xref: /freebsd/libexec/ftpd/ftpd.c (revision 43581d7b6617959e4452094d9330ef020034a6c9)
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 #endif /* not lint */
42 
43 #include <sys/cdefs.h>
44 /*
45  * FTP server.
46  */
47 #include <sys/param.h>
48 #include <sys/ioctl.h>
49 #include <sys/mman.h>
50 #include <sys/socket.h>
51 #include <sys/stat.h>
52 #include <sys/time.h>
53 #include <sys/wait.h>
54 
55 #include <netinet/in.h>
56 #include <netinet/in_systm.h>
57 #include <netinet/ip.h>
58 #include <netinet/tcp.h>
59 
60 #define	FTP_NAMES
61 #include <arpa/ftp.h>
62 #include <arpa/inet.h>
63 #include <arpa/telnet.h>
64 
65 #include <ctype.h>
66 #include <dirent.h>
67 #include <err.h>
68 #include <errno.h>
69 #include <fcntl.h>
70 #include <glob.h>
71 #include <limits.h>
72 #include <netdb.h>
73 #include <pwd.h>
74 #include <grp.h>
75 #include <signal.h>
76 #include <stdint.h>
77 #include <stdio.h>
78 #include <stdlib.h>
79 #include <string.h>
80 #include <syslog.h>
81 #include <time.h>
82 #include <unistd.h>
83 #include <libutil.h>
84 #ifdef	LOGIN_CAP
85 #include <login_cap.h>
86 #endif
87 
88 #ifdef USE_PAM
89 #include <security/pam_appl.h>
90 #endif
91 
92 #include "blacklist_client.h"
93 #include "pathnames.h"
94 #include "extern.h"
95 
96 #include <stdarg.h>
97 
98 static char version[] = "Version 6.00LS";
99 #undef main
100 
101 union sockunion ctrl_addr;
102 union sockunion data_source;
103 union sockunion data_dest;
104 union sockunion his_addr;
105 union sockunion pasv_addr;
106 
107 int	daemon_mode;
108 int	data;
109 int	dataport;
110 int	hostinfo = 1;	/* print host-specific info in messages */
111 int	logged_in;
112 struct	passwd *pw;
113 char	*homedir;
114 int	ftpdebug;
115 int	timeout = 900;    /* timeout after 15 minutes of inactivity */
116 int	maxtimeout = 7200;/* don't allow idle time to be set beyond 2 hours */
117 int	logging;
118 int	restricted_data_ports = 1;
119 int	paranoid = 1;	  /* be extra careful about security */
120 int	anon_only = 0;    /* Only anonymous ftp allowed */
121 int	assumeutf8 = 0;   /* Assume that server file names are in UTF-8 */
122 int	guest;
123 int	dochroot;
124 char	*chrootdir;
125 int	dowtmp = 1;
126 int	stats;
127 int	statfd = -1;
128 int	type;
129 int	form;
130 int	stru;			/* avoid C keyword */
131 int	mode;
132 int	usedefault = 1;		/* for data transfers */
133 int	pdata = -1;		/* for passive mode */
134 int	readonly = 0;		/* Server is in readonly mode.	*/
135 int	noepsv = 0;		/* EPSV command is disabled.	*/
136 int	noretr = 0;		/* RETR command is disabled.	*/
137 int	noguestretr = 0;	/* RETR command is disabled for anon users. */
138 int	noguestmkd = 0;		/* MKD command is disabled for anon users. */
139 int	noguestmod = 1;		/* anon users may not modify existing files. */
140 int	use_blacklist = 0;
141 
142 off_t	file_size;
143 off_t	byte_count;
144 #if !defined(CMASK) || CMASK == 0
145 #undef CMASK
146 #define CMASK 027
147 #endif
148 int	defumask = CMASK;		/* default umask value */
149 char	tmpline[7];
150 char	*hostname;
151 int	epsvall = 0;
152 
153 #ifdef VIRTUAL_HOSTING
154 char	*ftpuser;
155 
156 static struct ftphost {
157 	struct ftphost	*next;
158 	struct addrinfo *hostinfo;
159 	char		*hostname;
160 	char		*anonuser;
161 	char		*statfile;
162 	char		*welcome;
163 	char		*loginmsg;
164 } *thishost, *firsthost;
165 
166 #endif
167 char	remotehost[NI_MAXHOST];
168 char	*ident = NULL;
169 
170 static char	wtmpid[20];
171 
172 #ifdef USE_PAM
173 static int	auth_pam(struct passwd**, const char*);
174 pam_handle_t	*pamh = NULL;
175 #endif
176 
177 char	*pid_file = NULL; /* means default location to pidfile(3) */
178 
179 /*
180  * Limit number of pathnames that glob can return.
181  * A limit of 0 indicates the number of pathnames is unlimited.
182  */
183 #define MAXGLOBARGS	16384
184 #
185 
186 /*
187  * Timeout intervals for retrying connections
188  * to hosts that don't accept PORT cmds.  This
189  * is a kludge, but given the problems with TCP...
190  */
191 #define	SWAITMAX	90	/* wait at most 90 seconds */
192 #define	SWAITINT	5	/* interval between retries */
193 
194 int	swaitmax = SWAITMAX;
195 int	swaitint = SWAITINT;
196 
197 #ifdef SETPROCTITLE
198 char	proctitle[LINE_MAX];	/* initial part of title */
199 #endif /* SETPROCTITLE */
200 
201 #define LOGCMD(cmd, file)		logcmd((cmd), (file), NULL, -1)
202 #define LOGCMD2(cmd, file1, file2)	logcmd((cmd), (file1), (file2), -1)
203 #define LOGBYTES(cmd, file, cnt)	logcmd((cmd), (file), NULL, (cnt))
204 
205 static	volatile sig_atomic_t recvurg;
206 static	int transflag;		/* NB: for debugging only */
207 
208 #define STARTXFER	flagxfer(1)
209 #define ENDXFER		flagxfer(0)
210 
211 #define START_UNSAFE	maskurg(1)
212 #define END_UNSAFE	maskurg(0)
213 
214 /* It's OK to put an `else' clause after this macro. */
215 #define CHECKOOB(action)						\
216 	if (recvurg) {							\
217 		recvurg = 0;						\
218 		if (myoob()) {						\
219 			ENDXFER;					\
220 			action;						\
221 		}							\
222 	}
223 
224 #ifdef VIRTUAL_HOSTING
225 static void	 inithosts(int);
226 static void	 selecthost(union sockunion *);
227 #endif
228 static void	 ack(char *);
229 static void	 sigurg(int);
230 static void	 maskurg(int);
231 static void	 flagxfer(int);
232 static int	 myoob(void);
233 static int	 checkuser(char *, char *, int, char **, int *);
234 static FILE	*dataconn(char *, off_t, char *);
235 static void	 dolog(struct sockaddr *);
236 static void	 end_login(void);
237 static FILE	*getdatasock(char *);
238 static int	 guniquefd(char *, char **);
239 static void	 lostconn(int);
240 static void	 sigquit(int);
241 static int	 receive_data(FILE *, FILE *);
242 static int	 send_data(FILE *, FILE *, size_t, off_t, int);
243 static struct passwd *
244 		 sgetpwnam(char *);
245 static char	*sgetsave(char *);
246 static void	 reapchild(int);
247 static void	 appendf(char **, char *, ...) __printflike(2, 3);
248 static void	 logcmd(char *, char *, char *, off_t);
249 static void      logxfer(char *, off_t, time_t);
250 static char	*doublequote(char *);
251 static int	*socksetup(int, char *, const char *);
252 
253 int
254 main(int argc, char *argv[], char **envp)
255 {
256 	socklen_t addrlen;
257 	int ch, on = 1, tos, s = STDIN_FILENO;
258 	char *cp, line[LINE_MAX];
259 	FILE *fd;
260 	char	*bindname = NULL;
261 	const char *bindport = "ftp";
262 	int	family = AF_UNSPEC;
263 	struct sigaction sa;
264 
265 	tzset();		/* in case no timezone database in ~ftp */
266 	sigemptyset(&sa.sa_mask);
267 	sa.sa_flags = SA_RESTART;
268 
269 	/*
270 	 * Prevent diagnostic messages from appearing on stderr.
271 	 * We run as a daemon or from inetd; in both cases, there's
272 	 * more reason in logging to syslog.
273 	 */
274 	(void) freopen(_PATH_DEVNULL, "w", stderr);
275 	opterr = 0;
276 
277 	/*
278 	 * LOG_NDELAY sets up the logging connection immediately,
279 	 * necessary for anonymous ftp's that chroot and can't do it later.
280 	 */
281 	openlog("ftpd", LOG_PID | LOG_NDELAY, LOG_FTP);
282 
283 	while ((ch = getopt(argc, argv,
284 	                    "468a:ABdDEhlmMoOp:P:rRSt:T:u:UvW")) != -1) {
285 		switch (ch) {
286 		case '4':
287 			family = (family == AF_INET6) ? AF_UNSPEC : AF_INET;
288 			break;
289 
290 		case '6':
291 			family = (family == AF_INET) ? AF_UNSPEC : AF_INET6;
292 			break;
293 
294 		case '8':
295 			assumeutf8 = 1;
296 			break;
297 
298 		case 'a':
299 			bindname = optarg;
300 			break;
301 
302 		case 'A':
303 			anon_only = 1;
304 			break;
305 
306 		case 'B':
307 #ifdef USE_BLACKLIST
308 			use_blacklist = 1;
309 #else
310 			syslog(LOG_WARNING, "not compiled with USE_BLACKLIST support");
311 #endif
312 			break;
313 
314 		case 'd':
315 			ftpdebug++;
316 			break;
317 
318 		case 'D':
319 			daemon_mode++;
320 			break;
321 
322 		case 'E':
323 			noepsv = 1;
324 			break;
325 
326 		case 'h':
327 			hostinfo = 0;
328 			break;
329 
330 		case 'l':
331 			logging++;	/* > 1 == extra logging */
332 			break;
333 
334 		case 'm':
335 			noguestmod = 0;
336 			break;
337 
338 		case 'M':
339 			noguestmkd = 1;
340 			break;
341 
342 		case 'o':
343 			noretr = 1;
344 			break;
345 
346 		case 'O':
347 			noguestretr = 1;
348 			break;
349 
350 		case 'p':
351 			pid_file = optarg;
352 			break;
353 
354 		case 'P':
355 			bindport = optarg;
356 			break;
357 
358 		case 'r':
359 			readonly = 1;
360 			break;
361 
362 		case 'R':
363 			paranoid = 0;
364 			break;
365 
366 		case 'S':
367 			stats++;
368 			break;
369 
370 		case 't':
371 			timeout = atoi(optarg);
372 			if (maxtimeout < timeout)
373 				maxtimeout = timeout;
374 			break;
375 
376 		case 'T':
377 			maxtimeout = atoi(optarg);
378 			if (timeout > maxtimeout)
379 				timeout = maxtimeout;
380 			break;
381 
382 		case 'u':
383 		    {
384 			long val = 0;
385 
386 			val = strtol(optarg, &optarg, 8);
387 			if (*optarg != '\0' || val < 0)
388 				syslog(LOG_WARNING, "bad value for -u");
389 			else
390 				defumask = val;
391 			break;
392 		    }
393 		case 'U':
394 			restricted_data_ports = 0;
395 			break;
396 
397 		case 'v':
398 			ftpdebug++;
399 			break;
400 
401 		case 'W':
402 			dowtmp = 0;
403 			break;
404 
405 		default:
406 			syslog(LOG_WARNING, "unknown flag -%c ignored", optopt);
407 			break;
408 		}
409 	}
410 
411 	/* handle filesize limit gracefully */
412 	sa.sa_handler = SIG_IGN;
413 	(void)sigaction(SIGXFSZ, &sa, NULL);
414 
415 	if (daemon_mode) {
416 		int *ctl_sock, fd, maxfd = -1, nfds, i;
417 		fd_set defreadfds, readfds;
418 		pid_t pid;
419 		struct pidfh *pfh;
420 
421 		if ((pfh = pidfile_open(pid_file, 0600, &pid)) == NULL) {
422 			if (errno == EEXIST) {
423 				syslog(LOG_ERR, "%s already running, pid %d",
424 				       getprogname(), (int)pid);
425 				exit(1);
426 			}
427 			syslog(LOG_WARNING, "pidfile_open: %m");
428 		}
429 
430 		/*
431 		 * Detach from parent.
432 		 */
433 		if (daemon(1, 1) < 0) {
434 			syslog(LOG_ERR, "failed to become a daemon");
435 			exit(1);
436 		}
437 
438 		if (pfh != NULL && pidfile_write(pfh) == -1)
439 			syslog(LOG_WARNING, "pidfile_write: %m");
440 
441 		sa.sa_handler = reapchild;
442 		(void)sigaction(SIGCHLD, &sa, NULL);
443 
444 #ifdef VIRTUAL_HOSTING
445 		inithosts(family);
446 #endif
447 
448 		/*
449 		 * Open a socket, bind it to the FTP port, and start
450 		 * listening.
451 		 */
452 		ctl_sock = socksetup(family, bindname, bindport);
453 		if (ctl_sock == NULL)
454 			exit(1);
455 
456 		FD_ZERO(&defreadfds);
457 		for (i = 1; i <= *ctl_sock; i++) {
458 			FD_SET(ctl_sock[i], &defreadfds);
459 			if (listen(ctl_sock[i], 32) < 0) {
460 				syslog(LOG_ERR, "control listen: %m");
461 				exit(1);
462 			}
463 			if (maxfd < ctl_sock[i])
464 				maxfd = ctl_sock[i];
465 		}
466 
467 		/*
468 		 * Loop forever accepting connection requests and forking off
469 		 * children to handle them.
