xref: /freebsd/libexec/ftpd/ftpd.c (revision 2008043f386721d58158e37e0d7e50df8095942d)
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 /*
48  * FTP server.
49  */
50 #include <sys/param.h>
51 #include <sys/ioctl.h>
52 #include <sys/mman.h>
53 #include <sys/socket.h>
54 #include <sys/stat.h>
55 #include <sys/time.h>
56 #include <sys/wait.h>
57 
58 #include <netinet/in.h>
59 #include <netinet/in_systm.h>
60 #include <netinet/ip.h>
61 #include <netinet/tcp.h>
62 
63 #define	FTP_NAMES
64 #include <arpa/ftp.h>
65 #include <arpa/inet.h>
66 #include <arpa/telnet.h>
67 
68 #include <ctype.h>
69 #include <dirent.h>
70 #include <err.h>
71 #include <errno.h>
72 #include <fcntl.h>
73 #include <glob.h>
74 #include <limits.h>
75 #include <netdb.h>
76 #include <pwd.h>
77 #include <grp.h>
78 #include <signal.h>
79 #include <stdint.h>
80 #include <stdio.h>
81 #include <stdlib.h>
82 #include <string.h>
83 #include <syslog.h>
84 #include <time.h>
85 #include <unistd.h>
86 #include <libutil.h>
87 #ifdef	LOGIN_CAP
88 #include <login_cap.h>
89 #endif
90 
91 #ifdef USE_PAM
92 #include <security/pam_appl.h>
93 #endif
94 
95 #include "blacklist_client.h"
96 #include "pathnames.h"
97 #include "extern.h"
98 
99 #include <stdarg.h>
100 
101 static char version[] = "Version 6.00LS";
102 #undef main
103 
104 union sockunion ctrl_addr;
105 union sockunion data_source;
106 union sockunion data_dest;
107 union sockunion his_addr;
108 union sockunion pasv_addr;
109 
110 int	daemon_mode;
111 int	data;
112 int	dataport;
113 int	hostinfo = 1;	/* print host-specific info in messages */
114 int	logged_in;
115 struct	passwd *pw;
116 char	*homedir;
117 int	ftpdebug;
118 int	timeout = 900;    /* timeout after 15 minutes of inactivity */
119 int	maxtimeout = 7200;/* don't allow idle time to be set beyond 2 hours */
120 int	logging;
121 int	restricted_data_ports = 1;
122 int	paranoid = 1;	  /* be extra careful about security */
123 int	anon_only = 0;    /* Only anonymous ftp allowed */
124 int	assumeutf8 = 0;   /* Assume that server file names are in UTF-8 */
125 int	guest;
126 int	dochroot;
127 char	*chrootdir;
128 int	dowtmp = 1;
129 int	stats;
130 int	statfd = -1;
131 int	type;
132 int	form;
133 int	stru;			/* avoid C keyword */
134 int	mode;
135 int	usedefault = 1;		/* for data transfers */
136 int	pdata = -1;		/* for passive mode */
137 int	readonly = 0;		/* Server is in readonly mode.	*/
138 int	noepsv = 0;		/* EPSV command is disabled.	*/
139 int	noretr = 0;		/* RETR command is disabled.	*/
140 int	noguestretr = 0;	/* RETR command is disabled for anon users. */
141 int	noguestmkd = 0;		/* MKD command is disabled for anon users. */
142 int	noguestmod = 1;		/* anon users may not modify existing files. */
143 int	use_blacklist = 0;
144 
145 off_t	file_size;
146 off_t	byte_count;
147 #if !defined(CMASK) || CMASK == 0
148 #undef CMASK
149 #define CMASK 027
150 #endif
151 int	defumask = CMASK;		/* default umask value */
152 char	tmpline[7];
153 char	*hostname;
154 int	epsvall = 0;
155 
156 #ifdef VIRTUAL_HOSTING
157 char	*ftpuser;
158 
159 static struct ftphost {
160 	struct ftphost	*next;
161 	struct addrinfo *hostinfo;
162 	char		*hostname;
163 	char		*anonuser;
164 	char		*statfile;
165 	char		*welcome;
166 	char		*loginmsg;
167 } *thishost, *firsthost;
168 
169 #endif
170 char	remotehost[NI_MAXHOST];
171 char	*ident = NULL;
172 
173 static char	wtmpid[20];
174 
175 #ifdef USE_PAM
176 static int	auth_pam(struct passwd**, const char*);
177 pam_handle_t	*pamh = NULL;
178 #endif
179 
180 char	*pid_file = NULL; /* means default location to pidfile(3) */
181 
182 /*
183  * Limit number of pathnames that glob can return.
184  * A limit of 0 indicates the number of pathnames is unlimited.
185  */
186 #define MAXGLOBARGS	16384
187 #
188 
189 /*
190  * Timeout intervals for retrying connections
191  * to hosts that don't accept PORT cmds.  This
192  * is a kludge, but given the problems with TCP...
193  */
194 #define	SWAITMAX	90	/* wait at most 90 seconds */
195 #define	SWAITINT	5	/* interval between retries */
196 
197 int	swaitmax = SWAITMAX;
198 int	swaitint = SWAITINT;
199 
200 #ifdef SETPROCTITLE
201 char	proctitle[LINE_MAX];	/* initial part of title */
202 #endif /* SETPROCTITLE */
203 
204 #define LOGCMD(cmd, file)		logcmd((cmd), (file), NULL, -1)
205 #define LOGCMD2(cmd, file1, file2)	logcmd((cmd), (file1), (file2), -1)
206 #define LOGBYTES(cmd, file, cnt)	logcmd((cmd), (file), NULL, (cnt))
207 
208 static	volatile sig_atomic_t recvurg;
209 static	int transflag;		/* NB: for debugging only */
210 
211 #define STARTXFER	flagxfer(1)
212 #define ENDXFER		flagxfer(0)
213 
214 #define START_UNSAFE	maskurg(1)
215 #define END_UNSAFE	maskurg(0)
216 
217 /* It's OK to put an `else' clause after this macro. */
218 #define CHECKOOB(action)						\
219 	if (recvurg) {							\
220 		recvurg = 0;						\
221 		if (myoob()) {						\
222 			ENDXFER;					\
223 			action;						\
224 		}							\
225 	}
226 
227 #ifdef VIRTUAL_HOSTING
228 static void	 inithosts(int);
229 static void	 selecthost(union sockunion *);
230 #endif
231 static void	 ack(char *);
232 static void	 sigurg(int);
233 static void	 maskurg(int);
234 static void	 flagxfer(int);
235 static int	 myoob(void);
236 static int	 checkuser(char *, char *, int, char **, int *);
237 static FILE	*dataconn(char *, off_t, char *);
238 static void	 dolog(struct sockaddr *);
239 static void	 end_login(void);
240 static FILE	*getdatasock(char *);
241 static int	 guniquefd(char *, char **);
242 static void	 lostconn(int);
243 static void	 sigquit(int);
244 static int	 receive_data(FILE *, FILE *);
245 static int	 send_data(FILE *, FILE *, size_t, off_t, int);
246 static struct passwd *
247 		 sgetpwnam(char *);
248 static char	*sgetsave(char *);
249 static void	 reapchild(int);
250 static void	 appendf(char **, char *, ...) __printflike(2, 3);
251 static void	 logcmd(char *, char *, char *, off_t);
252 static void      logxfer(char *, off_t, time_t);
253 static char	*doublequote(char *);
254 static int	*socksetup(int, char *, const char *);
255 
256 int
257 main(int argc, char *argv[], char **envp)
258 {
259 	socklen_t addrlen;
260 	int ch, on = 1, tos, s = STDIN_FILENO;
261 	char *cp, line[LINE_MAX];
262 	FILE *fd;
263 	char	*bindname = NULL;
264 	const char *bindport = "ftp";
265 	int	family = AF_UNSPEC;
266 	struct sigaction sa;
267 
268 	tzset();		/* in case no timezone database in ~ftp */
269 	sigemptyset(&sa.sa_mask);
270 	sa.sa_flags = SA_RESTART;
271 
272 	/*
273 	 * Prevent diagnostic messages from appearing on stderr.
274 	 * We run as a daemon or from inetd; in both cases, there's
275 	 * more reason in logging to syslog.
276 	 */
277 	(void) freopen(_PATH_DEVNULL, "w", stderr);
278 	opterr = 0;
279 
280 	/*
281 	 * LOG_NDELAY sets up the logging connection immediately,
282 	 * necessary for anonymous ftp's that chroot and can't do it later.
283 	 */
284 	openlog("ftpd", LOG_PID | LOG_NDELAY, LOG_FTP);
285 
286 	while ((ch = getopt(argc, argv,
287 	                    "468a:ABdDEhlmMoOp:P:rRSt:T:u:UvW")) != -1) {
288 		switch (ch) {
289 		case '4':
290 			family = (family == AF_INET6) ? AF_UNSPEC : AF_INET;
291 			break;
292 
293 		case '6':
294 			family = (family == AF_INET) ? AF_UNSPEC : AF_INET6;
295 			break;
296 
297 		case '8':
298 			assumeutf8 = 1;
299 			break;
300 
301 		case 'a':
302 			bindname = optarg;
303 			break;
304 
305 		case 'A':
306 			anon_only = 1;
307 			break;
308 
309 		case 'B':
310 #ifdef USE_BLACKLIST
311 			use_blacklist = 1;
312 #else
313 			syslog(LOG_WARNING, "not compiled with USE_BLACKLIST support");
314 #endif
315 			break;
316 
317 		case 'd':
318 			ftpdebug++;
319 			break;
320 
321 		case 'D':
322 			daemon_mode++;
323 			break;
324 
325 		case 'E':
326 			noepsv = 1;
327 			break;
328 
329 		case 'h':
330 			hostinfo = 0;
331 			break;
332 
333 		case 'l':
334 			logging++;	/* > 1 == extra logging */
335 			break;
336 
337 		case 'm':
338 			noguestmod = 0;
339 			break;
340 
341 		case 'M':
342 			noguestmkd = 1;
343 			break;
344 
345 		case 'o':
346 			noretr = 1;
347 			break;
348 
349 		case 'O':
350 			noguestretr = 1;
351 			break;
352 
353 		case 'p':
354 			pid_file = optarg;
355 			break;
356 
357 		case 'P':
358 			bindport = optarg;
359 			break;
360 
361 		case 'r':
362 			readonly = 1;
363 			break;
364 
365 		case 'R':
366 			paranoid = 0;
367 			break;
368 
369 		case 'S':
370 			stats++;
371 			break;
372 
373 		case 't':
374 			timeout = atoi(optarg);
375 			if (maxtimeout < timeout)
376 				maxtimeout = timeout;
377 			break;
378 
379 		case 'T':
380 			maxtimeout = atoi(optarg);
381 			if (timeout > maxtimeout)
382 				timeout = maxtimeout;
383 			break;
384 
385 		case 'u':
386 		    {
387 			long val = 0;
388 
389 			val = strtol(optarg, &optarg, 8);
390 			if (*optarg != '\0' || val < 0)
391 				syslog(LOG_WARNING, "bad value for -u");
392 			else
393 				defumask = val;
394 			break;
395 		    }
396 		case 'U':
397 			restricted_data_ports = 0;
398 			break;
399 
400 		case 'v':
401 			ftpdebug++;
402 			break;
403 
404 		case 'W':
405 			dowtmp = 0;
406 			break;
407 
408 		default:
409 			syslog(LOG_WARNING, "unknown flag -%c ignored", optopt);
410 			break;
411 		}
412 	}
413 
414 	/* handle filesize limit gracefully */
415 	sa.sa_handler = SIG_IGN;
416 	(void)sigaction(SIGXFSZ, &sa, NULL);
417 
418 	if (daemon_mode) {
419 		int *ctl_sock, fd, maxfd = -1, nfds, i;
420 		fd_set defreadfds, readfds;
421 		pid_t pid;
422 		struct pidfh *pfh;
423 
424 		if ((pfh = pidfile_open(pid_file, 0600, &pid)) == NULL) {
425 			if (errno == EEXIST) {
426 				syslog(LOG_ERR, "%s already running, pid %d",
427 				       getprogname(), (int)pid);
428 				exit(1);
429 			}
430 			syslog(LOG_WARNING, "pidfile_open: %m");
431 		}
432 
433 		/*
434 		 * Detach from parent.
435 		 */
436 		if (daemon(1, 1) < 0) {
437 			syslog(LOG_ERR, "failed to become a daemon");
438 			exit(1);
439 		}
440 
441 		if (pfh != NULL && pidfile_write(pfh) == -1)
442 			syslog(LOG_WARNING, "pidfile_write: %m");
443 
444 		sa.sa_handler = reapchild;
445 		(void)sigaction(SIGCHLD, &sa, NULL);
446 
447 #ifdef VIRTUAL_HOSTING
448 		inithosts(family);
449 #endif
450 
451 		/*
452 		 * Open a socket, bind it to the FTP port, and start
453 		 * listening.
454 		 */
455 		ctl_sock = socksetup(family, bindname, bindport);
456 		if (ctl_sock == NULL)
457 			exit(1);
458 
459 		FD_ZERO(&defreadfds);
460 		for (i = 1; i <= *ctl_sock; i++) {
461 			FD_SET(ctl_sock[i], &defreadfds);
462 			if (listen(ctl_sock[i], 32) < 0) {
463 				syslog(LOG_ERR, "control listen: %m");
464 				exit(1);
465 			}
466 			if (maxfd < ctl_sock[i])
467 				maxfd = ctl_sock[i];
468 		}
469 
470 		/*
471 		 * Loop forever accepting connection requests and forking off
472 		 * children to handle them.
