xref: /freebsd/libexec/ftpd/ftpd.c (revision cfd6422a5217410fbd66f7a7a8a64d9d85e61229)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #if 0
33 #ifndef lint
34 static char copyright[] =
35 "@(#) Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994\n\
36 	The Regents of the University of California.  All rights reserved.\n";
37 #endif /* not lint */
38 #endif
39 
40 #ifndef lint
41 #if 0
42 static char sccsid[] = "@(#)ftpd.c	8.4 (Berkeley) 4/16/94";
43 #endif
44 #endif /* not lint */
45 
46 #include <sys/cdefs.h>
47 __FBSDID("$FreeBSD$");
48 
49 /*
50  * FTP server.
51  */
52 #include <sys/param.h>
53 #include <sys/ioctl.h>
54 #include <sys/mman.h>
55 #include <sys/socket.h>
56 #include <sys/stat.h>
57 #include <sys/time.h>
58 #include <sys/wait.h>
59 
60 #include <netinet/in.h>
61 #include <netinet/in_systm.h>
62 #include <netinet/ip.h>
63 #include <netinet/tcp.h>
64 
65 #define	FTP_NAMES
66 #include <arpa/ftp.h>
67 #include <arpa/inet.h>
68 #include <arpa/telnet.h>
69 
70 #include <ctype.h>
71 #include <dirent.h>
72 #include <err.h>
73 #include <errno.h>
74 #include <fcntl.h>
75 #include <glob.h>
76 #include <limits.h>
77 #include <netdb.h>
78 #include <pwd.h>
79 #include <grp.h>
80 #include <opie.h>
81 #include <signal.h>
82 #include <stdint.h>
83 #include <stdio.h>
84 #include <stdlib.h>
85 #include <string.h>
86 #include <syslog.h>
87 #include <time.h>
88 #include <unistd.h>
89 #include <libutil.h>
90 #ifdef	LOGIN_CAP
91 #include <login_cap.h>
92 #endif
93 
94 #ifdef USE_PAM
95 #include <security/pam_appl.h>
96 #endif
97 
98 #include "blacklist_client.h"
99 #include "pathnames.h"
100 #include "extern.h"
101 
102 #include <stdarg.h>
103 
104 static char version[] = "Version 6.00LS";
105 #undef main
106 
107 union sockunion ctrl_addr;
108 union sockunion data_source;
109 union sockunion data_dest;
110 union sockunion his_addr;
111 union sockunion pasv_addr;
112 
113 int	daemon_mode;
114 int	data;
115 int	dataport;
116 int	hostinfo = 1;	/* print host-specific info in messages */
117 int	logged_in;
118 struct	passwd *pw;
119 char	*homedir;
120 int	ftpdebug;
121 int	timeout = 900;    /* timeout after 15 minutes of inactivity */
122 int	maxtimeout = 7200;/* don't allow idle time to be set beyond 2 hours */
123 int	logging;
124 int	restricted_data_ports = 1;
125 int	paranoid = 1;	  /* be extra careful about security */
126 int	anon_only = 0;    /* Only anonymous ftp allowed */
127 int	assumeutf8 = 0;   /* Assume that server file names are in UTF-8 */
128 int	guest;
129 int	dochroot;
130 char	*chrootdir;
131 int	dowtmp = 1;
132 int	stats;
133 int	statfd = -1;
134 int	type;
135 int	form;
136 int	stru;			/* avoid C keyword */
137 int	mode;
138 int	usedefault = 1;		/* for data transfers */
139 int	pdata = -1;		/* for passive mode */
140 int	readonly = 0;		/* Server is in readonly mode.	*/
141 int	noepsv = 0;		/* EPSV command is disabled.	*/
142 int	noretr = 0;		/* RETR command is disabled.	*/
143 int	noguestretr = 0;	/* RETR command is disabled for anon users. */
144 int	noguestmkd = 0;		/* MKD command is disabled for anon users. */
145 int	noguestmod = 1;		/* anon users may not modify existing files. */
146 int	use_blacklist = 0;
147 
148 off_t	file_size;
149 off_t	byte_count;
150 #if !defined(CMASK) || CMASK == 0
151 #undef CMASK
152 #define CMASK 027
153 #endif
154 int	defumask = CMASK;		/* default umask value */
155 char	tmpline[7];
156 char	*hostname;
157 int	epsvall = 0;
158 
159 #ifdef VIRTUAL_HOSTING
160 char	*ftpuser;
161 
162 static struct ftphost {
163 	struct ftphost	*next;
164 	struct addrinfo *hostinfo;
165 	char		*hostname;
166 	char		*anonuser;
167 	char		*statfile;
168 	char		*welcome;
169 	char		*loginmsg;
170 } *thishost, *firsthost;
171 
172 #endif
173 char	remotehost[NI_MAXHOST];
174 char	*ident = NULL;
175 
176 static char	wtmpid[20];
177 
178 #ifdef USE_PAM
179 static int	auth_pam(struct passwd**, const char*);
180 pam_handle_t	*pamh = NULL;
181 #endif
182 
183 static struct opie	opiedata;
184 static char		opieprompt[OPIE_CHALLENGE_MAX+1];
185 static int		pwok;
186 
187 char	*pid_file = NULL; /* means default location to pidfile(3) */
188 
189 /*
190  * Limit number of pathnames that glob can return.