470 		 */
471 		while (1) {
472 			FD_COPY(&defreadfds, &readfds);
473 			nfds = select(maxfd + 1, &readfds, NULL, NULL, 0);
474 			if (nfds <= 0) {
475 				if (nfds < 0 && errno != EINTR)
476 					syslog(LOG_WARNING, "select: %m");
477 				continue;
478 			}
479 
480 			pid = -1;
481                         for (i = 1; i <= *ctl_sock; i++)
482 				if (FD_ISSET(ctl_sock[i], &readfds)) {
483 					addrlen = sizeof(his_addr);
484 					fd = accept(ctl_sock[i],
485 					    (struct sockaddr *)&his_addr,
486 					    &addrlen);
487 					if (fd == -1) {
488 						syslog(LOG_WARNING,
489 						       "accept: %m");
490 						continue;
491 					}
492 					switch (pid = fork()) {
493 					case 0:
494 						/* child */
495 						(void) dup2(fd, s);
496 						(void) dup2(fd, STDOUT_FILENO);
497 						(void) close(fd);
498 						for (i = 1; i <= *ctl_sock; i++)
499 							close(ctl_sock[i]);
500 						if (pfh != NULL)
501 							pidfile_close(pfh);
502 						goto gotchild;
503 					case -1:
504 						syslog(LOG_WARNING, "fork: %m");
505 						/* FALLTHROUGH */
506 					default:
507 						close(fd);
508 					}
509 				}
510 		}
511 	} else {
512 		addrlen = sizeof(his_addr);
513 		if (getpeername(s, (struct sockaddr *)&his_addr, &addrlen) < 0) {
514 			syslog(LOG_ERR, "getpeername (%s): %m",argv[0]);
515 			exit(1);
516 		}
517 
518 #ifdef VIRTUAL_HOSTING
519 		if (his_addr.su_family == AF_INET6 &&
520 		    IN6_IS_ADDR_V4MAPPED(&his_addr.su_sin6.sin6_addr))
521 			family = AF_INET;
522 		else
523 			family = his_addr.su_family;
524 		inithosts(family);
525 #endif
526 	}
527 
528 gotchild:
529 	sa.sa_handler = SIG_DFL;
530 	(void)sigaction(SIGCHLD, &sa, NULL);
531 
532 	sa.sa_handler = sigurg;
533 	sa.sa_flags = 0;		/* don't restart syscalls for SIGURG */
534 	(void)sigaction(SIGURG, &sa, NULL);
535 
536 	sigfillset(&sa.sa_mask);	/* block all signals in handler */
537 	sa.sa_flags = SA_RESTART;
538 	sa.sa_handler = sigquit;
539 	(void)sigaction(SIGHUP, &sa, NULL);
540 	(void)sigaction(SIGINT, &sa, NULL);
541 	(void)sigaction(SIGQUIT, &sa, NULL);
542 	(void)sigaction(SIGTERM, &sa, NULL);
543 
544 	sa.sa_handler = lostconn;
545 	(void)sigaction(SIGPIPE, &sa, NULL);
546 
547 	addrlen = sizeof(ctrl_addr);
548 	if (getsockname(s, (struct sockaddr *)&ctrl_addr, &addrlen) < 0) {
549 		syslog(LOG_ERR, "getsockname (%s): %m",argv[0]);
550 		exit(1);
551 	}
552 	dataport = ntohs(ctrl_addr.su_port) - 1; /* as per RFC 959 */
553 #ifdef VIRTUAL_HOSTING
554 	/* select our identity from virtual host table */
555 	selecthost(&ctrl_addr);
556 #endif
557 #ifdef IP_TOS
558 	if (ctrl_addr.su_family == AF_INET)
559       {
560 	tos = IPTOS_LOWDELAY;
561 	if (setsockopt(s, IPPROTO_IP, IP_TOS, &tos, sizeof(int)) < 0)
562 		syslog(LOG_WARNING, "control setsockopt (IP_TOS): %m");
563       }
564 #endif
565 	/*
566 	 * Disable Nagle on the control channel so that we don't have to wait
567 	 * for peer's ACK before issuing our next reply.
568 	 */
569 	if (setsockopt(s, IPPROTO_TCP, TCP_NODELAY, &on, sizeof(on)) < 0)
570 		syslog(LOG_WARNING, "control setsockopt (TCP_NODELAY): %m");
571 
572 	data_source.su_port = htons(ntohs(ctrl_addr.su_port) - 1);
573 
574 	(void)snprintf(wtmpid, sizeof(wtmpid), "%xftpd", getpid());
575 
576 	/* Try to handle urgent data inline */
577 #ifdef SO_OOBINLINE
578 	if (setsockopt(s, SOL_SOCKET, SO_OOBINLINE, &on, sizeof(on)) < 0)
579 		syslog(LOG_WARNING, "control setsockopt (SO_OOBINLINE): %m");
580 #endif
581 
582 #ifdef	F_SETOWN
583 	if (fcntl(s, F_SETOWN, getpid()) == -1)
584 		syslog(LOG_ERR, "fcntl F_SETOWN: %m");
585 #endif
586 	dolog((struct sockaddr *)&his_addr);
587 	/*
588 	 * Set up default state
589 	 */
590 	data = -1;
591 	type = TYPE_A;
592 	form = FORM_N;
593 	stru = STRU_F;
594 	mode = MODE_S;
595 	tmpline[0] = '\0';
596 
597 	/* If logins are disabled, print out the message. */
598 	if ((fd = fopen(_PATH_NOLOGIN,"r")) != NULL) {
599 		while (fgets(line, sizeof(line), fd) != NULL) {
600 			if ((cp = strchr(line, '\n')) != NULL)
601 				*cp = '\0';
602 			lreply(530, "%s", line);
603 		}
604 		(void) fflush(stdout);
605 		(void) fclose(fd);
606 		reply(530, "System not available.");
607 		exit(0);
608 	}
609 #ifdef VIRTUAL_HOSTING
610 	fd = fopen(thishost->welcome, "r");
611 #else
612 	fd = fopen(_PATH_FTPWELCOME, "r");
613 #endif
614 	if (fd != NULL) {
615 		while (fgets(line, sizeof(line), fd) != NULL) {
616 			if ((cp = strchr(line, '\n')) != NULL)
617 				*cp = '\0';
618 			lreply(220, "%s", line);
619 		}
620 		(void) fflush(stdout);
621 		(void) fclose(fd);
622 		/* reply(220,) must follow */
623 	}
624 #ifndef VIRTUAL_HOSTING
625 	if ((hostname = malloc(MAXHOSTNAMELEN)) == NULL)
626 		fatalerror("Ran out of memory.");
627 	if (gethostname(hostname, MAXHOSTNAMELEN - 1) < 0)
628 		hostname[0] = '\0';
629 	hostname[MAXHOSTNAMELEN - 1] = '\0';
630 #endif
631 	if (hostinfo)
632 		reply(220, "%s FTP server (%s) ready.", hostname, version);
633 	else
634 		reply(220, "FTP server ready.");
635 	BLACKLIST_INIT();
636 	for (;;)
637 		(void) yyparse();
638 	/* NOTREACHED */
639 }
640 
641 static void
642 lostconn(int signo)
643 {
644 
645 	if (ftpdebug)
646 		syslog(LOG_DEBUG, "lost connection");
647 	dologout(1);
648 }
649 
650 static void
651 sigquit(int signo)
652 {
653 
654 	syslog(LOG_ERR, "got signal %d", signo);
655 	dologout(1);
656 }
657 
658 #ifdef VIRTUAL_HOSTING
659 /*
660  * read in virtual host tables (if they exist)
661  */
662 
663 static void
664 inithosts(int family)
665 {
666 	int insert;
667 	size_t len;
668 	FILE *fp;
669 	char *cp, *mp, *line;
670 	char *hostname;
671 	char *vhost, *anonuser, *statfile, *welcome, *loginmsg;
672 	struct ftphost *hrp, *lhrp;
673 	struct addrinfo hints, *res, *ai;
674 
675 	/*
676 	 * Fill in the default host information
677 	 */
678 	if ((hostname = malloc(MAXHOSTNAMELEN)) == NULL)
679 		fatalerror("Ran out of memory.");
680 	if (gethostname(hostname, MAXHOSTNAMELEN - 1) < 0)
681 		hostname[0] = '\0';
682 	hostname[MAXHOSTNAMELEN - 1] = '\0';
683 	if ((hrp = malloc(sizeof(struct ftphost))) == NULL)
684 		fatalerror("Ran out of memory.");
685 	hrp->hostname = hostname;
686 	hrp->hostinfo = NULL;
687 
688 	memset(&hints, 0, sizeof(hints));
689 	hints.ai_flags = AI_PASSIVE;
690 	hints.ai_family = family;
691 	hints.ai_socktype = SOCK_STREAM;
692 	if (getaddrinfo(hrp->hostname, NULL, &hints, &res) == 0)
693 		hrp->hostinfo = res;
694 	hrp->statfile = _PATH_FTPDSTATFILE;
695 	hrp->welcome  = _PATH_FTPWELCOME;
696 	hrp->loginmsg = _PATH_FTPLOGINMESG;
697 	hrp->anonuser = "ftp";
698 	hrp->next = NULL;
699 	thishost = firsthost = lhrp = hrp;
700 	if ((fp = fopen(_PATH_FTPHOSTS, "r")) != NULL) {
701 		int addrsize, gothost;
702 		void *addr;
703 		struct hostent *hp;
704 
705 		while ((line = fgetln(fp, &len)) != NULL) {
706 			int	i, hp_error;
707 
708 			/* skip comments */
709 			if (line[0] == '#')
710 				continue;
711 			if (line[len - 1] == '\n') {
712 				line[len - 1] = '\0';
713 				mp = NULL;
714 			} else {
715 				if ((mp = malloc(len + 1)) == NULL)
716 					fatalerror("Ran out of memory.");
717 				memcpy(mp, line, len);
718 				mp[len] = '\0';
719 				line = mp;
720 			}
721 			cp = strtok(line, " \t");
722 			/* skip empty lines */
723 			if (cp == NULL)
724 				goto nextline;
725 			vhost = cp;
726 
727 			/* set defaults */
728 			anonuser = "ftp";
729 			statfile = _PATH_FTPDSTATFILE;
730 			welcome  = _PATH_FTPWELCOME;
731 			loginmsg = _PATH_FTPLOGINMESG;
732 
733 			/*
734 			 * Preparse the line so we can use its info
735 			 * for all the addresses associated with
736 			 * the virtual host name.
737 			 * Field 0, the virtual host name, is special:
738 			 * it's already parsed off and will be strdup'ed
739 			 * later, after we know its canonical form.
740 			 */
741 			for (i = 1; i < 5 && (cp = strtok(NULL, " \t")); i++)
742 				if (*cp != '-' && (cp = strdup(cp)))
743 					switch (i) {
744 					case 1:	/* anon user permissions */
745 						anonuser = cp;
746 						break;
747 					case 2: /* statistics file */
748 						statfile = cp;
749 						break;
750 					case 3: /* welcome message */
751 						welcome  = cp;
752 						break;
753 					case 4: /* login message */
754 						loginmsg = cp;
755 						break;
756 					default: /* programming error */
757 						abort();
758 						/* NOTREACHED */
759 					}
760 
761 			hints.ai_flags = AI_PASSIVE;
762 			hints.ai_family = family;
763 			hints.ai_socktype = SOCK_STREAM;
764 			if (getaddrinfo(vhost, NULL, &hints, &res) != 0)
765 				goto nextline;
766 			for (ai = res; ai != NULL && ai->ai_addr != NULL;
767 			     ai = ai->ai_next) {
768 
769 			gothost = 0;
770 			for (hrp = firsthost; hrp != NULL; hrp = hrp->next) {
771 				struct addrinfo *hi;
772 
773 				for (hi = hrp->hostinfo; hi != NULL;
774 				     hi = hi->ai_next)
775 					if (hi->ai_addrlen == ai->ai_addrlen &&
776 					    memcmp(hi->ai_addr,
777 						   ai->ai_addr,
778 						   ai->ai_addr->sa_len) == 0) {
779 						gothost++;
780 						break;
781 					}
782 				if (gothost)
783 					break;
784 			}
785 			if (hrp == NULL) {
786 				if ((hrp = malloc(sizeof(struct ftphost))) == NULL)
787 					goto nextline;
788 				hrp->hostname = NULL;
789 				insert = 1;
790 			} else {
791 				if (hrp->hostinfo && hrp->hostinfo != res)
792 					freeaddrinfo(hrp->hostinfo);
793 				insert = 0; /* host already in the chain */
794 			}
795 			hrp->hostinfo = res;
796 
797 			/*
798 			 * determine hostname to use.
799 			 * force defined name if there is a valid alias
800 			 * otherwise fallback to primary hostname
801 			 */
802 			/* XXX: getaddrinfo() can't do alias check */
803 			switch(hrp->hostinfo->ai_family) {
804 			case AF_INET:
805 				addr = &((struct sockaddr_in *)hrp->hostinfo->ai_addr)->sin_addr;
806 				addrsize = sizeof(struct in_addr);
807 				break;
808 			case AF_INET6:
809 				addr = &((struct sockaddr_in6 *)hrp->hostinfo->ai_addr)->sin6_addr;
810 				addrsize = sizeof(struct in6_addr);
811 				break;
812 			default:
813 				/* should not reach here */
814 				freeaddrinfo(hrp->hostinfo);
815 				if (insert)
816 					free(hrp); /*not in chain, can free*/
817 				else
818 					hrp->hostinfo = NULL; /*mark as blank*/
819 				goto nextline;
820 				/* NOTREACHED */
821 			}
822 			if ((hp = getipnodebyaddr(addr, addrsize,
823 						  hrp->hostinfo->ai_family,
824 						  &hp_error)) != NULL) {
825 				if (strcmp(vhost, hp->h_name) != 0) {
826 					if (hp->h_aliases == NULL)
827 						vhost = hp->h_name;
828 					else {
829 						i = 0;
830 						while (hp->h_aliases[i] &&
831 						       strcmp(vhost, hp->h_aliases[i]) != 0)
832 							++i;
833 						if (hp->h_aliases[i] == NULL)
834 							vhost = hp->h_name;
835 					}
836 				}
837 			}
838 			if (hrp->hostname &&
839 			    strcmp(hrp->hostname, vhost) != 0) {
840 				free(hrp->hostname);
841 				hrp->hostname = NULL;
842 			}
843 			if (hrp->hostname == NULL &&
844 			    (hrp->hostname = strdup(vhost)) == NULL) {
845 				freeaddrinfo(hrp->hostinfo);
846 				hrp->hostinfo = NULL; /* mark as blank */
847 				if (hp)
848 					freehostent(hp);
849 				goto nextline;
850 			}
851 			hrp->anonuser = anonuser;
852 			hrp->statfile = statfile;
853 			hrp->welcome  = welcome;
854 			hrp->loginmsg = loginmsg;
855 			if (insert) {
856 				hrp->next  = NULL;
857 				lhrp->next = hrp;
858 				lhrp = hrp;
859 			}
860 			if (hp)
861 				freehostent(hp);
862 		      }
863 nextline:
864 			if (mp)
865 				free(mp);
866 		}
867 		(void) fclose(fp);
868 	}
869 }
870 
871 static void
872 selecthost(union sockunion *su)
873 {
874 	struct ftphost	*hrp;
875 	u_int16_t port;
876 #ifdef INET6
877 	struct in6_addr *mapped_in6 = NULL;
878 #endif
879 	struct addrinfo *hi;
880 
881 #ifdef INET6
882 	/*
883 	 * XXX IPv4 mapped IPv6 addr consideraton,
884 	 * specified in rfc2373.
885 	 */
886 	if (su->su_family == AF_INET6 &&
887 	    IN6_IS_ADDR_V4MAPPED(&su->su_sin6.sin6_addr))
888 		mapped_in6 = &su->su_sin6.sin6_addr;
889 #endif
890 
891 	hrp = thishost = firsthost;	/* default */
892 	port = su->su_port;
893 	su->su_port = 0;
894 	while (hrp != NULL) {
895 	    for (hi = hrp->hostinfo; hi != NULL; hi = hi->ai_next) {
896 		if (memcmp(su, hi->ai_addr, hi->ai_addrlen) == 0) {
897 			thishost = hrp;
898 			goto found;
899 		}
900 #ifdef INET6
901 		/* XXX IPv4 mapped IPv6 addr consideraton */
902 		if (hi->ai_addr->sa_family == AF_INET && mapped_in6 != NULL &&
903 		    (memcmp(&mapped_in6->s6_addr[12],
904 			    &((struct sockaddr_in *)hi->ai_addr)->sin_addr,
905 			    sizeof(struct in_addr)) == 0)) {
906 			thishost = hrp;
907 			goto found;
908 		}
909 #endif
910 	    }
911 	    hrp = hrp->next;
912 	}
913 found:
914 	su->su_port = port;
915 	/* setup static variables as appropriate */
916 	hostname = thishost->hostname;
917 	ftpuser = thishost->anonuser;
918 }
919 #endif
920 
921 /*
922  * Helper function for sgetpwnam().