473 		 */
474 		while (1) {
475 			FD_COPY(&defreadfds, &readfds);
476 			nfds = select(maxfd + 1, &readfds, NULL, NULL, 0);
477 			if (nfds <= 0) {
478 				if (nfds < 0 && errno != EINTR)
479 					syslog(LOG_WARNING, "select: %m");
480 				continue;
481 			}
482 
483 			pid = -1;
484                         for (i = 1; i <= *ctl_sock; i++)
485 				if (FD_ISSET(ctl_sock[i], &readfds)) {
486 					addrlen = sizeof(his_addr);
487 					fd = accept(ctl_sock[i],
488 					    (struct sockaddr *)&his_addr,
489 					    &addrlen);
490 					if (fd == -1) {
491 						syslog(LOG_WARNING,
492 						       "accept: %m");
493 						continue;
494 					}
495 					switch (pid = fork()) {
496 					case 0:
497 						/* child */
498 						(void) dup2(fd, s);
499 						(void) dup2(fd, STDOUT_FILENO);
500 						(void) close(fd);
501 						for (i = 1; i <= *ctl_sock; i++)
502 							close(ctl_sock[i]);
503 						if (pfh != NULL)
504 							pidfile_close(pfh);
505 						goto gotchild;
506 					case -1:
507 						syslog(LOG_WARNING, "fork: %m");
508 						/* FALLTHROUGH */
509 					default:
510 						close(fd);
511 					}
512 				}
513 		}
514 	} else {
515 		addrlen = sizeof(his_addr);
516 		if (getpeername(s, (struct sockaddr *)&his_addr, &addrlen) < 0) {
517 			syslog(LOG_ERR, "getpeername (%s): %m",argv[0]);
518 			exit(1);
519 		}
520 
521 #ifdef VIRTUAL_HOSTING
522 		if (his_addr.su_family == AF_INET6 &&
523 		    IN6_IS_ADDR_V4MAPPED(&his_addr.su_sin6.sin6_addr))
524 			family = AF_INET;
525 		else
526 			family = his_addr.su_family;
527 		inithosts(family);
528 #endif
529 	}
530 
531 gotchild:
532 	sa.sa_handler = SIG_DFL;
533 	(void)sigaction(SIGCHLD, &sa, NULL);
534 
535 	sa.sa_handler = sigurg;
536 	sa.sa_flags = 0;		/* don't restart syscalls for SIGURG */
537 	(void)sigaction(SIGURG, &sa, NULL);
538 
539 	sigfillset(&sa.sa_mask);	/* block all signals in handler */
540 	sa.sa_flags = SA_RESTART;
541 	sa.sa_handler = sigquit;
542 	(void)sigaction(SIGHUP, &sa, NULL);
543 	(void)sigaction(SIGINT, &sa, NULL);
544 	(void)sigaction(SIGQUIT, &sa, NULL);
545 	(void)sigaction(SIGTERM, &sa, NULL);
546 
547 	sa.sa_handler = lostconn;
548 	(void)sigaction(SIGPIPE, &sa, NULL);
549 
550 	addrlen = sizeof(ctrl_addr);
551 	if (getsockname(s, (struct sockaddr *)&ctrl_addr, &addrlen) < 0) {
552 		syslog(LOG_ERR, "getsockname (%s): %m",argv[0]);
553 		exit(1);
554 	}
555 	dataport = ntohs(ctrl_addr.su_port) - 1; /* as per RFC 959 */
556 #ifdef VIRTUAL_HOSTING
557 	/* select our identity from virtual host table */
558 	selecthost(&ctrl_addr);
559 #endif
560 #ifdef IP_TOS
561 	if (ctrl_addr.su_family == AF_INET)
562       {
563 	tos = IPTOS_LOWDELAY;
564 	if (setsockopt(s, IPPROTO_IP, IP_TOS, &tos, sizeof(int)) < 0)
565 		syslog(LOG_WARNING, "control setsockopt (IP_TOS): %m");
566       }
567 #endif
568 	/*
569 	 * Disable Nagle on the control channel so that we don't have to wait
570 	 * for peer's ACK before issuing our next reply.
571 	 */
572 	if (setsockopt(s, IPPROTO_TCP, TCP_NODELAY, &on, sizeof(on)) < 0)
573 		syslog(LOG_WARNING, "control setsockopt (TCP_NODELAY): %m");
574 
575 	data_source.su_port = htons(ntohs(ctrl_addr.su_port) - 1);
576 
577 	(void)snprintf(wtmpid, sizeof(wtmpid), "%xftpd", getpid());
578 
579 	/* Try to handle urgent data inline */
580 #ifdef SO_OOBINLINE
581 	if (setsockopt(s, SOL_SOCKET, SO_OOBINLINE, &on, sizeof(on)) < 0)
582 		syslog(LOG_WARNING, "control setsockopt (SO_OOBINLINE): %m");
583 #endif
584 
585 #ifdef	F_SETOWN
586 	if (fcntl(s, F_SETOWN, getpid()) == -1)
587 		syslog(LOG_ERR, "fcntl F_SETOWN: %m");
588 #endif
589 	dolog((struct sockaddr *)&his_addr);
590 	/*
591 	 * Set up default state
592 	 */
593 	data = -1;
594 	type = TYPE_A;
595 	form = FORM_N;
596 	stru = STRU_F;
597 	mode = MODE_S;
598 	tmpline[0] = '\0';
599 
600 	/* If logins are disabled, print out the message. */
601 	if ((fd = fopen(_PATH_NOLOGIN,"r")) != NULL) {
602 		while (fgets(line, sizeof(line), fd) != NULL) {
603 			if ((cp = strchr(line, '\n')) != NULL)
604 				*cp = '\0';
605 			lreply(530, "%s", line);
606 		}
607 		(void) fflush(stdout);
608 		(void) fclose(fd);
609 		reply(530, "System not available.");
610 		exit(0);
611 	}
612 #ifdef VIRTUAL_HOSTING
613 	fd = fopen(thishost->welcome, "r");
614 #else
615 	fd = fopen(_PATH_FTPWELCOME, "r");
616 #endif
617 	if (fd != NULL) {
618 		while (fgets(line, sizeof(line), fd) != NULL) {
619 			if ((cp = strchr(line, '\n')) != NULL)
620 				*cp = '\0';
621 			lreply(220, "%s", line);
622 		}
623 		(void) fflush(stdout);
624 		(void) fclose(fd);
625 		/* reply(220,) must follow */
626 	}
627 #ifndef VIRTUAL_HOSTING
628 	if ((hostname = malloc(MAXHOSTNAMELEN)) == NULL)
629 		fatalerror("Ran out of memory.");
630 	if (gethostname(hostname, MAXHOSTNAMELEN - 1) < 0)
631 		hostname[0] = '\0';
632 	hostname[MAXHOSTNAMELEN - 1] = '\0';
633 #endif
634 	if (hostinfo)
635 		reply(220, "%s FTP server (%s) ready.", hostname, version);
636 	else
637 		reply(220, "FTP server ready.");
638 	BLACKLIST_INIT();
639 	for (;;)
640 		(void) yyparse();
641 	/* NOTREACHED */
642 }
643 
644 static void
645 lostconn(int signo)
646 {
647 
648 	if (ftpdebug)
649 		syslog(LOG_DEBUG, "lost connection");
650 	dologout(1);
651 }
652 
653 static void
654 sigquit(int signo)
655 {
656 
657 	syslog(LOG_ERR, "got signal %d", signo);
658 	dologout(1);
659 }
660 
661 #ifdef VIRTUAL_HOSTING
662 /*
663  * read in virtual host tables (if they exist)
664  */
665 
666 static void
667 inithosts(int family)
668 {
669 	int insert;
670 	size_t len;
671 	FILE *fp;
672 	char *cp, *mp, *line;
673 	char *hostname;
674 	char *vhost, *anonuser, *statfile, *welcome, *loginmsg;
675 	struct ftphost *hrp, *lhrp;
676 	struct addrinfo hints, *res, *ai;
677 
678 	/*
679 	 * Fill in the default host information
680 	 */
681 	if ((hostname = malloc(MAXHOSTNAMELEN)) == NULL)
682 		fatalerror("Ran out of memory.");
683 	if (gethostname(hostname, MAXHOSTNAMELEN - 1) < 0)
684 		hostname[0] = '\0';
685 	hostname[MAXHOSTNAMELEN - 1] = '\0';
686 	if ((hrp = malloc(sizeof(struct ftphost))) == NULL)
687 		fatalerror("Ran out of memory.");
688 	hrp->hostname = hostname;
689 	hrp->hostinfo = NULL;
690 
691 	memset(&hints, 0, sizeof(hints));
692 	hints.ai_flags = AI_PASSIVE;
693 	hints.ai_family = family;
694 	hints.ai_socktype = SOCK_STREAM;
695 	if (getaddrinfo(hrp->hostname, NULL, &hints, &res) == 0)
696 		hrp->hostinfo = res;
697 	hrp->statfile = _PATH_FTPDSTATFILE;
698 	hrp->welcome  = _PATH_FTPWELCOME;
699 	hrp->loginmsg = _PATH_FTPLOGINMESG;
700 	hrp->anonuser = "ftp";
701 	hrp->next = NULL;
702 	thishost = firsthost = lhrp = hrp;
703 	if ((fp = fopen(_PATH_FTPHOSTS, "r")) != NULL) {
704 		int addrsize, gothost;
705 		void *addr;
706 		struct hostent *hp;
707 
708 		while ((line = fgetln(fp, &len)) != NULL) {
709 			int	i, hp_error;
710 
711 			/* skip comments */
712 			if (line[0] == '#')
713 				continue;
714 			if (line[len - 1] == '\n') {
715 				line[len - 1] = '\0';
716 				mp = NULL;
717 			} else {
718 				if ((mp = malloc(len + 1)) == NULL)
719 					fatalerror("Ran out of memory.");
720 				memcpy(mp, line, len);
721 				mp[len] = '\0';
722 				line = mp;
723 			}
724 			cp = strtok(line, " \t");
725 			/* skip empty lines */
726 			if (cp == NULL)
727 				goto nextline;
728 			vhost = cp;
729 
730 			/* set defaults */
731 			anonuser = "ftp";
732 			statfile = _PATH_FTPDSTATFILE;
733 			welcome  = _PATH_FTPWELCOME;
734 			loginmsg = _PATH_FTPLOGINMESG;
735 
736 			/*
737 			 * Preparse the line so we can use its info
738 			 * for all the addresses associated with
739 			 * the virtual host name.
740 			 * Field 0, the virtual host name, is special:
741 			 * it's already parsed off and will be strdup'ed
742 			 * later, after we know its canonical form.
743 			 */
744 			for (i = 1; i < 5 && (cp = strtok(NULL, " \t")); i++)
745 				if (*cp != '-' && (cp = strdup(cp)))
746 					switch (i) {
747 					case 1:	/* anon user permissions */
748 						anonuser = cp;
749 						break;
750 					case 2: /* statistics file */
751 						statfile = cp;
752 						break;
753 					case 3: /* welcome message */
754 						welcome  = cp;
755 						break;
756 					case 4: /* login message */
757 						loginmsg = cp;
758 						break;
759 					default: /* programming error */
760 						abort();
761 						/* NOTREACHED */
762 					}
763 
764 			hints.ai_flags = AI_PASSIVE;
765 			hints.ai_family = family;
766 			hints.ai_socktype = SOCK_STREAM;
767 			if (getaddrinfo(vhost, NULL, &hints, &res) != 0)
768 				goto nextline;
769 			for (ai = res; ai != NULL && ai->ai_addr != NULL;
770 			     ai = ai->ai_next) {
771 
772 			gothost = 0;
773 			for (hrp = firsthost; hrp != NULL; hrp = hrp->next) {
774 				struct addrinfo *hi;
775 
776 				for (hi = hrp->hostinfo; hi != NULL;
777 				     hi = hi->ai_next)
778 					if (hi->ai_addrlen == ai->ai_addrlen &&
779 					    memcmp(hi->ai_addr,
780 						   ai->ai_addr,
781 						   ai->ai_addr->sa_len) == 0) {
782 						gothost++;
783 						break;
784 					}
785 				if (gothost)
786 					break;
787 			}
788 			if (hrp == NULL) {
789 				if ((hrp = malloc(sizeof(struct ftphost))) == NULL)
790 					goto nextline;
791 				hrp->hostname = NULL;
792 				insert = 1;
793 			} else {
794 				if (hrp->hostinfo && hrp->hostinfo != res)
795 					freeaddrinfo(hrp->hostinfo);
796 				insert = 0; /* host already in the chain */
797 			}
798 			hrp->hostinfo = res;
799 
800 			/*
801 			 * determine hostname to use.
802 			 * force defined name if there is a valid alias
803 			 * otherwise fallback to primary hostname
804 			 */
805 			/* XXX: getaddrinfo() can't do alias check */
806 			switch(hrp->hostinfo->ai_family) {
807 			case AF_INET:
808 				addr = &((struct sockaddr_in *)hrp->hostinfo->ai_addr)->sin_addr;
809 				addrsize = sizeof(struct in_addr);
810 				break;
811 			case AF_INET6:
812 				addr = &((struct sockaddr_in6 *)hrp->hostinfo->ai_addr)->sin6_addr;
813 				addrsize = sizeof(struct in6_addr);
814 				break;
815 			default:
816 				/* should not reach here */
817 				freeaddrinfo(hrp->hostinfo);
818 				if (insert)
819 					free(hrp); /*not in chain, can free*/
820 				else
821 					hrp->hostinfo = NULL; /*mark as blank*/
822 				goto nextline;
823 				/* NOTREACHED */
824 			}
825 			if ((hp = getipnodebyaddr(addr, addrsize,
826 						  hrp->hostinfo->ai_family,
827 						  &hp_error)) != NULL) {
828 				if (strcmp(vhost, hp->h_name) != 0) {
829 					if (hp->h_aliases == NULL)
830 						vhost = hp->h_name;
831 					else {
832 						i = 0;
833 						while (hp->h_aliases[i] &&
834 						       strcmp(vhost, hp->h_aliases[i]) != 0)
835 							++i;
836 						if (hp->h_aliases[i] == NULL)
837 							vhost = hp->h_name;
838 					}
839 				}
840 			}
841 			if (hrp->hostname &&
842 			    strcmp(hrp->hostname, vhost) != 0) {
843 				free(hrp->hostname);
844 				hrp->hostname = NULL;
845 			}
846 			if (hrp->hostname == NULL &&
847 			    (hrp->hostname = strdup(vhost)) == NULL) {
848 				freeaddrinfo(hrp->hostinfo);
849 				hrp->hostinfo = NULL; /* mark as blank */
850 				if (hp)
851 					freehostent(hp);
852 				goto nextline;
853 			}
854 			hrp->anonuser = anonuser;
855 			hrp->statfile = statfile;
856 			hrp->welcome  = welcome;
857 			hrp->loginmsg = loginmsg;
858 			if (insert) {
859 				hrp->next  = NULL;
860 				lhrp->next = hrp;
861 				lhrp = hrp;
862 			}
863 			if (hp)
864 				freehostent(hp);
865 		      }
866 nextline:
867 			if (mp)
868 				free(mp);
869 		}
870 		(void) fclose(fp);
871 	}
872 }
873 
874 static void
875 selecthost(union sockunion *su)
876 {
877 	struct ftphost	*hrp;
878 	u_int16_t port;
879 #ifdef INET6
880 	struct in6_addr *mapped_in6 = NULL;
881 #endif
882 	struct addrinfo *hi;
883 
884 #ifdef INET6
885 	/*
886 	 * XXX IPv4 mapped IPv6 addr consideraton,
887 	 * specified in rfc2373.
888 	 */
889 	if (su->su_family == AF_INET6 &&
890 	    IN6_IS_ADDR_V4MAPPED(&su->su_sin6.sin6_addr))
891 		mapped_in6 = &su->su_sin6.sin6_addr;
892 #endif
893 
894 	hrp = thishost = firsthost;	/* default */
895 	port = su->su_port;
896 	su->su_port = 0;
897 	while (hrp != NULL) {
898 	    for (hi = hrp->hostinfo; hi != NULL; hi = hi->ai_next) {
899 		if (memcmp(su, hi->ai_addr, hi->ai_addrlen) == 0) {
900 			thishost = hrp;
901 			goto found;
902 		}
903 #ifdef INET6
904 		/* XXX IPv4 mapped IPv6 addr consideraton */
905 		if (hi->ai_addr->sa_family == AF_INET && mapped_in6 != NULL &&
906 		    (memcmp(&mapped_in6->s6_addr[12],
907 			    &((struct sockaddr_in *)hi->ai_addr)->sin_addr,
908 			    sizeof(struct in_addr)) == 0)) {
909 			thishost = hrp;
910 			goto found;
911 		}
912 #endif
913 	    }
914 	    hrp = hrp->next;
915 	}
916 found:
917 	su->su_port = port;
918 	/* setup static variables as appropriate */
919 	hostname = thishost->hostname;
920 	ftpuser = thishost->anonuser;
921 }
922 #endif
923 
924 /*
925  * Helper function for sgetpwnam().