191  * A limit of 0 indicates the number of pathnames is unlimited.
192  */
193 #define MAXGLOBARGS	16384
194 #
195 
196 /*
197  * Timeout intervals for retrying connections
198  * to hosts that don't accept PORT cmds.  This
199  * is a kludge, but given the problems with TCP...
200  */
201 #define	SWAITMAX	90	/* wait at most 90 seconds */
202 #define	SWAITINT	5	/* interval between retries */
203 
204 int	swaitmax = SWAITMAX;
205 int	swaitint = SWAITINT;
206 
207 #ifdef SETPROCTITLE
208 #ifdef OLD_SETPROCTITLE
209 char	**Argv = NULL;		/* pointer to argument vector */
210 char	*LastArgv = NULL;	/* end of argv */
211 #endif /* OLD_SETPROCTITLE */
212 char	proctitle[LINE_MAX];	/* initial part of title */
213 #endif /* SETPROCTITLE */
214 
215 #define LOGCMD(cmd, file)		logcmd((cmd), (file), NULL, -1)
216 #define LOGCMD2(cmd, file1, file2)	logcmd((cmd), (file1), (file2), -1)
217 #define LOGBYTES(cmd, file, cnt)	logcmd((cmd), (file), NULL, (cnt))
218 
219 static	volatile sig_atomic_t recvurg;
220 static	int transflag;		/* NB: for debugging only */
221 
222 #define STARTXFER	flagxfer(1)
223 #define ENDXFER		flagxfer(0)
224 
225 #define START_UNSAFE	maskurg(1)
226 #define END_UNSAFE	maskurg(0)
227 
228 /* It's OK to put an `else' clause after this macro. */
229 #define CHECKOOB(action)						\
230 	if (recvurg) {							\
231 		recvurg = 0;						\
232 		if (myoob()) {						\
233 			ENDXFER;					\
234 			action;						\
235 		}							\
236 	}
237 
238 #ifdef VIRTUAL_HOSTING
239 static void	 inithosts(int);
240 static void	 selecthost(union sockunion *);
241 #endif
242 static void	 ack(char *);
243 static void	 sigurg(int);
244 static void	 maskurg(int);
245 static void	 flagxfer(int);
246 static int	 myoob(void);
247 static int	 checkuser(char *, char *, int, char **, int *);
248 static FILE	*dataconn(char *, off_t, char *);
249 static void	 dolog(struct sockaddr *);
250 static void	 end_login(void);
251 static FILE	*getdatasock(char *);
252 static int	 guniquefd(char *, char **);
253 static void	 lostconn(int);
254 static void	 sigquit(int);
255 static int	 receive_data(FILE *, FILE *);
256 static int	 send_data(FILE *, FILE *, size_t, off_t, int);
257 static struct passwd *
258 		 sgetpwnam(char *);
259 static char	*sgetsave(char *);
260 static void	 reapchild(int);
261 static void	 appendf(char **, char *, ...) __printflike(2, 3);
262 static void	 logcmd(char *, char *, char *, off_t);
263 static void      logxfer(char *, off_t, time_t);
264 static char	*doublequote(char *);
265 static int	*socksetup(int, char *, const char *);
266 
267 int
268 main(int argc, char *argv[], char **envp)
269 {
270 	socklen_t addrlen;
271 	int ch, on = 1, tos, s = STDIN_FILENO;
272 	char *cp, line[LINE_MAX];
273 	FILE *fd;
274 	char	*bindname = NULL;
275 	const char *bindport = "ftp";
276 	int	family = AF_UNSPEC;
277 	struct sigaction sa;
278 
279 	tzset();		/* in case no timezone database in ~ftp */
280 	sigemptyset(&sa.sa_mask);
281 	sa.sa_flags = SA_RESTART;
282 
283 #ifdef OLD_SETPROCTITLE
284 	/*
285 	 *  Save start and extent of argv for setproctitle.
286 	 */
287 	Argv = argv;
288 	while (*envp)
289 		envp++;
290 	LastArgv = envp[-1] + strlen(envp[-1]);
291 #endif /* OLD_SETPROCTITLE */
292 
293 	/*
294 	 * Prevent diagnostic messages from appearing on stderr.
295 	 * We run as a daemon or from inetd; in both cases, there's
296 	 * more reason in logging to syslog.
297 	 */
298 	(void) freopen(_PATH_DEVNULL, "w", stderr);
299 	opterr = 0;
300 
301 	/*
302 	 * LOG_NDELAY sets up the logging connection immediately,
303 	 * necessary for anonymous ftp's that chroot and can't do it later.
