 && ecode != ENOENT))
1026 			reply(530, "User %s access denied.", name);
1027 		else if (pw != NULL) {
1028 			guest = 1;
1029 			askpasswd = 1;
1030 			reply(331,
1031 			"Guest login ok, send your email address as password.");
1032 		} else
1033 			reply(530, "User %s unknown.", name);
1034 		if (!askpasswd && logging)
1035 			syslog(LOG_NOTICE,
1036 			    "ANONYMOUS FTP LOGIN REFUSED FROM %s", remotehost);
1037 		return;
1038 	}
1039 	if (anon_only != 0) {
1040 		reply(530, "Sorry, only anonymous ftp allowed.");
1041 		return;
1042 	}
1043 
1044 	if ((pw = sgetpwnam(name))) {
1045 		if ((shell = pw->pw_shell) == NULL || *shell == 0)
1046 			shell = _PATH_BSHELL;
1047 		setusershell();
1048 		while ((cp = getusershell()) != NULL)
1049 			if (strcmp(cp, shell) == 0)
1050 				break;
1051 		endusershell();
1052 
1053 		if (cp == NULL ||
1054 		    (checkuser(_PATH_FTPUSERS, name, 1, NULL, &ecode) ||
1055 		    (ecode != 0 && ecode != ENOENT))) {
1056 			reply(530, "User %s access denied.", name);
1057 			if (logging)
1058 				syslog(LOG_NOTICE,
1059 				    "FTP LOGIN REFUSED FROM %s, %s",
1060 				    remotehost, name);
1061 			pw = NULL;
1062 			return;
1063 		}
1064 	}
1065 	if (logging)
1066 		strlcpy(curname, name, sizeof(curname));
1067 
1068 	pwok = 0;
1069 #ifdef USE_PAM
1070 	/* XXX Kluge! The conversation mechanism needs to be fixed. */
1071 #endif
1072 	if (opiechallenge(&opiedata, name, opieprompt) == 0) {
1073 		pwok = (pw != NULL) &&
1074 		       opieaccessfile(remotehost) &&
1075 		       opiealways(pw->pw_dir);
1076 		reply(331, "Response to %s %s for %s.",
1077 		      opieprompt, pwok ? "requested" : "required", name);
1078 	} else {
1079 		pwok = 1;
1080 		reply(331, "Password required for %s.", name);
1081 	}
1082 	askpasswd = 1;
1083 	/*
1084 	 * Delay before reading passwd after first failed
1085 	 * attempt to slow down passwd-guessing programs.
1086 	 */
1087 	if (login_attempts)
1088 		sleep(login_attempts);
1089 }
1090 
1091 /*
1092  * Check if a user is in the file "fname",
1093  * return a pointer to a malloc'd string with the rest
1094  * of the matching line in "residue" if not NULL.
1095  */
1096 static int
1097 checkuser(char *fname, char *name, int pwset, char **residue, int *ecode)
1098 {
1099 	FILE *fd;
1100 	int found = 0;
1101 	size_t len;
1102 	char *line, *mp, *p;
1103 
1104 	if (ecode != NULL)
1105 		*ecode = 0;
1106 	if ((fd = fopen(fname, "r")) != NULL) {
1107 		while (!found && (line = fgetln(fd, &len)) != NULL) {
1108 			/* skip comments */
1109 			if (line[0] == '#')
1110 				continue;
1111 			if (line[len - 1] == '\n') {
1112 				line[len - 1] = '\0';
1113 				mp = NULL;
1114 			} else {
1115 				if ((mp = malloc(len + 1)) == NULL)
1116 					fatalerror("Ran out of memory.");
1117 				memcpy(mp, line, len);
1118 				mp[len] = '\0';
1119 				line = mp;
1120 			}
1121 			/* avoid possible leading and trailing whitespace */
1122 			p = strtok(line, " \t");
1123 			/* skip empty lines */
1124 			if (p == NULL)
1125 				goto nextline;
1126 			/*
1127 			 * if first chr is '@', check group membership
1128 			 */
1129 			if (p[0] == '@') {
1130 				int i = 0;
1131 				struct group *grp;
1132 
1133 				if (p[1] == '\0') /* single @ matches anyone */
1134 					found = 1;
1135 				else {
1136 					if ((grp = getgrnam(p+1)) == NULL)
1137 						goto nextline;
1138 					/*
1139 					 * Check user's default group
1140 					 */
1141 					if (pwset && grp->gr_gid == pw->pw_gid)
1142 						found = 1;
1143 					/*
1144 					 * Check supplementary groups
1145 					 */
1146 					while (!found && grp->gr_mem[i])
1147 						found = strcmp(name,
1148 							grp->gr_mem[i++])
1149 							== 0;
1150 				}
1151 			}
1152 			/*
1153 			 * Otherwise, just check for username match
1154 			 */
1155 			else
1156 				found = strcmp(p, name) == 0;
1157 			/*
1158 			 * Save the rest of line to "residue" if matched
1159 			 */
1160 			if (found && residue) {
1161 				if ((p = strtok(NULL, "")) != NULL)
1162 					p += strspn(p, " \t");
1163 				if (p && *p) {
1164 				 	if ((*residue = strdup(p)) == NULL)
1165 						fatalerror("Ran out of memory.");
1166 				} else
1167 					*residue = NULL;
1168 			}
1169 nextline:
1170 			if (mp)
1171 				free(mp);
1172 		}
1173 		(void) fclose(fd);
1174 	} else if (ecode != NULL)
1175 		*ecode = errno;
1176 	return (found);
1177 }
1178 
1179 /*
1180  * Terminate login as previous user, if any, resetting state;
1181  * used when USER command is given or login fails.
1182  */
1183 static void
1184 end_login(void)
1185 {
1186 #ifdef USE_PAM
1187 	int e;
1188 #endif
1189 
1190 	(void) seteuid(0);
1191 #ifdef	LOGIN_CAP
1192 	setusercontext(NULL, getpwuid(0), 0, LOGIN_SETALL & ~(LOGIN_SETLOGIN |
1193 		       LOGIN_SETUSER | LOGIN_SETGROUP | LOGIN_SETPATH |
1194 		       LOGIN_SETENV));
1195 #endif
1196 	if (logged_in && dowtmp)
1197 		ftpd_logwtmp(wtmpid, NULL, NULL);
1198 	pw = NULL;
1199 #ifdef USE_PAM
1200 	if (pamh) {
1201 		if ((e = pam_setcred(pamh, PAM_DELETE_CRED)) != PAM_SUCCESS)
1202 			syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, e));
1203 		if ((e = pam_close_session(pamh,0)) != PAM_SUCCESS)
1204 			syslog(LOG_ERR, "pam_close_session: %s", pam_strerror(pamh, e));
1205 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS)
1206 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1207 		pamh = NULL;
1208 	}
1209 #endif
1210 	logged_in = 0;
1211 	guest = 0;
1212 	dochroot = 0;
1213 }
1214 
1215 #ifdef USE_PAM
1216 
1217 /*
1218  * the following code is stolen from imap-uw PAM authentication module and
1219  * login.c
1220  */
1221 #define COPY_STRING(s) (s ? strdup(s) : NULL)
1222 
1223 struct cred_t {
1224 	const char *uname;		/* user name */
1225 	const char *pass;		/* password */
1226 };
1227 typedef struct cred_t cred_t;
1228 
1229 static int
1230 auth_conv(int num_msg, const struct pam_message **msg,
1231 	  struct pam_response **resp, void *appdata)
1232 {
1233 	int i;
1234 	cred_t *cred = (cred_t *) appdata;
1235 	struct pam_response *reply;
1236 
1237 	reply = calloc(num_msg, sizeof *reply);
1238 	if (reply == NULL)
1239 		return PAM_BUF_ERR;
1240 
1241 	for (i = 0; i < num_msg; i++) {
1242 		switch (msg[i]->msg_style) {
1243 		case PAM_PROMPT_ECHO_ON:	/* assume want user name */
1244 			reply[i].resp_retcode = PAM_SUCCESS;
1245 			reply[i].resp = COPY_STRING(cred->uname);
1246 			/* PAM frees resp. */
1247 			break;
1248 		case PAM_PROMPT_ECHO_OFF:	/* assume want password */
1249 			reply[i].resp_retcode = PAM_SUCCESS;
1250 			reply[i].resp = COPY_STRING(cred->pass);
1251 			/* PAM frees resp. */
1252 			break;
1253 		case PAM_TEXT_INFO:
1254 		case PAM_ERROR_MSG:
1255 			reply[i].resp_retcode = PAM_SUCCESS;
1256 			reply[i].resp = NULL;
1257 			break;
1258 		default:			/* unknown message style */
1259 			free(reply);
1260 			return PAM_CONV_ERR;
1261 		}
1262 	}
1263 
1264 	*resp = reply;
1265 	return PAM_SUCCESS;
1266 }
1267 
1268 /*
1269  * Attempt to authenticate the user using PAM.  Returns 0 if the user is
1270  * authenticated, or 1 if not authenticated.  If some sort of PAM system
1271  * error occurs (e.g., the "/etc/pam.conf" file is missing) then this
1272  * function returns -1.  This can be used as an indication that we should
1273  * fall back to a different authentication mechanism.
1274  */
1275 static int
1276 auth_pam(struct passwd **ppw, const char *pass)
1277 {
1278 	const char *tmpl_user;
1279 	const void *item;
1280 	int rval;
1281 	int e;
1282 	cred_t auth_cred = { (*ppw)->pw_name, pass };
1283 	struct pam_conv conv = { &auth_conv, &auth_cred };
1284 
1285 	e = pam_start("ftpd", (*ppw)->pw_name, &conv, &pamh);
1286 	if (e != PAM_SUCCESS) {
1287 		/*
1288 		 * In OpenPAM, it's OK to pass NULL to pam_strerror()
1289 		 * if context creation has failed in the first place.
1290 		 */
1291 		syslog(LOG_ERR, "pam_start: %s", pam_strerror(NULL, e));
1292 		return -1;
1293 	}
1294 
1295 	e = pam_set_item(pamh, PAM_RHOST, remotehost);
1296 	if (e != PAM_SUCCESS) {
1297 		syslog(LOG_ERR, "pam_set_item(PAM_RHOST): %s",
1298 			pam_strerror(pamh, e));
1299 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
1300 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1301 		}
1302 		pamh = NULL;
1303 		return -1;
1304 	}
1305 
1306 	e = pam_authenticate(pamh, 0);
1307 	switch (e) {
1308 	case PAM_SUCCESS:
1309 		/*
1310 		 * With PAM we support the concept of a "template"
1311 		 * user.  The user enters a login name which is
1312 		 * authenticated by PAM, usually via a remote service
1313 		 * such as RADIUS or TACACS+.  If authentication
1314 		 * succeeds, a different but related "template" name
1315 		 * is used for setting the credentials, shell, and
1316 		 * home directory.  The name the user enters need only
1317 		 * exist on the remote authentication server, but the
1318 		 * template name must be present in the local password
1319 		 * database.