926  */
927 static char *
928 sgetsave(char *s)
929 {
930 	char *new = malloc(strlen(s) + 1);
931 
932 	if (new == NULL) {
933 		reply(421, "Ran out of memory.");
934 		dologout(1);
935 		/* NOTREACHED */
936 	}
937 	(void) strcpy(new, s);
938 	return (new);
939 }
940 
941 /*
942  * Save the result of a getpwnam.  Used for USER command, since
943  * the data returned must not be clobbered by any other command
944  * (e.g., globbing).
945  * NB: The data returned by sgetpwnam() will remain valid until
946  * the next call to this function.  Its difference from getpwnam()
947  * is that sgetpwnam() is known to be called from ftpd code only.
948  */
949 static struct passwd *
950 sgetpwnam(char *name)
951 {
952 	static struct passwd save;
953 	struct passwd *p;
954 
955 	if ((p = getpwnam(name)) == NULL)
956 		return (p);
957 	if (save.pw_name) {
958 		free(save.pw_name);
959 		free(save.pw_passwd);
960 		free(save.pw_class);
961 		free(save.pw_gecos);
962 		free(save.pw_dir);
963 		free(save.pw_shell);
964 	}
965 	save = *p;
966 	save.pw_name = sgetsave(p->pw_name);
967 	save.pw_passwd = sgetsave(p->pw_passwd);
968 	save.pw_class = sgetsave(p->pw_class);
969 	save.pw_gecos = sgetsave(p->pw_gecos);
970 	save.pw_dir = sgetsave(p->pw_dir);
971 	save.pw_shell = sgetsave(p->pw_shell);
972 	return (&save);
973 }
974 
975 static int login_attempts;	/* number of failed login attempts */
976 static int askpasswd;		/* had user command, ask for passwd */
977 static char curname[MAXLOGNAME];	/* current USER name */
978 
979 /*
980  * USER command.
981  * Sets global passwd pointer pw if named account exists and is acceptable;
982  * sets askpasswd if a PASS command is expected.  If logged in previously,
983  * need to reset state.  If name is "ftp" or "anonymous", the name is not in
984  * _PATH_FTPUSERS, and ftp account exists, set guest and pw, then just return.
985  * If account doesn't exist, ask for passwd anyway.  Otherwise, check user
986  * requesting login privileges.  Disallow anyone who does not have a standard
987  * shell as returned by getusershell().  Disallow anyone mentioned in the file
988  * _PATH_FTPUSERS to allow people such as root and uucp to be avoided.
989  */
990 void
991 user(char *name)
992 {
993 	int ecode;
994 	char *cp, *shell;
995 
996 	if (logged_in) {
997 		if (guest) {
998 			reply(530, "Can't change user from guest login.");
999 			return;
1000 		} else if (dochroot) {
1001 			reply(530, "Can't change user from chroot user.");
1002 			return;
1003 		}
1004 		end_login();
1005 	}
1006 
1007 	guest = 0;
1008 #ifdef VIRTUAL_HOSTING
1009 	pw = sgetpwnam(thishost->anonuser);
1010 #else
1011 	pw = sgetpwnam("ftp");
1012 #endif
1013 	if (strcmp(name, "ftp") == 0 || strcmp(name, "anonymous") == 0) {
1014 		if (checkuser(_PATH_FTPUSERS, "ftp", 0, NULL, &ecode) ||
1015 		    (ecode != 0 && ecode != ENOENT))
1016 			reply(530, "User %s access denied.", name);
1017 		else if (checkuser(_PATH_FTPUSERS, "anonymous", 0, NULL, &ecode) ||
1018 		    (ecode != 0 && ecode != ENOENT))
1019 			reply(530, "User %s access denied.", name);
1020 		else if (pw != NULL) {
1021 			guest = 1;
1022 			askpasswd = 1;
1023 			reply(331,
1024 			"Guest login ok, send your email address as password.");
1025 		} else
1026 			reply(530, "User %s unknown.", name);
1027 		if (!askpasswd && logging)
1028 			syslog(LOG_NOTICE,
1029 			    "ANONYMOUS FTP LOGIN REFUSED FROM %s", remotehost);
1030 		return;
1031 	}
1032 	if (anon_only != 0) {
1033 		reply(530, "Sorry, only anonymous ftp allowed.");
1034 		return;
1035 	}
1036 
1037 	if ((pw = sgetpwnam(name))) {
1038 		if ((shell = pw->pw_shell) == NULL || *shell == 0)
1039 			shell = _PATH_BSHELL;
1040 		setusershell();
1041 		while ((cp = getusershell()) != NULL)
1042 			if (strcmp(cp, shell) == 0)
1043 				break;
1044 		endusershell();
1045 
1046 		if (cp == NULL ||
1047 		    (checkuser(_PATH_FTPUSERS, name, 1, NULL, &ecode) ||
1048 		    (ecode != 0 && ecode != ENOENT))) {
1049 			reply(530, "User %s access denied.", name);
1050 			if (logging)
1051 				syslog(LOG_NOTICE,
1052 				    "FTP LOGIN REFUSED FROM %s, %s",
1053 				    remotehost, name);
1054 			pw = NULL;
1055 			return;
1056 		}
1057 	}
1058 	if (logging)
1059 		strlcpy(curname, name, sizeof(curname));
1060 
1061 	reply(331, "Password required for %s.", name);
1062 	askpasswd = 1;
1063 	/*
1064 	 * Delay before reading passwd after first failed
1065 	 * attempt to slow down passwd-guessing programs.
1066 	 */
1067 	if (login_attempts)
1068 		sleep(login_attempts);
1069 }
1070 
1071 /*
1072  * Check if a user is in the file "fname",
1073  * return a pointer to a malloc'd string with the rest
1074  * of the matching line in "residue" if not NULL.
1075  */
1076 static int
1077 checkuser(char *fname, char *name, int pwset, char **residue, int *ecode)
1078 {
1079 	FILE *fd;
1080 	int found = 0;
1081 	size_t len;
1082 	char *line, *mp, *p;
1083 
1084 	if (ecode != NULL)
1085 		*ecode = 0;
1086 	if ((fd = fopen(fname, "r")) != NULL) {
1087 		while (!found && (line = fgetln(fd, &len)) != NULL) {
1088 			/* skip comments */
1089 			if (line[0] == '#')
1090 				continue;
1091 			if (line[len - 1] == '\n') {
1092 				line[len - 1] = '\0';
1093 				mp = NULL;
1094 			} else {
1095 				if ((mp = malloc(len + 1)) == NULL)
1096 					fatalerror("Ran out of memory.");
1097 				memcpy(mp, line, len);
1098 				mp[len] = '\0';
1099 				line = mp;
1100 			}
1101 			/* avoid possible leading and trailing whitespace */
1102 			p = strtok(line, " \t");
1103 			/* skip empty lines */
1104 			if (p == NULL)
1105 				goto nextline;
1106 			/*
1107 			 * if first chr is '@', check group membership
1108 			 */
1109 			if (p[0] == '@') {
1110 				int i = 0;
1111 				struct group *grp;
1112 
1113 				if (p[1] == '\0') /* single @ matches anyone */
1114 					found = 1;
1115 				else {
1116 					if ((grp = getgrnam(p+1)) == NULL)
1117 						goto nextline;
1118 					/*
1119 					 * Check user's default group
1120 					 */
1121 					if (pwset && grp->gr_gid == pw->pw_gid)
1122 						found = 1;
1123 					/*
1124 					 * Check supplementary groups
1125 					 */
1126 					while (!found && grp->gr_mem[i])
1127 						found = strcmp(name,
1128 							grp->gr_mem[i++])
1129 							== 0;
1130 				}
1131 			}
1132 			/*
1133 			 * Otherwise, just check for username match
1134 			 */
1135 			else
1136 				found = strcmp(p, name) == 0;
1137 			/*
1138 			 * Save the rest of line to "residue" if matched
1139 			 */
1140 			if (found && residue) {
1141 				if ((p = strtok(NULL, "")) != NULL)
1142 					p += strspn(p, " \t");
1143 				if (p && *p) {
1144 				 	if ((*residue = strdup(p)) == NULL)
1145 						fatalerror("Ran out of memory.");
1146 				} else
1147 					*residue = NULL;
1148 			}
1149 nextline:
1150 			if (mp)
1151 				free(mp);
1152 		}
1153 		(void) fclose(fd);
1154 	} else if (ecode != NULL)
1155 		*ecode = errno;
1156 	return (found);
1157 }
1158 
1159 /*
1160  * Terminate login as previous user, if any, resetting state;
1161  * used when USER command is given or login fails.
1162  */
1163 static void
1164 end_login(void)
1165 {
1166 #ifdef USE_PAM
1167 	int e;
1168 #endif
1169 
1170 	(void) seteuid(0);
1171 #ifdef	LOGIN_CAP
1172 	setusercontext(NULL, getpwuid(0), 0, LOGIN_SETALL & ~(LOGIN_SETLOGIN |
1173 		       LOGIN_SETUSER | LOGIN_SETGROUP | LOGIN_SETPATH |
1174 		       LOGIN_SETENV));
1175 #endif
1176 	if (logged_in && dowtmp)
1177 		ftpd_logwtmp(wtmpid, NULL, NULL);
1178 	pw = NULL;
1179 #ifdef USE_PAM
1180 	if (pamh) {
1181 		if ((e = pam_setcred(pamh, PAM_DELETE_CRED)) != PAM_SUCCESS)
1182 			syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, e));
1183 		if ((e = pam_close_session(pamh,0)) != PAM_SUCCESS)
1184 			syslog(LOG_ERR, "pam_close_session: %s", pam_strerror(pamh, e));
1185 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS)
1186 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1187 		pamh = NULL;
1188 	}
1189 #endif
1190 	logged_in = 0;
1191 	guest = 0;
1192 	dochroot = 0;
1193 }
1194 
1195 #ifdef USE_PAM
1196 
1197 /*
1198  * the following code is stolen from imap-uw PAM authentication module and
1199  * login.c
1200  */
1201 #define COPY_STRING(s) (s ? strdup(s) : NULL)
1202 
1203 struct cred_t {
1204 	const char *uname;		/* user name */
1205 	const char *pass;		/* password */
1206 };
1207 typedef struct cred_t cred_t;
1208 
1209 static int
1210 auth_conv(int num_msg, const struct pam_message **msg,
1211 	  struct pam_response **resp, void *appdata)
1212 {
1213 	int i;
1214 	cred_t *cred = (cred_t *) appdata;
1215 	struct pam_response *reply;
1216 
1217 	reply = calloc(num_msg, sizeof *reply);
1218 	if (reply == NULL)
1219 		return PAM_BUF_ERR;
1220 
1221 	for (i = 0; i < num_msg; i++) {
1222 		switch (msg[i]->msg_style) {
1223 		case PAM_PROMPT_ECHO_ON:	/* assume want user name */
1224 			reply[i].resp_retcode = PAM_SUCCESS;
1225 			reply[i].resp = COPY_STRING(cred->uname);
1226 			/* PAM frees resp. */
1227 			break;
1228 		case PAM_PROMPT_ECHO_OFF:	/* assume want password */
1229 			reply[i].resp_retcode = PAM_SUCCESS;
1230 			reply[i].resp = COPY_STRING(cred->pass);
1231 			/* PAM frees resp. */
1232 			break;
1233 		case PAM_TEXT_INFO:
1234 		case PAM_ERROR_MSG:
1235 			reply[i].resp_retcode = PAM_SUCCESS;
1236 			reply[i].resp = NULL;
1237 			break;
1238 		default:			/* unknown message style */
1239 			free(reply);
1240 			return PAM_CONV_ERR;
1241 		}
1242 	}
1243 
1244 	*resp = reply;
1245 	return PAM_SUCCESS;
1246 }
1247 
1248 /*
1249  * Attempt to authenticate the user using PAM.  Returns 0 if the user is
1250  * authenticated, or 1 if not authenticated.  If some sort of PAM system
1251  * error occurs (e.g., the "/etc/pam.conf" file is missing) then this
1252  * function returns -1.  This can be used as an indication that we should
1253  * fall back to a different authentication mechanism.
1254  */
1255 static int
1256 auth_pam(struct passwd **ppw, const char *pass)
1257 {
1258 	const char *tmpl_user;
1259 	const void *item;
1260 	int rval;
1261 	int e;
1262 	cred_t auth_cred = { (*ppw)->pw_name, pass };
1263 	struct pam_conv conv = { &auth_conv, &auth_cred };
1264 
1265 	e = pam_start("ftpd", (*ppw)->pw_name, &conv, &pamh);
1266 	if (e != PAM_SUCCESS) {
1267 		/*
1268 		 * In OpenPAM, it's OK to pass NULL to pam_strerror()
1269 		 * if context creation has failed in the first place.
1270 		 */
1271 		syslog(LOG_ERR, "pam_start: %s", pam_strerror(NULL, e));
1272 		return -1;
1273 	}
1274 
1275 	e = pam_set_item(pamh, PAM_RHOST, remotehost);
1276 	if (e != PAM_SUCCESS) {
1277 		syslog(LOG_ERR, "pam_set_item(PAM_RHOST): %s",
1278 			pam_strerror(pamh, e));
1279 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
1280 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1281 		}
1282 		pamh = NULL;
1283 		return -1;
1284 	}
1285 
1286 	e = pam_authenticate(pamh, 0);
1287 	switch (e) {
1288 	case PAM_SUCCESS:
1289 		/*
1290 		 * With PAM we support the concept of a "template"
1291 		 * user.  The user enters a login name which is
1292 		 * authenticated by PAM, usually via a remote service
1293 		 * such as RADIUS or TACACS+.  If authentication
1294 		 * succeeds, a different but related "template" name
1295 		 * is used for setting the credentials, shell, and
1296 		 * home directory.  The name the user enters need only
1297 		 * exist on the remote authentication server, but the
1298 		 * template name must be present in the local password
1299 		 * database.
1300 		 *
1301 		 * This is supported by two various mechanisms in the
1302 		 * individual modules.  However, from the application's
1303 		 * point of view, the template user is always passed
1304 		 * back as a changed value of the PAM_USER item.