304 	 */
305 	openlog("ftpd", LOG_PID | LOG_NDELAY, LOG_FTP);
306 
307 	while ((ch = getopt(argc, argv,
308 	                    "468a:ABdDEhlmMoOp:P:rRSt:T:u:UvW")) != -1) {
309 		switch (ch) {
310 		case '4':
311 			family = (family == AF_INET6) ? AF_UNSPEC : AF_INET;
312 			break;
313 
314 		case '6':
315 			family = (family == AF_INET) ? AF_UNSPEC : AF_INET6;
316 			break;
317 
318 		case '8':
319 			assumeutf8 = 1;
320 			break;
321 
322 		case 'a':
323 			bindname = optarg;
324 			break;
325 
326 		case 'A':
327 			anon_only = 1;
328 			break;
329 
330 		case 'B':
331 #ifdef USE_BLACKLIST
332 			use_blacklist = 1;
333 #else
334 			syslog(LOG_WARNING, "not compiled with USE_BLACKLIST support");
335 #endif
336 			break;
337 
338 		case 'd':
339 			ftpdebug++;
340 			break;
341 
342 		case 'D':
343 			daemon_mode++;
344 			break;
345 
346 		case 'E':
347 			noepsv = 1;
348 			break;
349 
350 		case 'h':
351 			hostinfo = 0;
352 			break;
353 
354 		case 'l':
355 			logging++;	/* > 1 == extra logging */
356 			break;
357 
358 		case 'm':
359 			noguestmod = 0;
360 			break;
361 
362 		case 'M':
363 			noguestmkd = 1;
364 			break;
365 
366 		case 'o':
367 			noretr = 1;
368 			break;
369 
370 		case 'O':
371 			noguestretr = 1;
372 			break;
373 
374 		case 'p':
375 			pid_file = optarg;
376 			break;
377 
378 		case 'P':
379 			bindport = optarg;
380 			break;
381 
382 		case 'r':
383 			readonly = 1;
384 			break;
385 
386 		case 'R':
387 			paranoid = 0;
388 			break;
389 
390 		case 'S':
391 			stats++;
392 			break;
393 
394 		case 't':
395 			timeout = atoi(optarg);
396 			if (maxtimeout < timeout)
397 				maxtimeout = timeout;
398 			break;
399 
400 		case 'T':
401 			maxtimeout = atoi(optarg);
402 			if (timeout > maxtimeout)
403 				timeout = maxtimeout;
404 			break;
405 
406 		case 'u':
407 		    {
408 			long val = 0;
409 
410 			val = strtol(optarg, &optarg, 8);
411 			if (*optarg != '\0' || val < 0)
412 				syslog(LOG_WARNING, "bad value for -u");
413 			else
414 				defumask = val;
415 			break;
416 		    }
417 		case 'U':
418 			restricted_data_ports = 0;
419 			break;
420 
421 		case 'v':
422 			ftpdebug++;
423 			break;
424 
425 		case 'W':
426 			dowtmp = 0;
427 			break;
428 
429 		default:
430 			syslog(LOG_WARNING, "unknown flag -%c ignored", optopt);
431 			break;
432 		}
433 	}
434 
435 	/* handle filesize limit gracefully */
436 	sa.sa_handler = SIG_IGN;
437 	(void)sigaction(SIGXFSZ, &sa, NULL);
438 
439 	if (daemon_mode) {
440 		int *ctl_sock, fd, maxfd = -1, nfds, i;
441 		fd_set defreadfds, readfds;
442 		pid_t pid;
443 		struct pidfh *pfh;
444 
445 		if ((pfh = pidfile_open(pid_file, 0600, &pid)) == NULL) {
446 			if (errno == EEXIST) {
447 				syslog(LOG_ERR, "%s already running, pid %d",
448 				       getprogname(), (int)pid);
449 				exit(1);
450 			}
451 			syslog(LOG_WARNING, "pidfile_open: %m");
452 		}
453 
454 		/*
455 		 * Detach from parent.
456 		 */
457 		if (daemon(1, 1) < 0) {
458 			syslog(LOG_ERR, "failed to become a daemon");
459 			exit(1);
460 		}
461 
462 		if (pfh != NULL && pidfile_write(pfh) == -1)
463 			syslog(LOG_WARNING, "pidfile_write: %m");
464 
465 		sa.sa_handler = reapchild;
466 		(void)sigaction(SIGCHLD, &sa, NULL);
467 
468 #ifdef VIRTUAL_HOSTING
469 		inithosts(family);
470 #endif
471 
472 		/*
473 		 * Open a socket, bind it to the FTP port, and start
474 		 * listening.