923  */
924 static char *
925 sgetsave(char *s)
926 {
927 	char *new = malloc(strlen(s) + 1);
928 
929 	if (new == NULL) {
930 		reply(421, "Ran out of memory.");
931 		dologout(1);
932 		/* NOTREACHED */
933 	}
934 	(void) strcpy(new, s);
935 	return (new);
936 }
937 
938 /*
939  * Save the result of a getpwnam.  Used for USER command, since
940  * the data returned must not be clobbered by any other command
941  * (e.g., globbing).
942  * NB: The data returned by sgetpwnam() will remain valid until
943  * the next call to this function.  Its difference from getpwnam()
944  * is that sgetpwnam() is known to be called from ftpd code only.
945  */
946 static struct passwd *
947 sgetpwnam(char *name)
948 {
949 	static struct passwd save;
950 	struct passwd *p;
951 
952 	if ((p = getpwnam(name)) == NULL)
953 		return (p);
954 	if (save.pw_name) {
955 		free(save.pw_name);
956 		free(save.pw_passwd);
957 		free(save.pw_class);
958 		free(save.pw_gecos);
959 		free(save.pw_dir);
960 		free(save.pw_shell);
961 	}
962 	save = *p;
963 	save.pw_name = sgetsave(p->pw_name);
964 	save.pw_passwd = sgetsave(p->pw_passwd);
965 	save.pw_class = sgetsave(p->pw_class);
966 	save.pw_gecos = sgetsave(p->pw_gecos);
967 	save.pw_dir = sgetsave(p->pw_dir);
968 	save.pw_shell = sgetsave(p->pw_shell);
969 	return (&save);
970 }
971 
972 static int login_attempts;	/* number of failed login attempts */
973 static int askpasswd;		/* had user command, ask for passwd */
974 static char curname[MAXLOGNAME];	/* current USER name */
975 
976 /*
977  * USER command.
978  * Sets global passwd pointer pw if named account exists and is acceptable;
979  * sets askpasswd if a PASS command is expected.  If logged in previously,
980  * need to reset state.  If name is "ftp" or "anonymous", the name is not in
981  * _PATH_FTPUSERS, and ftp account exists, set guest and pw, then just return.
982  * If account doesn't exist, ask for passwd anyway.  Otherwise, check user
983  * requesting login privileges.  Disallow anyone who does not have a standard
984  * shell as returned by getusershell().  Disallow anyone mentioned in the file
985  * _PATH_FTPUSERS to allow people such as root and uucp to be avoided.
986  */
987 void
988 user(char *name)
989 {
990 	int ecode;
991 	char *cp, *shell;
992 
993 	if (logged_in) {
994 		if (guest) {
995 			reply(530, "Can't change user from guest login.");
996 			return;
997 		} else if (dochroot) {
998 			reply(530, "Can't change user from chroot user.");
999 			return;
1000 		}
1001 		end_login();
1002 	}
1003 
1004 	guest = 0;
1005 #ifdef VIRTUAL_HOSTING
1006 	pw = sgetpwnam(thishost->anonuser);
1007 #else
1008 	pw = sgetpwnam("ftp");
1009 #endif
1010 	if (strcmp(name, "ftp") == 0 || strcmp(name, "anonymous") == 0) {
1011 		if (checkuser(_PATH_FTPUSERS, "ftp", 0, NULL, &ecode) ||
1012 		    (ecode != 0 && ecode != ENOENT))
1013 			reply(530, "User %s access denied.", name);
1014 		else if (checkuser(_PATH_FTPUSERS, "anonymous", 0, NULL, &ecode) ||
1015 		    (ecode != 0 && ecode != ENOENT))
1016 			reply(530, "User %s access denied.", name);
1017 		else if (pw != NULL) {
1018 			guest = 1;
1019 			askpasswd = 1;
1020 			reply(331,
1021 			"Guest login ok, send your email address as password.");
1022 		} else
1023 			reply(530, "User %s unknown.", name);
1024 		if (!askpasswd && logging)
1025 			syslog(LOG_NOTICE,
1026 			    "ANONYMOUS FTP LOGIN REFUSED FROM %s", remotehost);
1027 		return;
1028 	}
1029 	if (anon_only != 0) {
1030 		reply(530, "Sorry, only anonymous ftp allowed.");
1031 		return;
1032 	}
1033 
1034 	if ((pw = sgetpwnam(name))) {
1035 		if ((shell = pw->pw_shell) == NULL || *shell == 0)
1036 			shell = _PATH_BSHELL;
1037 		setusershell();
1038 		while ((cp = getusershell()) != NULL)
1039 			if (strcmp(cp, shell) == 0)
1040 				break;
1041 		endusershell();
1042 
1043 		if (cp == NULL ||
1044 		    (checkuser(_PATH_FTPUSERS, name, 1, NULL, &ecode) ||
1045 		    (ecode != 0 && ecode != ENOENT))) {
1046 			reply(530, "User %s access denied.", name);
1047 			if (logging)
1048 				syslog(LOG_NOTICE,
1049 				    "FTP LOGIN REFUSED FROM %s, %s",
1050 				    remotehost, name);
1051 			pw = NULL;
1052 			return;
1053 		}
1054 	}
1055 	if (logging)
1056 		strlcpy(curname, name, sizeof(curname));
1057 
1058 	reply(331, "Password required for %s.", name);
1059 	askpasswd = 1;
1060 	/*
1061 	 * Delay before reading passwd after first failed
1062 	 * attempt to slow down passwd-guessing programs.
1063 	 */
1064 	if (login_attempts)
1065 		sleep(login_attempts);
1066 }
1067 
1068 /*
1069  * Check if a user is in the file "fname",
1070  * return a pointer to a malloc'd string with the rest
1071  * of the matching line in "residue" if not NULL.
1072  */
1073 static int
1074 checkuser(char *fname, char *name, int pwset, char **residue, int *ecode)
1075 {
1076 	FILE *fd;
1077 	int found = 0;
1078 	size_t len;
1079 	char *line, *mp, *p;
1080 
1081 	if (ecode != NULL)
1082 		*ecode = 0;
1083 	if ((fd = fopen(fname, "r")) != NULL) {
1084 		while (!found && (line = fgetln(fd, &len)) != NULL) {
1085 			/* skip comments */
1086 			if (line[0] == '#')
1087 				continue;
1088 			if (line[len - 1] == '\n') {
1089 				line[len - 1] = '\0';
1090 				mp = NULL;
1091 			} else {
1092 				if ((mp = malloc(len + 1)) == NULL)
1093 					fatalerror("Ran out of memory.");
1094 				memcpy(mp, line, len);
1095 				mp[len] = '\0';
1096 				line = mp;
1097 			}
1098 			/* avoid possible leading and trailing whitespace */
1099 			p = strtok(line, " \t");
1100 			/* skip empty lines */
1101 			if (p == NULL)
1102 				goto nextline;
1103 			/*
1104 			 * if first chr is '@', check group membership
1105 			 */
1106 			if (p[0] == '@') {
1107 				int i = 0;
1108 				struct group *grp;
1109 
1110 				if (p[1] == '\0') /* single @ matches anyone */
1111 					found = 1;
1112 				else {
1113 					if ((grp = getgrnam(p+1)) == NULL)
1114 						goto nextline;
1115 					/*
1116 					 * Check user's default group
1117 					 */
1118 					if (pwset && grp->gr_gid == pw->pw_gid)
1119 						found = 1;
1120 					/*
1121 					 * Check supplementary groups
1122 					 */
1123 					while (!found && grp->gr_mem[i])
1124 						found = strcmp(name,
1125 							grp->gr_mem[i++])
1126 							== 0;
1127 				}
1128 			}
1129 			/*
1130 			 * Otherwise, just check for username match
1131 			 */
1132 			else
1133 				found = strcmp(p, name) == 0;
1134 			/*
1135 			 * Save the rest of line to "residue" if matched
1136 			 */
1137 			if (found && residue) {
1138 				if ((p = strtok(NULL, "")) != NULL)
1139 					p += strspn(p, " \t");
1140 				if (p && *p) {
1141 				 	if ((*residue = strdup(p)) == NULL)
1142 						fatalerror("Ran out of memory.");
1143 				} else
1144 					*residue = NULL;
1145 			}
1146 nextline:
1147 			if (mp)
1148 				free(mp);
1149 		}
1150 		(void) fclose(fd);
1151 	} else if (ecode != NULL)
1152 		*ecode = errno;
1153 	return (found);
1154 }
1155 
1156 /*
1157  * Terminate login as previous user, if any, resetting state;
1158  * used when USER command is given or login fails.
1159  */
1160 static void
1161 end_login(void)
1162 {
1163 #ifdef USE_PAM
1164 	int e;
1165 #endif
1166 
1167 	(void) seteuid(0);
1168 #ifdef	LOGIN_CAP
1169 	setusercontext(NULL, getpwuid(0), 0, LOGIN_SETALL & ~(LOGIN_SETLOGIN |
1170 		       LOGIN_SETUSER | LOGIN_SETGROUP | LOGIN_SETPATH |
1171 		       LOGIN_SETENV));
1172 #endif
1173 	if (logged_in && dowtmp)
1174 		ftpd_logwtmp(wtmpid, NULL, NULL);
1175 	pw = NULL;
1176 #ifdef USE_PAM
1177 	if (pamh) {
1178 		if ((e = pam_setcred(pamh, PAM_DELETE_CRED)) != PAM_SUCCESS)
1179 			syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, e));
1180 		if ((e = pam_close_session(pamh,0)) != PAM_SUCCESS)
1181 			syslog(LOG_ERR, "pam_close_session: %s", pam_strerror(pamh, e));
1182 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS)
1183 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1184 		pamh = NULL;
1185 	}
1186 #endif
1187 	logged_in = 0;
1188 	guest = 0;
1189 	dochroot = 0;
1190 }
1191 
1192 #ifdef USE_PAM
1193 
1194 /*
1195  * the following code is stolen from imap-uw PAM authentication module and
1196  * login.c
1197  */
1198 #define COPY_STRING(s) (s ? strdup(s) : NULL)
1199 
1200 struct cred_t {
1201 	const char *uname;		/* user name */
1202 	const char *pass;		/* password */
1203 };
1204 typedef struct cred_t cred_t;
1205 
1206 static int
1207 auth_conv(int num_msg, const struct pam_message **msg,
1208 	  struct pam_response **resp, void *appdata)
1209 {
1210 	int i;
1211 	cred_t *cred = (cred_t *) appdata;
1212 	struct pam_response *reply;
1213 
1214 	reply = calloc(num_msg, sizeof *reply);
1215 	if (reply == NULL)
1216 		return PAM_BUF_ERR;
1217 
1218 	for (i = 0; i < num_msg; i++) {
1219 		switch (msg[i]->msg_style) {
1220 		case PAM_PROMPT_ECHO_ON:	/* assume want user name */
1221 			reply[i].resp_retcode = PAM_SUCCESS;
1222 			reply[i].resp = COPY_STRING(cred->uname);
1223 			/* PAM frees resp. */
1224 			break;
1225 		case PAM_PROMPT_ECHO_OFF:	/* assume want password */
1226 			reply[i].resp_retcode = PAM_SUCCESS;
1227 			reply[i].resp = COPY_STRING(cred->pass);
1228 			/* PAM frees resp. */
1229 			break;
1230 		case PAM_TEXT_INFO:
1231 		case PAM_ERROR_MSG:
1232 			reply[i].resp_retcode = PAM_SUCCESS;
1233 			reply[i].resp = NULL;
1234 			break;
1235 		default:			/* unknown message style */
1236 			free(reply);
1237 			return PAM_CONV_ERR;
1238 		}
1239 	}
1240 
1241 	*resp = reply;
1242 	return PAM_SUCCESS;
1243 }
1244 
1245 /*
1246  * Attempt to authenticate the user using PAM.  Returns 0 if the user is
1247  * authenticated, or 1 if not authenticated.  If some sort of PAM system
1248  * error occurs (e.g., the "/etc/pam.conf" file is missing) then this
1249  * function returns -1.  This can be used as an indication that we should
1250  * fall back to a different authentication mechanism.
1251  */
1252 static int
1253 auth_pam(struct passwd **ppw, const char *pass)
1254 {
1255 	const char *tmpl_user;
1256 	const void *item;
1257 	int rval;
1258 	int e;
1259 	cred_t auth_cred = { (*ppw)->pw_name, pass };
1260 	struct pam_conv conv = { &auth_conv, &auth_cred };
1261 
1262 	e = pam_start("ftpd", (*ppw)->pw_name, &conv, &pamh);
1263 	if (e != PAM_SUCCESS) {
1264 		/*
1265 		 * In OpenPAM, it's OK to pass NULL to pam_strerror()
1266 		 * if context creation has failed in the first place.
1267 		 */
1268 		syslog(LOG_ERR, "pam_start: %s", pam_strerror(NULL, e));
1269 		return -1;
1270 	}
1271 
1272 	e = pam_set_item(pamh, PAM_RHOST, remotehost);
1273 	if (e != PAM_SUCCESS) {
1274 		syslog(LOG_ERR, "pam_set_item(PAM_RHOST): %s",
1275 			pam_strerror(pamh, e));
1276 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
1277 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1278 		}
1279 		pamh = NULL;
1280 		return -1;
1281 	}
1282 
1283 	e = pam_authenticate(pamh, 0);
1284 	switch (e) {
1285 	case PAM_SUCCESS:
1286 		/*
1287 		 * With PAM we support the concept of a "template"
1288 		 * user.  The user enters a login name which is
1289 		 * authenticated by PAM, usually via a remote service
1290 		 * such as RADIUS or TACACS+.  If authentication
1291 		 * succeeds, a different but related "template" name
1292 		 * is used for setting the credentials, shell, and
1293 		 * home directory.  The name the user enters need only
1294 		 * exist on the remote authentication server, but the
1295 		 * template name must be present in the local password
1296 		 * database.
1297 		 *
1298 		 * This is supported by two various mechanisms in the
1299 		 * individual modules.  However, from the application's
1300 		 * point of view, the template user is always passed
1301 		 * back as a changed value of the PAM_USER item.