1320 		 *
1321 		 * This is supported by two various mechanisms in the
1322 		 * individual modules.  However, from the application's
1323 		 * point of view, the template user is always passed
1324 		 * back as a changed value of the PAM_USER item.
1325 		 */
1326 		if ((e = pam_get_item(pamh, PAM_USER, &item)) ==
1327 		    PAM_SUCCESS) {
1328 			tmpl_user = (const char *) item;
1329 			if (strcmp((*ppw)->pw_name, tmpl_user) != 0)
1330 				*ppw = getpwnam(tmpl_user);
1331 		} else
1332 			syslog(LOG_ERR, "Couldn't get PAM_USER: %s",
1333 			    pam_strerror(pamh, e));
1334 		rval = 0;
1335 		break;
1336 
1337 	case PAM_AUTH_ERR:
1338 	case PAM_USER_UNKNOWN:
1339 	case PAM_MAXTRIES:
1340 		rval = 1;
1341 		break;
1342 
1343 	default:
1344 		syslog(LOG_ERR, "pam_authenticate: %s", pam_strerror(pamh, e));
1345 		rval = -1;
1346 		break;
1347 	}
1348 
1349 	if (rval == 0) {
1350 		e = pam_acct_mgmt(pamh, 0);
1351 		if (e != PAM_SUCCESS) {
1352 			syslog(LOG_ERR, "pam_acct_mgmt: %s",
1353 						pam_strerror(pamh, e));
1354 			rval = 1;
1355 		}
1356 	}
1357 
1358 	if (rval != 0) {
1359 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
1360 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1361 		}
1362 		pamh = NULL;
1363 	}
1364 	return rval;
1365 }
1366 
1367 #endif /* USE_PAM */
1368 
1369 void
1370 pass(char *passwd)
1371 {
1372 	int rval, ecode;
1373 	FILE *fd;
1374 #ifdef	LOGIN_CAP
1375 	login_cap_t *lc = NULL;
1376 #endif
1377 #ifdef USE_PAM
1378 	int e;
1379 #endif
1380 	char *residue = NULL;
1381 	char *xpasswd;
1382 
1383 	if (logged_in || askpasswd == 0) {
1384 		reply(503, "Login with USER first.");
1385 		return;
1386 	}
1387 	askpasswd = 0;
1388 	if (!guest) {		/* "ftp" is only account allowed no password */
1389 		if (pw == NULL) {
1390 			rval = 1;	/* failure below */
1391 			goto skip;
1392 		}
1393 #ifdef USE_PAM
1394 		rval = auth_pam(&pw, passwd);
1395 		if (rval >= 0) {
1396 			opieunlock();
1397 			goto skip;
1398 		}
1399 #endif
1400 		if (opieverify(&opiedata, passwd) == 0)
1401 			xpasswd = pw->pw_passwd;
1402 		else if (pwok) {
1403 			xpasswd = crypt(passwd, pw->pw_passwd);
1404 			if (passwd[0] == '\0' && pw->pw_passwd[0] != '\0')
1405 				xpasswd = ":";
1406 		} else {
1407 			rval = 1;
1408 			goto skip;
1409 		}
1410 		rval = strcmp(pw->pw_passwd, xpasswd);
1411 		if (pw->pw_expire && time(NULL) >= pw->pw_expire)
1412 			rval = 1;	/* failure */
1413 skip:
1414 		/*
1415 		 * If rval == 1, the user failed the authentication check
1416 		 * above.  If rval == 0, either PAM or local authentication
1417 		 * succeeded.
1418 		 */
1419 		if (rval) {
1420 			reply(530, "Login incorrect.");
1421 			BLACKLIST_NOTIFY(BLACKLIST_AUTH_FAIL, STDIN_FILENO, "Login incorrect");
1422 			if (logging) {
1423 				syslog(LOG_NOTICE,
1424 				    "FTP LOGIN FAILED FROM %s",
1425 				    remotehost);
1426 				syslog(LOG_AUTHPRIV | LOG_NOTICE,
1427 				    "FTP LOGIN FAILED FROM %s, %s",
1428 				    remotehost, curname);
1429 			}
1430 			pw = NULL;
1431 			if (login_attempts++ >= 5) {
1432 				syslog(LOG_NOTICE,
1433 				    "repeated login failures from %s",
1434 				    remotehost);
1435 				exit(0);
1436 			}
1437 			return;
1438 		} else {
1439 			BLACKLIST_NOTIFY(BLACKLIST_AUTH_OK, STDIN_FILENO, "Login successful");
1440 		}
1441 	}
1442 	login_attempts = 0;		/* this time successful */
1443 	if (setegid(pw->pw_gid) < 0) {
1444 		reply(550, "Can't set gid.");
1445 		return;
1446 	}
1447 	/* May be overridden by login.conf */
1448 	(void) umask(defumask);
1449 #ifdef	LOGIN_CAP
1450 	if ((lc = login_getpwclass(pw)) != NULL) {
1451 		char	remote_ip[NI_MAXHOST];
1452 
1453 		if (getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
1454 			remote_ip, sizeof(remote_ip) - 1, NULL, 0,
1455 			NI_NUMERICHOST))
1456 				*remote_ip = 0;
1457 		remote_ip[sizeof(remote_ip) - 1] = 0;
1458 		if (!auth_hostok(lc, remotehost, remote_ip)) {
1459 			syslog(LOG_INFO|LOG_AUTH,
1460 			    "FTP LOGIN FAILED (HOST) as %s: permission denied.",
1461 			    pw->pw_name);
1462 			reply(530, "Permission denied.");
1463 			pw = NULL;
1464 			return;
1465 		}
1466 		if (!auth_timeok(lc, time(NULL))) {
1467 			reply(530, "Login not available right now.");
1468 			pw = NULL;
1469 			return;
1470 		}
1471 	}
1472 	setusercontext(lc, pw, 0, LOGIN_SETALL &
1473 		       ~(LOGIN_SETRESOURCES | LOGIN_SETUSER | LOGIN_SETPATH | LOGIN_SETENV));
1474 #else
1475 	setlogin(pw->pw_name);
1476 	(void) initgroups(pw->pw_name, pw->pw_gid);
1477 #endif
1478 
1479 #ifdef USE_PAM
1480 	if (pamh) {
1481 		if ((e = pam_open_session(pamh, 0)) != PAM_SUCCESS) {
1482 			syslog(LOG_ERR, "pam_open_session: %s", pam_strerror(pamh, e));
1483 		} else if ((e = pam_setcred(pamh, PAM_ESTABLISH_CRED)) != PAM_SUCCESS) {
1484 			syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, e));
1485 		}
1486 	}
1487 #endif
1488 
1489 	dochroot =
1490 		checkuser(_PATH_FTPCHROOT, pw->pw_name, 1, &residue, &ecode)
1491 #ifdef	LOGIN_CAP	/* Allow login.conf configuration as well */
1492 		|| login_getcapbool(lc, "ftp-chroot", 0)
1493 #endif
1494 	;
1495 	/*
1496 	 * It is possible that checkuser() failed to open the chroot file.
1497 	 * If this is the case, report that logins are un-available, since we
1498 	 * have no way of checking whether or not the user should be chrooted.
1499 	 * We ignore ENOENT since it is not required that this file be present.
1500 	 */
1501 	if (ecode != 0 && ecode != ENOENT) {
1502 		reply(530, "Login not available right now.");
1503 		return;
1504 	}
1505 	chrootdir = NULL;
1506 
1507 	/* Disable wtmp logging when chrooting. */
1508 	if (dochroot || guest)
1509 		dowtmp = 0;
1510 	if (dowtmp)
1511 		ftpd_logwtmp(wtmpid, pw->pw_name,
1512 		    (struct sockaddr *)&his_addr);
1513 	logged_in = 1;
1514 
1515 #ifdef	LOGIN_CAP
1516 	setusercontext(lc, pw, 0, LOGIN_SETRESOURCES);
1517 #endif
1518 
1519 	if (guest && stats && statfd < 0) {
1520 #ifdef VIRTUAL_HOSTING
1521 		statfd = open(thishost->statfile, O_WRONLY|O_APPEND);
1522 #else
1523 		statfd = open(_PATH_FTPDSTATFILE, O_WRONLY|O_APPEND);
1524 #endif
1525 		if (statfd < 0)
1526 			stats = 0;
1527 	}
1528 
1529 	/*
1530 	 * For a chrooted local user,
1531 	 * a) see whether ftpchroot(5) specifies a chroot directory,
1532 	 * b) extract the directory pathname from the line,
1533 	 * c) expand it to the absolute pathname if necessary.
1534 	 */
1535 	if (dochroot && residue &&
1536 	    (chrootdir = strtok(residue, " \t")) != NULL) {
1537 		if (chrootdir[0] != '/')
1538 			asprintf(&chrootdir, "%s/%s", pw->pw_dir, chrootdir);
1539 		else
1540 			chrootdir = strdup(chrootdir); /* make it permanent */
1541 		if (chrootdir == NULL)
1542 			fatalerror("Ran out of memory.");
1543 	}
1544 	if (guest || dochroot) {
1545 		/*
1546 		 * If no chroot directory set yet, use the login directory.
1547 		 * Copy it so it can be modified while pw->pw_dir stays intact.
1548 		 */
1549 		if (chrootdir == NULL &&
1550 		    (chrootdir = strdup(pw->pw_dir)) == NULL)
1551 			fatalerror("Ran out of memory.");
1552 		/*
1553 		 * Check for the "/chroot/./home" syntax,
1554 		 * separate the chroot and home directory pathnames.
1555 		 */
1556 		if ((homedir = strstr(chrootdir, "/./")) != NULL) {
1557 			*(homedir++) = '\0';	/* wipe '/' */
1558 			homedir++;		/* skip '.' */
1559 		} else {
1560 			/*
1561 			 * We MUST do a chdir() after the chroot. Otherwise
1562 			 * the old current directory will be accessible as "."
1563 			 * outside the new root!
1564 			 */
1565 			homedir = "/";
1566 		}
1567 		/*
1568 		 * Finally, do chroot()
1569 		 */
1570 		if (chroot(chrootdir) < 0) {
1571 			reply(550, "Can't change root.");
1572 			goto bad;
1573 		}
1574 		__FreeBSD_libc_enter_restricted_mode();
1575 	} else	/* real user w/o chroot */
1576 		homedir = pw->pw_dir;
1577 	/*
1578 	 * Set euid *before* doing chdir() so
1579 	 * a) the user won't be carried to a directory that he couldn't reach
1580 	 *    on his own due to no permission to upper path components,
1581 	 * b) NFS mounted homedirs w/restrictive permissions will be accessible
1582 	 *    (uid 0 has no root power over NFS if not mapped explicitly.)
1583 	 */
1584 	if (seteuid(pw->pw_uid) < 0) {
1585 		if (guest || dochroot) {
1586 			fatalerror("Can't set uid.");
1587 		} else {
1588 			reply(550, "Can't set uid.");
1589 			goto bad;
1590 		}
1591 	}
1592 	/*
1593 	 * Do not allow the session to live if we're chroot()'ed and chdir()
1594 	 * fails. Otherwise the chroot jail can be escaped.