475 		 */
476 		ctl_sock = socksetup(family, bindname, bindport);
477 		if (ctl_sock == NULL)
478 			exit(1);
479 
480 		FD_ZERO(&defreadfds);
481 		for (i = 1; i <= *ctl_sock; i++) {
482 			FD_SET(ctl_sock[i], &defreadfds);
483 			if (listen(ctl_sock[i], 32) < 0) {
484 				syslog(LOG_ERR, "control listen: %m");
485 				exit(1);
486 			}
487 			if (maxfd < ctl_sock[i])
488 				maxfd = ctl_sock[i];
489 		}
490 
491 		/*
492 		 * Loop forever accepting connection requests and forking off
493 		 * children to handle them.
494 		 */
495 		while (1) {
496 			FD_COPY(&defreadfds, &readfds);
497 			nfds = select(maxfd + 1, &readfds, NULL, NULL, 0);
498 			if (nfds <= 0) {
499 				if (nfds < 0 && errno != EINTR)
500 					syslog(LOG_WARNING, "select: %m");
501 				continue;
502 			}
503 
504 			pid = -1;
505                         for (i = 1; i <= *ctl_sock; i++)
506 				if (FD_ISSET(ctl_sock[i], &readfds)) {
507 					addrlen = sizeof(his_addr);
508 					fd = accept(ctl_sock[i],
509 					    (struct sockaddr *)&his_addr,
510 					    &addrlen);
511 					if (fd == -1) {
512 						syslog(LOG_WARNING,
513 						       "accept: %m");
514 						continue;
515 					}
516 					switch (pid = fork()) {
517 					case 0:
518 						/* child */
519 						(void) dup2(fd, s);
520 						(void) dup2(fd, STDOUT_FILENO);
521 						(void) close(fd);
522 						for (i = 1; i <= *ctl_sock; i++)
523 							close(ctl_sock[i]);
524 						if (pfh != NULL)
525 							pidfile_close(pfh);
526 						goto gotchild;
527 					case -1:
528 						syslog(LOG_WARNING, "fork: %m");
529 						/* FALLTHROUGH */
530 					default:
531 						close(fd);
532 					}
533 				}
534 		}
535 	} else {
536 		addrlen = sizeof(his_addr);
537 		if (getpeername(s, (struct sockaddr *)&his_addr, &addrlen) < 0) {
538 			syslog(LOG_ERR, "getpeername (%s): %m",argv[0]);
539 			exit(1);
540 		}
541 
542 #ifdef VIRTUAL_HOSTING
543 		if (his_addr.su_family == AF_INET6 &&
544 		    IN6_IS_ADDR_V4MAPPED(&his_addr.su_sin6.sin6_addr))
545 			family = AF_INET;
546 		else
547 			family = his_addr.su_family;
548 		inithosts(family);
549 #endif
550 	}
551 
552 gotchild:
553 	sa.sa_handler = SIG_DFL;
554 	(void)sigaction(SIGCHLD, &sa, NULL);
555 
556 	sa.sa_handler = sigurg;
557 	sa.sa_flags = 0;		/* don't restart syscalls for SIGURG */
558 	(void)sigaction(SIGURG, &sa, NULL);
559 
560 	sigfillset(&sa.sa_mask);	/* block all signals in handler */
561 	sa.sa_flags = SA_RESTART;
562 	sa.sa_handler = sigquit;
563 	(void)sigaction(SIGHUP, &sa, NULL);
564 	(void)sigaction(SIGINT, &sa, NULL);
565 	(void)sigaction(SIGQUIT, &sa, NULL);
566 	(void)sigaction(SIGTERM, &sa, NULL);
567 
568 	sa.sa_handler = lostconn;
569 	(void)sigaction(SIGPIPE, &sa, NULL);
570 
571 	addrlen = sizeof(ctrl_addr);
572 	if (getsockname(s, (struct sockaddr *)&ctrl_addr, &addrlen) < 0) {
573 		syslog(LOG_ERR, "getsockname (%s): %m",argv[0]);
574 		exit(1);
575 	}
576 	dataport = ntohs(ctrl_addr.su_port) - 1; /* as per RFC 959 */
577 #ifdef VIRTUAL_HOSTING
578 	/* select our identity from virtual host table */
579 	selecthost(&ctrl_addr);
580 #endif
581 #ifdef IP_TOS
582 	if (ctrl_addr.su_family == AF_INET)
583       {
584 	tos = IPTOS_LOWDELAY;
585 	if (setsockopt(s, IPPROTO_IP, IP_TOS, &tos, sizeof(int)) < 0)
586 		syslog(LOG_WARNING, "control setsockopt (IP_TOS): %m");
587       }
588 #endif
589 	/*
590 	 * Disable Nagle on the control channel so that we don't have to wait
591 	 * for peer's ACK before issuing our next reply.