1302 		 */
1303 		if ((e = pam_get_item(pamh, PAM_USER, &item)) ==
1304 		    PAM_SUCCESS) {
1305 			tmpl_user = (const char *) item;
1306 			if (strcmp((*ppw)->pw_name, tmpl_user) != 0)
1307 				*ppw = getpwnam(tmpl_user);
1308 		} else
1309 			syslog(LOG_ERR, "Couldn't get PAM_USER: %s",
1310 			    pam_strerror(pamh, e));
1311 		rval = 0;
1312 		break;
1313 
1314 	case PAM_AUTH_ERR:
1315 	case PAM_USER_UNKNOWN:
1316 	case PAM_MAXTRIES:
1317 		rval = 1;
1318 		break;
1319 
1320 	default:
1321 		syslog(LOG_ERR, "pam_authenticate: %s", pam_strerror(pamh, e));
1322 		rval = -1;
1323 		break;
1324 	}
1325 
1326 	if (rval == 0) {
1327 		e = pam_acct_mgmt(pamh, 0);
1328 		if (e != PAM_SUCCESS) {
1329 			syslog(LOG_ERR, "pam_acct_mgmt: %s",
1330 						pam_strerror(pamh, e));
1331 			rval = 1;
1332 		}
1333 	}
1334 
1335 	if (rval != 0) {
1336 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
1337 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1338 		}
1339 		pamh = NULL;
1340 	}
1341 	return rval;
1342 }
1343 
1344 #endif /* USE_PAM */
1345 
1346 void
1347 pass(char *passwd)
1348 {
1349 	int rval, ecode;
1350 	FILE *fd;
1351 #ifdef	LOGIN_CAP
1352 	login_cap_t *lc = NULL;
1353 #endif
1354 #ifdef USE_PAM
1355 	int e;
1356 #endif
1357 	char *residue = NULL;
1358 	char *xpasswd;
1359 
1360 	if (logged_in || askpasswd == 0) {
1361 		reply(503, "Login with USER first.");
1362 		return;
1363 	}
1364 	askpasswd = 0;
1365 	if (!guest) {		/* "ftp" is only account allowed no password */
1366 		if (pw == NULL) {
1367 			rval = 1;	/* failure below */
1368 			goto skip;
1369 		}
1370 #ifdef USE_PAM
1371 		rval = auth_pam(&pw, passwd);
1372 		if (rval >= 0) {
1373 			goto skip;
1374 		}
1375 #endif
1376 		xpasswd = crypt(passwd, pw->pw_passwd);
1377 		if (passwd[0] == '\0' && pw->pw_passwd[0] != '\0')
1378 			xpasswd = ":";
1379 		rval = strcmp(pw->pw_passwd, xpasswd);
1380 		if (pw->pw_expire && time(NULL) >= pw->pw_expire)
1381 			rval = 1;	/* failure */
1382 skip:
1383 		/*
1384 		 * If rval == 1, the user failed the authentication check
1385 		 * above.  If rval == 0, either PAM or local authentication
1386 		 * succeeded.
1387 		 */
1388 		if (rval) {
1389 			reply(530, "Login incorrect.");
1390 			BLACKLIST_NOTIFY(BLACKLIST_AUTH_FAIL, STDIN_FILENO, "Login incorrect");
1391 			if (logging) {
1392 				syslog(LOG_NOTICE,
1393 				    "FTP LOGIN FAILED FROM %s",
1394 				    remotehost);
1395 				syslog(LOG_AUTHPRIV | LOG_NOTICE,
1396 				    "FTP LOGIN FAILED FROM %s, %s",
1397 				    remotehost, curname);
1398 			}
1399 			pw = NULL;
1400 			if (login_attempts++ >= 5) {
1401 				syslog(LOG_NOTICE,
1402 				    "repeated login failures from %s",
1403 				    remotehost);
1404 				exit(0);
1405 			}
1406 			return;
1407 		} else {
1408 			BLACKLIST_NOTIFY(BLACKLIST_AUTH_OK, STDIN_FILENO, "Login successful");
1409 		}
1410 	}
1411 	login_attempts = 0;		/* this time successful */
1412 	if (setegid(pw->pw_gid) < 0) {
1413 		reply(550, "Can't set gid.");
1414 		return;
1415 	}
1416 	/* May be overridden by login.conf */
1417 	(void) umask(defumask);
1418 #ifdef	LOGIN_CAP
1419 	if ((lc = login_getpwclass(pw)) != NULL) {
1420 		char	remote_ip[NI_MAXHOST];
1421 
1422 		if (getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
1423 			remote_ip, sizeof(remote_ip) - 1, NULL, 0,
1424 			NI_NUMERICHOST))
1425 				*remote_ip = 0;
1426 		remote_ip[sizeof(remote_ip) - 1] = 0;
1427 		if (!auth_hostok(lc, remotehost, remote_ip)) {
1428 			syslog(LOG_INFO|LOG_AUTH,
1429 			    "FTP LOGIN FAILED (HOST) as %s: permission denied.",
1430 			    pw->pw_name);
1431 			reply(530, "Permission denied.");
1432 			pw = NULL;
1433 			return;
1434 		}
1435 		if (!auth_timeok(lc, time(NULL))) {
1436 			reply(530, "Login not available right now.");
1437 			pw = NULL;
1438 			return;
1439 		}
1440 	}
1441 	setusercontext(lc, pw, 0, LOGIN_SETALL &
1442 		       ~(LOGIN_SETRESOURCES | LOGIN_SETUSER | LOGIN_SETPATH | LOGIN_SETENV));
1443 #else
1444 	setlogin(pw->pw_name);
1445 	(void) initgroups(pw->pw_name, pw->pw_gid);
1446 #endif
1447 
1448 #ifdef USE_PAM
1449 	if (pamh) {
1450 		if ((e = pam_open_session(pamh, 0)) != PAM_SUCCESS) {
1451 			syslog(LOG_ERR, "pam_open_session: %s", pam_strerror(pamh, e));
1452 		} else if ((e = pam_setcred(pamh, PAM_ESTABLISH_CRED)) != PAM_SUCCESS) {
1453 			syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, e));
1454 		}
1455 	}
1456 #endif
1457 
1458 	dochroot =
1459 		checkuser(_PATH_FTPCHROOT, pw->pw_name, 1, &residue, &ecode)
1460 #ifdef	LOGIN_CAP	/* Allow login.conf configuration as well */
1461 		|| login_getcapbool(lc, "ftp-chroot", 0)
1462 #endif
1463 	;
1464 	/*
1465 	 * It is possible that checkuser() failed to open the chroot file.
1466 	 * If this is the case, report that logins are un-available, since we
1467 	 * have no way of checking whether or not the user should be chrooted.
1468 	 * We ignore ENOENT since it is not required that this file be present.
1469 	 */
1470 	if (ecode != 0 && ecode != ENOENT) {
1471 		reply(530, "Login not available right now.");
1472 		return;
1473 	}
1474 	chrootdir = NULL;
1475 
1476 	/* Disable wtmp logging when chrooting. */
1477 	if (dochroot || guest)
1478 		dowtmp = 0;
1479 	if (dowtmp)
1480 		ftpd_logwtmp(wtmpid, pw->pw_name,
1481 		    (struct sockaddr *)&his_addr);
1482 	logged_in = 1;
1483 
1484 #ifdef	LOGIN_CAP
1485 	setusercontext(lc, pw, 0, LOGIN_SETRESOURCES);
1486 #endif
1487 
1488 	if (guest && stats && statfd < 0) {
1489 #ifdef VIRTUAL_HOSTING
1490 		statfd = open(thishost->statfile, O_WRONLY|O_APPEND);
1491 #else
1492 		statfd = open(_PATH_FTPDSTATFILE, O_WRONLY|O_APPEND);
1493 #endif
1494 		if (statfd < 0)
1495 			stats = 0;
1496 	}
1497 
1498 	/*
1499 	 * For a chrooted local user,
1500 	 * a) see whether ftpchroot(5) specifies a chroot directory,
1501 	 * b) extract the directory pathname from the line,
1502 	 * c) expand it to the absolute pathname if necessary.
1503 	 */
1504 	if (dochroot && residue &&
1505 	    (chrootdir = strtok(residue, " \t")) != NULL) {
1506 		if (chrootdir[0] != '/')
1507 			asprintf(&chrootdir, "%s/%s", pw->pw_dir, chrootdir);
1508 		else
1509 			chrootdir = strdup(chrootdir); /* make it permanent */
1510 		if (chrootdir == NULL)
1511 			fatalerror("Ran out of memory.");
1512 	}
1513 	if (guest || dochroot) {
1514 		/*
1515 		 * If no chroot directory set yet, use the login directory.
1516 		 * Copy it so it can be modified while pw->pw_dir stays intact.
1517 		 */
1518 		if (chrootdir == NULL &&
1519 		    (chrootdir = strdup(pw->pw_dir)) == NULL)
1520 			fatalerror("Ran out of memory.");
1521 		/*
1522 		 * Check for the "/chroot/./home" syntax,
1523 		 * separate the chroot and home directory pathnames.
1524 		 */
1525 		if ((homedir = strstr(chrootdir, "/./")) != NULL) {
1526 			*(homedir++) = '\0';	/* wipe '/' */
1527 			homedir++;		/* skip '.' */
1528 		} else {
1529 			/*
1530 			 * We MUST do a chdir() after the chroot. Otherwise
1531 			 * the old current directory will be accessible as "."
1532 			 * outside the new root!
1533 			 */
1534 			homedir = "/";
1535 		}
1536 		/*
1537 		 * Finally, do chroot()
1538 		 */
1539 		if (chroot(chrootdir) < 0) {
1540 			reply(550, "Can't change root.");
1541 			goto bad;
1542 		}
1543 		__FreeBSD_libc_enter_restricted_mode();
1544 	} else	/* real user w/o chroot */
1545 		homedir = pw->pw_dir;
1546 	/*
1547 	 * Set euid *before* doing chdir() so
1548 	 * a) the user won't be carried to a directory that he couldn't reach
1549 	 *    on his own due to no permission to upper path components,
1550 	 * b) NFS mounted homedirs w/restrictive permissions will be accessible
1551 	 *    (uid 0 has no root power over NFS if not mapped explicitly.)
1552 	 */
1553 	if (seteuid(pw->pw_uid) < 0) {
1554 		if (guest || dochroot) {
1555 			fatalerror("Can't set uid.");
1556 		} else {
1557 			reply(550, "Can't set uid.");
1558 			goto bad;
1559 		}
1560 	}
1561 	/*
1562 	 * Do not allow the session to live if we're chroot()'ed and chdir()
1563 	 * fails. Otherwise the chroot jail can be escaped.
1564 	 */
1565 	if (chdir(homedir) < 0) {
1566 		if (guest || dochroot) {
1567 			fatalerror("Can't change to base directory.");
1568 		} else {
1569 			if (chdir("/") < 0) {
1570 				reply(550, "Root is inaccessible.");
1571 				goto bad;
1572 			}
1573 			lreply(230, "No directory! Logging in with home=/.");
1574 		}
1575 	}
1576 
1577 	/*
1578 	 * Display a login message, if it exists.
1579 	 * N.B. reply(230,) must follow the message.
1580 	 */
1581 #ifdef VIRTUAL_HOSTING
1582 	fd = fopen(thishost->loginmsg, "r");
1583 #else
1584 	fd = fopen(_PATH_FTPLOGINMESG, "r");
1585 #endif
1586 	if (fd != NULL) {
1587 		char *cp, line[LINE_MAX];
1588 
1589 		while (fgets(line, sizeof(line), fd) != NULL) {
1590 			if ((cp = strchr(line, '\n')) != NULL)
1591 				*cp = '\0';
1592 			lreply(230, "%s", line);
1593 		}
1594 		(void) fflush(stdout);
1595 		(void) fclose(fd);
1596 	}
1597 	if (guest) {
1598 		if (ident != NULL)
1599 			free(ident);
1600 		ident = strdup(passwd);
1601 		if (ident == NULL)
1602 			fatalerror("Ran out of memory.");
1603 
1604 		reply(230, "Guest login ok, access restrictions apply.");
1605 #ifdef SETPROCTITLE
1606 #ifdef VIRTUAL_HOSTING
1607 		if (thishost != firsthost)
1608 			snprintf(proctitle, sizeof(proctitle),
1609 				 "%s: anonymous(%s)/%s", remotehost, hostname,
1610 				 passwd);
1611 		else
1612 #endif
1613 			snprintf(proctitle, sizeof(proctitle),
1614 				 "%s: anonymous/%s", remotehost, passwd);
1615 		setproctitle("%s", proctitle);
1616 #endif /* SETPROCTITLE */
1617 		if (logging)
1618 			syslog(LOG_INFO, "ANONYMOUS FTP LOGIN FROM %s, %s",
1619 			    remotehost, passwd);
1620 	} else {
1621 		if (dochroot)
1622 			reply(230, "User %s logged in, "
1623 				   "access restrictions apply.", pw->pw_name);
1624 		else
1625 			reply(230, "User %s logged in.", pw->pw_name);
1626 
1627 #ifdef SETPROCTITLE
1628 		snprintf(proctitle, sizeof(proctitle),
1629 			 "%s: user/%s", remotehost, pw->pw_name);
1630 		setproctitle("%s", proctitle);
1631 #endif /* SETPROCTITLE */
1632 		if (logging)
1633 			syslog(LOG_INFO, "FTP LOGIN FROM %s as %s",
1634 			    remotehost, pw->pw_name);
1635 	}
1636 	if (logging && (guest || dochroot))
1637 		syslog(LOG_INFO, "session root changed to %s", chrootdir);
1638 #ifdef	LOGIN_CAP
1639 	login_close(lc);
1640 #endif
1641 	if (residue)
1642 		free(residue);
1643 	return;
1644 bad:
1645 	/* Forget all about it... */
1646 #ifdef	LOGIN_CAP
1647 	login_close(lc);
1648 #endif
1649 	if (residue)
1650 		free(residue);
1651 	end_login();
1652 }
1653 
1654 void
1655 retrieve(char *cmd, char *name)
1656 {
1657 	FILE *fin, *dout;
1658 	struct stat st;
1659 	int (*closefunc)(FILE *);
1660 	time_t start;
1661 	char line[BUFSIZ];
1662 
1663 	if (cmd == 0) {
1664 		fin = fopen(name, "r"), closefunc = fclose;
1665 		st.st_size = 0;
1666 	} else {
1667 		(void) snprintf(line, sizeof(line), cmd, name);
1668 		name = line;
1669 		fin = ftpd_popen(line, "r"), closefunc = ftpd_pclose;
1670 		st.st_size = -1;
1671 		st.st_blksize = BUFSIZ;
1672 	}
1673 	if (fin == NULL) {
1674 		if (errno != 0) {
1675 			perror_reply(550, name);
1676 			if (cmd == 0) {
1677 				LOGCMD("get", name);
1678 			}
1679 		}
1680 		return;
1681 	}
1682 	byte_count = -1;
1683 	if (cmd == 0) {
1684 		if (fstat(fileno(fin), &st) < 0) {
1685 			perror_reply(550, name);
1686 			goto done;
1687 		}
1688 		if (!S_ISREG(st.st_mode)) {
1689 			/*
1690 			 * Never sending a raw directory is a workaround
1691 			 * for buggy clients that will attempt to RETR
1692 			 * a directory before listing it, e.g., Mozilla.
1693 			 * Preventing a guest from getting irregular files
1694 			 * is a simple security measure.