1305 		 */
1306 		if ((e = pam_get_item(pamh, PAM_USER, &item)) ==
1307 		    PAM_SUCCESS) {
1308 			tmpl_user = (const char *) item;
1309 			if (strcmp((*ppw)->pw_name, tmpl_user) != 0)
1310 				*ppw = getpwnam(tmpl_user);
1311 		} else
1312 			syslog(LOG_ERR, "Couldn't get PAM_USER: %s",
1313 			    pam_strerror(pamh, e));
1314 		rval = 0;
1315 		break;
1316 
1317 	case PAM_AUTH_ERR:
1318 	case PAM_USER_UNKNOWN:
1319 	case PAM_MAXTRIES:
1320 		rval = 1;
1321 		break;
1322 
1323 	default:
1324 		syslog(LOG_ERR, "pam_authenticate: %s", pam_strerror(pamh, e));
1325 		rval = -1;
1326 		break;
1327 	}
1328 
1329 	if (rval == 0) {
1330 		e = pam_acct_mgmt(pamh, 0);
1331 		if (e != PAM_SUCCESS) {
1332 			syslog(LOG_ERR, "pam_acct_mgmt: %s",
1333 						pam_strerror(pamh, e));
1334 			rval = 1;
1335 		}
1336 	}
1337 
1338 	if (rval != 0) {
1339 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
1340 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1341 		}
1342 		pamh = NULL;
1343 	}
1344 	return rval;
1345 }
1346 
1347 #endif /* USE_PAM */
1348 
1349 void
1350 pass(char *passwd)
1351 {
1352 	int rval, ecode;
1353 	FILE *fd;
1354 #ifdef	LOGIN_CAP
1355 	login_cap_t *lc = NULL;
1356 #endif
1357 #ifdef USE_PAM
1358 	int e;
1359 #endif
1360 	char *residue = NULL;
1361 	char *xpasswd;
1362 
1363 	if (logged_in || askpasswd == 0) {
1364 		reply(503, "Login with USER first.");
1365 		return;
1366 	}
1367 	askpasswd = 0;
1368 	if (!guest) {		/* "ftp" is only account allowed no password */
1369 		if (pw == NULL) {
1370 			rval = 1;	/* failure below */
1371 			goto skip;
1372 		}
1373 #ifdef USE_PAM
1374 		rval = auth_pam(&pw, passwd);
1375 		if (rval >= 0) {
1376 			goto skip;
1377 		}
1378 #endif
1379 		xpasswd = crypt(passwd, pw->pw_passwd);
1380 		if (passwd[0] == '\0' && pw->pw_passwd[0] != '\0')
1381 			xpasswd = ":";
1382 		rval = strcmp(pw->pw_passwd, xpasswd);
1383 		if (pw->pw_expire && time(NULL) >= pw->pw_expire)
1384 			rval = 1;	/* failure */
1385 skip:
1386 		/*
1387 		 * If rval == 1, the user failed the authentication check
1388 		 * above.  If rval == 0, either PAM or local authentication
1389 		 * succeeded.
1390 		 */
1391 		if (rval) {
1392 			reply(530, "Login incorrect.");
1393 			BLACKLIST_NOTIFY(BLACKLIST_AUTH_FAIL, STDIN_FILENO, "Login incorrect");
1394 			if (logging) {
1395 				syslog(LOG_NOTICE,
1396 				    "FTP LOGIN FAILED FROM %s",
1397 				    remotehost);
1398 				syslog(LOG_AUTHPRIV | LOG_NOTICE,
1399 				    "FTP LOGIN FAILED FROM %s, %s",
1400 				    remotehost, curname);
1401 			}
1402 			pw = NULL;
1403 			if (login_attempts++ >= 5) {
1404 				syslog(LOG_NOTICE,
1405 				    "repeated login failures from %s",
1406 				    remotehost);
1407 				exit(0);
1408 			}
1409 			return;
1410 		} else {
1411 			BLACKLIST_NOTIFY(BLACKLIST_AUTH_OK, STDIN_FILENO, "Login successful");
1412 		}
1413 	}
1414 	login_attempts = 0;		/* this time successful */
1415 	if (setegid(pw->pw_gid) < 0) {
1416 		reply(550, "Can't set gid.");
1417 		return;
1418 	}
1419 	/* May be overridden by login.conf */
1420 	(void) umask(defumask);
1421 #ifdef	LOGIN_CAP
1422 	if ((lc = login_getpwclass(pw)) != NULL) {
1423 		char	remote_ip[NI_MAXHOST];
1424 
1425 		if (getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
1426 			remote_ip, sizeof(remote_ip) - 1, NULL, 0,
1427 			NI_NUMERICHOST))
1428 				*remote_ip = 0;
1429 		remote_ip[sizeof(remote_ip) - 1] = 0;
1430 		if (!auth_hostok(lc, remotehost, remote_ip)) {
1431 			syslog(LOG_INFO|LOG_AUTH,
1432 			    "FTP LOGIN FAILED (HOST) as %s: permission denied.",
1433 			    pw->pw_name);
1434 			reply(530, "Permission denied.");
1435 			pw = NULL;
1436 			return;
1437 		}
1438 		if (!auth_timeok(lc, time(NULL))) {
1439 			reply(530, "Login not available right now.");
1440 			pw = NULL;
1441 			return;
1442 		}
1443 	}
1444 	setusercontext(lc, pw, 0, LOGIN_SETALL &
1445 		       ~(LOGIN_SETRESOURCES | LOGIN_SETUSER | LOGIN_SETPATH | LOGIN_SETENV));
1446 #else
1447 	setlogin(pw->pw_name);
1448 	(void) initgroups(pw->pw_name, pw->pw_gid);
1449 #endif
1450 
1451 #ifdef USE_PAM
1452 	if (pamh) {
1453 		if ((e = pam_open_session(pamh, 0)) != PAM_SUCCESS) {
1454 			syslog(LOG_ERR, "pam_open_session: %s", pam_strerror(pamh, e));
1455 		} else if ((e = pam_setcred(pamh, PAM_ESTABLISH_CRED)) != PAM_SUCCESS) {
1456 			syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, e));
1457 		}
1458 	}
1459 #endif
1460 
1461 	dochroot =
1462 		checkuser(_PATH_FTPCHROOT, pw->pw_name, 1, &residue, &ecode)
1463 #ifdef	LOGIN_CAP	/* Allow login.conf configuration as well */
1464 		|| login_getcapbool(lc, "ftp-chroot", 0)
1465 #endif
1466 	;
1467 	/*
1468 	 * It is possible that checkuser() failed to open the chroot file.
1469 	 * If this is the case, report that logins are un-available, since we
1470 	 * have no way of checking whether or not the user should be chrooted.
1471 	 * We ignore ENOENT since it is not required that this file be present.
1472 	 */
1473 	if (ecode != 0 && ecode != ENOENT) {
1474 		reply(530, "Login not available right now.");
1475 		return;
1476 	}
1477 	chrootdir = NULL;
1478 
1479 	/* Disable wtmp logging when chrooting. */
1480 	if (dochroot || guest)
1481 		dowtmp = 0;
1482 	if (dowtmp)
1483 		ftpd_logwtmp(wtmpid, pw->pw_name,
1484 		    (struct sockaddr *)&his_addr);
1485 	logged_in = 1;
1486 
1487 #ifdef	LOGIN_CAP
1488 	setusercontext(lc, pw, 0, LOGIN_SETRESOURCES);
1489 #endif
1490 
1491 	if (guest && stats && statfd < 0) {
1492 #ifdef VIRTUAL_HOSTING
1493 		statfd = open(thishost->statfile, O_WRONLY|O_APPEND);
1494 #else
1495 		statfd = open(_PATH_FTPDSTATFILE, O_WRONLY|O_APPEND);
1496 #endif
1497 		if (statfd < 0)
1498 			stats = 0;
1499 	}
1500 
1501 	/*
1502 	 * For a chrooted local user,
1503 	 * a) see whether ftpchroot(5) specifies a chroot directory,
1504 	 * b) extract the directory pathname from the line,
1505 	 * c) expand it to the absolute pathname if necessary.
1506 	 */
1507 	if (dochroot && residue &&
1508 	    (chrootdir = strtok(residue, " \t")) != NULL) {
1509 		if (chrootdir[0] != '/')
1510 			asprintf(&chrootdir, "%s/%s", pw->pw_dir, chrootdir);
1511 		else
1512 			chrootdir = strdup(chrootdir); /* make it permanent */
1513 		if (chrootdir == NULL)
1514 			fatalerror("Ran out of memory.");
1515 	}
1516 	if (guest || dochroot) {
1517 		/*
1518 		 * If no chroot directory set yet, use the login directory.
1519 		 * Copy it so it can be modified while pw->pw_dir stays intact.
1520 		 */
1521 		if (chrootdir == NULL &&
1522 		    (chrootdir = strdup(pw->pw_dir)) == NULL)
1523 			fatalerror("Ran out of memory.");
1524 		/*
1525 		 * Check for the "/chroot/./home" syntax,
1526 		 * separate the chroot and home directory pathnames.
1527 		 */
1528 		if ((homedir = strstr(chrootdir, "/./")) != NULL) {
1529 			*(homedir++) = '\0';	/* wipe '/' */
1530 			homedir++;		/* skip '.' */
1531 		} else {
1532 			/*
1533 			 * We MUST do a chdir() after the chroot. Otherwise
1534 			 * the old current directory will be accessible as "."
1535 			 * outside the new root!
1536 			 */
1537 			homedir = "/";
1538 		}
1539 		/*
1540 		 * Finally, do chroot()
1541 		 */
1542 		if (chroot(chrootdir) < 0) {
1543 			reply(550, "Can't change root.");
1544 			goto bad;
1545 		}
1546 		__FreeBSD_libc_enter_restricted_mode();
1547 	} else	/* real user w/o chroot */
1548 		homedir = pw->pw_dir;
1549 	/*
1550 	 * Set euid *before* doing chdir() so
1551 	 * a) the user won't be carried to a directory that he couldn't reach
1552 	 *    on his own due to no permission to upper path components,
1553 	 * b) NFS mounted homedirs w/restrictive permissions will be accessible
1554 	 *    (uid 0 has no root power over NFS if not mapped explicitly.)
1555 	 */
1556 	if (seteuid(pw->pw_uid) < 0) {
1557 		if (guest || dochroot) {
1558 			fatalerror("Can't set uid.");
1559 		} else {
1560 			reply(550, "Can't set uid.");
1561 			goto bad;
1562 		}
1563 	}
1564 	/*
1565 	 * Do not allow the session to live if we're chroot()'ed and chdir()
1566 	 * fails. Otherwise the chroot jail can be escaped.
1567 	 */
1568 	if (chdir(homedir) < 0) {
1569 		if (guest || dochroot) {
1570 			fatalerror("Can't change to base directory.");
1571 		} else {
1572 			if (chdir("/") < 0) {
1573 				reply(550, "Root is inaccessible.");
1574 				goto bad;
1575 			}
1576 			lreply(230, "No directory! Logging in with home=/.");
1577 		}
1578 	}
1579 
1580 	/*
1581 	 * Display a login message, if it exists.
1582 	 * N.B. reply(230,) must follow the message.
1583 	 */
1584 #ifdef VIRTUAL_HOSTING
1585 	fd = fopen(thishost->loginmsg, "r");
1586 #else
1587 	fd = fopen(_PATH_FTPLOGINMESG, "r");
1588 #endif
1589 	if (fd != NULL) {
1590 		char *cp, line[LINE_MAX];
1591 
1592 		while (fgets(line, sizeof(line), fd) != NULL) {
1593 			if ((cp = strchr(line, '\n')) != NULL)
1594 				*cp = '\0';
1595 			lreply(230, "%s", line);
1596 		}
1597 		(void) fflush(stdout);
1598 		(void) fclose(fd);
1599 	}
1600 	if (guest) {
1601 		if (ident != NULL)
1602 			free(ident);
1603 		ident = strdup(passwd);
1604 		if (ident == NULL)
1605 			fatalerror("Ran out of memory.");
1606 
1607 		reply(230, "Guest login ok, access restrictions apply.");
1608 #ifdef SETPROCTITLE
1609 #ifdef VIRTUAL_HOSTING
1610 		if (thishost != firsthost)
1611 			snprintf(proctitle, sizeof(proctitle),
1612 				 "%s: anonymous(%s)/%s", remotehost, hostname,
1613 				 passwd);
1614 		else
1615 #endif
1616 			snprintf(proctitle, sizeof(proctitle),
1617 				 "%s: anonymous/%s", remotehost, passwd);
1618 		setproctitle("%s", proctitle);
1619 #endif /* SETPROCTITLE */
1620 		if (logging)
1621 			syslog(LOG_INFO, "ANONYMOUS FTP LOGIN FROM %s, %s",
1622 			    remotehost, passwd);
1623 	} else {
1624 		if (dochroot)
1625 			reply(230, "User %s logged in, "
1626 				   "access restrictions apply.", pw->pw_name);
1627 		else
1628 			reply(230, "User %s logged in.", pw->pw_name);
1629 
1630 #ifdef SETPROCTITLE
1631 		snprintf(proctitle, sizeof(proctitle),
1632 			 "%s: user/%s", remotehost, pw->pw_name);
1633 		setproctitle("%s", proctitle);
1634 #endif /* SETPROCTITLE */
1635 		if (logging)
1636 			syslog(LOG_INFO, "FTP LOGIN FROM %s as %s",
1637 			    remotehost, pw->pw_name);
1638 	}
1639 	if (logging && (guest || dochroot))
1640 		syslog(LOG_INFO, "session root changed to %s", chrootdir);
1641 #ifdef	LOGIN_CAP
1642 	login_close(lc);
1643 #endif
1644 	if (residue)
1645 		free(residue);
1646 	return;
1647 bad:
1648 	/* Forget all about it... */
1649 #ifdef	LOGIN_CAP
1650 	login_close(lc);
1651 #endif
1652 	if (residue)
1653 		free(residue);
1654 	end_login();
1655 }
1656 
1657 void
1658 retrieve(char *cmd, char *name)
1659 {
1660 	FILE *fin, *dout;
1661 	struct stat st;
1662 	int (*closefunc)(FILE *);
1663 	time_t start;
1664 	char line[BUFSIZ];
1665 
1666 	if (cmd == 0) {
1667 		fin = fopen(name, "r"), closefunc = fclose;
1668 		st.st_size = 0;
1669 	} else {
1670 		(void) snprintf(line, sizeof(line), cmd, name);
1671 		name = line;
1672 		fin = ftpd_popen(line, "r"), closefunc = ftpd_pclose;
1673 		st.st_size = -1;
1674 		st.st_blksize = BUFSIZ;
1675 	}
1676 	if (fin == NULL) {
1677 		if (errno != 0) {
1678 			perror_reply(550, name);
1679 			if (cmd == 0) {
1680 				LOGCMD("get", name);
1681 			}
1682 		}
1683 		return;
1684 	}
1685 	byte_count = -1;
1686 	if (cmd == 0) {
1687 		if (fstat(fileno(fin), &st) < 0) {
1688 			perror_reply(550, name);
1689 			goto done;
1690 		}
1691 		if (!S_ISREG(st.st_mode)) {
1692 			/*
1693 			 * Never sending a raw directory is a workaround
1694 			 * for buggy clients that will attempt to RETR
1695 			 * a directory before listing it, e.g., Mozilla.
1696 			 * Preventing a guest from getting irregular files
1697 			 * is a simple security measure.