1595 	 */
1596 	if (chdir(homedir) < 0) {
1597 		if (guest || dochroot) {
1598 			fatalerror("Can't change to base directory.");
1599 		} else {
1600 			if (chdir("/") < 0) {
1601 				reply(550, "Root is inaccessible.");
1602 				goto bad;
1603 			}
1604 			lreply(230, "No directory! Logging in with home=/.");
1605 		}
1606 	}
1607 
1608 	/*
1609 	 * Display a login message, if it exists.
1610 	 * N.B. reply(230,) must follow the message.
1611 	 */
1612 #ifdef VIRTUAL_HOSTING
1613 	fd = fopen(thishost->loginmsg, "r");
1614 #else
1615 	fd = fopen(_PATH_FTPLOGINMESG, "r");
1616 #endif
1617 	if (fd != NULL) {
1618 		char *cp, line[LINE_MAX];
1619 
1620 		while (fgets(line, sizeof(line), fd) != NULL) {
1621 			if ((cp = strchr(line, '\n')) != NULL)
1622 				*cp = '\0';
1623 			lreply(230, "%s", line);
1624 		}
1625 		(void) fflush(stdout);
1626 		(void) fclose(fd);
1627 	}
1628 	if (guest) {
1629 		if (ident != NULL)
1630 			free(ident);
1631 		ident = strdup(passwd);
1632 		if (ident == NULL)
1633 			fatalerror("Ran out of memory.");
1634 
1635 		reply(230, "Guest login ok, access restrictions apply.");
1636 #ifdef SETPROCTITLE
1637 #ifdef VIRTUAL_HOSTING
1638 		if (thishost != firsthost)
1639 			snprintf(proctitle, sizeof(proctitle),
1640 				 "%s: anonymous(%s)/%s", remotehost, hostname,
1641 				 passwd);
1642 		else
1643 #endif
1644 			snprintf(proctitle, sizeof(proctitle),
1645 				 "%s: anonymous/%s", remotehost, passwd);
1646 		setproctitle("%s", proctitle);
1647 #endif /* SETPROCTITLE */
1648 		if (logging)
1649 			syslog(LOG_INFO, "ANONYMOUS FTP LOGIN FROM %s, %s",
1650 			    remotehost, passwd);
1651 	} else {
1652 		if (dochroot)
1653 			reply(230, "User %s logged in, "
1654 				   "access restrictions apply.", pw->pw_name);
1655 		else
1656 			reply(230, "User %s logged in.", pw->pw_name);
1657 
1658 #ifdef SETPROCTITLE
1659 		snprintf(proctitle, sizeof(proctitle),
1660 			 "%s: user/%s", remotehost, pw->pw_name);
1661 		setproctitle("%s", proctitle);
1662 #endif /* SETPROCTITLE */
1663 		if (logging)
1664 			syslog(LOG_INFO, "FTP LOGIN FROM %s as %s",
1665 			    remotehost, pw->pw_name);
1666 	}
1667 	if (logging && (guest || dochroot))
1668 		syslog(LOG_INFO, "session root changed to %s", chrootdir);
1669 #ifdef	LOGIN_CAP
1670 	login_close(lc);
1671 #endif
1672 	if (residue)
1673 		free(residue);
1674 	return;
1675 bad:
1676 	/* Forget all about it... */
1677 #ifdef	LOGIN_CAP
1678 	login_close(lc);
1679 #endif
1680 	if (residue)
1681 		free(residue);
1682 	end_login();
1683 }
1684 
1685 void
1686 retrieve(char *cmd, char *name)
1687 {
1688 	FILE *fin, *dout;
1689 	struct stat st;
1690 	int (*closefunc)(FILE *);
1691 	time_t start;
1692 	char line[BUFSIZ];
1693 
1694 	if (cmd == 0) {
1695 		fin = fopen(name, "r"), closefunc = fclose;
1696 		st.st_size = 0;
1697 	} else {
1698 		(void) snprintf(line, sizeof(line), cmd, name);
1699 		name = line;
1700 		fin = ftpd_popen(line, "r"), closefunc = ftpd_pclose;
1701 		st.st_size = -1;
1702 		st.st_blksize = BUFSIZ;
1703 	}
1704 	if (fin == NULL) {
1705 		if (errno != 0) {
1706 			perror_reply(550, name);
1707 			if (cmd == 0) {
1708 				LOGCMD("get", name);
1709 			}
1710 		}
1711 		return;
1712 	}
1713 	byte_count = -1;
1714 	if (cmd == 0) {
1715 		if (fstat(fileno(fin), &st) < 0) {
1716 			perror_reply(550, name);
1717 			goto done;
1718 		}
1719 		if (!S_ISREG(st.st_mode)) {
1720 			/*
1721 			 * Never sending a raw directory is a workaround
1722 			 * for buggy clients that will attempt to RETR
1723 			 * a directory before listing it, e.g., Mozilla.
1724 			 * Preventing a guest from getting irregular files
1725 			 * is a simple security measure.
1726 			 */
1727 			if (S_ISDIR(st.st_mode) || guest) {
1728 				reply(550, "%s: not a plain file.", name);
1729 				goto done;
1730 			}
1731 			st.st_size = -1;
1732 			/* st.st_blksize is set for all descriptor types */
1733 		}
1734 	}
1735 	if (restart_point) {
1736 		if (type == TYPE_A) {
1737 			off_t i, n;
1738 			int c;
1739 
1740 			n = restart_point;
1741 			i = 0;
1742 			while (i++ < n) {
1743 				if ((c=getc(fin)) == EOF) {
1744 					perror_reply(550, name);
1745 					goto done;
1746 				}
1747 				if (c == '\n')
1748 					i++;
1749 			}
1750 		} else if (lseek(fileno(fin), restart_point, L_SET) < 0) {
1751 			perror_reply(550, name);
1752 			goto done;
1753 		}
1754 	}
1755 	dout = dataconn(name, st.st_size, "w");
1756 	if (dout == NULL)
1757 		goto done;
1758 	time(&start);
1759 	send_data(fin, dout, st.st_blksize, st.st_size,
1760 		  restart_point == 0 && cmd == 0 && S_ISREG(st.st_mode));
1761 	if (cmd == 0 && guest && stats && byte_count > 0)
1762 		logxfer(name, byte_count, start);
1763 	(void) fclose(dout);
1764 	data = -1;
1765 	pdata = -1;
1766 done:
1767 	if (cmd == 0)
1768 		LOGBYTES("get", name, byte_count);
1769 	(*closefunc)(fin);
1770 }
1771 
1772 void
1773 store(char *name, char *mode, int unique)
1774 {
1775 	int fd;
1776 	FILE *fout, *din;
1777 	int (*closefunc)(FILE *);
1778 
1779 	if (*mode == 'a') {		/* APPE */
1780 		if (unique) {
1781 			/* Programming error */
1782 			syslog(LOG_ERR, "Internal: unique flag to APPE");
1783 			unique = 0;
1784 		}
1785 		if (guest && noguestmod) {
1786 			reply(550, "Appending to existing file denied.");
1787 			goto err;
1788 		}
1789 		restart_point = 0;	/* not affected by preceding REST */
1790 	}
1791 	if (unique)			/* STOU overrides REST */
1792 		restart_point = 0;
1793 	if (guest && noguestmod) {
1794 		if (restart_point) {	/* guest STOR w/REST */
1795 			reply(550, "Modifying existing file denied.");
1796 			goto err;
1797 		} else			/* treat guest STOR as STOU */
1798 			unique = 1;
1799 	}
1800 
1801 	if (restart_point)
1802 		mode = "r+";	/* so ASCII manual seek can work */
1803 	if (unique) {
1804 		if ((fd = guniquefd(name, &name)) < 0)
1805 			goto err;
1806 		fout = fdopen(fd, mode);
1807 	} else
1808 		fout = fopen(name, mode);
1809 	closefunc = fclose;
1810 	if (fout == NULL) {
1811 		perror_reply(553, name);
1812 		goto err;
1813 	}
1814 	byte_count = -1;
1815 	if (restart_point) {
1816 		if (type == TYPE_A) {
1817 			off_t i, n;
1818 			int c;
1819 
1820 			n = restart_point;
1821 			i = 0;
1822 			while (i++ < n) {
1823 				if ((c=getc(fout)) == EOF) {
1824 					perror_reply(550, name);
1825 					goto done;
1826 				}
1827 				if (c == '\n')
1828 					i++;
1829 			}
1830 			/*
1831 			 * We must do this seek to "current" position
1832 			 * because we are changing from reading to
1833 			 * writing.
1834 			 */
1835 			if (fseeko(fout, 0, SEEK_CUR) < 0) {
1836 				perror_reply(550, name);
1837 				goto done;
1838 			}
1839 		} else if (lseek(fileno(fout), restart_point, L_SET) < 0) {
1840 			perror_reply(550, name);
1841 			goto done;
1842 		}
1843 	}
1844 	din = dataconn(name, -1, "r");
1845 	if (din == NULL)
1846 		goto done;
1847 	if (receive_data(din, fout) == 0) {
1848 		if (unique)
1849 			reply(226, "Transfer complete (unique file name:%s).",
1850 			    name);
1851 		else
1852 			reply(226, "Transfer complete.");
1853 	}
1854 	(void) fclose(din);
1855 	data = -1;
1856 	pdata = -1;
1857 done:
1858 	LOGBYTES(*mode == 'a' ? "append" : "put", name, byte_count);
1859 	(*closefunc)(fout);
1860 	return;
1861 err:
1862 	LOGCMD(*mode == 'a' ? "append" : "put" , name);
1863 	return;
1864 }
1865 
1866 static FILE *
1867 getdatasock(char *mode)
1868 {
1869 	int on = 1, s, t, tries;
1870 
1871 	if (data >= 0)
1872 		return (fdopen(data, mode));
1873 
1874 	s = socket(data_dest.su_family, SOCK_STREAM, 0);
1875 	if (s < 0)
1876 		goto bad;
1877 	if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
1878 		syslog(LOG_WARNING, "data setsockopt (SO_REUSEADDR): %m");
1879 	/* anchor socket to avoid multi-homing problems */
1880 	data_source = ctrl_addr;
1881 	data_source.su_port = htons(dataport);
1882 	(void) seteuid(0);
1883 	for (tries = 1; ; tries++) {
1884 		/*
1885 		 * We should loop here since it's possible that
1886 		 * another ftpd instance has passed this point and is
1887 		 * trying to open a data connection in active mode now.
1888 		 * Until the other connection is opened, we'll be getting
1889 		 * EADDRINUSE because no SOCK_STREAM sockets in the system
1890 		 * can share both local and remote addresses, localIP:20
1891 		 * and *:* in this case.