1695 			 */
1696 			if (S_ISDIR(st.st_mode) || guest) {
1697 				reply(550, "%s: not a plain file.", name);
1698 				goto done;
1699 			}
1700 			st.st_size = -1;
1701 			/* st.st_blksize is set for all descriptor types */
1702 		}
1703 	}
1704 	if (restart_point) {
1705 		if (type == TYPE_A) {
1706 			off_t i, n;
1707 			int c;
1708 
1709 			n = restart_point;
1710 			i = 0;
1711 			while (i++ < n) {
1712 				if ((c=getc(fin)) == EOF) {
1713 					perror_reply(550, name);
1714 					goto done;
1715 				}
1716 				if (c == '\n')
1717 					i++;
1718 			}
1719 		} else if (lseek(fileno(fin), restart_point, L_SET) < 0) {
1720 			perror_reply(550, name);
1721 			goto done;
1722 		}
1723 	}
1724 	dout = dataconn(name, st.st_size, "w");
1725 	if (dout == NULL)
1726 		goto done;
1727 	time(&start);
1728 	send_data(fin, dout, st.st_blksize, st.st_size,
1729 		  restart_point == 0 && cmd == 0 && S_ISREG(st.st_mode));
1730 	if (cmd == 0 && guest && stats && byte_count > 0)
1731 		logxfer(name, byte_count, start);
1732 	(void) fclose(dout);
1733 	data = -1;
1734 	pdata = -1;
1735 done:
1736 	if (cmd == 0)
1737 		LOGBYTES("get", name, byte_count);
1738 	(*closefunc)(fin);
1739 }
1740 
1741 void
1742 store(char *name, char *mode, int unique)
1743 {
1744 	int fd;
1745 	FILE *fout, *din;
1746 	int (*closefunc)(FILE *);
1747 
1748 	if (*mode == 'a') {		/* APPE */
1749 		if (unique) {
1750 			/* Programming error */
1751 			syslog(LOG_ERR, "Internal: unique flag to APPE");
1752 			unique = 0;
1753 		}
1754 		if (guest && noguestmod) {
1755 			reply(550, "Appending to existing file denied.");
1756 			goto err;
1757 		}
1758 		restart_point = 0;	/* not affected by preceding REST */
1759 	}
1760 	if (unique)			/* STOU overrides REST */
1761 		restart_point = 0;
1762 	if (guest && noguestmod) {
1763 		if (restart_point) {	/* guest STOR w/REST */
1764 			reply(550, "Modifying existing file denied.");
1765 			goto err;
1766 		} else			/* treat guest STOR as STOU */
1767 			unique = 1;
1768 	}
1769 
1770 	if (restart_point)
1771 		mode = "r+";	/* so ASCII manual seek can work */
1772 	if (unique) {
1773 		if ((fd = guniquefd(name, &name)) < 0)
1774 			goto err;
1775 		fout = fdopen(fd, mode);
1776 	} else
1777 		fout = fopen(name, mode);
1778 	closefunc = fclose;
1779 	if (fout == NULL) {
1780 		perror_reply(553, name);
1781 		goto err;
1782 	}
1783 	byte_count = -1;
1784 	if (restart_point) {
1785 		if (type == TYPE_A) {
1786 			off_t i, n;
1787 			int c;
1788 
1789 			n = restart_point;
1790 			i = 0;
1791 			while (i++ < n) {
1792 				if ((c=getc(fout)) == EOF) {
1793 					perror_reply(550, name);
1794 					goto done;
1795 				}
1796 				if (c == '\n')
1797 					i++;
1798 			}
1799 			/*
1800 			 * We must do this seek to "current" position
1801 			 * because we are changing from reading to
1802 			 * writing.
1803 			 */
1804 			if (fseeko(fout, 0, SEEK_CUR) < 0) {
1805 				perror_reply(550, name);
1806 				goto done;
1807 			}
1808 		} else if (lseek(fileno(fout), restart_point, L_SET) < 0) {
1809 			perror_reply(550, name);
1810 			goto done;
1811 		}
1812 	}
1813 	din = dataconn(name, -1, "r");
1814 	if (din == NULL)
1815 		goto done;
1816 	if (receive_data(din, fout) == 0) {
1817 		if (unique)
1818 			reply(226, "Transfer complete (unique file name:%s).",
1819 			    name);
1820 		else
1821 			reply(226, "Transfer complete.");
1822 	}
1823 	(void) fclose(din);
1824 	data = -1;
1825 	pdata = -1;
1826 done:
1827 	LOGBYTES(*mode == 'a' ? "append" : "put", name, byte_count);
1828 	(*closefunc)(fout);
1829 	return;
1830 err:
1831 	LOGCMD(*mode == 'a' ? "append" : "put" , name);
1832 	return;
1833 }
1834 
1835 static FILE *
1836 getdatasock(char *mode)
1837 {
1838 	int on = 1, s, t, tries;
1839 
1840 	if (data >= 0)
1841 		return (fdopen(data, mode));
1842 
1843 	s = socket(data_dest.su_family, SOCK_STREAM, 0);
1844 	if (s < 0)
1845 		goto bad;
1846 	if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
1847 		syslog(LOG_WARNING, "data setsockopt (SO_REUSEADDR): %m");
1848 	/* anchor socket to avoid multi-homing problems */
1849 	data_source = ctrl_addr;
1850 	data_source.su_port = htons(dataport);
1851 	(void) seteuid(0);
1852 	for (tries = 1; ; tries++) {
1853 		/*
1854 		 * We should loop here since it's possible that
1855 		 * another ftpd instance has passed this point and is
1856 		 * trying to open a data connection in active mode now.
1857 		 * Until the other connection is opened, we'll be getting
1858 		 * EADDRINUSE because no SOCK_STREAM sockets in the system
1859 		 * can share both local and remote addresses, localIP:20
1860 		 * and *:* in this case.
1861 		 */
1862 		if (bind(s, (struct sockaddr *)&data_source,
1863 		    data_source.su_len) >= 0)
1864 			break;
1865 		if (errno != EADDRINUSE || tries > 10)
1866 			goto bad;
1867 		sleep(tries);
1868 	}
1869 	(void) seteuid(pw->pw_uid);
1870 #ifdef IP_TOS
1871 	if (data_source.su_family == AF_INET)
1872       {
1873 	on = IPTOS_THROUGHPUT;
1874 	if (setsockopt(s, IPPROTO_IP, IP_TOS, &on, sizeof(int)) < 0)
1875 		syslog(LOG_WARNING, "data setsockopt (IP_TOS): %m");
1876       }
1877 #endif
1878 #ifdef TCP_NOPUSH
1879 	/*
1880 	 * Turn off push flag to keep sender TCP from sending short packets
1881 	 * at the boundaries of each write().
1882 	 */
1883 	on = 1;
1884 	if (setsockopt(s, IPPROTO_TCP, TCP_NOPUSH, &on, sizeof on) < 0)
1885 		syslog(LOG_WARNING, "data setsockopt (TCP_NOPUSH): %m");
1886 #endif
1887 	return (fdopen(s, mode));
1888 bad:
1889 	/* Return the real value of errno (close may change it) */
1890 	t = errno;
1891 	(void) seteuid(pw->pw_uid);
1892 	(void) close(s);
1893 	errno = t;
1894 	return (NULL);
1895 }
1896 
1897 static FILE *
1898 dataconn(char *name, off_t size, char *mode)
1899 {
1900 	char sizebuf[32];
1901 	FILE *file;
1902 	int retry = 0, tos, conerrno;
1903 
1904 	file_size = size;
1905 	byte_count = 0;
1906 	if (size != -1)
1907 		(void) snprintf(sizebuf, sizeof(sizebuf),
1908 				" (%jd bytes)", (intmax_t)size);
1909 	else
1910 		*sizebuf = '\0';
1911 	if (pdata >= 0) {
1912 		union sockunion from;
1913 		socklen_t fromlen = ctrl_addr.su_len;
1914 		int flags, s;
1915 		struct timeval timeout;
1916 		fd_set set;
1917 
1918 		FD_ZERO(&set);
1919 		FD_SET(pdata, &set);
1920 
1921 		timeout.tv_usec = 0;
1922 		timeout.tv_sec = 120;
1923 
1924 		/*
1925 		 * Granted a socket is in the blocking I/O mode,
1926 		 * accept() will block after a successful select()
1927 		 * if the selected connection dies in between.
1928 		 * Therefore set the non-blocking I/O flag here.
1929 		 */
1930 		if ((flags = fcntl(pdata, F_GETFL, 0)) == -1 ||
1931 		    fcntl(pdata, F_SETFL, flags | O_NONBLOCK) == -1)
1932 			goto pdata_err;
1933 		if (select(pdata+1, &set, NULL, NULL, &timeout) <= 0 ||
1934 		    (s = accept(pdata, (struct sockaddr *) &from, &fromlen)) < 0)
1935 			goto pdata_err;
1936 		(void) close(pdata);
1937 		pdata = s;
1938 		/*
1939 		 * Unset the inherited non-blocking I/O flag
1940 		 * on the child socket so stdio can work on it.
1941 		 */
1942 		if ((flags = fcntl(pdata, F_GETFL, 0)) == -1 ||
1943 		    fcntl(pdata, F_SETFL, flags & ~O_NONBLOCK) == -1)
1944 			goto pdata_err;
1945 #ifdef IP_TOS
1946 		if (from.su_family == AF_INET)
1947 	      {
1948 		tos = IPTOS_THROUGHPUT;
1949 		if (setsockopt(s, IPPROTO_IP, IP_TOS, &tos, sizeof(int)) < 0)
1950 			syslog(LOG_WARNING, "pdata setsockopt (IP_TOS): %m");
1951 	      }
1952 #endif
1953 		reply(150, "Opening %s mode data connection for '%s'%s.",
1954 		     type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
1955 		return (fdopen(pdata, mode));
1956 pdata_err:
1957 		reply(425, "Can't open data connection.");
1958 		(void) close(pdata);
1959 		pdata = -1;
1960 		return (NULL);
1961 	}
1962 	if (data >= 0) {
1963 		reply(125, "Using existing data connection for '%s'%s.",
1964 		    name, sizebuf);
1965 		usedefault = 1;
1966 		return (fdopen(data, mode));
1967 	}
1968 	if (usedefault)
1969 		data_dest = his_addr;
1970 	usedefault = 1;
1971 	do {
1972 		file = getdatasock(mode);
1973 		if (file == NULL) {
1974 			char hostbuf[NI_MAXHOST], portbuf[NI_MAXSERV];
1975 
1976 			if (getnameinfo((struct sockaddr *)&data_source,
1977 				data_source.su_len,
1978 				hostbuf, sizeof(hostbuf) - 1,
1979 				portbuf, sizeof(portbuf) - 1,
1980 				NI_NUMERICHOST|NI_NUMERICSERV))
1981 					*hostbuf = *portbuf = 0;
1982 			hostbuf[sizeof(hostbuf) - 1] = 0;
1983 			portbuf[sizeof(portbuf) - 1] = 0;
1984 			reply(425, "Can't create data socket (%s,%s): %s.",
1985 				hostbuf, portbuf, strerror(errno));
1986 			return (NULL);
1987 		}
1988 		data = fileno(file);
1989 		conerrno = 0;
1990 		if (connect(data, (struct sockaddr *)&data_dest,
1991 		    data_dest.su_len) == 0)
1992 			break;
1993 		conerrno = errno;
1994 		(void) fclose(file);
1995 		data = -1;
1996 		if (conerrno == EADDRINUSE) {
1997 			sleep(swaitint);
1998 			retry += swaitint;
1999 		} else {
2000 			break;
2001 		}
2002 	} while (retry <= swaitmax);
2003 	if (conerrno != 0) {
2004 		reply(425, "Can't build data connection: %s.",
2005 			   strerror(conerrno));
2006 		return (NULL);
2007 	}
2008 	reply(150, "Opening %s mode data connection for '%s'%s.",
2009 	     type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
2010 	return (file);
2011 }
2012 
2013 /*
2014  * A helper macro to avoid code duplication
2015  * in send_data() and receive_data().
2016  *
2017  * XXX We have to block SIGURG during putc() because BSD stdio
2018  * is unable to restart interrupted write operations and hence
2019  * the entire buffer contents will be lost as soon as a write()
2020  * call indicates EINTR to stdio.
2021  */
2022 #define FTPD_PUTC(ch, file, label)					\
2023 	do {								\
2024 		int ret;						\
2025 									\
2026 		do {							\
2027 			START_UNSAFE;					\
2028 			ret = putc((ch), (file));			\
2029 			END_UNSAFE;					\
2030 			CHECKOOB(return (-1))				\
2031 			else if (ferror(file))				\
2032 				goto label;				\
2033 			clearerr(file);					\
2034 		} while (ret == EOF);					\
2035 	} while (0)
2036 
2037 /*
2038  * Transfer the contents of "instr" to "outstr" peer using the appropriate
2039  * encapsulation of the data subject to Mode, Structure, and Type.
2040  *
2041  * NB: Form isn't handled.
2042  */
2043 static int
2044 send_data(FILE *instr, FILE *outstr, size_t blksize, off_t filesize, int isreg)
2045 {
2046 	int c, cp, filefd, netfd;
2047 	char *buf;
2048 
2049 	STARTXFER;
2050 
2051 	switch (type) {
2052 
2053 	case TYPE_A:
2054 		cp = EOF;
2055 		for (;;) {
2056 			c = getc(instr);
2057 			CHECKOOB(return (-1))
2058 			else if (c == EOF && ferror(instr))
2059 				goto file_err;
2060 			if (c == EOF) {
2061 				if (ferror(instr)) {	/* resume after OOB */
2062 					clearerr(instr);
2063 					continue;
2064 				}
2065 				if (feof(instr))	/* EOF */
2066 					break;
2067 				syslog(LOG_ERR, "Internal: impossible condition"
2068 						" on file after getc()");
2069 				goto file_err;
2070 			}
2071 			if (c == '\n' && cp != '\r') {
2072 				FTPD_PUTC('\r', outstr, data_err);
2073 				byte_count++;
2074 			}
2075 			FTPD_PUTC(c, outstr, data_err);
2076 			byte_count++;
2077 			cp = c;
2078 		}
2079 #ifdef notyet	/* BSD stdio isn't ready for that */
2080 		while (fflush(outstr) == EOF) {
2081 			CHECKOOB(return (-1))
2082 			else
2083 				goto data_err;
2084 			clearerr(outstr);
2085 		}
2086 		ENDXFER;
2087 #else
2088 		ENDXFER;
2089 		if (fflush(outstr) == EOF)
2090 			goto data_err;
2091 #endif
2092 		reply(226, "Transfer complete.");
2093 		return (0);
2094 
2095 	case TYPE_I:
2096 	case TYPE_L:
2097 		/*
2098 		 * isreg is only set if we are not doing restart and we
2099 		 * are sending a regular file
2100 		 */
2101 		netfd = fileno(outstr);
2102 		filefd = fileno(instr);
2103 
2104 		if (isreg) {
2105 			char *msg = "Transfer complete.";
2106 			off_t cnt, offset;
2107 			int err;
2108 
2109 			cnt = offset = 0;
2110 
2111 			while (filesize > 0) {
2112 				err = sendfile(filefd, netfd, offset, 0,
2113 					       NULL, &cnt, 0);
2114 				/*
2115 				 * Calculate byte_count before OOB processing.
2116 				 * It can be used in myoob() later.