1698 			 */
1699 			if (S_ISDIR(st.st_mode) || guest) {
1700 				reply(550, "%s: not a plain file.", name);
1701 				goto done;
1702 			}
1703 			st.st_size = -1;
1704 			/* st.st_blksize is set for all descriptor types */
1705 		}
1706 	}
1707 	if (restart_point) {
1708 		if (type == TYPE_A) {
1709 			off_t i, n;
1710 			int c;
1711 
1712 			n = restart_point;
1713 			i = 0;
1714 			while (i++ < n) {
1715 				if ((c=getc(fin)) == EOF) {
1716 					perror_reply(550, name);
1717 					goto done;
1718 				}
1719 				if (c == '\n')
1720 					i++;
1721 			}
1722 		} else if (lseek(fileno(fin), restart_point, L_SET) < 0) {
1723 			perror_reply(550, name);
1724 			goto done;
1725 		}
1726 	}
1727 	dout = dataconn(name, st.st_size, "w");
1728 	if (dout == NULL)
1729 		goto done;
1730 	time(&start);
1731 	send_data(fin, dout, st.st_blksize, st.st_size,
1732 		  restart_point == 0 && cmd == 0 && S_ISREG(st.st_mode));
1733 	if (cmd == 0 && guest && stats && byte_count > 0)
1734 		logxfer(name, byte_count, start);
1735 	(void) fclose(dout);
1736 	data = -1;
1737 	pdata = -1;
1738 done:
1739 	if (cmd == 0)
1740 		LOGBYTES("get", name, byte_count);
1741 	(*closefunc)(fin);
1742 }
1743 
1744 void
1745 store(char *name, char *mode, int unique)
1746 {
1747 	int fd;
1748 	FILE *fout, *din;
1749 	int (*closefunc)(FILE *);
1750 
1751 	if (*mode == 'a') {		/* APPE */
1752 		if (unique) {
1753 			/* Programming error */
1754 			syslog(LOG_ERR, "Internal: unique flag to APPE");
1755 			unique = 0;
1756 		}
1757 		if (guest && noguestmod) {
1758 			reply(550, "Appending to existing file denied.");
1759 			goto err;
1760 		}
1761 		restart_point = 0;	/* not affected by preceding REST */
1762 	}
1763 	if (unique)			/* STOU overrides REST */
1764 		restart_point = 0;
1765 	if (guest && noguestmod) {
1766 		if (restart_point) {	/* guest STOR w/REST */
1767 			reply(550, "Modifying existing file denied.");
1768 			goto err;
1769 		} else			/* treat guest STOR as STOU */
1770 			unique = 1;
1771 	}
1772 
1773 	if (restart_point)
1774 		mode = "r+";	/* so ASCII manual seek can work */
1775 	if (unique) {
1776 		if ((fd = guniquefd(name, &name)) < 0)
1777 			goto err;
1778 		fout = fdopen(fd, mode);
1779 	} else
1780 		fout = fopen(name, mode);
1781 	closefunc = fclose;
1782 	if (fout == NULL) {
1783 		perror_reply(553, name);
1784 		goto err;
1785 	}
1786 	byte_count = -1;
1787 	if (restart_point) {
1788 		if (type == TYPE_A) {
1789 			off_t i, n;
1790 			int c;
1791 
1792 			n = restart_point;
1793 			i = 0;
1794 			while (i++ < n) {
1795 				if ((c=getc(fout)) == EOF) {
1796 					perror_reply(550, name);
1797 					goto done;
1798 				}
1799 				if (c == '\n')
1800 					i++;
1801 			}
1802 			/*
1803 			 * We must do this seek to "current" position
1804 			 * because we are changing from reading to
1805 			 * writing.
1806 			 */
1807 			if (fseeko(fout, 0, SEEK_CUR) < 0) {
1808 				perror_reply(550, name);
1809 				goto done;
1810 			}
1811 		} else if (lseek(fileno(fout), restart_point, L_SET) < 0) {
1812 			perror_reply(550, name);
1813 			goto done;
1814 		}
1815 	}
1816 	din = dataconn(name, -1, "r");
1817 	if (din == NULL)
1818 		goto done;
1819 	if (receive_data(din, fout) == 0) {
1820 		if (unique)
1821 			reply(226, "Transfer complete (unique file name:%s).",
1822 			    name);
1823 		else
1824 			reply(226, "Transfer complete.");
1825 	}
1826 	(void) fclose(din);
1827 	data = -1;
1828 	pdata = -1;
1829 done:
1830 	LOGBYTES(*mode == 'a' ? "append" : "put", name, byte_count);
1831 	(*closefunc)(fout);
1832 	return;
1833 err:
1834 	LOGCMD(*mode == 'a' ? "append" : "put" , name);
1835 	return;
1836 }
1837 
1838 static FILE *
1839 getdatasock(char *mode)
1840 {
1841 	int on = 1, s, t, tries;
1842 
1843 	if (data >= 0)
1844 		return (fdopen(data, mode));
1845 
1846 	s = socket(data_dest.su_family, SOCK_STREAM, 0);
1847 	if (s < 0)
1848 		goto bad;
1849 	if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
1850 		syslog(LOG_WARNING, "data setsockopt (SO_REUSEADDR): %m");
1851 	/* anchor socket to avoid multi-homing problems */
1852 	data_source = ctrl_addr;
1853 	data_source.su_port = htons(dataport);
1854 	(void) seteuid(0);
1855 	for (tries = 1; ; tries++) {
1856 		/*
1857 		 * We should loop here since it's possible that
1858 		 * another ftpd instance has passed this point and is
1859 		 * trying to open a data connection in active mode now.
1860 		 * Until the other connection is opened, we'll be getting
1861 		 * EADDRINUSE because no SOCK_STREAM sockets in the system
1862 		 * can share both local and remote addresses, localIP:20
1863 		 * and *:* in this case.
1864 		 */
1865 		if (bind(s, (struct sockaddr *)&data_source,
1866 		    data_source.su_len) >= 0)
1867 			break;
1868 		if (errno != EADDRINUSE || tries > 10)
1869 			goto bad;
1870 		sleep(tries);
1871 	}
1872 	(void) seteuid(pw->pw_uid);
1873 #ifdef IP_TOS
1874 	if (data_source.su_family == AF_INET)
1875       {
1876 	on = IPTOS_THROUGHPUT;
1877 	if (setsockopt(s, IPPROTO_IP, IP_TOS, &on, sizeof(int)) < 0)
1878 		syslog(LOG_WARNING, "data setsockopt (IP_TOS): %m");
1879       }
1880 #endif
1881 #ifdef TCP_NOPUSH
1882 	/*
1883 	 * Turn off push flag to keep sender TCP from sending short packets
1884 	 * at the boundaries of each write().
1885 	 */
1886 	on = 1;
1887 	if (setsockopt(s, IPPROTO_TCP, TCP_NOPUSH, &on, sizeof on) < 0)
1888 		syslog(LOG_WARNING, "data setsockopt (TCP_NOPUSH): %m");
1889 #endif
1890 	return (fdopen(s, mode));
1891 bad:
1892 	/* Return the real value of errno (close may change it) */
1893 	t = errno;
1894 	(void) seteuid(pw->pw_uid);
1895 	(void) close(s);
1896 	errno = t;
1897 	return (NULL);
1898 }
1899 
1900 static FILE *
1901 dataconn(char *name, off_t size, char *mode)
1902 {
1903 	char sizebuf[32];
1904 	FILE *file;
1905 	int retry = 0, tos, conerrno;
1906 
1907 	file_size = size;
1908 	byte_count = 0;
1909 	if (size != -1)
1910 		(void) snprintf(sizebuf, sizeof(sizebuf),
1911 				" (%jd bytes)", (intmax_t)size);
1912 	else
1913 		*sizebuf = '\0';
1914 	if (pdata >= 0) {
1915 		union sockunion from;
1916 		socklen_t fromlen = ctrl_addr.su_len;
1917 		int flags, s;
1918 		struct timeval timeout;
1919 		fd_set set;
1920 
1921 		FD_ZERO(&set);
1922 		FD_SET(pdata, &set);
1923 
1924 		timeout.tv_usec = 0;
1925 		timeout.tv_sec = 120;
1926 
1927 		/*
1928 		 * Granted a socket is in the blocking I/O mode,
1929 		 * accept() will block after a successful select()
1930 		 * if the selected connection dies in between.
1931 		 * Therefore set the non-blocking I/O flag here.
1932 		 */
1933 		if ((flags = fcntl(pdata, F_GETFL, 0)) == -1 ||
1934 		    fcntl(pdata, F_SETFL, flags | O_NONBLOCK) == -1)
1935 			goto pdata_err;
1936 		if (select(pdata+1, &set, NULL, NULL, &timeout) <= 0 ||
1937 		    (s = accept(pdata, (struct sockaddr *) &from, &fromlen)) < 0)
1938 			goto pdata_err;
1939 		(void) close(pdata);
1940 		pdata = s;
1941 		/*
1942 		 * Unset the inherited non-blocking I/O flag
1943 		 * on the child socket so stdio can work on it.
1944 		 */
1945 		if ((flags = fcntl(pdata, F_GETFL, 0)) == -1 ||
1946 		    fcntl(pdata, F_SETFL, flags & ~O_NONBLOCK) == -1)
1947 			goto pdata_err;
1948 #ifdef IP_TOS
1949 		if (from.su_family == AF_INET)
1950 	      {
1951 		tos = IPTOS_THROUGHPUT;
1952 		if (setsockopt(s, IPPROTO_IP, IP_TOS, &tos, sizeof(int)) < 0)
1953 			syslog(LOG_WARNING, "pdata setsockopt (IP_TOS): %m");
1954 	      }
1955 #endif
1956 		reply(150, "Opening %s mode data connection for '%s'%s.",
1957 		     type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
1958 		return (fdopen(pdata, mode));
1959 pdata_err:
1960 		reply(425, "Can't open data connection.");
1961 		(void) close(pdata);
1962 		pdata = -1;
1963 		return (NULL);
1964 	}
1965 	if (data >= 0) {
1966 		reply(125, "Using existing data connection for '%s'%s.",
1967 		    name, sizebuf);
1968 		usedefault = 1;
1969 		return (fdopen(data, mode));
1970 	}
1971 	if (usedefault)
1972 		data_dest = his_addr;
1973 	usedefault = 1;
1974 	do {
1975 		file = getdatasock(mode);
1976 		if (file == NULL) {
1977 			char hostbuf[NI_MAXHOST], portbuf[NI_MAXSERV];
1978 
1979 			if (getnameinfo((struct sockaddr *)&data_source,
1980 				data_source.su_len,
1981 				hostbuf, sizeof(hostbuf) - 1,
1982 				portbuf, sizeof(portbuf) - 1,
1983 				NI_NUMERICHOST|NI_NUMERICSERV))
1984 					*hostbuf = *portbuf = 0;
1985 			hostbuf[sizeof(hostbuf) - 1] = 0;
1986 			portbuf[sizeof(portbuf) - 1] = 0;
1987 			reply(425, "Can't create data socket (%s,%s): %s.",
1988 				hostbuf, portbuf, strerror(errno));
1989 			return (NULL);
1990 		}
1991 		data = fileno(file);
1992 		conerrno = 0;
1993 		if (connect(data, (struct sockaddr *)&data_dest,
1994 		    data_dest.su_len) == 0)
1995 			break;
1996 		conerrno = errno;
1997 		(void) fclose(file);
1998 		data = -1;
1999 		if (conerrno == EADDRINUSE) {
2000 			sleep(swaitint);
2001 			retry += swaitint;
2002 		} else {
2003 			break;
2004 		}
2005 	} while (retry <= swaitmax);
2006 	if (conerrno != 0) {
2007 		reply(425, "Can't build data connection: %s.",
2008 			   strerror(conerrno));
2009 		return (NULL);
2010 	}
2011 	reply(150, "Opening %s mode data connection for '%s'%s.",
2012 	     type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
2013 	return (file);
2014 }
2015 
2016 /*
2017  * A helper macro to avoid code duplication
2018  * in send_data() and receive_data().
2019  *
2020  * XXX We have to block SIGURG during putc() because BSD stdio
2021  * is unable to restart interrupted write operations and hence
2022  * the entire buffer contents will be lost as soon as a write()
2023  * call indicates EINTR to stdio.
2024  */
2025 #define FTPD_PUTC(ch, file, label)					\
2026 	do {								\
2027 		int ret;						\
2028 									\
2029 		do {							\
2030 			START_UNSAFE;					\
2031 			ret = putc((ch), (file));			\
2032 			END_UNSAFE;					\
2033 			CHECKOOB(return (-1))				\
2034 			else if (ferror(file))				\
2035 				goto label;				\
2036 			clearerr(file);					\
2037 		} while (ret == EOF);					\
2038 	} while (0)
2039 
2040 /*
2041  * Transfer the contents of "instr" to "outstr" peer using the appropriate
2042  * encapsulation of the data subject to Mode, Structure, and Type.
2043  *
2044  * NB: Form isn't handled.
2045  */
2046 static int
2047 send_data(FILE *instr, FILE *outstr, size_t blksize, off_t filesize, int isreg)
2048 {
2049 	int c, cp, filefd, netfd;
2050 	char *buf;
2051 
2052 	STARTXFER;
2053 
2054 	switch (type) {
2055 
2056 	case TYPE_A:
2057 		cp = EOF;
2058 		for (;;) {
2059 			c = getc(instr);
2060 			CHECKOOB(return (-1))
2061 			else if (c == EOF && ferror(instr))
2062 				goto file_err;
2063 			if (c == EOF) {
2064 				if (ferror(instr)) {	/* resume after OOB */
2065 					clearerr(instr);
2066 					continue;
2067 				}
2068 				if (feof(instr))	/* EOF */
2069 					break;
2070 				syslog(LOG_ERR, "Internal: impossible condition"
2071 						" on file after getc()");
2072 				goto file_err;
2073 			}
2074 			if (c == '\n' && cp != '\r') {
2075 				FTPD_PUTC('\r', outstr, data_err);
2076 				byte_count++;
2077 			}
2078 			FTPD_PUTC(c, outstr, data_err);
2079 			byte_count++;
2080 			cp = c;
2081 		}
2082 #ifdef notyet	/* BSD stdio isn't ready for that */
2083 		while (fflush(outstr) == EOF) {
2084 			CHECKOOB(return (-1))
2085 			else
2086 				goto data_err;
2087 			clearerr(outstr);
2088 		}
2089 		ENDXFER;
2090 #else
2091 		ENDXFER;
2092 		if (fflush(outstr) == EOF)
2093 			goto data_err;
2094 #endif
2095 		reply(226, "Transfer complete.");
2096 		return (0);
2097 
2098 	case TYPE_I:
2099 	case TYPE_L:
2100 		/*
2101 		 * isreg is only set if we are not doing restart and we
2102 		 * are sending a regular file
2103 		 */
2104 		netfd = fileno(outstr);
2105 		filefd = fileno(instr);
2106 
2107 		if (isreg) {
2108 			char *msg = "Transfer complete.";
2109 			off_t cnt, offset;
2110 			int err;
2111 
2112 			cnt = offset = 0;
2113 
2114 			while (filesize > 0) {
2115 				err = sendfile(filefd, netfd, offset, 0,
2116 					       NULL, &cnt, 0);
2117 				/*
2118 				 * Calculate byte_count before OOB processing.
2119 				 * It can be used in myoob() later.