1892 		 */
1893 		if (bind(s, (struct sockaddr *)&data_source,
1894 		    data_source.su_len) >= 0)
1895 			break;
1896 		if (errno != EADDRINUSE || tries > 10)
1897 			goto bad;
1898 		sleep(tries);
1899 	}
1900 	(void) seteuid(pw->pw_uid);
1901 #ifdef IP_TOS
1902 	if (data_source.su_family == AF_INET)
1903       {
1904 	on = IPTOS_THROUGHPUT;
1905 	if (setsockopt(s, IPPROTO_IP, IP_TOS, &on, sizeof(int)) < 0)
1906 		syslog(LOG_WARNING, "data setsockopt (IP_TOS): %m");
1907       }
1908 #endif
1909 #ifdef TCP_NOPUSH
1910 	/*
1911 	 * Turn off push flag to keep sender TCP from sending short packets
1912 	 * at the boundaries of each write().
1913 	 */
1914 	on = 1;
1915 	if (setsockopt(s, IPPROTO_TCP, TCP_NOPUSH, &on, sizeof on) < 0)
1916 		syslog(LOG_WARNING, "data setsockopt (TCP_NOPUSH): %m");
1917 #endif
1918 	return (fdopen(s, mode));
1919 bad:
1920 	/* Return the real value of errno (close may change it) */
1921 	t = errno;
1922 	(void) seteuid(pw->pw_uid);
1923 	(void) close(s);
1924 	errno = t;
1925 	return (NULL);
1926 }
1927 
1928 static FILE *
1929 dataconn(char *name, off_t size, char *mode)
1930 {
1931 	char sizebuf[32];
1932 	FILE *file;
1933 	int retry = 0, tos, conerrno;
1934 
1935 	file_size = size;
1936 	byte_count = 0;
1937 	if (size != -1)
1938 		(void) snprintf(sizebuf, sizeof(sizebuf),
1939 				" (%jd bytes)", (intmax_t)size);
1940 	else
1941 		*sizebuf = '\0';
1942 	if (pdata >= 0) {
1943 		union sockunion from;
1944 		socklen_t fromlen = ctrl_addr.su_len;
1945 		int flags, s;
1946 		struct timeval timeout;
1947 		fd_set set;
1948 
1949 		FD_ZERO(&set);
1950 		FD_SET(pdata, &set);
1951 
1952 		timeout.tv_usec = 0;
1953 		timeout.tv_sec = 120;
1954 
1955 		/*
1956 		 * Granted a socket is in the blocking I/O mode,
1957 		 * accept() will block after a successful select()
1958 		 * if the selected connection dies in between.
1959 		 * Therefore set the non-blocking I/O flag here.
1960 		 */
1961 		if ((flags = fcntl(pdata, F_GETFL, 0)) == -1 ||
1962 		    fcntl(pdata, F_SETFL, flags | O_NONBLOCK) == -1)
1963 			goto pdata_err;
1964 		if (select(pdata+1, &set, NULL, NULL, &timeout) <= 0 ||
1965 		    (s = accept(pdata, (struct sockaddr *) &from, &fromlen)) < 0)
1966 			goto pdata_err;
1967 		(void) close(pdata);
1968 		pdata = s;
1969 		/*
1970 		 * Unset the inherited non-blocking I/O flag
1971 		 * on the child socket so stdio can work on it.
1972 		 */
1973 		if ((flags = fcntl(pdata, F_GETFL, 0)) == -1 ||
1974 		    fcntl(pdata, F_SETFL, flags & ~O_NONBLOCK) == -1)
1975 			goto pdata_err;
1976 #ifdef IP_TOS
1977 		if (from.su_family == AF_INET)
1978 	      {
1979 		tos = IPTOS_THROUGHPUT;
1980 		if (setsockopt(s, IPPROTO_IP, IP_TOS, &tos, sizeof(int)) < 0)
1981 			syslog(LOG_WARNING, "pdata setsockopt (IP_TOS): %m");
1982 	      }
1983 #endif
1984 		reply(150, "Opening %s mode data connection for '%s'%s.",
1985 		     type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
1986 		return (fdopen(pdata, mode));
1987 pdata_err:
1988 		reply(425, "Can't open data connection.");
1989 		(void) close(pdata);
1990 		pdata = -1;
1991 		return (NULL);
1992 	}
1993 	if (data >= 0) {
1994 		reply(125, "Using existing data connection for '%s'%s.",
1995 		    name, sizebuf);
1996 		usedefault = 1;
1997 		return (fdopen(data, mode));
1998 	}
1999 	if (usedefault)
2000 		data_dest = his_addr;
2001 	usedefault = 1;
2002 	do {
2003 		file = getdatasock(mode);
2004 		if (file == NULL) {
2005 			char hostbuf[NI_MAXHOST], portbuf[NI_MAXSERV];
2006 
2007 			if (getnameinfo((struct sockaddr *)&data_source,
2008 				data_source.su_len,
2009 				hostbuf, sizeof(hostbuf) - 1,
2010 				portbuf, sizeof(portbuf) - 1,
2011 				NI_NUMERICHOST|NI_NUMERICSERV))
2012 					*hostbuf = *portbuf = 0;
2013 			hostbuf[sizeof(hostbuf) - 1] = 0;
2014 			portbuf[sizeof(portbuf) - 1] = 0;
2015 			reply(425, "Can't create data socket (%s,%s): %s.",
2016 				hostbuf, portbuf, strerror(errno));
2017 			return (NULL);
2018 		}
2019 		data = fileno(file);
2020 		conerrno = 0;
2021 		if (connect(data, (struct sockaddr *)&data_dest,
2022 		    data_dest.su_len) == 0)
2023 			break;
2024 		conerrno = errno;
2025 		(void) fclose(file);
2026 		data = -1;
2027 		if (conerrno == EADDRINUSE) {
2028 			sleep(swaitint);
2029 			retry += swaitint;
2030 		} else {
2031 			break;
2032 		}
2033 	} while (retry <= swaitmax);
2034 	if (conerrno != 0) {
2035 		reply(425, "Can't build data connection: %s.",
2036 			   strerror(conerrno));
2037 		return (NULL);
2038 	}
2039 	reply(150, "Opening %s mode data connection for '%s'%s.",
2040 	     type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
2041 	return (file);
2042 }
2043 
2044 /*
2045  * A helper macro to avoid code duplication
2046  * in send_data() and receive_data().
2047  *
2048  * XXX We have to block SIGURG during putc() because BSD stdio
2049  * is unable to restart interrupted write operations and hence
2050  * the entire buffer contents will be lost as soon as a write()
2051  * call indicates EINTR to stdio.
2052  */
2053 #define FTPD_PUTC(ch, file, label)					\
2054 	do {								\
2055 		int ret;						\
2056 									\
2057 		do {							\
2058 			START_UNSAFE;					\
2059 			ret = putc((ch), (file));			\
2060 			END_UNSAFE;					\
2061 			CHECKOOB(return (-1))				\
2062 			else if (ferror(file))				\
2063 				goto label;				\
2064 			clearerr(file);					\
2065 		} while (ret == EOF);					\
2066 	} while (0)
2067 
2068 /*
2069  * Transfer the contents of "instr" to "outstr" peer using the appropriate
2070  * encapsulation of the data subject to Mode, Structure, and Type.
2071  *
2072  * NB: Form isn't handled.
2073  */
2074 static int
2075 send_data(FILE *instr, FILE *outstr, size_t blksize, off_t filesize, int isreg)
2076 {
2077 	int c, cp, filefd, netfd;
2078 	char *buf;
2079 
2080 	STARTXFER;
2081 
2082 	switch (type) {
2083 
2084 	case TYPE_A:
2085 		cp = EOF;
2086 		for (;;) {
2087 			c = getc(instr);
2088 			CHECKOOB(return (-1))
2089 			else if (c == EOF && ferror(instr))
2090 				goto file_err;
2091 			if (c == EOF) {
2092 				if (ferror(instr)) {	/* resume after OOB */
2093 					clearerr(instr);
2094 					continue;
2095 				}
2096 				if (feof(instr))	/* EOF */
2097 					break;
2098 				syslog(LOG_ERR, "Internal: impossible condition"
2099 						" on file after getc()");
2100 				goto file_err;
2101 			}
2102 			if (c == '\n' && cp != '\r') {
2103 				FTPD_PUTC('\r', outstr, data_err);
2104 				byte_count++;
2105 			}
2106 			FTPD_PUTC(c, outstr, data_err);
2107 			byte_count++;
2108 			cp = c;
2109 		}
2110 #ifdef notyet	/* BSD stdio isn't ready for that */
2111 		while (fflush(outstr) == EOF) {
2112 			CHECKOOB(return (-1))
2113 			else
2114 				goto data_err;
2115 			clearerr(outstr);
2116 		}
2117 		ENDXFER;
2118 #else
2119 		ENDXFER;
2120 		if (fflush(outstr) == EOF)
2121 			goto data_err;
2122 #endif
2123 		reply(226, "Transfer complete.");
2124 		return (0);
2125 
2126 	case TYPE_I:
2127 	case TYPE_L:
2128 		/*
2129 		 * isreg is only set if we are not doing restart and we
2130 		 * are sending a regular file
2131 		 */
2132 		netfd = fileno(outstr);
2133 		filefd = fileno(instr);
2134 
2135 		if (isreg) {
2136 			char *msg = "Transfer complete.";
2137 			off_t cnt, offset;
2138 			int err;
2139 
2140 			cnt = offset = 0;
2141 
2142 			while (filesize > 0) {
2143 				err = sendfile(filefd, netfd, offset, 0,
2144 					       NULL, &cnt, 0);
2145 				/*
2146 				 * Calculate byte_count before OOB processing.
2147 				 * It can be used in myoob() later.
2148 				 */
2149 				byte_count += cnt;
2150 				offset += cnt;
2151 				filesize -= cnt;
2152 				CHECKOOB(return (-1))
2153 				else if (err == -1) {
2154 					if (errno != EINTR &&
2155 					    cnt == 0 && offset == 0)
2156 						goto oldway;
2157 					goto data_err;
2158 				}
2159 				if (err == -1)	/* resume after OOB */
2160 					continue;
2161 				/*
2162 				 * We hit the EOF prematurely.
2163 				 * Perhaps the file was externally truncated.