592 	 */
593 	if (setsockopt(s, IPPROTO_TCP, TCP_NODELAY, &on, sizeof(on)) < 0)
594 		syslog(LOG_WARNING, "control setsockopt (TCP_NODELAY): %m");
595 
596 	data_source.su_port = htons(ntohs(ctrl_addr.su_port) - 1);
597 
598 	(void)snprintf(wtmpid, sizeof(wtmpid), "%xftpd", getpid());
599 
600 	/* Try to handle urgent data inline */
601 #ifdef SO_OOBINLINE
602 	if (setsockopt(s, SOL_SOCKET, SO_OOBINLINE, &on, sizeof(on)) < 0)
603 		syslog(LOG_WARNING, "control setsockopt (SO_OOBINLINE): %m");
604 #endif
605 
606 #ifdef	F_SETOWN
607 	if (fcntl(s, F_SETOWN, getpid()) == -1)
608 		syslog(LOG_ERR, "fcntl F_SETOWN: %m");
609 #endif
610 	dolog((struct sockaddr *)&his_addr);
611 	/*
612 	 * Set up default state
613 	 */
614 	data = -1;
615 	type = TYPE_A;
616 	form = FORM_N;
617 	stru = STRU_F;
618 	mode = MODE_S;
619 	tmpline[0] = '\0';
620 
621 	/* If logins are disabled, print out the message. */
622 	if ((fd = fopen(_PATH_NOLOGIN,"r")) != NULL) {
623 		while (fgets(line, sizeof(line), fd) != NULL) {
624 			if ((cp = strchr(line, '\n')) != NULL)
625 				*cp = '\0';
626 			lreply(530, "%s", line);
627 		}
628 		(void) fflush(stdout);
629 		(void) fclose(fd);
630 		reply(530, "System not available.");
631 		exit(0);
632 	}
633 #ifdef VIRTUAL_HOSTING
634 	fd = fopen(thishost->welcome, "r");
635 #else
636 	fd = fopen(_PATH_FTPWELCOME, "r");
637 #endif
638 	if (fd != NULL) {
639 		while (fgets(line, sizeof(line), fd) != NULL) {
640 			if ((cp = strchr(line, '\n')) != NULL)
641 				*cp = '\0';
642 			lreply(220, "%s", line);
643 		}
644 		(void) fflush(stdout);
645 		(void) fclose(fd);
646 		/* reply(220,) must follow */
647 	}
648 #ifndef VIRTUAL_HOSTING
649 	if ((hostname = malloc(MAXHOSTNAMELEN)) == NULL)
650 		fatalerror("Ran out of memory.");
651 	if (gethostname(hostname, MAXHOSTNAMELEN - 1) < 0)
652 		hostname[0] = '\0';
653 	hostname[MAXHOSTNAMELEN - 1] = '\0';
654 #endif
655 	if (hostinfo)
656 		reply(220, "%s FTP server (%s) ready.", hostname, version);
657 	else
658 		reply(220, "FTP server ready.");
659 	BLACKLIST_INIT();
660 	for (;;)
661 		(void) yyparse();
662 	/* NOTREACHED */
663 }
664 
665 static void
666 lostconn(int signo)
667 {
668 
669 	if (ftpdebug)
670 		syslog(LOG_DEBUG, "lost connection");
671 	dologout(1);
672 }
673 
674 static void
675 sigquit(int signo)
676 {
677 
678 	syslog(LOG_ERR, "got signal %d", signo);
679 	dologout(1);
680 }
681 
682 #ifdef VIRTUAL_HOSTING
683 /*
684  * read in virtual host tables (if they exist)
685  */
686 
687 static void
688 inithosts(int family)
689 {
690 	int insert;
691 	size_t len;
692 	FILE *fp;
693 	char *cp, *mp, *line;
694 	char *hostname;
695 	char *vhost, *anonuser, *statfile, *welcome, *loginmsg;
696 	struct ftphost *hrp, *lhrp;
697 	struct addrinfo hints, *res, *ai;
698 
699 	/*
700 	 * Fill in the default host information
701 	 */
702 	if ((hostname = malloc(MAXHOSTNAMELEN)) == NULL)
703 		fatalerror("Ran out of memory.");
704 	if (gethostname(hostname, MAXHOSTNAMELEN - 1) < 0)
705 		hostname[0] = '\0';
706 	hostname[MAXHOSTNAMELEN - 1] = '\0';
707 	if ((hrp = malloc(sizeof(struct ftphost))) == NULL)
708 		fatalerror("Ran out of memory.");
709 	hrp->hostname = hostname;
710 	hrp->hostinfo = NULL;
711 
712 	memset(&hints, 0, sizeof(hints));
713 	hints.ai_flags = AI_PASSIVE;
714 	hints.ai_family = family;
715 	hints.ai_socktype = SOCK_STREAM;
716 	if (getaddrinfo(hrp->hostname, NULL, &hints, &res) == 0)
717 		hrp->hostinfo = res;
718 	hrp->statfile = _PATH_FTPDSTATFILE;
719 	hrp->welcome  = _PATH_FTPWELCOME;
720 	hrp->loginmsg = _PATH_FTPLOGINMESG;
721 	hrp->anonuser = "ftp";
722 	hrp->next = NULL;
723 	thishost = firsthost = lhrp = hrp;
724 	if ((fp = fopen(_PATH_FTPHOSTS, "r")) != NULL) {
725 		int addrsize, gothost;
726 		void *addr;
727 		struct hostent *hp;
728 
729 		while ((line = fgetln(fp, &len)) != NULL) {
730 			int	i, hp_error;
731 
732 			/* skip comments */
733 			if (line[0] == '#')
734 				continue;
735 			if (line[len - 1] == '\n') {
736 				line[len - 1] = '\0';
737 				mp = NULL;
738 			} else {
739 				if ((mp = malloc(len + 1)) == NULL)
740 					fatalerror("Ran out of memory.");
741 				memcpy(mp, line, len);
742 				mp[len] = '\0';
743 				line = mp;
744 			}
745 			cp = strtok(line, " \t");
746 			/* skip empty lines */
747 			if (cp == NULL)
748 				goto nextline;
749 			vhost = cp;
750 
751 			/* set defaults */
752 			anonuser = "ftp";
753 			statfile = _PATH_FTPDSTATFILE;
754 			welcome  = _PATH_FTPWELCOME;
755 			loginmsg = _PATH_FTPLOGINMESG;
756 
757 			/*
758 			 * Preparse the line so we can use its info
759 			 * for all the addresses associated with
760 			 * the virtual host name.