2117 				 */
2118 				byte_count += cnt;
2119 				offset += cnt;
2120 				filesize -= cnt;
2121 				CHECKOOB(return (-1))
2122 				else if (err == -1) {
2123 					if (errno != EINTR &&
2124 					    cnt == 0 && offset == 0)
2125 						goto oldway;
2126 					goto data_err;
2127 				}
2128 				if (err == -1)	/* resume after OOB */
2129 					continue;
2130 				/*
2131 				 * We hit the EOF prematurely.
2132 				 * Perhaps the file was externally truncated.
2133 				 */
2134 				if (cnt == 0) {
2135 					msg = "Transfer finished due to "
2136 					      "premature end of file.";
2137 					break;
2138 				}
2139 			}
2140 			ENDXFER;
2141 			reply(226, "%s", msg);
2142 			return (0);
2143 		}
2144 
2145 oldway:
2146 		if ((buf = malloc(blksize)) == NULL) {
2147 			ENDXFER;
2148 			reply(451, "Ran out of memory.");
2149 			return (-1);
2150 		}
2151 
2152 		for (;;) {
2153 			int cnt, len;
2154 			char *bp;
2155 
2156 			cnt = read(filefd, buf, blksize);
2157 			CHECKOOB(free(buf); return (-1))
2158 			else if (cnt < 0) {
2159 				free(buf);
2160 				goto file_err;
2161 			}
2162 			if (cnt < 0)	/* resume after OOB */
2163 				continue;
2164 			if (cnt == 0)	/* EOF */
2165 				break;
2166 			for (len = cnt, bp = buf; len > 0;) {
2167 				cnt = write(netfd, bp, len);
2168 				CHECKOOB(free(buf); return (-1))
2169 				else if (cnt < 0) {
2170 					free(buf);
2171 					goto data_err;
2172 				}
2173 				if (cnt <= 0)
2174 					continue;
2175 				len -= cnt;
2176 				bp += cnt;
2177 				byte_count += cnt;
2178 			}
2179 		}
2180 		ENDXFER;
2181 		free(buf);
2182 		reply(226, "Transfer complete.");
2183 		return (0);
2184 	default:
2185 		ENDXFER;
2186 		reply(550, "Unimplemented TYPE %d in send_data.", type);
2187 		return (-1);
2188 	}
2189 
2190 data_err:
2191 	ENDXFER;
2192 	perror_reply(426, "Data connection");
2193 	return (-1);
2194 
2195 file_err:
2196 	ENDXFER;
2197 	perror_reply(551, "Error on input file");
2198 	return (-1);
2199 }
2200 
2201 /*
2202  * Transfer data from peer to "outstr" using the appropriate encapulation of
2203  * the data subject to Mode, Structure, and Type.
2204  *
2205  * N.B.: Form isn't handled.
2206  */
2207 static int
2208 receive_data(FILE *instr, FILE *outstr)
2209 {
2210 	int c, cp;
2211 	int bare_lfs = 0;
2212 
2213 	STARTXFER;
2214 
2215 	switch (type) {
2216 
2217 	case TYPE_I:
2218 	case TYPE_L:
2219 		for (;;) {
2220 			int cnt, len;
2221 			char *bp;
2222 			char buf[BUFSIZ];
2223 
2224 			cnt = read(fileno(instr), buf, sizeof(buf));
2225 			CHECKOOB(return (-1))
2226 			else if (cnt < 0)
2227 				goto data_err;
2228 			if (cnt < 0)	/* resume after OOB */
2229 				continue;
2230 			if (cnt == 0)	/* EOF */
2231 				break;
2232 			for (len = cnt, bp = buf; len > 0;) {
2233 				cnt = write(fileno(outstr), bp, len);
2234 				CHECKOOB(return (-1))
2235 				else if (cnt < 0)
2236 					goto file_err;
2237 				if (cnt <= 0)
2238 					continue;
2239 				len -= cnt;
2240 				bp += cnt;
2241 				byte_count += cnt;
2242 			}
2243 		}
2244 		ENDXFER;
2245 		return (0);
2246 
2247 	case TYPE_E:
2248 		ENDXFER;
2249 		reply(553, "TYPE E not implemented.");
2250 		return (-1);
2251 
2252 	case TYPE_A:
2253 		cp = EOF;
2254 		for (;;) {
2255 			c = getc(instr);
2256 			CHECKOOB(return (-1))
2257 			else if (c == EOF && ferror(instr))
2258 				goto data_err;
2259 			if (c == EOF && ferror(instr)) { /* resume after OOB */
2260 				clearerr(instr);
2261 				continue;
2262 			}
2263 
2264 			if (cp == '\r') {
2265 				if (c != '\n')
2266 					FTPD_PUTC('\r', outstr, file_err);
2267 			} else
2268 				if (c == '\n')
2269 					bare_lfs++;
2270 			if (c == '\r') {
2271 				byte_count++;
2272 				cp = c;
2273 				continue;
2274 			}
2275 
2276 			/* Check for EOF here in order not to lose last \r. */
2277 			if (c == EOF) {
2278 				if (feof(instr))	/* EOF */
2279 					break;
2280 				syslog(LOG_ERR, "Internal: impossible condition"
2281 						" on data stream after getc()");
2282 				goto data_err;
2283 			}
2284 
2285 			byte_count++;
2286 			FTPD_PUTC(c, outstr, file_err);
2287 			cp = c;
2288 		}
2289 #ifdef notyet	/* BSD stdio isn't ready for that */
2290 		while (fflush(outstr) == EOF) {
2291 			CHECKOOB(return (-1))
2292 			else
2293 				goto file_err;
2294 			clearerr(outstr);
2295 		}
2296 		ENDXFER;
2297 #else
2298 		ENDXFER;
2299 		if (fflush(outstr) == EOF)
2300 			goto file_err;
2301 #endif
2302 		if (bare_lfs) {
2303 			lreply(226,
2304 		"WARNING! %d bare linefeeds received in ASCII mode.",
2305 			    bare_lfs);
2306 		(void)printf("   File may not have transferred correctly.\r\n");
2307 		}
2308 		return (0);
2309 	default:
2310 		ENDXFER;
2311 		reply(550, "Unimplemented TYPE %d in receive_data.", type);
2312 		return (-1);
2313 	}
2314 
2315 data_err:
2316 	ENDXFER;
2317 	perror_reply(426, "Data connection");
2318 	return (-1);
2319 
2320 file_err:
2321 	ENDXFER;
2322 	perror_reply(452, "Error writing to file");
2323 	return (-1);
2324 }
2325 
2326 void
2327 statfilecmd(char *filename)
2328 {
2329 	FILE *fin;
2330 	int atstart;
2331 	int c, code;
2332 	char line[LINE_MAX];
2333 	struct stat st;
2334 
2335 	code = lstat(filename, &st) == 0 && S_ISDIR(st.st_mode) ? 212 : 213;
2336 	(void)snprintf(line, sizeof(line), _PATH_LS " -lgA %s", filename);
2337 	fin = ftpd_popen(line, "r");
2338 	if (fin == NULL) {
2339 		perror_reply(551, filename);
2340 		return;
2341 	}
2342 	lreply(code, "Status of %s:", filename);
2343 	atstart = 1;
2344 	while ((c = getc(fin)) != EOF) {
2345 		if (c == '\n') {
2346 			if (ferror(stdout)){
2347 				perror_reply(421, "Control connection");
2348 				(void) ftpd_pclose(fin);
2349 				dologout(1);
2350 				/* NOTREACHED */
2351 			}
2352 			if (ferror(fin)) {
2353 				perror_reply(551, filename);
2354 				(void) ftpd_pclose(fin);
2355 				return;
2356 			}
2357 			(void) putc('\r', stdout);
2358 		}
2359 		/*
2360 		 * RFC 959 says neutral text should be prepended before
2361 		 * a leading 3-digit number followed by whitespace, but
2362 		 * many ftp clients can be confused by any leading digits,
2363 		 * as a matter of fact.
2364 		 */
2365 		if (atstart && isdigit(c))
2366 			(void) putc(' ', stdout);
2367 		(void) putc(c, stdout);
2368 		atstart = (c == '\n');
2369 	}
2370 	(void) ftpd_pclose(fin);
2371 	reply(code, "End of status.");
2372 }
2373 
2374 void
2375 statcmd(void)
2376 {
2377 	union sockunion *su;
2378 	u_char *a, *p;
2379 	char hname[NI_MAXHOST];
2380 	int ispassive;
2381 
2382 	if (hostinfo) {
2383 		lreply(211, "%s FTP server status:", hostname);
2384 		printf("     %s\r\n", version);
2385 	} else
2386 		lreply(211, "FTP server status:");
2387 	printf("     Connected to %s", remotehost);
2388 	if (!getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
2389 			 hname, sizeof(hname) - 1, NULL, 0, NI_NUMERICHOST)) {
2390 		hname[sizeof(hname) - 1] = 0;
2391 		if (strcmp(hname, remotehost) != 0)
2392 			printf(" (%s)", hname);
2393 	}
2394 	printf("\r\n");
2395 	if (logged_in) {
2396 		if (guest)
2397 			printf("     Logged in anonymously\r\n");
2398 		else
2399 			printf("     Logged in as %s\r\n", pw->pw_name);
2400 	} else if (askpasswd)
2401 		printf("     Waiting for password\r\n");
2402 	else
2403 		printf("     Waiting for user name\r\n");
2404 	printf("     TYPE: %s", typenames[type]);
2405 	if (type == TYPE_A || type == TYPE_E)
2406 		printf(", FORM: %s", formnames[form]);
2407 	if (type == TYPE_L)
2408 #if CHAR_BIT == 8
2409 		printf(" %d", CHAR_BIT);
2410 #else
2411 		printf(" %d", bytesize);	/* need definition! */
2412 #endif
2413 	printf("; STRUcture: %s; transfer MODE: %s\r\n",
2414 	    strunames[stru], modenames[mode]);
2415 	if (data != -1)
2416 		printf("     Data connection open\r\n");
2417 	else if (pdata != -1) {
2418 		ispassive = 1;
2419 		su = &pasv_addr;
2420 		goto printaddr;
2421 	} else if (usedefault == 0) {
2422 		ispassive = 0;
2423 		su = &data_dest;
2424 printaddr:
2425 #define UC(b) (((int) b) & 0xff)
2426 		if (epsvall) {
2427 			printf("     EPSV only mode (EPSV ALL)\r\n");
2428 			goto epsvonly;
2429 		}
2430 
2431 		/* PORT/PASV */
2432 		if (su->su_family == AF_INET) {
2433 			a = (u_char *) &su->su_sin.sin_addr;
2434 			p = (u_char *) &su->su_sin.sin_port;
2435 			printf("     %s (%d,%d,%d,%d,%d,%d)\r\n",
2436 				ispassive ? "PASV" : "PORT",
2437 				UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
2438 				UC(p[0]), UC(p[1]));
2439 		}
2440 
2441 		/* LPRT/LPSV */
2442 	    {
2443 		int alen, af, i;
2444 
2445 		switch (su->su_family) {
2446 		case AF_INET:
2447 			a = (u_char *) &su->su_sin.sin_addr;
2448 			p = (u_char *) &su->su_sin.sin_port;
2449 			alen = sizeof(su->su_sin.sin_addr);
2450 			af = 4;
2451 			break;
2452 		case AF_INET6:
2453 			a = (u_char *) &su->su_sin6.sin6_addr;
2454 			p = (u_char *) &su->su_sin6.sin6_port;
2455 			alen = sizeof(su->su_sin6.sin6_addr);
2456 			af = 6;
2457 			break;
2458 		default:
2459 			af = 0;
2460 			break;
2461 		}
2462 		if (af) {
2463 			printf("     %s (%d,%d,", ispassive ? "LPSV" : "LPRT",
2464 				af, alen);
2465 			for (i = 0; i < alen; i++)
2466 				printf("%d,", UC(a[i]));
2467 			printf("%d,%d,%d)\r\n", 2, UC(p[0]), UC(p[1]));
2468 		}
2469 	    }
2470 
2471 epsvonly:;
2472 		/* EPRT/EPSV */
2473 	    {
2474 		int af;
2475 
2476 		switch (su->su_family) {
2477 		case AF_INET:
2478 			af = 1;
2479 			break;
2480 		case AF_INET6:
2481 			af = 2;
2482 			break;
2483 		default:
2484 			af = 0;
2485 			break;
2486 		}
2487 		if (af) {
2488 			union sockunion tmp;
2489 
2490 			tmp = *su;
2491 			if (tmp.su_family == AF_INET6)
2492 				tmp.su_sin6.sin6_scope_id = 0;
2493 			if (!getnameinfo((struct sockaddr *)&tmp, tmp.su_len,
2494 					hname, sizeof(hname) - 1, NULL, 0,
2495 					NI_NUMERICHOST)) {
2496 				hname[sizeof(hname) - 1] = 0;
2497 				printf("     %s |%d|%s|%d|\r\n",
2498 					ispassive ? "EPSV" : "EPRT",
2499 					af, hname, htons(tmp.su_port));
2500 			}
2501 		}
2502 	    }
2503 #undef UC
2504 	} else
2505 		printf("     No data connection\r\n");
2506 	reply(211, "End of status.");
2507 }
2508 
2509 void
2510 fatalerror(char *s)
2511 {
2512 
2513 	reply(451, "Error in server: %s", s);
2514 	reply(221, "Closing connection due to server error.");
2515 	dologout(0);
2516 	/* NOTREACHED */
2517 }
2518 
2519 void
2520 reply(int n, const char *fmt, ...)
2521 {
2522 	va_list ap;
2523 
2524 	(void)printf("%d ", n);
2525 	va_start(ap, fmt);
2526 	(void)vprintf(fmt, ap);
2527 	va_end(ap);
2528 	(void)printf("\r\n");
2529 	(void)fflush(stdout);
2530 	if (ftpdebug) {
2531 		syslog(LOG_DEBUG, "<--- %d ", n);
2532 		va_start(ap, fmt);
2533 		vsyslog(LOG_DEBUG, fmt, ap);
2534 		va_end(ap);
2535 	}
2536 }
2537 
2538 void
2539 lreply(int n, const char *fmt, ...)