2164 				 */
2165 				if (cnt == 0) {
2166 					msg = "Transfer finished due to "
2167 					      "premature end of file.";
2168 					break;
2169 				}
2170 			}
2171 			ENDXFER;
2172 			reply(226, "%s", msg);
2173 			return (0);
2174 		}
2175 
2176 oldway:
2177 		if ((buf = malloc(blksize)) == NULL) {
2178 			ENDXFER;
2179 			reply(451, "Ran out of memory.");
2180 			return (-1);
2181 		}
2182 
2183 		for (;;) {
2184 			int cnt, len;
2185 			char *bp;
2186 
2187 			cnt = read(filefd, buf, blksize);
2188 			CHECKOOB(free(buf); return (-1))
2189 			else if (cnt < 0) {
2190 				free(buf);
2191 				goto file_err;
2192 			}
2193 			if (cnt < 0)	/* resume after OOB */
2194 				continue;
2195 			if (cnt == 0)	/* EOF */
2196 				break;
2197 			for (len = cnt, bp = buf; len > 0;) {
2198 				cnt = write(netfd, bp, len);
2199 				CHECKOOB(free(buf); return (-1))
2200 				else if (cnt < 0) {
2201 					free(buf);
2202 					goto data_err;
2203 				}
2204 				if (cnt <= 0)
2205 					continue;
2206 				len -= cnt;
2207 				bp += cnt;
2208 				byte_count += cnt;
2209 			}
2210 		}
2211 		ENDXFER;
2212 		free(buf);
2213 		reply(226, "Transfer complete.");
2214 		return (0);
2215 	default:
2216 		ENDXFER;
2217 		reply(550, "Unimplemented TYPE %d in send_data.", type);
2218 		return (-1);
2219 	}
2220 
2221 data_err:
2222 	ENDXFER;
2223 	perror_reply(426, "Data connection");
2224 	return (-1);
2225 
2226 file_err:
2227 	ENDXFER;
2228 	perror_reply(551, "Error on input file");
2229 	return (-1);
2230 }
2231 
2232 /*
2233  * Transfer data from peer to "outstr" using the appropriate encapulation of
2234  * the data subject to Mode, Structure, and Type.
2235  *
2236  * N.B.: Form isn't handled.
2237  */
2238 static int
2239 receive_data(FILE *instr, FILE *outstr)
2240 {
2241 	int c, cp;
2242 	int bare_lfs = 0;
2243 
2244 	STARTXFER;
2245 
2246 	switch (type) {
2247 
2248 	case TYPE_I:
2249 	case TYPE_L:
2250 		for (;;) {
2251 			int cnt, len;
2252 			char *bp;
2253 			char buf[BUFSIZ];
2254 
2255 			cnt = read(fileno(instr), buf, sizeof(buf));
2256 			CHECKOOB(return (-1))
2257 			else if (cnt < 0)
2258 				goto data_err;
2259 			if (cnt < 0)	/* resume after OOB */
2260 				continue;
2261 			if (cnt == 0)	/* EOF */
2262 				break;
2263 			for (len = cnt, bp = buf; len > 0;) {
2264 				cnt = write(fileno(outstr), bp, len);
2265 				CHECKOOB(return (-1))
2266 				else if (cnt < 0)
2267 					goto file_err;
2268 				if (cnt <= 0)
2269 					continue;
2270 				len -= cnt;
2271 				bp += cnt;
2272 				byte_count += cnt;
2273 			}
2274 		}
2275 		ENDXFER;
2276 		return (0);
2277 
2278 	case TYPE_E:
2279 		ENDXFER;
2280 		reply(553, "TYPE E not implemented.");
2281 		return (-1);
2282 
2283 	case TYPE_A:
2284 		cp = EOF;
2285 		for (;;) {
2286 			c = getc(instr);
2287 			CHECKOOB(return (-1))
2288 			else if (c == EOF && ferror(instr))
2289 				goto data_err;
2290 			if (c == EOF && ferror(instr)) { /* resume after OOB */
2291 				clearerr(instr);
2292 				continue;
2293 			}
2294 
2295 			if (cp == '\r') {
2296 				if (c != '\n')
2297 					FTPD_PUTC('\r', outstr, file_err);
2298 			} else
2299 				if (c == '\n')
2300 					bare_lfs++;
2301 			if (c == '\r') {
2302 				byte_count++;
2303 				cp = c;
2304 				continue;
2305 			}
2306 
2307 			/* Check for EOF here in order not to lose last \r. */
2308 			if (c == EOF) {
2309 				if (feof(instr))	/* EOF */
2310 					break;
2311 				syslog(LOG_ERR, "Internal: impossible condition"
2312 						" on data stream after getc()");
2313 				goto data_err;
2314 			}
2315 
2316 			byte_count++;
2317 			FTPD_PUTC(c, outstr, file_err);
2318 			cp = c;
2319 		}
2320 #ifdef notyet	/* BSD stdio isn't ready for that */
2321 		while (fflush(outstr) == EOF) {
2322 			CHECKOOB(return (-1))
2323 			else
2324 				goto file_err;
2325 			clearerr(outstr);
2326 		}
2327 		ENDXFER;
2328 #else
2329 		ENDXFER;
2330 		if (fflush(outstr) == EOF)
2331 			goto file_err;
2332 #endif
2333 		if (bare_lfs) {
2334 			lreply(226,
2335 		"WARNING! %d bare linefeeds received in ASCII mode.",
2336 			    bare_lfs);
2337 		(void)printf("   File may not have transferred correctly.\r\n");
2338 		}
2339 		return (0);
2340 	default:
2341 		ENDXFER;
2342 		reply(550, "Unimplemented TYPE %d in receive_data.", type);
2343 		return (-1);
2344 	}
2345 
2346 data_err:
2347 	ENDXFER;
2348 	perror_reply(426, "Data connection");
2349 	return (-1);
2350 
2351 file_err:
2352 	ENDXFER;
2353 	perror_reply(452, "Error writing to file");
2354 	return (-1);
2355 }
2356 
2357 void
2358 statfilecmd(char *filename)
2359 {
2360 	FILE *fin;
2361 	int atstart;
2362 	int c, code;
2363 	char line[LINE_MAX];
2364 	struct stat st;
2365 
2366 	code = lstat(filename, &st) == 0 && S_ISDIR(st.st_mode) ? 212 : 213;
2367 	(void)snprintf(line, sizeof(line), _PATH_LS " -lgA %s", filename);
2368 	fin = ftpd_popen(line, "r");
2369 	if (fin == NULL) {
2370 		perror_reply(551, filename);
2371 		return;
2372 	}
2373 	lreply(code, "Status of %s:", filename);
2374 	atstart = 1;
2375 	while ((c = getc(fin)) != EOF) {
2376 		if (c == '\n') {
2377 			if (ferror(stdout)){
2378 				perror_reply(421, "Control connection");
2379 				(void) ftpd_pclose(fin);
2380 				dologout(1);
2381 				/* NOTREACHED */
2382 			}
2383 			if (ferror(fin)) {
2384 				perror_reply(551, filename);
2385 				(void) ftpd_pclose(fin);
2386 				return;
2387 			}
2388 			(void) putc('\r', stdout);
2389 		}
2390 		/*
2391 		 * RFC 959 says neutral text should be prepended before
2392 		 * a leading 3-digit number followed by whitespace, but
2393 		 * many ftp clients can be confused by any leading digits,
2394 		 * as a matter of fact.
2395 		 */
2396 		if (atstart && isdigit(c))
2397 			(void) putc(' ', stdout);
2398 		(void) putc(c, stdout);
2399 		atstart = (c == '\n');
2400 	}
2401 	(void) ftpd_pclose(fin);
2402 	reply(code, "End of status.");
2403 }
2404 
2405 void
2406 statcmd(void)
2407 {
2408 	union sockunion *su;
2409 	u_char *a, *p;
2410 	char hname[NI_MAXHOST];
2411 	int ispassive;
2412 
2413 	if (hostinfo) {
2414 		lreply(211, "%s FTP server status:", hostname);
2415 		printf("     %s\r\n", version);
2416 	} else
2417 		lreply(211, "FTP server status:");
2418 	printf("     Connected to %s", remotehost);
2419 	if (!getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
2420 			 hname, sizeof(hname) - 1, NULL, 0, NI_NUMERICHOST)) {
2421 		hname[sizeof(hname) - 1] = 0;
2422 		if (strcmp(hname, remotehost) != 0)
2423 			printf(" (%s)", hname);
2424 	}
2425 	printf("\r\n");
2426 	if (logged_in) {
2427 		if (guest)
2428 			printf("     Logged in anonymously\r\n");
2429 		else
2430 			printf("     Logged in as %s\r\n", pw->pw_name);
2431 	} else if (askpasswd)
2432 		printf("     Waiting for password\r\n");
2433 	else
2434 		printf("     Waiting for user name\r\n");
2435 	printf("     TYPE: %s", typenames[type]);
2436 	if (type == TYPE_A || type == TYPE_E)
2437 		printf(", FORM: %s", formnames[form]);
2438 	if (type == TYPE_L)
2439 #if CHAR_BIT == 8
2440 		printf(" %d", CHAR_BIT);
2441 #else
2442 		printf(" %d", bytesize);	/* need definition! */
2443 #endif
2444 	printf("; STRUcture: %s; transfer MODE: %s\r\n",
2445 	    strunames[stru], modenames[mode]);
2446 	if (data != -1)
2447 		printf("     Data connection open\r\n");
2448 	else if (pdata != -1) {
2449 		ispassive = 1;
2450 		su = &pasv_addr;
2451 		goto printaddr;
2452 	} else if (usedefault == 0) {
2453 		ispassive = 0;
2454 		su = &data_dest;
2455 printaddr:
2456 #define UC(b) (((int) b) & 0xff)
2457 		if (epsvall) {
2458 			printf("     EPSV only mode (EPSV ALL)\r\n");
2459 			goto epsvonly;
2460 		}
2461 
2462 		/* PORT/PASV */
2463 		if (su->su_family == AF_INET) {
2464 			a = (u_char *) &su->su_sin.sin_addr;
2465 			p = (u_char *) &su->su_sin.sin_port;
2466 			printf("     %s (%d,%d,%d,%d,%d,%d)\r\n",
2467 				ispassive ? "PASV" : "PORT",
2468 				UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
2469 				UC(p[0]), UC(p[1]));
2470 		}
2471 
2472 		/* LPRT/LPSV */
2473 	    {
2474 		int alen, af, i;
2475 
2476 		switch (su->su_family) {
2477 		case AF_INET:
2478 			a = (u_char *) &su->su_sin.sin_addr;
2479 			p = (u_char *) &su->su_sin.sin_port;
2480 			alen = sizeof(su->su_sin.sin_addr);
2481 			af = 4;
2482 			break;
2483 		case AF_INET6:
2484 			a = (u_char *) &su->su_sin6.sin6_addr;
2485 			p = (u_char *) &su->su_sin6.sin6_port;
2486 			alen = sizeof(su->su_sin6.sin6_addr);
2487 			af = 6;
2488 			break;
2489 		default:
2490 			af = 0;
2491 			break;
2492 		}
2493 		if (af) {
2494 			printf("     %s (%d,%d,", ispassive ? "LPSV" : "LPRT",
2495 				af, alen);
2496 			for (i = 0; i < alen; i++)
2497 				printf("%d,", UC(a[i]));
2498 			printf("%d,%d,%d)\r\n", 2, UC(p[0]), UC(p[1]));
2499 		}
2500 	    }
2501 
2502 epsvonly:;
2503 		/* EPRT/EPSV */
2504 	    {
2505 		int af;
2506 
2507 		switch (su->su_family) {
2508 		case AF_INET:
2509 			af = 1;
2510 			break;
2511 		case AF_INET6:
2512 			af = 2;
2513 			break;
2514 		default:
2515 			af = 0;
2516 			break;
2517 		}
2518 		if (af) {
2519 			union sockunion tmp;
2520 
2521 			tmp = *su;
2522 			if (tmp.su_family == AF_INET6)
2523 				tmp.su_sin6.sin6_scope_id = 0;
2524 			if (!getnameinfo((struct sockaddr *)&tmp, tmp.su_len,
2525 					hname, sizeof(hname) - 1, NULL, 0,
2526 					NI_NUMERICHOST)) {
2527 				hname[sizeof(hname) - 1] = 0;
2528 				printf("     %s |%d|%s|%d|\r\n",
2529 					ispassive ? "EPSV" : "EPRT",
2530 					af, hname, htons(tmp.su_port));
2531 			}
2532 		}
2533 	    }
2534 #undef UC
2535 	} else
2536 		printf("     No data connection\r\n");
2537 	reply(211, "End of status.");
2538 }
2539 
2540 void
2541 fatalerror(char *s)
2542 {
2543 
2544 	reply(451, "Error in server: %s", s);
2545 	reply(221, "Closing connection due to server error.");
2546 	dologout(0);
2547 	/* NOTREACHED */
2548 }
2549 
2550 void
2551 reply(int n, const char *fmt, ...)