761 			 * Field 0, the virtual host name, is special:
762 			 * it's already parsed off and will be strdup'ed
763 			 * later, after we know its canonical form.
764 			 */
765 			for (i = 1; i < 5 && (cp = strtok(NULL, " \t")); i++)
766 				if (*cp != '-' && (cp = strdup(cp)))
767 					switch (i) {
768 					case 1:	/* anon user permissions */
769 						anonuser = cp;
770 						break;
771 					case 2: /* statistics file */
772 						statfile = cp;
773 						break;
774 					case 3: /* welcome message */
775 						welcome  = cp;
776 						break;
777 					case 4: /* login message */
778 						loginmsg = cp;
779 						break;
780 					default: /* programming error */
781 						abort();
782 						/* NOTREACHED */
783 					}
784 
785 			hints.ai_flags = AI_PASSIVE;
786 			hints.ai_family = family;
787 			hints.ai_socktype = SOCK_STREAM;
788 			if (getaddrinfo(vhost, NULL, &hints, &res) != 0)
789 				goto nextline;
790 			for (ai = res; ai != NULL && ai->ai_addr != NULL;
791 			     ai = ai->ai_next) {
792 
793 			gothost = 0;
794 			for (hrp = firsthost; hrp != NULL; hrp = hrp->next) {
795 				struct addrinfo *hi;
796 
797 				for (hi = hrp->hostinfo; hi != NULL;
798 				     hi = hi->ai_next)
799 					if (hi->ai_addrlen == ai->ai_addrlen &&
800 					    memcmp(hi->ai_addr,
801 						   ai->ai_addr,
802 						   ai->ai_addr->sa_len) == 0) {
803 						gothost++;
804 						break;
805 					}
806 				if (gothost)
807 					break;
808 			}
809 			if (hrp == NULL) {
810 				if ((hrp = malloc(sizeof(struct ftphost))) == NULL)
811 					goto nextline;
812 				hrp->hostname = NULL;
813 				insert = 1;
814 			} else {
815 				if (hrp->hostinfo && hrp->hostinfo != res)
816 					freeaddrinfo(hrp->hostinfo);
817 				insert = 0; /* host already in the chain */
818 			}
819 			hrp->hostinfo = res;
820 
821 			/*
822 			 * determine hostname to use.