2120 				 */
2121 				byte_count += cnt;
2122 				offset += cnt;
2123 				filesize -= cnt;
2124 				CHECKOOB(return (-1))
2125 				else if (err == -1) {
2126 					if (errno != EINTR &&
2127 					    cnt == 0 && offset == 0)
2128 						goto oldway;
2129 					goto data_err;
2130 				}
2131 				if (err == -1)	/* resume after OOB */
2132 					continue;
2133 				/*
2134 				 * We hit the EOF prematurely.
2135 				 * Perhaps the file was externally truncated.
2136 				 */
2137 				if (cnt == 0) {
2138 					msg = "Transfer finished due to "
2139 					      "premature end of file.";
2140 					break;
2141 				}
2142 			}
2143 			ENDXFER;
2144 			reply(226, "%s", msg);
2145 			return (0);
2146 		}
2147 
2148 oldway:
2149 		if ((buf = malloc(blksize)) == NULL) {
2150 			ENDXFER;
2151 			reply(451, "Ran out of memory.");
2152 			return (-1);
2153 		}
2154 
2155 		for (;;) {
2156 			int cnt, len;
2157 			char *bp;
2158 
2159 			cnt = read(filefd, buf, blksize);
2160 			CHECKOOB(free(buf); return (-1))
2161 			else if (cnt < 0) {
2162 				free(buf);
2163 				goto file_err;
2164 			}
2165 			if (cnt < 0)	/* resume after OOB */
2166 				continue;
2167 			if (cnt == 0)	/* EOF */
2168 				break;
2169 			for (len = cnt, bp = buf; len > 0;) {
2170 				cnt = write(netfd, bp, len);
2171 				CHECKOOB(free(buf); return (-1))
2172 				else if (cnt < 0) {
2173 					free(buf);
2174 					goto data_err;
2175 				}
2176 				if (cnt <= 0)
2177 					continue;
2178 				len -= cnt;
2179 				bp += cnt;
2180 				byte_count += cnt;
2181 			}
2182 		}
2183 		ENDXFER;
2184 		free(buf);
2185 		reply(226, "Transfer complete.");
2186 		return (0);
2187 	default:
2188 		ENDXFER;
2189 		reply(550, "Unimplemented TYPE %d in send_data.", type);
2190 		return (-1);
2191 	}
2192 
2193 data_err:
2194 	ENDXFER;
2195 	perror_reply(426, "Data connection");
2196 	return (-1);
2197 
2198 file_err:
2199 	ENDXFER;
2200 	perror_reply(551, "Error on input file");
2201 	return (-1);
2202 }
2203 
2204 /*
2205  * Transfer data from peer to "outstr" using the appropriate encapulation of
2206  * the data subject to Mode, Structure, and Type.
2207  *
2208  * N.B.: Form isn't handled.
2209  */
2210 static int
2211 receive_data(FILE *instr, FILE *outstr)
2212 {
2213 	int c, cp;
2214 	int bare_lfs = 0;
2215 
2216 	STARTXFER;
2217 
2218 	switch (type) {
2219 
2220 	case TYPE_I:
2221 	case TYPE_L:
2222 		for (;;) {
2223 			int cnt, len;
2224 			char *bp;
2225 			char buf[BUFSIZ];
2226 
2227 			cnt = read(fileno(instr), buf, sizeof(buf));
2228 			CHECKOOB(return (-1))
2229 			else if (cnt < 0)
2230 				goto data_err;
2231 			if (cnt < 0)	/* resume after OOB */
2232 				continue;
2233 			if (cnt == 0)	/* EOF */
2234 				break;
2235 			for (len = cnt, bp = buf; len > 0;) {
2236 				cnt = write(fileno(outstr), bp, len);
2237 				CHECKOOB(return (-1))
2238 				else if (cnt < 0)
2239 					goto file_err;
2240 				if (cnt <= 0)
2241 					continue;
2242 				len -= cnt;
2243 				bp += cnt;
2244 				byte_count += cnt;
2245 			}
2246 		}
2247 		ENDXFER;
2248 		return (0);
2249 
2250 	case TYPE_E:
2251 		ENDXFER;
2252 		reply(553, "TYPE E not implemented.");
2253 		return (-1);
2254 
2255 	case TYPE_A:
2256 		cp = EOF;
2257 		for (;;) {
2258 			c = getc(instr);
2259 			CHECKOOB(return (-1))
2260 			else if (c == EOF && ferror(instr))
2261 				goto data_err;
2262 			if (c == EOF && ferror(instr)) { /* resume after OOB */
2263 				clearerr(instr);
2264 				continue;
2265 			}
2266 
2267 			if (cp == '\r') {
2268 				if (c != '\n')
2269 					FTPD_PUTC('\r', outstr, file_err);
2270 			} else
2271 				if (c == '\n')
2272 					bare_lfs++;
2273 			if (c == '\r') {
2274 				byte_count++;
2275 				cp = c;
2276 				continue;
2277 			}
2278 
2279 			/* Check for EOF here in order not to lose last \r. */
2280 			if (c == EOF) {
2281 				if (feof(instr))	/* EOF */
2282 					break;
2283 				syslog(LOG_ERR, "Internal: impossible condition"
2284 						" on data stream after getc()");
2285 				goto data_err;
2286 			}
2287 
2288 			byte_count++;
2289 			FTPD_PUTC(c, outstr, file_err);
2290 			cp = c;
2291 		}
2292 #ifdef notyet	/* BSD stdio isn't ready for that */
2293 		while (fflush(outstr) == EOF) {
2294 			CHECKOOB(return (-1))
2295 			else
2296 				goto file_err;
2297 			clearerr(outstr);
2298 		}
2299 		ENDXFER;
2300 #else
2301 		ENDXFER;
2302 		if (fflush(outstr) == EOF)
2303 			goto file_err;
2304 #endif
2305 		if (bare_lfs) {
2306 			lreply(226,
2307 		"WARNING! %d bare linefeeds received in ASCII mode.",
2308 			    bare_lfs);
2309 		(void)printf("   File may not have transferred correctly.\r\n");
2310 		}
2311 		return (0);
2312 	default:
2313 		ENDXFER;
2314 		reply(550, "Unimplemented TYPE %d in receive_data.", type);
2315 		return (-1);
2316 	}
2317 
2318 data_err:
2319 	ENDXFER;
2320 	perror_reply(426, "Data connection");
2321 	return (-1);
2322 
2323 file_err:
2324 	ENDXFER;
2325 	perror_reply(452, "Error writing to file");
2326 	return (-1);
2327 }
2328 
2329 void
2330 statfilecmd(char *filename)
2331 {
2332 	FILE *fin;
2333 	int atstart;
2334 	int c, code;
2335 	char line[LINE_MAX];
2336 	struct stat st;
2337 
2338 	code = lstat(filename, &st) == 0 && S_ISDIR(st.st_mode) ? 212 : 213;
2339 	(void)snprintf(line, sizeof(line), _PATH_LS " -lgA %s", filename);
2340 	fin = ftpd_popen(line, "r");
2341 	if (fin == NULL) {
2342 		perror_reply(551, filename);
2343 		return;
2344 	}
2345 	lreply(code, "Status of %s:", filename);
2346 	atstart = 1;
2347 	while ((c = getc(fin)) != EOF) {
2348 		if (c == '\n') {
2349 			if (ferror(stdout)){
2350 				perror_reply(421, "Control connection");
2351 				(void) ftpd_pclose(fin);
2352 				dologout(1);
2353 				/* NOTREACHED */
2354 			}
2355 			if (ferror(fin)) {
2356 				perror_reply(551, filename);
2357 				(void) ftpd_pclose(fin);
2358 				return;
2359 			}
2360 			(void) putc('\r', stdout);
2361 		}
2362 		/*
2363 		 * RFC 959 says neutral text should be prepended before
2364 		 * a leading 3-digit number followed by whitespace, but
2365 		 * many ftp clients can be confused by any leading digits,
2366 		 * as a matter of fact.
2367 		 */
2368 		if (atstart && isdigit(c))
2369 			(void) putc(' ', stdout);
2370 		(void) putc(c, stdout);
2371 		atstart = (c == '\n');
2372 	}
2373 	(void) ftpd_pclose(fin);
2374 	reply(code, "End of status.");
2375 }
2376 
2377 void
2378 statcmd(void)
2379 {
2380 	union sockunion *su;
2381 	u_char *a, *p;
2382 	char hname[NI_MAXHOST];
2383 	int ispassive;
2384 
2385 	if (hostinfo) {
2386 		lreply(211, "%s FTP server status:", hostname);
2387 		printf("     %s\r\n", version);
2388 	} else
2389 		lreply(211, "FTP server status:");
2390 	printf("     Connected to %s", remotehost);
2391 	if (!getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
2392 			 hname, sizeof(hname) - 1, NULL, 0, NI_NUMERICHOST)) {
2393 		hname[sizeof(hname) - 1] = 0;
2394 		if (strcmp(hname, remotehost) != 0)
2395 			printf(" (%s)", hname);
2396 	}
2397 	printf("\r\n");
2398 	if (logged_in) {
2399 		if (guest)
2400 			printf("     Logged in anonymously\r\n");
2401 		else
2402 			printf("     Logged in as %s\r\n", pw->pw_name);
2403 	} else if (askpasswd)
2404 		printf("     Waiting for password\r\n");
2405 	else
2406 		printf("     Waiting for user name\r\n");
2407 	printf("     TYPE: %s", typenames[type]);
2408 	if (type == TYPE_A || type == TYPE_E)
2409 		printf(", FORM: %s", formnames[form]);
2410 	if (type == TYPE_L)
2411 #if CHAR_BIT == 8
2412 		printf(" %d", CHAR_BIT);
2413 #else
2414 		printf(" %d", bytesize);	/* need definition! */
2415 #endif
2416 	printf("; STRUcture: %s; transfer MODE: %s\r\n",
2417 	    strunames[stru], modenames[mode]);
2418 	if (data != -1)
2419 		printf("     Data connection open\r\n");
2420 	else if (pdata != -1) {
2421 		ispassive = 1;
2422 		su = &pasv_addr;
2423 		goto printaddr;
2424 	} else if (usedefault == 0) {
2425 		ispassive = 0;
2426 		su = &data_dest;
2427 printaddr:
2428 #define UC(b) (((int) b) & 0xff)
2429 		if (epsvall) {
2430 			printf("     EPSV only mode (EPSV ALL)\r\n");
2431 			goto epsvonly;
2432 		}
2433 
2434 		/* PORT/PASV */
2435 		if (su->su_family == AF_INET) {
2436 			a = (u_char *) &su->su_sin.sin_addr;
2437 			p = (u_char *) &su->su_sin.sin_port;
2438 			printf("     %s (%d,%d,%d,%d,%d,%d)\r\n",
2439 				ispassive ? "PASV" : "PORT",
2440 				UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
2441 				UC(p[0]), UC(p[1]));
2442 		}
2443 
2444 		/* LPRT/LPSV */
2445 	    {
2446 		int alen, af, i;
2447 
2448 		switch (su->su_family) {
2449 		case AF_INET:
2450 			a = (u_char *) &su->su_sin.sin_addr;
2451 			p = (u_char *) &su->su_sin.sin_port;
2452 			alen = sizeof(su->su_sin.sin_addr);
2453 			af = 4;
2454 			break;
2455 		case AF_INET6:
2456 			a = (u_char *) &su->su_sin6.sin6_addr;
2457 			p = (u_char *) &su->su_sin6.sin6_port;
2458 			alen = sizeof(su->su_sin6.sin6_addr);
2459 			af = 6;
2460 			break;
2461 		default:
2462 			af = 0;
2463 			break;
2464 		}
2465 		if (af) {
2466 			printf("     %s (%d,%d,", ispassive ? "LPSV" : "LPRT",
2467 				af, alen);
2468 			for (i = 0; i < alen; i++)
2469 				printf("%d,", UC(a[i]));
2470 			printf("%d,%d,%d)\r\n", 2, UC(p[0]), UC(p[1]));
2471 		}
2472 	    }
2473 
2474 epsvonly:;
2475 		/* EPRT/EPSV */
2476 	    {
2477 		int af;
2478 
2479 		switch (su->su_family) {
2480 		case AF_INET:
2481 			af = 1;
2482 			break;
2483 		case AF_INET6:
2484 			af = 2;
2485 			break;
2486 		default:
2487 			af = 0;
2488 			break;
2489 		}
2490 		if (af) {
2491 			union sockunion tmp;
2492 
2493 			tmp = *su;
2494 			if (tmp.su_family == AF_INET6)
2495 				tmp.su_sin6.sin6_scope_id = 0;
2496 			if (!getnameinfo((struct sockaddr *)&tmp, tmp.su_len,
2497 					hname, sizeof(hname) - 1, NULL, 0,
2498 					NI_NUMERICHOST)) {
2499 				hname[sizeof(hname) - 1] = 0;
2500 				printf("     %s |%d|%s|%d|\r\n",
2501 					ispassive ? "EPSV" : "EPRT",
2502 					af, hname, htons(tmp.su_port));
2503 			}
2504 		}
2505 	    }
2506 #undef UC
2507 	} else
2508 		printf("     No data connection\r\n");
2509 	reply(211, "End of status.");
2510 }
2511 
2512 void
2513 fatalerror(char *s)
2514 {
2515 
2516 	reply(451, "Error in server: %s", s);
2517 	reply(221, "Closing connection due to server error.");
2518 	dologout(0);
2519 	/* NOTREACHED */
2520 }
2521 
2522 void
2523 reply(int n, const char *fmt, ...)
2524 {
2525 	va_list ap;
2526 
2527 	(void)printf("%d ", n);
2528 	va_start(ap, fmt);
2529 	(void)vprintf(fmt, ap);
2530 	va_end(ap);
2531 	(void)printf("\r\n");
2532 	(void)fflush(stdout);
2533 	if (ftpdebug) {
2534 		syslog(LOG_DEBUG, "<--- %d ", n);
2535 		va_start(ap, fmt);
2536 		vsyslog(LOG_DEBUG, fmt, ap);
2537 		va_end(ap);
2538 	}
2539 }
2540 
2541 void
2542 lreply(int n, const char *fmt, ...)