2552 {
2553 	va_list ap;
2554 
2555 	(void)printf("%d ", n);
2556 	va_start(ap, fmt);
2557 	(void)vprintf(fmt, ap);
2558 	va_end(ap);
2559 	(void)printf("\r\n");
2560 	(void)fflush(stdout);
2561 	if (ftpdebug) {
2562 		syslog(LOG_DEBUG, "<--- %d ", n);
2563 		va_start(ap, fmt);
2564 		vsyslog(LOG_DEBUG, fmt, ap);
2565 		va_end(ap);
2566 	}
2567 }
2568 
2569 void
2570 lreply(int n, const char *fmt, ...)
2571 {
2572 	va_list ap;
2573 
2574 	(void)printf("%d- ", n);
2575 	va_start(ap, fmt);
2576 	(void)vprintf(fmt, ap);
2577 	va_end(ap);
2578 	(void)printf("\r\n");
2579 	(void)fflush(stdout);
2580 	if (ftpdebug) {
2581 		syslog(LOG_DEBUG, "<--- %d- ", n);
2582 		va_start(ap, fmt);
2583 		vsyslog(LOG_DEBUG, fmt, ap);
2584 		va_end(ap);
2585 	}
2586 }
2587 
2588 static void
2589 ack(char *s)
2590 {
2591 
2592 	reply(250, "%s command successful.", s);
2593 }
2594 
2595 void
2596 nack(char *s)
2597 {
2598 
2599 	reply(502, "%s command not implemented.", s);
2600 }
2601 
2602 /* ARGSUSED */
2603 void
2604 yyerror(char *s)
2605 {
2606 	char *cp;
2607 
2608 	if ((cp = strchr(cbuf,'\n')))
2609 		*cp = '\0';
2610 	reply(500, "%s: command not understood.", cbuf);
2611 }
2612 
2613 void
2614 delete(char *name)
2615 {
2616 	struct stat st;
2617 
2618 	LOGCMD("delete", name);
2619 	if (lstat(name, &st) < 0) {
2620 		perror_reply(550, name);
2621 		return;
2622 	}
2623 	if (S_ISDIR(st.st_mode)) {
2624 		if (rmdir(name) < 0) {
2625 			perror_reply(550, name);
2626 			return;
2627 		}
2628 		goto done;
2629 	}
2630 	if (guest && noguestmod) {
2631 		reply(550, "Operation not permitted.");
2632 		return;
2633 	}
2634 	if (unlink(name) < 0) {
2635 		perror_reply(550, name);
2636 		return;
2637 	}
2638 done:
2639 	ack("DELE");
2640 }
2641 
2642 void
2643 cwd(char *path)
2644 {
2645 
2646 	if (chdir(path) < 0)
2647 		perror_reply(550, path);
2648 	else
2649 		ack("CWD");
2650 }
2651 
2652 void
2653 makedir(char *name)
2654 {
2655 	char *s;
2656 
2657 	LOGCMD("mkdir", name);
2658 	if (guest && noguestmkd)
2659 		reply(550, "Operation not permitted.");
2660 	else if (mkdir(name, 0777) < 0)
2661 		perror_reply(550, name);
2662 	else {
2663 		if ((s = doublequote(name)) == NULL)
2664 			fatalerror("Ran out of memory.");
2665 		reply(257, "\"%s\" directory created.", s);
2666 		free(s);
2667 	}
2668 }
2669 
2670 void
2671 removedir(char *name)
2672 {
2673 
2674 	LOGCMD("rmdir", name);
2675 	if (rmdir(name) < 0)
2676 		perror_reply(550, name);
2677 	else
2678 		ack("RMD");
2679 }
2680 
2681 void
2682 pwd(void)
2683 {
2684 	char *s, path[MAXPATHLEN + 1];
2685 
2686 	if (getcwd(path, sizeof(path)) == NULL)
2687 		perror_reply(550, "Get current directory");
2688 	else {
2689 		if ((s = doublequote(path)) == NULL)
2690 			fatalerror("Ran out of memory.");
2691 		reply(257, "\"%s\" is current directory.", s);
2692 		free(s);
2693 	}
2694 }
2695 
2696 char *
2697 renamefrom(char *name)
2698 {
2699 	struct stat st;
2700 
2701 	if (guest && noguestmod) {
2702 		reply(550, "Operation not permitted.");
2703 		return (NULL);
2704 	}
2705 	if (lstat(name, &st) < 0) {
2706 		perror_reply(550, name);
2707 		return (NULL);
2708 	}
2709 	reply(350, "File exists, ready for destination name.");
2710 	return (name);
2711 }
2712 
2713 void
2714 renamecmd(char *from, char *to)
2715 {
2716 	struct stat st;
2717 
2718 	LOGCMD2("rename", from, to);
2719 
2720 	if (guest && (stat(to, &st) == 0)) {
2721 		reply(550, "%s: permission denied.", to);
2722 		return;
2723 	}
2724 
2725 	if (rename(from, to) < 0)
2726 		perror_reply(550, "rename");
2727 	else
2728 		ack("RNTO");
2729 }
2730 
2731 static void
2732 dolog(struct sockaddr *who)
2733 {
2734 	char who_name[NI_MAXHOST];
2735 
2736 	realhostname_sa(remotehost, sizeof(remotehost) - 1, who, who->sa_len);
2737 	remotehost[sizeof(remotehost) - 1] = 0;
2738 	if (getnameinfo(who, who->sa_len,
2739 		who_name, sizeof(who_name) - 1, NULL, 0, NI_NUMERICHOST))
2740 			*who_name = 0;
2741 	who_name[sizeof(who_name) - 1] = 0;
2742 
2743 #ifdef SETPROCTITLE
2744 #ifdef VIRTUAL_HOSTING
2745 	if (thishost != firsthost)
2746 		snprintf(proctitle, sizeof(proctitle), "%s: connected (to %s)",
2747 			 remotehost, hostname);
2748 	else
2749 #endif
2750 		snprintf(proctitle, sizeof(proctitle), "%s: connected",
2751 			 remotehost);
2752 	setproctitle("%s", proctitle);
2753 #endif /* SETPROCTITLE */
2754 
2755 	if (logging) {
2756 #ifdef VIRTUAL_HOSTING
2757 		if (thishost != firsthost)
2758 			syslog(LOG_INFO, "connection from %s (%s) to %s",
2759 			       remotehost, who_name, hostname);
2760 		else
2761 #endif
2762 			syslog(LOG_INFO, "connection from %s (%s)",
2763 			       remotehost, who_name);
2764 	}
2765 }
2766 
2767 /*
2768  * Record logout in wtmp file
2769  * and exit with supplied status.
2770  */
2771 void
2772 dologout(int status)
2773 {
2774 
2775 	if (logged_in && dowtmp) {
2776 		(void) seteuid(0);
2777 #ifdef		LOGIN_CAP
2778  	        setusercontext(NULL, getpwuid(0), 0, LOGIN_SETALL & ~(LOGIN_SETLOGIN |
2779 		       LOGIN_SETUSER | LOGIN_SETGROUP | LOGIN_SETPATH |
2780 		       LOGIN_SETENV));
2781 #endif
2782 		ftpd_logwtmp(wtmpid, NULL, NULL);
2783 	}
2784 	/* beware of flushing buffers after a SIGPIPE */
2785 	_exit(status);
2786 }
2787 
2788 static void
2789 sigurg(int signo)
2790 {
2791 
2792 	recvurg = 1;
2793 }
2794 
2795 static void
2796 maskurg(int flag)
2797 {
2798 	int oerrno;
2799 	sigset_t sset;
2800 
2801 	if (!transflag) {
2802 		syslog(LOG_ERR, "Internal: maskurg() while no transfer");
2803 		return;
2804 	}
2805 	oerrno = errno;
2806 	sigemptyset(&sset);
2807 	sigaddset(&sset, SIGURG);
2808 	sigprocmask(flag ? SIG_BLOCK : SIG_UNBLOCK, &sset, NULL);
2809 	errno = oerrno;
2810 }
2811 
2812 static void
2813 flagxfer(int flag)
2814 {
2815 
2816 	if (flag) {
2817 		if (transflag)
2818 			syslog(LOG_ERR, "Internal: flagxfer(1): "
2819 					"transfer already under way");
2820 		transflag = 1;
2821 		maskurg(0);
2822 		recvurg = 0;
2823 	} else {
2824 		if (!transflag)
2825 			syslog(LOG_ERR, "Internal: flagxfer(0): "
2826 					"no active transfer");
2827 		maskurg(1);
2828 		transflag = 0;
2829 	}
2830 }
2831 
2832 /*
2833  * Returns 0 if OK to resume or -1 if abort requested.
2834  */
2835 static int
2836 myoob(void)
2837 {
2838 	char *cp;
2839 	int ret;
2840 
2841 	if (!transflag) {
2842 		syslog(LOG_ERR, "Internal: myoob() while no transfer");
2843 		return (0);
2844 	}
2845 	cp = tmpline;
2846 	ret = get_line(cp, 7, stdin);
2847 	if (ret == -1) {
2848 		reply(221, "You could at least say goodbye.");
2849 		dologout(0);
2850 	} else if (ret == -2) {
2851 		/* Ignore truncated command. */
2852 		return (0);
2853 	}
2854 	upper(cp);
2855 	if (strcmp(cp, "ABOR\r\n") == 0) {
2856 		tmpline[0] = '\0';
2857 		reply(426, "Transfer aborted. Data connection closed.");
2858 		reply(226, "Abort successful.");
2859 		return (-1);
2860 	}
2861 	if (strcmp(cp, "STAT\r\n") == 0) {
2862 		tmpline[0] = '\0';
2863 		if (file_size != -1)
2864 			reply(213, "Status: %jd of %jd bytes transferred.",
2865 				   (intmax_t)byte_count, (intmax_t)file_size);
2866 		else
2867 			reply(213, "Status: %jd bytes transferred.",
2868 				   (intmax_t)byte_count);
2869 	}
2870 	return (0);
2871 }
2872 
2873 /*
2874  * Note: a response of 425 is not mentioned as a possible response to
2875  *	the PASV command in RFC959. However, it has been blessed as
2876  *	a legitimate response by Jon Postel in a telephone conversation
2877  *	with Rick Adams on 25 Jan 89.