823 			 * force defined name if there is a valid alias
824 			 * otherwise fallback to primary hostname
825 			 */
826 			/* XXX: getaddrinfo() can't do alias check */
827 			switch(hrp->hostinfo->ai_family) {
828 			case AF_INET:
829 				addr = &((struct sockaddr_in *)hrp->hostinfo->ai_addr)->sin_addr;
830 				addrsize = sizeof(struct in_addr);
831 				break;
832 			case AF_INET6:
833 				addr = &((struct sockaddr_in6 *)hrp->hostinfo->ai_addr)->sin6_addr;
834 				addrsize = sizeof(struct in6_addr);
835 				break;
836 			default:
837 				/* should not reach here */
838 				freeaddrinfo(hrp->hostinfo);
839 				if (insert)
840 					free(hrp); /*not in chain, can free*/
841 				else
842 					hrp->hostinfo = NULL; /*mark as blank*/
843 				goto nextline;
844 				/* NOTREACHED */
845 			}
846 			if ((hp = getipnodebyaddr(addr, addrsize,
847 						  hrp->hostinfo->ai_family,
848 						  &hp_error)) != NULL) {
849 				if (strcmp(vhost, hp->h_name) != 0) {
850 					if (hp->h_aliases == NULL)
851 						vhost = hp->h_name;
852 					else {
853 						i = 0;
854 						while (hp->h_aliases[i] &&
855 						       strcmp(vhost, hp->h_aliases[i]) != 0)
856 							++i;
857 						if (hp->h_aliases[i] == NULL)
858 							vhost = hp->h_name;
859 					}
860 				}
861 			}
862 			if (hrp->hostname &&
863 			    strcmp(hrp->hostname, vhost) != 0) {
864 				free(hrp->hostname);
865 				hrp->hostname = NULL;
866 			}
867 			if (hrp->hostname == NULL &&
868 			    (hrp->hostname = strdup(vhost)) == NULL) {
869 				freeaddrinfo(hrp->hostinfo);
870 				hrp->hostinfo = NULL; /* mark as blank */
871 				if (hp)
872 					freehostent(hp);
873 				goto nextline;
874 			}
875 			hrp->anonuser = anonuser;
876 			hrp->statfile = statfile;
877 			hrp->welcome  = welcome;
878 			hrp->loginmsg = loginmsg;
879 			if (insert) {
880 				hrp->next  = NULL;
881 				lhrp->next = hrp;
882 				lhrp = hrp;
883 			}
884 			if (hp)
885 				freehostent(hp);
886 		      }
887 nextline:
888 			if (mp)
889 				free(mp);
890 		}
891 		(void) fclose(fp);
892 	}
893 }
894 
895 static void
896 selecthost(union sockunion *su)
897 {
898 	struct ftphost	*hrp;
899 	u_int16_t port;
900 #ifdef INET6
901 	struct in6_addr *mapped_in6 = NULL;
902 #endif
903 	struct addrinfo *hi;
904 
905 #ifdef INET6
906 	/*
907 	 * XXX IPv4 mapped IPv6 addr consideraton,
908 	 * specified in rfc2373.
909 	 */
910 	if (su->su_family == AF_INET6 &&
911 	    IN6_IS_ADDR_V4MAPPED(&su->su_sin6.sin6_addr))
912 		mapped_in6 = &su->su_sin6.sin6_addr;
913 #endif
914 
915 	hrp = thishost = firsthost;	/* default */
916 	port = su->su_port;
917 	su->su_port = 0;
918 	while (hrp != NULL) {
919 	    for (hi = hrp->hostinfo; hi != NULL; hi = hi->ai_next) {
920 		if (memcmp(su, hi->ai_addr, hi->ai_addrlen) == 0) {
921 			thishost = hrp;
922 			goto found;
923 		}
924 #ifdef INET6
925 		/* XXX IPv4 mapped IPv6 addr consideraton */
926 		if (hi->ai_addr->sa_family == AF_INET && mapped_in6 != NULL &&
927 		    (memcmp(&mapped_in6->s6_addr[12],
928 			    &((struct sockaddr_in *)hi->ai_addr)->sin_addr,
929 			    sizeof(struct in_addr)) == 0)) {
930 			thishost = hrp;
931 			goto found;
932 		}
933 #endif
934 	    }
935 	    hrp = hrp->next;
936 	}
937 found:
938 	su->su_port = port;
939 	/* setup static variables as appropriate */
940 	hostname = thishost->hostname;
941 	ftpuser = thishost->anonuser;
942 }
943 #endif
944 
945 /*
946  * Helper function for sgetpwnam().
947  */
948 static char *
949 sgetsave(char *s)
950 {
951 	char *new = malloc(strlen(s) + 1);
952 
953 	if (new == NULL) {
954 		reply(421, "Ran out of memory.");
955 		dologout(1);
956 		/* NOTREACHED */
957 	}
958 	(void) strcpy(new, s);
959 	return (new);
960 }
961 
962 /*
963  * Save the result of a getpwnam.  Used for USER command, since
964  * the data returned must not be clobbered by any other command
965  * (e.g., globbing).
966  * NB: The data returned by sgetpwnam() will remain valid until
967  * the next call to this function.  Its difference from getpwnam()
968  * is that sgetpwnam() is known to be called from ftpd code only.
969  */
970 static struct passwd *
971 sgetpwnam(char *name)
972 {
973 	static struct passwd save;
974 	struct passwd *p;
975 
976 	if ((p = getpwnam(name)) == NULL)
977 		return (p);
978 	if (save.pw_name) {
979 		free(save.pw_name);
980 		free(save.pw_passwd);
981 		free(save.pw_class);
982 		free(save.pw_gecos);
983 		free(save.pw_dir);
984 		free(save.pw_shell);
985 	}
986 	save = *p;
987 	save.pw_name = sgetsave(p->pw_name);
988 	save.pw_passwd = sgetsave(p->pw_passwd);
989 	save.pw_class = sgetsave(p->pw_class);
990 	save.pw_gecos = sgetsave(p->pw_gecos);
991 	save.pw_dir = sgetsave(p->pw_dir);
992 	save.pw_shell = sgetsave(p->pw_shell);
993 	return (&save);
994 }
995 
996 static int login_attempts;	/* number of failed login attempts */
997 static int askpasswd;		/* had user command, ask for passwd */
998 static char curname[MAXLOGNAME];	/* current USER name */
999 
1000 /*
1001  * USER command.