2540 {
2541 	va_list ap;
2542 
2543 	(void)printf("%d- ", n);
2544 	va_start(ap, fmt);
2545 	(void)vprintf(fmt, ap);
2546 	va_end(ap);
2547 	(void)printf("\r\n");
2548 	(void)fflush(stdout);
2549 	if (ftpdebug) {
2550 		syslog(LOG_DEBUG, "<--- %d- ", n);
2551 		va_start(ap, fmt);
2552 		vsyslog(LOG_DEBUG, fmt, ap);
2553 		va_end(ap);
2554 	}
2555 }
2556 
2557 static void
2558 ack(char *s)
2559 {
2560 
2561 	reply(250, "%s command successful.", s);
2562 }
2563 
2564 void
2565 nack(char *s)
2566 {
2567 
2568 	reply(502, "%s command not implemented.", s);
2569 }
2570 
2571 /* ARGSUSED */
2572 void
2573 yyerror(char *s)
2574 {
2575 	char *cp;
2576 
2577 	if ((cp = strchr(cbuf,'\n')))
2578 		*cp = '\0';
2579 	reply(500, "%s: command not understood.", cbuf);
2580 }
2581 
2582 void
2583 delete(char *name)
2584 {
2585 	struct stat st;
2586 
2587 	LOGCMD("delete", name);
2588 	if (lstat(name, &st) < 0) {
2589 		perror_reply(550, name);
2590 		return;
2591 	}
2592 	if (S_ISDIR(st.st_mode)) {
2593 		if (rmdir(name) < 0) {
2594 			perror_reply(550, name);
2595 			return;
2596 		}
2597 		goto done;
2598 	}
2599 	if (guest && noguestmod) {
2600 		reply(550, "Operation not permitted.");
2601 		return;
2602 	}
2603 	if (unlink(name) < 0) {
2604 		perror_reply(550, name);
2605 		return;
2606 	}
2607 done:
2608 	ack("DELE");
2609 }
2610 
2611 void
2612 cwd(char *path)
2613 {
2614 
2615 	if (chdir(path) < 0)
2616 		perror_reply(550, path);
2617 	else
2618 		ack("CWD");
2619 }
2620 
2621 void
2622 makedir(char *name)
2623 {
2624 	char *s;
2625 
2626 	LOGCMD("mkdir", name);
2627 	if (guest && noguestmkd)
2628 		reply(550, "Operation not permitted.");
2629 	else if (mkdir(name, 0777) < 0)
2630 		perror_reply(550, name);
2631 	else {
2632 		if ((s = doublequote(name)) == NULL)
2633 			fatalerror("Ran out of memory.");
2634 		reply(257, "\"%s\" directory created.", s);
2635 		free(s);
2636 	}
2637 }
2638 
2639 void
2640 removedir(char *name)
2641 {
2642 
2643 	LOGCMD("rmdir", name);
2644 	if (rmdir(name) < 0)
2645 		perror_reply(550, name);
2646 	else
2647 		ack("RMD");
2648 }
2649 
2650 void
2651 pwd(void)
2652 {
2653 	char *s, path[MAXPATHLEN + 1];
2654 
2655 	if (getcwd(path, sizeof(path)) == NULL)
2656 		perror_reply(550, "Get current directory");
2657 	else {
2658 		if ((s = doublequote(path)) == NULL)
2659 			fatalerror("Ran out of memory.");
2660 		reply(257, "\"%s\" is current directory.", s);
2661 		free(s);
2662 	}
2663 }
2664 
2665 char *
2666 renamefrom(char *name)
2667 {
2668 	struct stat st;
2669 
2670 	if (guest && noguestmod) {
2671 		reply(550, "Operation not permitted.");
2672 		return (NULL);
2673 	}
2674 	if (lstat(name, &st) < 0) {
2675 		perror_reply(550, name);
2676 		return (NULL);
2677 	}
2678 	reply(350, "File exists, ready for destination name.");
2679 	return (name);
2680 }
2681 
2682 void
2683 renamecmd(char *from, char *to)
2684 {
2685 	struct stat st;
2686 
2687 	LOGCMD2("rename", from, to);
2688 
2689 	if (guest && (stat(to, &st) == 0)) {
2690 		reply(550, "%s: permission denied.", to);
2691 		return;
2692 	}
2693 
2694 	if (rename(from, to) < 0)
2695 		perror_reply(550, "rename");
2696 	else
2697 		ack("RNTO");
2698 }
2699 
2700 static void
2701 dolog(struct sockaddr *who)
2702 {
2703 	char who_name[NI_MAXHOST];
2704 
2705 	realhostname_sa(remotehost, sizeof(remotehost) - 1, who, who->sa_len);
2706 	remotehost[sizeof(remotehost) - 1] = 0;
2707 	if (getnameinfo(who, who->sa_len,
2708 		who_name, sizeof(who_name) - 1, NULL, 0, NI_NUMERICHOST))
2709 			*who_name = 0;
2710 	who_name[sizeof(who_name) - 1] = 0;
2711 
2712 #ifdef SETPROCTITLE
2713 #ifdef VIRTUAL_HOSTING
2714 	if (thishost != firsthost)
2715 		snprintf(proctitle, sizeof(proctitle), "%s: connected (to %s)",
2716 			 remotehost, hostname);
2717 	else
2718 #endif
2719 		snprintf(proctitle, sizeof(proctitle), "%s: connected",
2720 			 remotehost);
2721 	setproctitle("%s", proctitle);
2722 #endif /* SETPROCTITLE */
2723 
2724 	if (logging) {
2725 #ifdef VIRTUAL_HOSTING
2726 		if (thishost != firsthost)
2727 			syslog(LOG_INFO, "connection from %s (%s) to %s",
2728 			       remotehost, who_name, hostname);
2729 		else
2730 #endif
2731 			syslog(LOG_INFO, "connection from %s (%s)",
2732 			       remotehost, who_name);
2733 	}
2734 }
2735 
2736 /*
2737  * Record logout in wtmp file
2738  * and exit with supplied status.
2739  */
2740 void
2741 dologout(int status)
2742 {
2743 
2744 	if (logged_in && dowtmp) {
2745 		(void) seteuid(0);
2746 #ifdef		LOGIN_CAP
2747  	        setusercontext(NULL, getpwuid(0), 0, LOGIN_SETALL & ~(LOGIN_SETLOGIN |
2748 		       LOGIN_SETUSER | LOGIN_SETGROUP | LOGIN_SETPATH |
2749 		       LOGIN_SETENV));
2750 #endif
2751 		ftpd_logwtmp(wtmpid, NULL, NULL);
2752 	}
2753 	/* beware of flushing buffers after a SIGPIPE */
2754 	_exit(status);
2755 }
2756 
2757 static void
2758 sigurg(int signo)
2759 {
2760 
2761 	recvurg = 1;
2762 }
2763 
2764 static void
2765 maskurg(int flag)
2766 {
2767 	int oerrno;
2768 	sigset_t sset;
2769 
2770 	if (!transflag) {
2771 		syslog(LOG_ERR, "Internal: maskurg() while no transfer");
2772 		return;
2773 	}
2774 	oerrno = errno;
2775 	sigemptyset(&sset);
2776 	sigaddset(&sset, SIGURG);
2777 	sigprocmask(flag ? SIG_BLOCK : SIG_UNBLOCK, &sset, NULL);
2778 	errno = oerrno;
2779 }
2780 
2781 static void
2782 flagxfer(int flag)
2783 {
2784 
2785 	if (flag) {
2786 		if (transflag)
2787 			syslog(LOG_ERR, "Internal: flagxfer(1): "
2788 					"transfer already under way");
2789 		transflag = 1;
2790 		maskurg(0);
2791 		recvurg = 0;
2792 	} else {
2793 		if (!transflag)
2794 			syslog(LOG_ERR, "Internal: flagxfer(0): "
2795 					"no active transfer");
2796 		maskurg(1);
2797 		transflag = 0;
2798 	}
2799 }
2800 
2801 /*
2802  * Returns 0 if OK to resume or -1 if abort requested.
2803  */
2804 static int
2805 myoob(void)
2806 {
2807 	char *cp;
2808 	int ret;
2809 
2810 	if (!transflag) {
2811 		syslog(LOG_ERR, "Internal: myoob() while no transfer");
2812 		return (0);
2813 	}
2814 	cp = tmpline;
2815 	ret = get_line(cp, 7, stdin);
2816 	if (ret == -1) {
2817 		reply(221, "You could at least say goodbye.");
2818 		dologout(0);
2819 	} else if (ret == -2) {
2820 		/* Ignore truncated command. */
2821 		return (0);
2822 	}
2823 	upper(cp);
2824 	if (strcmp(cp, "ABOR\r\n") == 0) {
2825 		tmpline[0] = '\0';
2826 		reply(426, "Transfer aborted. Data connection closed.");
2827 		reply(226, "Abort successful.");
2828 		return (-1);
2829 	}
2830 	if (strcmp(cp, "STAT\r\n") == 0) {
2831 		tmpline[0] = '\0';
2832 		if (file_size != -1)
2833 			reply(213, "Status: %jd of %jd bytes transferred.",
2834 				   (intmax_t)byte_count, (intmax_t)file_size);
2835 		else
2836 			reply(213, "Status: %jd bytes transferred.",
2837 				   (intmax_t)byte_count);
2838 	}
2839 	return (0);
2840 }
2841 
2842 /*
2843  * Note: a response of 425 is not mentioned as a possible response to
2844  *	the PASV command in RFC959. However, it has been blessed as
2845  *	a legitimate response by Jon Postel in a telephone conversation
2846  *	with Rick Adams on 25 Jan 89.
2847  */
2848 void
2849 passive(void)
2850 {
2851 	socklen_t len;
2852 	int on;
2853 	char *p, *a;
2854 
2855 	if (pdata >= 0)		/* close old port if one set */
2856 		close(pdata);
2857 
2858 	pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
2859 	if (pdata < 0) {
2860 		perror_reply(425, "Can't open passive connection");
2861 		return;
2862 	}
2863 	on = 1;
2864 	if (setsockopt(pdata, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
2865 		syslog(LOG_WARNING, "pdata setsockopt (SO_REUSEADDR): %m");
2866 
2867 	(void) seteuid(0);
2868 
2869 #ifdef IP_PORTRANGE
2870 	if (ctrl_addr.su_family == AF_INET) {
2871 	    on = restricted_data_ports ? IP_PORTRANGE_HIGH
2872 				       : IP_PORTRANGE_DEFAULT;
2873 
2874 	    if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE,
2875 			    &on, sizeof(on)) < 0)
2876 		    goto pasv_error;
2877 	}
2878 #endif
2879 #ifdef IPV6_PORTRANGE
2880 	if (ctrl_addr.su_family == AF_INET6) {
2881 	    on = restricted_data_ports ? IPV6_PORTRANGE_HIGH
2882 				       : IPV6_PORTRANGE_DEFAULT;
2883 
2884 	    if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE,
2885 			    &on, sizeof(on)) < 0)
2886 		    goto pasv_error;
2887 	}
2888 #endif
2889 
2890 	pasv_addr = ctrl_addr;
2891 	pasv_addr.su_port = 0;
2892 	if (bind(pdata, (struct sockaddr *)&pasv_addr, pasv_addr.su_len) < 0)
2893 		goto pasv_error;
2894 
2895 	(void) seteuid(pw->pw_uid);
2896 
2897 	len = sizeof(pasv_addr);
2898 	if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0)
2899 		goto pasv_error;
2900 	if (listen(pdata, 1) < 0)
2901 		goto pasv_error;
2902 	if (pasv_addr.su_family == AF_INET)
2903 		a = (char *) &pasv_addr.su_sin.sin_addr;
2904 	else if (pasv_addr.su_family == AF_INET6 &&
2905 		 IN6_IS_ADDR_V4MAPPED(&pasv_addr.su_sin6.sin6_addr))
2906 		a = (char *) &pasv_addr.su_sin6.sin6_addr.s6_addr[12];
2907 	else
2908 		goto pasv_error;
2909 
2910 	p = (char *) &pasv_addr.su_port;
2911 
2912 #define UC(b) (((int) b) & 0xff)
2913 
2914 	reply(227, "Entering Passive Mode (%d,%d,%d,%d,%d,%d)", UC(a[0]),
2915 		UC(a[1]), UC(a[2]), UC(a[3]), UC(p[0]), UC(p[1]));
2916 	return;
2917 
2918 pasv_error:
2919 	(void) seteuid(pw->pw_uid);
2920 	(void) close(pdata);
2921 	pdata = -1;
2922 	perror_reply(425, "Can't open passive connection");
2923 	return;
2924 }
2925 
2926 /*
2927  * Long Passive defined in RFC 1639.
2928  *     228 Entering Long Passive Mode
2929  *         (af, hal, h1, h2, h3,..., pal, p1, p2...)
2930  */
2931 
2932 void
2933 long_passive(char *cmd, int pf)
2934 {
2935 	socklen_t len;
2936 	int on;
2937 	char *p, *a;
2938 
2939 	if (pdata >= 0)		/* close old port if one set */
2940 		close(pdata);
2941 
2942 	if (pf != PF_UNSPEC) {
2943 		if (ctrl_addr.su_family != pf) {
2944 			switch (ctrl_addr.su_family) {
2945 			case AF_INET:
2946 				pf = 1;
2947 				break;
2948 			case AF_INET6:
2949 				pf = 2;
2950 				break;
2951 			default:
2952 				pf = 0;
2953 				break;
2954 			}
2955 			/*
2956 			 * XXX
2957 			 * only EPRT/EPSV ready clients will understand this
2958 			 */
2959 			if (strcmp(cmd, "EPSV") == 0 && pf) {
2960 				reply(522, "Network protocol mismatch, "
2961 					"use (%d)", pf);
2962 			} else
2963 				reply(501, "Network protocol mismatch."); /*XXX*/
2964 
2965 			return;
2966 		}
2967 	}
2968 
2969 	pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
2970 	if (pdata < 0) {
2971 		perror_reply(425, "Can't open passive connection");
2972 		return;
2973 	}
2974 	on = 1;
2975 	if (setsockopt(pdata, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
2976 		syslog(LOG_WARNING, "pdata setsockopt (SO_REUSEADDR): %m");
2977 
2978 	(void) seteuid(0);
2979 
2980 	pasv_addr = ctrl_addr;
2981 	pasv_addr.su_port = 0;
2982 	len = pasv_addr.su_len;
2983 
2984 #ifdef IP_PORTRANGE
2985 	if (ctrl_addr.su_family == AF_INET) {
2986 	    on = restricted_data_ports ? IP_PORTRANGE_HIGH
2987 				       : IP_PORTRANGE_DEFAULT;
2988 
2989 	    if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE,
2990 			    &on, sizeof(on)) < 0)
2991 		    goto pasv_error;
2992 	}
2993 #endif
2994 #ifdef IPV6_PORTRANGE
2995 	if (ctrl_addr.su_family == AF_INET6) {
2996 	    on = restricted_data_ports ? IPV6_PORTRANGE_HIGH
2997 				       : IPV6_PORTRANGE_DEFAULT;
2998 
2999 	    if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE,
3000 			    &on, sizeof(on)) < 0)
3001 		    goto pasv_error;
3002 	}
3003 #endif
3004 
3005 	if (bind(pdata, (struct sockaddr *)&pasv_addr, len) < 0)
3006 		goto pasv_error;
3007 
3008 	(void) seteuid(pw->pw_uid);
3009 
3010 	if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0)
3011 		goto pasv_error;
3012 	if (listen(pdata, 1) < 0)
3013 		goto pasv_error;
3014 
3015 #define UC(b) (((int) b) & 0xff)
3016 
3017 	if (strcmp(cmd, "LPSV") == 0) {
3018 		p = (char *)&pasv_addr.su_port;
3019 		switch (pasv_addr.su_family) {
3020 		case AF_INET:
3021 			a = (char *) &pasv_addr.su_sin.sin_addr;
3022 		v4_reply:
3023 			reply(228,
3024 "Entering Long Passive Mode (%d,%d,%d,%d,%d,%d,%d,%d,%d)",
3025 			      4, 4, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
3026 			      2, UC(p[0]), UC(p[1]));
3027 			return;
3028 		case AF_INET6:
3029 			if (IN6_IS_ADDR_V4MAPPED(&pasv_addr.su_sin6.sin6_addr)) {
3030 				a = (char *) &pasv_addr.su_sin6.sin6_addr.s6_addr[12];
3031 				goto v4_reply;
3032 			}
3033 			a = (char *) &pasv_addr.su_sin6.sin6_addr;
3034 			reply(228,
3035 "Entering Long Passive Mode "
3036 "(%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d)",
3037 			      6, 16, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
3038 			      UC(a[4]), UC(a[5]), UC(a[6]), UC(a[7]),
3039 			      UC(a[8]), UC(a[9]), UC(a[10]), UC(a[11]),
3040 			      UC(a[12]), UC(a[13]), UC(a[14]), UC(a[15]),
3041 			      2, UC(p[0]), UC(p[1]));
3042 			return;
3043 		}
3044 	} else if (strcmp(cmd, "EPSV") == 0) {
3045 		switch (pasv_addr.su_family) {
3046 		case AF_INET:
3047 		case AF_INET6:
3048 			reply(229, "Entering Extended Passive Mode (|||%d|)",
3049 				ntohs(pasv_addr.su_port));
3050 			return;
3051 		}
3052 	} else {
3053 		/* more proper error code? */
3054 	}
3055 
3056 pasv_error:
3057 	(void) seteuid(pw->pw_uid);
3058 	(void) close(pdata);
3059 	pdata = -1;
3060 	perror_reply(425, "Can't open passive connection");
3061 	return;
3062 }
3063 
3064 /*
3065  * Generate unique name for file with basename "local"
3066  * and open the file in order to avoid possible races.