2878  */
2879 void
2880 passive(void)
2881 {
2882 	socklen_t len;
2883 	int on;
2884 	char *p, *a;
2885 
2886 	if (pdata >= 0)		/* close old port if one set */
2887 		close(pdata);
2888 
2889 	pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
2890 	if (pdata < 0) {
2891 		perror_reply(425, "Can't open passive connection");
2892 		return;
2893 	}
2894 	on = 1;
2895 	if (setsockopt(pdata, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
2896 		syslog(LOG_WARNING, "pdata setsockopt (SO_REUSEADDR): %m");
2897 
2898 	(void) seteuid(0);
2899 
2900 #ifdef IP_PORTRANGE
2901 	if (ctrl_addr.su_family == AF_INET) {
2902 	    on = restricted_data_ports ? IP_PORTRANGE_HIGH
2903 				       : IP_PORTRANGE_DEFAULT;
2904 
2905 	    if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE,
2906 			    &on, sizeof(on)) < 0)
2907 		    goto pasv_error;
2908 	}
2909 #endif
2910 #ifdef IPV6_PORTRANGE
2911 	if (ctrl_addr.su_family == AF_INET6) {
2912 	    on = restricted_data_ports ? IPV6_PORTRANGE_HIGH
2913 				       : IPV6_PORTRANGE_DEFAULT;
2914 
2915 	    if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE,
2916 			    &on, sizeof(on)) < 0)
2917 		    goto pasv_error;
2918 	}
2919 #endif
2920 
2921 	pasv_addr = ctrl_addr;
2922 	pasv_addr.su_port = 0;
2923 	if (bind(pdata, (struct sockaddr *)&pasv_addr, pasv_addr.su_len) < 0)
2924 		goto pasv_error;
2925 
2926 	(void) seteuid(pw->pw_uid);
2927 
2928 	len = sizeof(pasv_addr);
2929 	if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0)
2930 		goto pasv_error;
2931 	if (listen(pdata, 1) < 0)
2932 		goto pasv_error;
2933 	if (pasv_addr.su_family == AF_INET)
2934 		a = (char *) &pasv_addr.su_sin.sin_addr;
2935 	else if (pasv_addr.su_family == AF_INET6 &&
2936 		 IN6_IS_ADDR_V4MAPPED(&pasv_addr.su_sin6.sin6_addr))
2937 		a = (char *) &pasv_addr.su_sin6.sin6_addr.s6_addr[12];
2938 	else
2939 		goto pasv_error;
2940 
2941 	p = (char *) &pasv_addr.su_port;
2942 
2943 #define UC(b) (((int) b) & 0xff)
2944 
2945 	reply(227, "Entering Passive Mode (%d,%d,%d,%d,%d,%d)", UC(a[0]),
2946 		UC(a[1]), UC(a[2]), UC(a[3]), UC(p[0]), UC(p[1]));
2947 	return;
2948 
2949 pasv_error:
2950 	(void) seteuid(pw->pw_uid);
2951 	(void) close(pdata);
2952 	pdata = -1;
2953 	perror_reply(425, "Can't open passive connection");
2954 	return;
2955 }
2956 
2957 /*
2958  * Long Passive defined in RFC 1639.
2959  *     228 Entering Long Passive Mode
2960  *         (af, hal, h1, h2, h3,..., pal, p1, p2...)
2961  */
2962 
2963 void
2964 long_passive(char *cmd, int pf)
2965 {
2966 	socklen_t len;
2967 	int on;
2968 	char *p, *a;
2969 
2970 	if (pdata >= 0)		/* close old port if one set */
2971 		close(pdata);
2972 
2973 	if (pf != PF_UNSPEC) {
2974 		if (ctrl_addr.su_family != pf) {
2975 			switch (ctrl_addr.su_family) {
2976 			case AF_INET:
2977 				pf = 1;
2978 				break;
2979 			case AF_INET6:
2980 				pf = 2;
2981 				break;
2982 			default:
2983 				pf = 0;
2984 				break;
2985 			}
2986 			/*
2987 			 * XXX
2988 			 * only EPRT/EPSV ready clients will understand this
2989 			 */
2990 			if (strcmp(cmd, "EPSV") == 0 && pf) {
2991 				reply(522, "Network protocol mismatch, "
2992 					"use (%d)", pf);
2993 			} else
2994 				reply(501, "Network protocol mismatch."); /*XXX*/
2995 
2996 			return;
2997 		}
2998 	}
2999 
3000 	pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
3001 	if (pdata < 0) {
3002 		perror_reply(425, "Can't open passive connection");
3003 		return;
3004 	}
3005 	on = 1;
3006 	if (setsockopt(pdata, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
3007 		syslog(LOG_WARNING, "pdata setsockopt (SO_REUSEADDR): %m");
3008 
3009 	(void) seteuid(0);
3010 
3011 	pasv_addr = ctrl_addr;
3012 	pasv_addr.su_port = 0;
3013 	len = pasv_addr.su_len;
3014 
3015 #ifdef IP_PORTRANGE
3016 	if (ctrl_addr.su_family == AF_INET) {
3017 	    on = restricted_data_ports ? IP_PORTRANGE_HIGH
3018 				       : IP_PORTRANGE_DEFAULT;
3019 
3020 	    if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE,
3021 			    &on, sizeof(on)) < 0)
3022 		    goto pasv_error;
3023 	}
3024 #endif
3025 #ifdef IPV6_PORTRANGE
3026 	if (ctrl_addr.su_family == AF_INET6) {
3027 	    on = restricted_data_ports ? IPV6_PORTRANGE_HIGH
3028 				       : IPV6_PORTRANGE_DEFAULT;
3029 
3030 	    if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE,
3031 			    &on, sizeof(on)) < 0)
3032 		    goto pasv_error;
3033 	}
3034 #endif
3035 
3036 	if (bind(pdata, (struct sockaddr *)&pasv_addr, len) < 0)
3037 		goto pasv_error;
3038 
3039 	(void) seteuid(pw->pw_uid);
3040 
3041 	if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0)
3042 		goto pasv_error;
3043 	if (listen(pdata, 1) < 0)
3044 		goto pasv_error;
3045 
3046 #define UC(b) (((int) b) & 0xff)
3047 
3048 	if (strcmp(cmd, "LPSV") == 0) {
3049 		p = (char *)&pasv_addr.su_port;
3050 		switch (pasv_addr.su_family) {
3051 		case AF_INET:
3052 			a = (char *) &pasv_addr.su_sin.sin_addr;
3053 		v4_reply:
3054 			reply(228,
3055 "Entering Long Passive Mode (%d,%d,%d,%d,%d,%d,%d,%d,%d)",
3056 			      4, 4, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
3057 			      2, UC(p[0]), UC(p[1]));
3058 			return;
3059 		case AF_INET6:
3060 			if (IN6_IS_ADDR_V4MAPPED(&pasv_addr.su_sin6.sin6_addr)) {
3061 				a = (char *) &pasv_addr.su_sin6.sin6_addr.s6_addr[12];
3062 				goto v4_reply;
3063 			}
3064 			a = (char *) &pasv_addr.su_sin6.sin6_addr;
3065 			reply(228,
3066 "Entering Long Passive Mode "
3067 "(%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d)",
3068 			      6, 16, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
3069 			      UC(a[4]), UC(a[5]), UC(a[6]), UC(a[7]),
3070 			      UC(a[8]), UC(a[9]), UC(a[10]), UC(a[11]),
3071 			      UC(a[12]), UC(a[13]), UC(a[14]), UC(a[15]),
3072 			      2, UC(p[0]), UC(p[1]));
3073 			return;
3074 		}
3075 	} else if (strcmp(cmd, "EPSV") == 0) {
3076 		switch (pasv_addr.su_family) {
3077 		case AF_INET:
3078 		case AF_INET6:
3079 			reply(229, "Entering Extended Passive Mode (|||%d|)",
3080 				ntohs(pasv_addr.su_port));
3081 			return;
3082 		}
3083 	} else {
3084 		/* more proper error code? */
3085 	}
3086 
3087 pasv_error:
3088 	(void) seteuid(pw->pw_uid);
3089 	(void) close(pdata);
3090 	pdata = -1;
3091 	perror_reply(425, "Can't open passive connection");
3092 	return;
3093 }
3094 
3095 /*
3096  * Generate unique name for file with basename "local"
3097  * and open the file in order to avoid possible races.
3098  * Try "local" first, then "local.1", "local.2" etc, up to "local.99".
3099  * Return descriptor to the file, set "name" to its name.
3100  *
3101  * Generates failure reply on error.
3102  */
3103 static int
3104 guniquefd(char *local, char **name)
3105 {
3106 	static char new[MAXPATHLEN];
3107 	struct stat st;
3108 	char *cp;
3109 	int count;
3110 	int fd;
3111 
3112 	cp = strrchr(local, '/');
3113 	if (cp)
3114 		*cp = '\0';
3115 	if (stat(cp ? local : ".", &st) < 0) {
3116 		perror_reply(553, cp ? local : ".");
3117 		return (-1);
3118 	}
3119 	if (cp) {
3120 		/*
3121 		 * Let not overwrite dirname with counter suffix.
3122 		 * -4 is for /nn\0
3123 		 * In this extreme case dot won't be put in front of suffix.
3124 		 */
3125 		if (strlen(local) > sizeof(new) - 4) {
3126 			reply(553, "Pathname too long.");
3127 			return (-1);
3128 		}
3129 		*cp = '/';
3130 	}
3131 	/* -4 is for the .nn<null> we put on the end below */
3132 	(void) snprintf(new, sizeof(new) - 4, "%s", local);
3133 	cp = new + strlen(new);
3134 	/*
3135 	 * Don't generate dotfile unless requested explicitly.
3136 	 * This covers the case when basename gets truncated off
3137 	 * by buffer size.
3138 	 */
3139 	if (cp > new && cp[-1] != '/')
3140 		*cp++ = '.';
3141 	for (count = 0; count < 100; count++) {
3142 		/* At count 0 try unmodified name */
3143 		if (count)
3144 			(void)sprintf(cp, "%d", count);
3145 		if ((fd = open(count ? new : local,
3146 		    O_RDWR | O_CREAT | O_EXCL, 0666)) >= 0) {
3147 			*name = count ? new : local;
3148 			return (fd);
3149 		}
3150 		if (errno != EEXIST) {
3151 			perror_reply(553, count ? new : local);
3152 			return (-1);
3153 		}
3154 	}
3155 	reply(452, "Unique file name cannot be created.");
3156 	return (-1);
3157 }
3158 
3159 /*
3160  * Format and send reply containing system error number.