2543 {
2544 	va_list ap;
2545 
2546 	(void)printf("%d- ", n);
2547 	va_start(ap, fmt);
2548 	(void)vprintf(fmt, ap);
2549 	va_end(ap);
2550 	(void)printf("\r\n");
2551 	(void)fflush(stdout);
2552 	if (ftpdebug) {
2553 		syslog(LOG_DEBUG, "<--- %d- ", n);
2554 		va_start(ap, fmt);
2555 		vsyslog(LOG_DEBUG, fmt, ap);
2556 		va_end(ap);
2557 	}
2558 }
2559 
2560 static void
2561 ack(char *s)
2562 {
2563 
2564 	reply(250, "%s command successful.", s);
2565 }
2566 
2567 void
2568 nack(char *s)
2569 {
2570 
2571 	reply(502, "%s command not implemented.", s);
2572 }
2573 
2574 /* ARGSUSED */
2575 void
2576 yyerror(char *s)
2577 {
2578 	char *cp;
2579 
2580 	if ((cp = strchr(cbuf,'\n')))
2581 		*cp = '\0';
2582 	reply(500, "%s: command not understood.", cbuf);
2583 }
2584 
2585 void
2586 delete(char *name)
2587 {
2588 	struct stat st;
2589 
2590 	LOGCMD("delete", name);
2591 	if (lstat(name, &st) < 0) {
2592 		perror_reply(550, name);
2593 		return;
2594 	}
2595 	if (S_ISDIR(st.st_mode)) {
2596 		if (rmdir(name) < 0) {
2597 			perror_reply(550, name);
2598 			return;
2599 		}
2600 		goto done;
2601 	}
2602 	if (guest && noguestmod) {
2603 		reply(550, "Operation not permitted.");
2604 		return;
2605 	}
2606 	if (unlink(name) < 0) {
2607 		perror_reply(550, name);
2608 		return;
2609 	}
2610 done:
2611 	ack("DELE");
2612 }
2613 
2614 void
2615 cwd(char *path)
2616 {
2617 
2618 	if (chdir(path) < 0)
2619 		perror_reply(550, path);
2620 	else
2621 		ack("CWD");
2622 }
2623 
2624 void
2625 makedir(char *name)
2626 {
2627 	char *s;
2628 
2629 	LOGCMD("mkdir", name);
2630 	if (guest && noguestmkd)
2631 		reply(550, "Operation not permitted.");
2632 	else if (mkdir(name, 0777) < 0)
2633 		perror_reply(550, name);
2634 	else {
2635 		if ((s = doublequote(name)) == NULL)
2636 			fatalerror("Ran out of memory.");
2637 		reply(257, "\"%s\" directory created.", s);
2638 		free(s);
2639 	}
2640 }
2641 
2642 void
2643 removedir(char *name)
2644 {
2645 
2646 	LOGCMD("rmdir", name);
2647 	if (rmdir(name) < 0)
2648 		perror_reply(550, name);
2649 	else
2650 		ack("RMD");
2651 }
2652 
2653 void
2654 pwd(void)
2655 {
2656 	char *s, path[MAXPATHLEN + 1];
2657 
2658 	if (getcwd(path, sizeof(path)) == NULL)
2659 		perror_reply(550, "Get current directory");
2660 	else {
2661 		if ((s = doublequote(path)) == NULL)
2662 			fatalerror("Ran out of memory.");
2663 		reply(257, "\"%s\" is current directory.", s);
2664 		free(s);
2665 	}
2666 }
2667 
2668 char *
2669 renamefrom(char *name)
2670 {
2671 	struct stat st;
2672 
2673 	if (guest && noguestmod) {
2674 		reply(550, "Operation not permitted.");
2675 		return (NULL);
2676 	}
2677 	if (lstat(name, &st) < 0) {
2678 		perror_reply(550, name);
2679 		return (NULL);
2680 	}
2681 	reply(350, "File exists, ready for destination name.");
2682 	return (name);
2683 }
2684 
2685 void
2686 renamecmd(char *from, char *to)
2687 {
2688 	struct stat st;
2689 
2690 	LOGCMD2("rename", from, to);
2691 
2692 	if (guest && (stat(to, &st) == 0)) {
2693 		reply(550, "%s: permission denied.", to);
2694 		return;
2695 	}
2696 
2697 	if (rename(from, to) < 0)
2698 		perror_reply(550, "rename");
2699 	else
2700 		ack("RNTO");
2701 }
2702 
2703 static void
2704 dolog(struct sockaddr *who)
2705 {
2706 	char who_name[NI_MAXHOST];
2707 
2708 	realhostname_sa(remotehost, sizeof(remotehost) - 1, who, who->sa_len);
2709 	remotehost[sizeof(remotehost) - 1] = 0;
2710 	if (getnameinfo(who, who->sa_len,
2711 		who_name, sizeof(who_name) - 1, NULL, 0, NI_NUMERICHOST))
2712 			*who_name = 0;
2713 	who_name[sizeof(who_name) - 1] = 0;
2714 
2715 #ifdef SETPROCTITLE
2716 #ifdef VIRTUAL_HOSTING
2717 	if (thishost != firsthost)
2718 		snprintf(proctitle, sizeof(proctitle), "%s: connected (to %s)",
2719 			 remotehost, hostname);
2720 	else
2721 #endif
2722 		snprintf(proctitle, sizeof(proctitle), "%s: connected",
2723 			 remotehost);
2724 	setproctitle("%s", proctitle);
2725 #endif /* SETPROCTITLE */
2726 
2727 	if (logging) {
2728 #ifdef VIRTUAL_HOSTING
2729 		if (thishost != firsthost)
2730 			syslog(LOG_INFO, "connection from %s (%s) to %s",
2731 			       remotehost, who_name, hostname);
2732 		else
2733 #endif
2734 			syslog(LOG_INFO, "connection from %s (%s)",
2735 			       remotehost, who_name);
2736 	}
2737 }
2738 
2739 /*
2740  * Record logout in wtmp file
2741  * and exit with supplied status.
2742  */
2743 void
2744 dologout(int status)
2745 {
2746 
2747 	if (logged_in && dowtmp) {
2748 		(void) seteuid(0);
2749 #ifdef		LOGIN_CAP
2750  	        setusercontext(NULL, getpwuid(0), 0, LOGIN_SETALL & ~(LOGIN_SETLOGIN |
2751 		       LOGIN_SETUSER | LOGIN_SETGROUP | LOGIN_SETPATH |
2752 		       LOGIN_SETENV));
2753 #endif
2754 		ftpd_logwtmp(wtmpid, NULL, NULL);
2755 	}
2756 	/* beware of flushing buffers after a SIGPIPE */
2757 	_exit(status);
2758 }
2759 
2760 static void
2761 sigurg(int signo)
2762 {
2763 
2764 	recvurg = 1;
2765 }
2766 
2767 static void
2768 maskurg(int flag)
2769 {
2770 	int oerrno;
2771 	sigset_t sset;
2772 
2773 	if (!transflag) {
2774 		syslog(LOG_ERR, "Internal: maskurg() while no transfer");
2775 		return;
2776 	}
2777 	oerrno = errno;
2778 	sigemptyset(&sset);
2779 	sigaddset(&sset, SIGURG);
2780 	sigprocmask(flag ? SIG_BLOCK : SIG_UNBLOCK, &sset, NULL);
2781 	errno = oerrno;
2782 }
2783 
2784 static void
2785 flagxfer(int flag)
2786 {
2787 
2788 	if (flag) {
2789 		if (transflag)
2790 			syslog(LOG_ERR, "Internal: flagxfer(1): "
2791 					"transfer already under way");
2792 		transflag = 1;
2793 		maskurg(0);
2794 		recvurg = 0;
2795 	} else {
2796 		if (!transflag)
2797 			syslog(LOG_ERR, "Internal: flagxfer(0): "
2798 					"no active transfer");
2799 		maskurg(1);
2800 		transflag = 0;
2801 	}
2802 }
2803 
2804 /*
2805  * Returns 0 if OK to resume or -1 if abort requested.
2806  */
2807 static int
2808 myoob(void)
2809 {
2810 	char *cp;
2811 	int ret;
2812 
2813 	if (!transflag) {
2814 		syslog(LOG_ERR, "Internal: myoob() while no transfer");
2815 		return (0);
2816 	}
2817 	cp = tmpline;
2818 	ret = get_line(cp, 7, stdin);
2819 	if (ret == -1) {
2820 		reply(221, "You could at least say goodbye.");
2821 		dologout(0);
2822 	} else if (ret == -2) {
2823 		/* Ignore truncated command. */
2824 		return (0);
2825 	}
2826 	upper(cp);
2827 	if (strcmp(cp, "ABOR\r\n") == 0) {
2828 		tmpline[0] = '\0';
2829 		reply(426, "Transfer aborted. Data connection closed.");
2830 		reply(226, "Abort successful.");
2831 		return (-1);
2832 	}
2833 	if (strcmp(cp, "STAT\r\n") == 0) {
2834 		tmpline[0] = '\0';
2835 		if (file_size != -1)
2836 			reply(213, "Status: %jd of %jd bytes transferred.",
2837 				   (intmax_t)byte_count, (intmax_t)file_size);
2838 		else
2839 			reply(213, "Status: %jd bytes transferred.",
2840 				   (intmax_t)byte_count);
2841 	}
2842 	return (0);
2843 }
2844 
2845 /*
2846  * Note: a response of 425 is not mentioned as a possible response to
2847  *	the PASV command in RFC959. However, it has been blessed as
2848  *	a legitimate response by Jon Postel in a telephone conversation
2849  *	with Rick Adams on 25 Jan 89.
2850  */
2851 void
2852 passive(void)
2853 {
2854 	socklen_t len;
2855 	int on;
2856 	char *p, *a;
2857 
2858 	if (pdata >= 0)		/* close old port if one set */
2859 		close(pdata);
2860 
2861 	pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
2862 	if (pdata < 0) {
2863 		perror_reply(425, "Can't open passive connection");
2864 		return;
2865 	}
2866 	on = 1;
2867 	if (setsockopt(pdata, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
2868 		syslog(LOG_WARNING, "pdata setsockopt (SO_REUSEADDR): %m");
2869 
2870 	(void) seteuid(0);
2871 
2872 #ifdef IP_PORTRANGE
2873 	if (ctrl_addr.su_family == AF_INET) {
2874 	    on = restricted_data_ports ? IP_PORTRANGE_HIGH
2875 				       : IP_PORTRANGE_DEFAULT;
2876 
2877 	    if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE,
2878 			    &on, sizeof(on)) < 0)
2879 		    goto pasv_error;
2880 	}
2881 #endif
2882 #ifdef IPV6_PORTRANGE
2883 	if (ctrl_addr.su_family == AF_INET6) {
2884 	    on = restricted_data_ports ? IPV6_PORTRANGE_HIGH
2885 				       : IPV6_PORTRANGE_DEFAULT;
2886 
2887 	    if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE,
2888 			    &on, sizeof(on)) < 0)
2889 		    goto pasv_error;
2890 	}
2891 #endif
2892 
2893 	pasv_addr = ctrl_addr;
2894 	pasv_addr.su_port = 0;
2895 	if (bind(pdata, (struct sockaddr *)&pasv_addr, pasv_addr.su_len) < 0)
2896 		goto pasv_error;
2897 
2898 	(void) seteuid(pw->pw_uid);
2899 
2900 	len = sizeof(pasv_addr);
2901 	if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0)
2902 		goto pasv_error;
2903 	if (listen(pdata, 1) < 0)
2904 		goto pasv_error;
2905 	if (pasv_addr.su_family == AF_INET)
2906 		a = (char *) &pasv_addr.su_sin.sin_addr;
2907 	else if (pasv_addr.su_family == AF_INET6 &&
2908 		 IN6_IS_ADDR_V4MAPPED(&pasv_addr.su_sin6.sin6_addr))
2909 		a = (char *) &pasv_addr.su_sin6.sin6_addr.s6_addr[12];
2910 	else
2911 		goto pasv_error;
2912 
2913 	p = (char *) &pasv_addr.su_port;
2914 
2915 #define UC(b) (((int) b) & 0xff)
2916 
2917 	reply(227, "Entering Passive Mode (%d,%d,%d,%d,%d,%d)", UC(a[0]),
2918 		UC(a[1]), UC(a[2]), UC(a[3]), UC(p[0]), UC(p[1]));
2919 	return;
2920 
2921 pasv_error:
2922 	(void) seteuid(pw->pw_uid);
2923 	(void) close(pdata);
2924 	pdata = -1;
2925 	perror_reply(425, "Can't open passive connection");
2926 	return;
2927 }
2928 
2929 /*
2930  * Long Passive defined in RFC 1639.
2931  *     228 Entering Long Passive Mode
2932  *         (af, hal, h1, h2, h3,..., pal, p1, p2...)
2933  */
2934 
2935 void
2936 long_passive(char *cmd, int pf)
2937 {
2938 	socklen_t len;
2939 	int on;
2940 	char *p, *a;
2941 
2942 	if (pdata >= 0)		/* close old port if one set */
2943 		close(pdata);
2944 
2945 	if (pf != PF_UNSPEC) {
2946 		if (ctrl_addr.su_family != pf) {
2947 			switch (ctrl_addr.su_family) {
2948 			case AF_INET:
2949 				pf = 1;
2950 				break;
2951 			case AF_INET6:
2952 				pf = 2;
2953 				break;
2954 			default:
2955 				pf = 0;
2956 				break;
2957 			}
2958 			/*
2959 			 * XXX
2960 			 * only EPRT/EPSV ready clients will understand this
2961 			 */
2962 			if (strcmp(cmd, "EPSV") == 0 && pf) {
2963 				reply(522, "Network protocol mismatch, "
2964 					"use (%d)", pf);
2965 			} else
2966 				reply(501, "Network protocol mismatch."); /*XXX*/
2967 
2968 			return;
2969 		}
2970 	}
2971 
2972 	pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
2973 	if (pdata < 0) {
2974 		perror_reply(425, "Can't open passive connection");
2975 		return;
2976 	}
2977 	on = 1;
2978 	if (setsockopt(pdata, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
2979 		syslog(LOG_WARNING, "pdata setsockopt (SO_REUSEADDR): %m");
2980 
2981 	(void) seteuid(0);
2982 
2983 	pasv_addr = ctrl_addr;
2984 	pasv_addr.su_port = 0;
2985 	len = pasv_addr.su_len;
2986 
2987 #ifdef IP_PORTRANGE
2988 	if (ctrl_addr.su_family == AF_INET) {
2989 	    on = restricted_data_ports ? IP_PORTRANGE_HIGH
2990 				       : IP_PORTRANGE_DEFAULT;
2991 
2992 	    if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE,
2993 			    &on, sizeof(on)) < 0)
2994 		    goto pasv_error;
2995 	}
2996 #endif
2997 #ifdef IPV6_PORTRANGE
2998 	if (ctrl_addr.su_family == AF_INET6) {
2999 	    on = restricted_data_ports ? IPV6_PORTRANGE_HIGH
3000 				       : IPV6_PORTRANGE_DEFAULT;
3001 
3002 	    if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE,
3003 			    &on, sizeof(on)) < 0)
3004 		    goto pasv_error;
3005 	}
3006 #endif
3007 
3008 	if (bind(pdata, (struct sockaddr *)&pasv_addr, len) < 0)
3009 		goto pasv_error;
3010 
3011 	(void) seteuid(pw->pw_uid);
3012 
3013 	if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0)
3014 		goto pasv_error;
3015 	if (listen(pdata, 1) < 0)
3016 		goto pasv_error;
3017 
3018 #define UC(b) (((int) b) & 0xff)
3019 
3020 	if (strcmp(cmd, "LPSV") == 0) {
3021 		p = (char *)&pasv_addr.su_port;
3022 		switch (pasv_addr.su_family) {
3023 		case AF_INET:
3024 			a = (char *) &pasv_addr.su_sin.sin_addr;
3025 		v4_reply:
3026 			reply(228,
3027 "Entering Long Passive Mode (%d,%d,%d,%d,%d,%d,%d,%d,%d)",
3028 			      4, 4, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
3029 			      2, UC(p[0]), UC(p[1]));
3030 			return;
3031 		case AF_INET6:
3032 			if (IN6_IS_ADDR_V4MAPPED(&pasv_addr.su_sin6.sin6_addr)) {
3033 				a = (char *) &pasv_addr.su_sin6.sin6_addr.s6_addr[12];
3034 				goto v4_reply;
3035 			}
3036 			a = (char *) &pasv_addr.su_sin6.sin6_addr;
3037 			reply(228,
3038 "Entering Long Passive Mode "
3039 "(%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d)",
3040 			      6, 16, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
3041 			      UC(a[4]), UC(a[5]), UC(a[6]), UC(a[7]),
3042 			      UC(a[8]), UC(a[9]), UC(a[10]), UC(a[11]),
3043 			      UC(a[12]), UC(a[13]), UC(a[14]), UC(a[15]),
3044 			      2, UC(p[0]), UC(p[1]));
3045 			return;
3046 		}
3047 	} else if (strcmp(cmd, "EPSV") == 0) {
3048 		switch (pasv_addr.su_family) {
3049 		case AF_INET:
3050 		case AF_INET6:
3051 			reply(229, "Entering Extended Passive Mode (|||%d|)",
3052 				ntohs(pasv_addr.su_port));
3053 			return;
3054 		}
3055 	} else {
3056 		/* more proper error code? */
3057 	}
3058 
3059 pasv_error:
3060 	(void) seteuid(pw->pw_uid);
3061 	(void) close(pdata);
3062 	pdata = -1;
3063 	perror_reply(425, "Can't open passive connection");
3064 	return;
3065 }
3066 
3067 /*
3068  * Generate unique name for file with basename "local"
3069  * and open the file in order to avoid possible races.