3067  * Try "local" first, then "local.1", "local.2" etc, up to "local.99".
3068  * Return descriptor to the file, set "name" to its name.
3069  *
3070  * Generates failure reply on error.
3071  */
3072 static int
3073 guniquefd(char *local, char **name)
3074 {
3075 	static char new[MAXPATHLEN];
3076 	struct stat st;
3077 	char *cp;
3078 	int count;
3079 	int fd;
3080 
3081 	cp = strrchr(local, '/');
3082 	if (cp)
3083 		*cp = '\0';
3084 	if (stat(cp ? local : ".", &st) < 0) {
3085 		perror_reply(553, cp ? local : ".");
3086 		return (-1);
3087 	}
3088 	if (cp) {
3089 		/*
3090 		 * Let not overwrite dirname with counter suffix.
3091 		 * -4 is for /nn\0
3092 		 * In this extreme case dot won't be put in front of suffix.
3093 		 */
3094 		if (strlen(local) > sizeof(new) - 4) {
3095 			reply(553, "Pathname too long.");
3096 			return (-1);
3097 		}
3098 		*cp = '/';
3099 	}
3100 	/* -4 is for the .nn<null> we put on the end below */
3101 	(void) snprintf(new, sizeof(new) - 4, "%s", local);
3102 	cp = new + strlen(new);
3103 	/*
3104 	 * Don't generate dotfile unless requested explicitly.
3105 	 * This covers the case when basename gets truncated off
3106 	 * by buffer size.
3107 	 */
3108 	if (cp > new && cp[-1] != '/')
3109 		*cp++ = '.';
3110 	for (count = 0; count < 100; count++) {
3111 		/* At count 0 try unmodified name */
3112 		if (count)
3113 			(void)sprintf(cp, "%d", count);
3114 		if ((fd = open(count ? new : local,
3115 		    O_RDWR | O_CREAT | O_EXCL, 0666)) >= 0) {
3116 			*name = count ? new : local;
3117 			return (fd);
3118 		}
3119 		if (errno != EEXIST) {
3120 			perror_reply(553, count ? new : local);
3121 			return (-1);
3122 		}
3123 	}
3124 	reply(452, "Unique file name cannot be created.");
3125 	return (-1);
3126 }
3127 
3128 /*
3129  * Format and send reply containing system error number.
3130  */
3131 void
3132 perror_reply(int code, char *string)
3133 {
3134 
3135 	reply(code, "%s: %s.", string, strerror(errno));
3136 }
3137 
3138 static char *onefile[] = {
3139 	"",
3140 	0
3141 };
3142 
3143 void
3144 send_file_list(char *whichf)
3145 {
3146 	struct stat st;
3147 	DIR *dirp = NULL;
3148 	struct dirent *dir;
3149 	FILE *dout = NULL;
3150 	char **dirlist, *dirname;
3151 	int simple = 0;
3152 	int freeglob = 0;
3153 	glob_t gl;
3154 
3155 	if (strpbrk(whichf, "~{[*?") != NULL) {
3156 		int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE;
3157 
3158 		memset(&gl, 0, sizeof(gl));
3159 		gl.gl_matchc = MAXGLOBARGS;
3160 		flags |= GLOB_LIMIT;
3161 		freeglob = 1;
3162 		if (glob(whichf, flags, 0, &gl)) {
3163 			reply(550, "No matching files found.");
3164 			goto out;
3165 		} else if (gl.gl_pathc == 0) {
3166 			errno = ENOENT;
3167 			perror_reply(550, whichf);
3168 			goto out;
3169 		}
3170 		dirlist = gl.gl_pathv;
3171 	} else {
3172 		onefile[0] = whichf;
3173 		dirlist = onefile;
3174 		simple = 1;
3175 	}
3176 
3177 	while ((dirname = *dirlist++)) {
3178 		if (stat(dirname, &st) < 0) {
3179 			/*
3180 			 * If user typed "ls -l", etc, and the client
3181 			 * used NLST, do what the user meant.
3182 			 */
3183 			if (dirname[0] == '-' && *dirlist == NULL &&
3184 			    dout == NULL)
3185 				retrieve(_PATH_LS " %s", dirname);
3186 			else
3187 				perror_reply(550, whichf);
3188 			goto out;
3189 		}
3190 
3191 		if (S_ISREG(st.st_mode)) {
3192 			if (dout == NULL) {
3193 				dout = dataconn("file list", -1, "w");
3194 				if (dout == NULL)
3195 					goto out;
3196 				STARTXFER;
3197 			}
3198 			START_UNSAFE;
3199 			fprintf(dout, "%s%s\n", dirname,
3200 				type == TYPE_A ? "\r" : "");
3201 			END_UNSAFE;
3202 			if (ferror(dout))
3203 				goto data_err;
3204 			byte_count += strlen(dirname) +
3205 				      (type == TYPE_A ? 2 : 1);
3206 			CHECKOOB(goto abrt);
3207 			continue;
3208 		} else if (!S_ISDIR(st.st_mode))
3209 			continue;
3210 
3211 		if ((dirp = opendir(dirname)) == NULL)
3212 			continue;
3213 
3214 		while ((dir = readdir(dirp)) != NULL) {
3215 			char nbuf[MAXPATHLEN];
3216 
3217 			CHECKOOB(goto abrt);
3218 
3219 			if (dir->d_name[0] == '.' && dir->d_namlen == 1)
3220 				continue;
3221 			if (dir->d_name[0] == '.' && dir->d_name[1] == '.' &&
3222 			    dir->d_namlen == 2)
3223 				continue;
3224 
3225 			snprintf(nbuf, sizeof(nbuf),
3226 				"%s/%s", dirname, dir->d_name);
3227 
3228 			/*
3229 			 * We have to do a stat to insure it's
3230 			 * not a directory or special file.
3231 			 */
3232 			if (simple || (stat(nbuf, &st) == 0 &&
3233 			    S_ISREG(st.st_mode))) {
3234 				if (dout == NULL) {
3235 					dout = dataconn("file list", -1, "w");
3236 					if (dout == NULL)
3237 						goto out;
3238 					STARTXFER;
3239 				}
3240 				START_UNSAFE;
3241 				if (nbuf[0] == '.' && nbuf[1] == '/')
3242 					fprintf(dout, "%s%s\n", &nbuf[2],
3243 						type == TYPE_A ? "\r" : "");
3244 				else
3245 					fprintf(dout, "%s%s\n", nbuf,
3246 						type == TYPE_A ? "\r" : "");
3247 				END_UNSAFE;
3248 				if (ferror(dout))
3249 					goto data_err;
3250 				byte_count += strlen(nbuf) +
3251 					      (type == TYPE_A ? 2 : 1);
3252 				CHECKOOB(goto abrt);
3253 			}
3254 		}
3255 		(void) closedir(dirp);
3256 		dirp = NULL;
3257 	}
3258 
3259 	if (dout == NULL)
3260 		reply(550, "No files found.");
3261 	else if (ferror(dout))
3262 data_err:	perror_reply(550, "Data connection");
3263 	else
3264 		reply(226, "Transfer complete.");
3265 out:
3266 	if (dout) {
3267 		ENDXFER;
3268 abrt:
3269 		(void) fclose(dout);
3270 		data = -1;
3271 		pdata = -1;
3272 	}
3273 	if (dirp)
3274 		(void) closedir(dirp);
3275 	if (freeglob) {
3276 		freeglob = 0;
3277 		globfree(&gl);
3278 	}
3279 }
3280 
3281 void
3282 reapchild(int signo)
3283 {
3284 	while (waitpid(-1, NULL, WNOHANG) > 0);
3285 }
3286 
3287 static void
3288 appendf(char **strp, char *fmt, ...)
3289 {
3290 	va_list ap;
3291 	char *ostr, *p;
3292 
3293 	va_start(ap, fmt);
3294 	vasprintf(&p, fmt, ap);
3295 	va_end(ap);
3296 	if (p == NULL)
3297 		fatalerror("Ran out of memory.");
3298 	if (*strp == NULL)
3299 		*strp = p;
3300 	else {
3301 		ostr = *strp;
3302 		asprintf(strp, "%s%s", ostr, p);
3303 		if (*strp == NULL)
3304 			fatalerror("Ran out of memory.");
3305 		free(ostr);
3306 	}
3307 }
3308 
3309 static void
3310 logcmd(char *cmd, char *file1, char *file2, off_t cnt)
3311 {
3312 	char *msg = NULL;
3313 	char wd[MAXPATHLEN + 1];
3314 
3315 	if (logging <= 1)
3316 		return;
3317 
3318 	if (getcwd(wd, sizeof(wd) - 1) == NULL)
3319 		strcpy(wd, strerror(errno));
3320 
3321 	appendf(&msg, "%s", cmd);
3322 	if (file1)
3323 		appendf(&msg, " %s", file1);
3324 	if (file2)
3325 		appendf(&msg, " %s", file2);
3326 	if (cnt >= 0)
3327 		appendf(&msg, " = %jd bytes", (intmax_t)cnt);
3328 	appendf(&msg, " (wd: %s", wd);
3329 	if (guest || dochroot)
3330 		appendf(&msg, "; chrooted");
3331 	appendf(&msg, ")");
3332 	syslog(LOG_INFO, "%s", msg);
3333 	free(msg);
3334 }
3335 
3336 static void
3337 logxfer(char *name, off_t size, time_t start)
3338 {
3339 	char buf[MAXPATHLEN + 1024];
3340 	char path[MAXPATHLEN + 1];
3341 	time_t now;
3342 
3343 	if (statfd >= 0) {
3344 		time(&now);
3345 		if (realpath(name, path) == NULL) {
3346 			syslog(LOG_NOTICE, "realpath failed on %s: %m", path);
3347 			return;
3348 		}
3349 		snprintf(buf, sizeof(buf), "%.20s!%s!%s!%s!%jd!%ld\n",
3350 			ctime(&now)+4, ident, remotehost,
3351 			path, (intmax_t)size,
3352 			(long)(now - start + (now == start)));
3353 		write(statfd, buf, strlen(buf));
3354 	}
3355 }
3356 
3357 static char *
3358 doublequote(char *s)
3359 {
3360 	int n;
3361 	char *p, *s2;
3362 
3363 	for (p = s, n = 0; *p; p++)
3364 		if (*p == '"')
3365 			n++;
3366 
3367 	if ((s2 = malloc(p - s + n + 1)) == NULL)
3368 		return (NULL);
3369 
3370 	for (p = s2; *s; s++, p++) {
3371 		if ((*p = *s) == '"')
3372 			*(++p) = '"';
3373 	}
3374 	*p = '\0';
3375 
3376 	return (s2);
3377 }
3378 
3379 /* setup server socket for specified address family */
3380 /* if af is PF_UNSPEC more than one socket may be returned */
3381 /* the returned list is dynamically allocated, so caller needs to free it */
3382 static int *
3383 socksetup(int af, char *bindname, const char *bindport)
3384 {
3385 	struct addrinfo hints, *res, *r;
3386 	int error, maxs, *s, *socks;
3387 	const int on = 1;
3388 
3389 	memset(&hints, 0, sizeof(hints));
3390 	hints.ai_flags = AI_PASSIVE;
3391 	hints.ai_family = af;
3392 	hints.ai_socktype = SOCK_STREAM;
3393 	error = getaddrinfo(bindname, bindport, &hints, &res);
3394 	if (error) {
3395 		syslog(LOG_ERR, "%s", gai_strerror(error));
3396 		if (error == EAI_SYSTEM)
3397 			syslog(LOG_ERR, "%s", strerror(errno));
3398 		return NULL;
3399 	}
3400 
3401 	/* Count max number of sockets we may open */
3402 	for (maxs = 0, r = res; r; r = r->ai_next, maxs++)
3403 		;
3404 	socks = malloc((maxs + 1) * sizeof(int));
3405 	if (!socks) {
3406 		freeaddrinfo(res);
3407 		syslog(LOG_ERR, "couldn't allocate memory for sockets");
3408 		return NULL;
3409 	}
3410 
3411 	*socks = 0;   /* num of sockets counter at start of array */
3412 	s = socks + 1;
3413 	for (r = res; r; r = r->ai_next) {
3414 		*s = socket(r->ai_family, r->ai_socktype, r->ai_protocol);
3415 		if (*s < 0) {
3416 			syslog(LOG_DEBUG, "control socket: %m");
3417 			continue;
3418 		}
3419 		if (setsockopt(*s, SOL_SOCKET, SO_REUSEADDR,
3420 		    &on, sizeof(on)) < 0)
3421 			syslog(LOG_WARNING,
3422 			    "control setsockopt (SO_REUSEADDR): %m");
3423 		if (r->ai_family == AF_INET6) {
3424 			if (setsockopt(*s, IPPROTO_IPV6, IPV6_V6ONLY,
3425 			    &on, sizeof(on)) < 0)
3426 				syslog(LOG_WARNING,
3427 				    "control setsockopt (IPV6_V6ONLY): %m");
3428 		}
3429 		if (bind(*s, r->ai_addr, r->ai_addrlen) < 0) {
3430 			syslog(LOG_DEBUG, "control bind: %m");
3431 			close(*s);
3432 			continue;
3433 		}
3434 		(*socks)++;
3435 		s++;
3436 	}
3437 
3438 	if (res)
3439 		freeaddrinfo(res);
3440 
3441 	if (*socks == 0) {
3442 		syslog(LOG_ERR, "control socket: Couldn't bind to any socket");
3443 		free(socks);
3444 		return NULL;
3445 	}
3446 	return(socks);
3447 }
3448