3161  */
3162 void
3163 perror_reply(int code, char *string)
3164 {
3165 
3166 	reply(code, "%s: %s.", string, strerror(errno));
3167 }
3168 
3169 static char *onefile[] = {
3170 	"",
3171 	0
3172 };
3173 
3174 void
3175 send_file_list(char *whichf)
3176 {
3177 	struct stat st;
3178 	DIR *dirp = NULL;
3179 	struct dirent *dir;
3180 	FILE *dout = NULL;
3181 	char **dirlist, *dirname;
3182 	int simple = 0;
3183 	int freeglob = 0;
3184 	glob_t gl;
3185 
3186 	if (strpbrk(whichf, "~{[*?") != NULL) {
3187 		int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE;
3188 
3189 		memset(&gl, 0, sizeof(gl));
3190 		gl.gl_matchc = MAXGLOBARGS;
3191 		flags |= GLOB_LIMIT;
3192 		freeglob = 1;
3193 		if (glob(whichf, flags, 0, &gl)) {
3194 			reply(550, "No matching files found.");
3195 			goto out;
3196 		} else if (gl.gl_pathc == 0) {
3197 			errno = ENOENT;
3198 			perror_reply(550, whichf);
3199 			goto out;
3200 		}
3201 		dirlist = gl.gl_pathv;
3202 	} else {
3203 		onefile[0] = whichf;
3204 		dirlist = onefile;
3205 		simple = 1;
3206 	}
3207 
3208 	while ((dirname = *dirlist++)) {
3209 		if (stat(dirname, &st) < 0) {
3210 			/*
3211 			 * If user typed "ls -l", etc, and the client
3212 			 * used NLST, do what the user meant.
3213 			 */
3214 			if (dirname[0] == '-' && *dirlist == NULL &&
3215 			    dout == NULL)
3216 				retrieve(_PATH_LS " %s", dirname);
3217 			else
3218 				perror_reply(550, whichf);
3219 			goto out;
3220 		}
3221 
3222 		if (S_ISREG(st.st_mode)) {
3223 			if (dout == NULL) {
3224 				dout = dataconn("file list", -1, "w");
3225 				if (dout == NULL)
3226 					goto out;
3227 				STARTXFER;
3228 			}
3229 			START_UNSAFE;
3230 			fprintf(dout, "%s%s\n", dirname,
3231 				type == TYPE_A ? "\r" : "");
3232 			END_UNSAFE;
3233 			if (ferror(dout))
3234 				goto data_err;
3235 			byte_count += strlen(dirname) +
3236 				      (type == TYPE_A ? 2 : 1);
3237 			CHECKOOB(goto abrt);
3238 			continue;
3239 		} else if (!S_ISDIR(st.st_mode))
3240 			continue;
3241 
3242 		if ((dirp = opendir(dirname)) == NULL)
3243 			continue;
3244 
3245 		while ((dir = readdir(dirp)) != NULL) {
3246 			char nbuf[MAXPATHLEN];
3247 
3248 			CHECKOOB(goto abrt);
3249 
3250 			if (dir->d_name[0] == '.' && dir->d_namlen == 1)
3251 				continue;
3252 			if (dir->d_name[0] == '.' && dir->d_name[1] == '.' &&
3253 			    dir->d_namlen == 2)
3254 				continue;
3255 
3256 			snprintf(nbuf, sizeof(nbuf),
3257 				"%s/%s", dirname, dir->d_name);
3258 
3259 			/*
3260 			 * We have to do a stat to insure it's
3261 			 * not a directory or special file.
3262 			 */
3263 			if (simple || (stat(nbuf, &st) == 0 &&
3264 			    S_ISREG(st.st_mode))) {
3265 				if (dout == NULL) {
3266 					dout = dataconn("file list", -1, "w");
3267 					if (dout == NULL)
3268 						goto out;
3269 					STARTXFER;
3270 				}
3271 				START_UNSAFE;
3272 				if (nbuf[0] == '.' && nbuf[1] == '/')
3273 					fprintf(dout, "%s%s\n", &nbuf[2],
3274 						type == TYPE_A ? "\r" : "");
3275 				else
3276 					fprintf(dout, "%s%s\n", nbuf,
3277 						type == TYPE_A ? "\r" : "");
3278 				END_UNSAFE;
3279 				if (ferror(dout))
3280 					goto data_err;
3281 				byte_count += strlen(nbuf) +
3282 					      (type == TYPE_A ? 2 : 1);
3283 				CHECKOOB(goto abrt);
3284 			}
3285 		}
3286 		(void) closedir(dirp);
3287 		dirp = NULL;
3288 	}
3289 
3290 	if (dout == NULL)
3291 		reply(550, "No files found.");
3292 	else if (ferror(dout))
3293 data_err:	perror_reply(550, "Data connection");
3294 	else
3295 		reply(226, "Transfer complete.");
3296 out:
3297 	if (dout) {
3298 		ENDXFER;
3299 abrt:
3300 		(void) fclose(dout);
3301 		data = -1;
3302 		pdata = -1;
3303 	}
3304 	if (dirp)
3305 		(void) closedir(dirp);
3306 	if (freeglob) {
3307 		freeglob = 0;
3308 		globfree(&gl);
3309 	}
3310 }
3311 
3312 void
3313 reapchild(int signo)
3314 {
3315 	while (waitpid(-1, NULL, WNOHANG) > 0);
3316 }
3317 
3318 static void
3319 appendf(char **strp, char *fmt, ...)
3320 {
3321 	va_list ap;
3322 	char *ostr, *p;
3323 
3324 	va_start(ap, fmt);
3325 	vasprintf(&p, fmt, ap);
3326 	va_end(ap);
3327 	if (p == NULL)
3328 		fatalerror("Ran out of memory.");
3329 	if (*strp == NULL)
3330 		*strp = p;
3331 	else {
3332 		ostr = *strp;
3333 		asprintf(strp, "%s%s", ostr, p);
3334 		if (*strp == NULL)
3335 			fatalerror("Ran out of memory.");
3336 		free(ostr);
3337 	}
3338 }
3339 
3340 static void
3341 logcmd(char *cmd, char *file1, char *file2, off_t cnt)
3342 {
3343 	char *msg = NULL;
3344 	char wd[MAXPATHLEN + 1];
3345 
3346 	if (logging <= 1)
3347 		return;
3348 
3349 	if (getcwd(wd, sizeof(wd) - 1) == NULL)
3350 		strcpy(wd, strerror(errno));
3351 
3352 	appendf(&msg, "%s", cmd);
3353 	if (file1)
3354 		appendf(&msg, " %s", file1);
3355 	if (file2)
3356 		appendf(&msg, " %s", file2);
3357 	if (cnt >= 0)
3358 		appendf(&msg, " = %jd bytes", (intmax_t)cnt);
3359 	appendf(&msg, " (wd: %s", wd);
3360 	if (guest || dochroot)
3361 		appendf(&msg, "; chrooted");
3362 	appendf(&msg, ")");
3363 	syslog(LOG_INFO, "%s", msg);
3364 	free(msg);
3365 }
3366 
3367 static void
3368 logxfer(char *name, off_t size, time_t start)
3369 {
3370 	char buf[MAXPATHLEN + 1024];
3371 	char path[MAXPATHLEN + 1];
3372 	time_t now;
3373 
3374 	if (statfd >= 0) {
3375 		time(&now);
3376 		if (realpath(name, path) == NULL) {
3377 			syslog(LOG_NOTICE, "realpath failed on %s: %m", path);
3378 			return;
3379 		}
3380 		snprintf(buf, sizeof(buf), "%.20s!%s!%s!%s!%jd!%ld\n",
3381 			ctime(&now)+4, ident, remotehost,
3382 			path, (intmax_t)size,
3383 			(long)(now - start + (now == start)));
3384 		write(statfd, buf, strlen(buf));
3385 	}
3386 }
3387 
3388 static char *
3389 doublequote(char *s)
3390 {
3391 	int n;
3392 	char *p, *s2;
3393 
3394 	for (p = s, n = 0; *p; p++)
3395 		if (*p == '"')
3396 			n++;
3397 
3398 	if ((s2 = malloc(p - s + n + 1)) == NULL)
3399 		return (NULL);
3400 
3401 	for (p = s2; *s; s++, p++) {
3402 		if ((*p = *s) == '"')
3403 			*(++p) = '"';
3404 	}
3405 	*p = '\0';
3406 
3407 	return (s2);
3408 }
3409 
3410 /* setup server socket for specified address family */
3411 /* if af is PF_UNSPEC more than one socket may be returned */
3412 /* the returned list is dynamically allocated, so caller needs to free it */
3413 static int *
3414 socksetup(int af, char *bindname, const char *bindport)
3415 {
3416 	struct addrinfo hints, *res, *r;
3417 	int error, maxs, *s, *socks;
3418 	const int on = 1;
3419 
3420 	memset(&hints, 0, sizeof(hints));
3421 	hints.ai_flags = AI_PASSIVE;
3422 	hints.ai_family = af;
3423 	hints.ai_socktype = SOCK_STREAM;
3424 	error = getaddrinfo(bindname, bindport, &hints, &res);
3425 	if (error) {
3426 		syslog(LOG_ERR, "%s", gai_strerror(error));
3427 		if (error == EAI_SYSTEM)
3428 			syslog(LOG_ERR, "%s", strerror(errno));
3429 		return NULL;
3430 	}
3431 
3432 	/* Count max number of sockets we may open */
3433 	for (maxs = 0, r = res; r; r = r->ai_next, maxs++)
3434 		;
3435 	socks = malloc((maxs + 1) * sizeof(int));
3436 	if (!socks) {
3437 		freeaddrinfo(res);
3438 		syslog(LOG_ERR, "couldn't allocate memory for sockets");
3439 		return NULL;
3440 	}
3441 
3442 	*socks = 0;   /* num of sockets counter at start of array */
3443 	s = socks + 1;
3444 	for (r = res; r; r = r->ai_next) {
3445 		*s = socket(r->ai_family, r->ai_socktype, r->ai_protocol);
3446 		if (*s < 0) {
3447 			syslog(LOG_DEBUG, "control socket: %m");
3448 			continue;
3449 		}
3450 		if (setsockopt(*s, SOL_SOCKET, SO_REUSEADDR,
3451 		    &on, sizeof(on)) < 0)
3452 			syslog(LOG_WARNING,
3453 			    "control setsockopt (SO_REUSEADDR): %m");
3454 		if (r->ai_family == AF_INET6) {
3455 			if (setsockopt(*s, IPPROTO_IPV6, IPV6_V6ONLY,
3456 			    &on, sizeof(on)) < 0)
3457 				syslog(LOG_WARNING,
3458 				    "control setsockopt (IPV6_V6ONLY): %m");
3459 		}
3460 		if (bind(*s, r->ai_addr, r->ai_addrlen) < 0) {
3461 			syslog(LOG_DEBUG, "control bind: %m");
3462 			close(*s);
3463 			continue;
3464 		}
3465 		(*socks)++;
3466 		s++;
3467 	}
3468 
3469 	if (res)
3470 		freeaddrinfo(res);
3471 
3472 	if (*socks == 0) {
3473 		syslog(LOG_ERR, "control socket: Couldn't bind to any socket");
3474 		free(socks);
3475 		return NULL;
3476 	}
3477 	return(socks);
3478 }
3479