3070  * Try "local" first, then "local.1", "local.2" etc, up to "local.99".
3071  * Return descriptor to the file, set "name" to its name.
3072  *
3073  * Generates failure reply on error.
3074  */
3075 static int
3076 guniquefd(char *local, char **name)
3077 {
3078 	static char new[MAXPATHLEN];
3079 	struct stat st;
3080 	char *cp;
3081 	int count;
3082 	int fd;
3083 
3084 	cp = strrchr(local, '/');
3085 	if (cp)
3086 		*cp = '\0';
3087 	if (stat(cp ? local : ".", &st) < 0) {
3088 		perror_reply(553, cp ? local : ".");
3089 		return (-1);
3090 	}
3091 	if (cp) {
3092 		/*
3093 		 * Let not overwrite dirname with counter suffix.
3094 		 * -4 is for /nn\0
3095 		 * In this extreme case dot won't be put in front of suffix.
3096 		 */
3097 		if (strlen(local) > sizeof(new) - 4) {
3098 			reply(553, "Pathname too long.");
3099 			return (-1);
3100 		}
3101 		*cp = '/';
3102 	}
3103 	/* -4 is for the .nn<null> we put on the end below */
3104 	(void) snprintf(new, sizeof(new) - 4, "%s", local);
3105 	cp = new + strlen(new);
3106 	/*
3107 	 * Don't generate dotfile unless requested explicitly.
3108 	 * This covers the case when basename gets truncated off
3109 	 * by buffer size.
3110 	 */
3111 	if (cp > new && cp[-1] != '/')
3112 		*cp++ = '.';
3113 	for (count = 0; count < 100; count++) {
3114 		/* At count 0 try unmodified name */
3115 		if (count)
3116 			(void)sprintf(cp, "%d", count);
3117 		if ((fd = open(count ? new : local,
3118 		    O_RDWR | O_CREAT | O_EXCL, 0666)) >= 0) {
3119 			*name = count ? new : local;
3120 			return (fd);
3121 		}
3122 		if (errno != EEXIST) {
3123 			perror_reply(553, count ? new : local);
3124 			return (-1);
3125 		}
3126 	}
3127 	reply(452, "Unique file name cannot be created.");
3128 	return (-1);
3129 }
3130 
3131 /*
3132  * Format and send reply containing system error number.
3133  */
3134 void
3135 perror_reply(int code, char *string)
3136 {
3137 
3138 	reply(code, "%s: %s.", string, strerror(errno));
3139 }
3140 
3141 static char *onefile[] = {
3142 	"",
3143 	0
3144 };
3145 
3146 void
3147 send_file_list(char *whichf)
3148 {
3149 	struct stat st;
3150 	DIR *dirp = NULL;
3151 	struct dirent *dir;
3152 	FILE *dout = NULL;
3153 	char **dirlist, *dirname;
3154 	int simple = 0;
3155 	int freeglob = 0;
3156 	glob_t gl;
3157 
3158 	if (strpbrk(whichf, "~{[*?") != NULL) {
3159 		int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE;
3160 
3161 		memset(&gl, 0, sizeof(gl));
3162 		gl.gl_matchc = MAXGLOBARGS;
3163 		flags |= GLOB_LIMIT;
3164 		freeglob = 1;
3165 		if (glob(whichf, flags, 0, &gl)) {
3166 			reply(550, "No matching files found.");
3167 			goto out;
3168 		} else if (gl.gl_pathc == 0) {
3169 			errno = ENOENT;
3170 			perror_reply(550, whichf);
3171 			goto out;
3172 		}
3173 		dirlist = gl.gl_pathv;
3174 	} else {
3175 		onefile[0] = whichf;
3176 		dirlist = onefile;
3177 		simple = 1;
3178 	}
3179 
3180 	while ((dirname = *dirlist++)) {
3181 		if (stat(dirname, &st) < 0) {
3182 			/*
3183 			 * If user typed "ls -l", etc, and the client
3184 			 * used NLST, do what the user meant.
3185 			 */
3186 			if (dirname[0] == '-' && *dirlist == NULL &&
3187 			    dout == NULL)
3188 				retrieve(_PATH_LS " %s", dirname);
3189 			else
3190 				perror_reply(550, whichf);
3191 			goto out;
3192 		}
3193 
3194 		if (S_ISREG(st.st_mode)) {
3195 			if (dout == NULL) {
3196 				dout = dataconn("file list", -1, "w");
3197 				if (dout == NULL)
3198 					goto out;
3199 				STARTXFER;
3200 			}
3201 			START_UNSAFE;
3202 			fprintf(dout, "%s%s\n", dirname,
3203 				type == TYPE_A ? "\r" : "");
3204 			END_UNSAFE;
3205 			if (ferror(dout))
3206 				goto data_err;
3207 			byte_count += strlen(dirname) +
3208 				      (type == TYPE_A ? 2 : 1);
3209 			CHECKOOB(goto abrt);
3210 			continue;
3211 		} else if (!S_ISDIR(st.st_mode))
3212 			continue;
3213 
3214 		if ((dirp = opendir(dirname)) == NULL)
3215 			continue;
3216 
3217 		while ((dir = readdir(dirp)) != NULL) {
3218 			char nbuf[MAXPATHLEN];
3219 
3220 			CHECKOOB(goto abrt);
3221 
3222 			if (dir->d_name[0] == '.' && dir->d_namlen == 1)
3223 				continue;
3224 			if (dir->d_name[0] == '.' && dir->d_name[1] == '.' &&
3225 			    dir->d_namlen == 2)
3226 				continue;
3227 
3228 			snprintf(nbuf, sizeof(nbuf),
3229 				"%s/%s", dirname, dir->d_name);
3230 
3231 			/*
3232 			 * We have to do a stat to insure it's
3233 			 * not a directory or special file.
3234 			 */
3235 			if (simple || (stat(nbuf, &st) == 0 &&
3236 			    S_ISREG(st.st_mode))) {
3237 				if (dout == NULL) {
3238 					dout = dataconn("file list", -1, "w");
3239 					if (dout == NULL)
3240 						goto out;
3241 					STARTXFER;
3242 				}
3243 				START_UNSAFE;
3244 				if (nbuf[0] == '.' && nbuf[1] == '/')
3245 					fprintf(dout, "%s%s\n", &nbuf[2],
3246 						type == TYPE_A ? "\r" : "");
3247 				else
3248 					fprintf(dout, "%s%s\n", nbuf,
3249 						type == TYPE_A ? "\r" : "");
3250 				END_UNSAFE;
3251 				if (ferror(dout))
3252 					goto data_err;
3253 				byte_count += strlen(nbuf) +
3254 					      (type == TYPE_A ? 2 : 1);
3255 				CHECKOOB(goto abrt);
3256 			}
3257 		}
3258 		(void) closedir(dirp);
3259 		dirp = NULL;
3260 	}
3261 
3262 	if (dout == NULL)
3263 		reply(550, "No files found.");
3264 	else if (ferror(dout))
3265 data_err:	perror_reply(550, "Data connection");
3266 	else
3267 		reply(226, "Transfer complete.");
3268 out:
3269 	if (dout) {
3270 		ENDXFER;
3271 abrt:
3272 		(void) fclose(dout);
3273 		data = -1;
3274 		pdata = -1;
3275 	}
3276 	if (dirp)
3277 		(void) closedir(dirp);
3278 	if (freeglob) {
3279 		freeglob = 0;
3280 		globfree(&gl);
3281 	}
3282 }
3283 
3284 void
3285 reapchild(int signo)
3286 {
3287 	while (waitpid(-1, NULL, WNOHANG) > 0);
3288 }
3289 
3290 static void
3291 appendf(char **strp, char *fmt, ...)
3292 {
3293 	va_list ap;
3294 	char *ostr, *p;
3295 
3296 	va_start(ap, fmt);
3297 	vasprintf(&p, fmt, ap);
3298 	va_end(ap);
3299 	if (p == NULL)
3300 		fatalerror("Ran out of memory.");
3301 	if (*strp == NULL)
3302 		*strp = p;
3303 	else {
3304 		ostr = *strp;
3305 		asprintf(strp, "%s%s", ostr, p);
3306 		if (*strp == NULL)
3307 			fatalerror("Ran out of memory.");
3308 		free(ostr);
3309 	}
3310 }
3311 
3312 static void
3313 logcmd(char *cmd, char *file1, char *file2, off_t cnt)
3314 {
3315 	char *msg = NULL;
3316 	char wd[MAXPATHLEN + 1];
3317 
3318 	if (logging <= 1)
3319 		return;
3320 
3321 	if (getcwd(wd, sizeof(wd) - 1) == NULL)
3322 		strcpy(wd, strerror(errno));
3323 
3324 	appendf(&msg, "%s", cmd);
3325 	if (file1)
3326 		appendf(&msg, " %s", file1);
3327 	if (file2)
3328 		appendf(&msg, " %s", file2);
3329 	if (cnt >= 0)
3330 		appendf(&msg, " = %jd bytes", (intmax_t)cnt);
3331 	appendf(&msg, " (wd: %s", wd);
3332 	if (guest || dochroot)
3333 		appendf(&msg, "; chrooted");
3334 	appendf(&msg, ")");
3335 	syslog(LOG_INFO, "%s", msg);
3336 	free(msg);
3337 }
3338 
3339 static void
3340 logxfer(char *name, off_t size, time_t start)
3341 {
3342 	char buf[MAXPATHLEN + 1024];
3343 	char path[MAXPATHLEN + 1];
3344 	time_t now;
3345 
3346 	if (statfd >= 0) {
3347 		time(&now);
3348 		if (realpath(name, path) == NULL) {
3349 			syslog(LOG_NOTICE, "realpath failed on %s: %m", path);
3350 			return;
3351 		}
3352 		snprintf(buf, sizeof(buf), "%.20s!%s!%s!%s!%jd!%ld\n",
3353 			ctime(&now)+4, ident, remotehost,
3354 			path, (intmax_t)size,
3355 			(long)(now - start + (now == start)));
3356 		write(statfd, buf, strlen(buf));
3357 	}
3358 }
3359 
3360 static char *
3361 doublequote(char *s)
3362 {
3363 	int n;
3364 	char *p, *s2;
3365 
3366 	for (p = s, n = 0; *p; p++)
3367 		if (*p == '"')
3368 			n++;
3369 
3370 	if ((s2 = malloc(p - s + n + 1)) == NULL)
3371 		return (NULL);
3372 
3373 	for (p = s2; *s; s++, p++) {
3374 		if ((*p = *s) == '"')
3375 			*(++p) = '"';
3376 	}
3377 	*p = '\0';
3378 
3379 	return (s2);
3380 }
3381 
3382 /* setup server socket for specified address family */
3383 /* if af is PF_UNSPEC more than one socket may be returned */
3384 /* the returned list is dynamically allocated, so caller needs to free it */
3385 static int *
3386 socksetup(int af, char *bindname, const char *bindport)
3387 {
3388 	struct addrinfo hints, *res, *r;
3389 	int error, maxs, *s, *socks;
3390 	const int on = 1;
3391 
3392 	memset(&hints, 0, sizeof(hints));
3393 	hints.ai_flags = AI_PASSIVE;
3394 	hints.ai_family = af;
3395 	hints.ai_socktype = SOCK_STREAM;
3396 	error = getaddrinfo(bindname, bindport, &hints, &res);
3397 	if (error) {
3398 		syslog(LOG_ERR, "%s", gai_strerror(error));
3399 		if (error == EAI_SYSTEM)
3400 			syslog(LOG_ERR, "%s", strerror(errno));
3401 		return NULL;
3402 	}
3403 
3404 	/* Count max number of sockets we may open */
3405 	for (maxs = 0, r = res; r; r = r->ai_next, maxs++)
3406 		;
3407 	socks = malloc((maxs + 1) * sizeof(int));
3408 	if (!socks) {
3409 		freeaddrinfo(res);
3410 		syslog(LOG_ERR, "couldn't allocate memory for sockets");
3411 		return NULL;
3412 	}
3413 
3414 	*socks = 0;   /* num of sockets counter at start of array */
3415 	s = socks + 1;
3416 	for (r = res; r; r = r->ai_next) {
3417 		*s = socket(r->ai_family, r->ai_socktype, r->ai_protocol);
3418 		if (*s < 0) {
3419 			syslog(LOG_DEBUG, "control socket: %m");
3420 			continue;
3421 		}
3422 		if (setsockopt(*s, SOL_SOCKET, SO_REUSEADDR,
3423 		    &on, sizeof(on)) < 0)
3424 			syslog(LOG_WARNING,
3425 			    "control setsockopt (SO_REUSEADDR): %m");
3426 		if (r->ai_family == AF_INET6) {
3427 			if (setsockopt(*s, IPPROTO_IPV6, IPV6_V6ONLY,
3428 			    &on, sizeof(on)) < 0)
3429 				syslog(LOG_WARNING,
3430 				    "control setsockopt (IPV6_V6ONLY): %m");
3431 		}
3432 		if (bind(*s, r->ai_addr, r->ai_addrlen) < 0) {
3433 			syslog(LOG_DEBUG, "control bind: %m");
3434 			close(*s);
3435 			continue;
3436 		}
3437 		(*socks)++;
3438 		s++;
3439 	}
3440 
3441 	if (res)
3442 		freeaddrinfo(res);
3443 
3444 	if (*socks == 0) {
3445 		syslog(LOG_ERR, "control socket: Couldn't bind to any socket");
3446 		free(socks);
3447 		return NULL;
3448 	}
3449 	return(socks);
3450 }
3451