1002  * Sets global passwd pointer pw if named account exists and is acceptable;
1003  * sets askpasswd if a PASS command is expected.  If logged in previously,
1004  * need to reset state.  If name is "ftp" or "anonymous", the name is not in
1005  * _PATH_FTPUSERS, and ftp account exists, set guest and pw, then just return.
1006  * If account doesn't exist, ask for passwd anyway.  Otherwise, check user
1007  * requesting login privileges.  Disallow anyone who does not have a standard
1008  * shell as returned by getusershell().  Disallow anyone mentioned in the file
1009  * _PATH_FTPUSERS to allow people such as root and uucp to be avoided.
1010  */
1011 void
1012 user(char *name)
1013 {
1014 	int ecode;
1015 	char *cp, *shell;
1016 
1017 	if (logged_in) {
1018 		if (guest) {
1019 			reply(530, "Can't change user from guest login.");
1020 			return;
1021 		} else if (dochroot) {
1022 			reply(530, "Can't change user from chroot user.");
1023 			return;
1024 		}
1025 		end_login();
1026 	}
1027 
1028 	guest = 0;
1029 #ifdef VIRTUAL_HOSTING
1030 	pw = sgetpwnam(thishost->anonuser);
1031 #else
1032 	pw = sgetpwnam("ftp");
1033 #endif
1034 	if (strcmp(name, "ftp") == 0 || strcmp(name, "anonymous") == 0) {
1035 		if (checkuser(_PATH_FTPUSERS, "ftp", 0, NULL, &ecode) ||
1036 		    (ecode != 0 && ecode != ENOENT))
1037 			reply(530, "User %s access denied.", name);
1038 		else if (checkuser(_PATH_FTPUSERS, "anonymous", 0, NULL, &ecode) ||
1039 		    (ecode != 0 && ecode != ENOENT))
1040 			reply(530, "User %s access denied.", name);
1041 		else if (pw != NULL) {
1042 			guest = 1;
1043 			askpasswd = 1;
1044 			reply(331,
1045 			"Guest login ok, send your email address as password.");
1046 		} else
1047 			reply(530, "User %s unknown.", name);
1048 		if (!askpasswd && logging)
1049 			syslog(LOG_NOTICE,
1050 			    "ANONYMOUS FTP LOGIN REFUSED FROM %s", remotehost);
1051 		return;
1052 	}
1053 	if (anon_only != 0) {
1054 		reply(530, "Sorry, only anonymous ftp allowed.");
1055 		return;
1056 	}
1057 
1058 	if ((pw = sgetpwnam(name))) {
1059 		if ((shell = pw->pw_shell) == NULL || *shell == 0)
1060 			shell = _PATH_BSHELL;
1061 		setusershell();
1062 		while ((cp = getusershell()) != NULL)
1063 			if (strcmp(cp, shell) == 0)
1064 				break;
1065 		endusershell();
1066 
1067 		if (cp == NULL ||
1068 		    (checkuser(_PATH_FTPUSERS, name, 1, NULL, &ecode) ||
1069 		    (ecode != 0 && ecode != ENOENT))) {
1070 			reply(530, "User %s access denied.", name);
1071 			if (logging)
1072 				syslog(LOG_NOTICE,
1073 				    "FTP LOGIN REFUSED FROM %s, %s",
1074 				    remotehost, name);
1075 			pw = NULL;
1076 			return;
1077 		}
1078 	}
1079 	if (logging)
1080 		strlcpy(curname, name, sizeof(curname));
1081 
1082 	pwok = 0;
1083 #ifdef USE_PAM
1084 	/* XXX Kluge! The conversation mechanism needs to be fixed. */
1085 #endif
1086 	if (opiechallenge(&opiedata, name, opieprompt) == 0) {
1087 		pwok = (pw != NULL) &&
1088 		       opieaccessfile(remotehost) &&
1089 		       opiealways(pw->pw_dir);
1090 		reply(331, "Response to %s %s for %s.",
1091 		      opieprompt, pwok ? "requested" : "required", name);
1092 	} else {
1093 		pwok = 1;
1094 		reply(331, "Password required for %s.", name);
1095 	}
1096 	askpasswd = 1;
1097 	/*
1098 	 * Delay before reading passwd after first failed
1099 	 * attempt to slow down passwd-guessing programs.
1100 	 */
1101 	if (login_attempts)
1102 		sleep(login_attempts);
1103 }
1104 
1105 /*
1106  * Check if a user is in the file "fname",
1107  * return a pointer to a malloc'd string with the rest
1108  * of the matching line in "residue" if not NULL.
1109  */
1110 static int
1111 checkuser(char *fname, char *name, int pwset, char **residue, int *ecode)
1112 {
1113 	FILE *fd;
1114 	int found = 0;
1115 	size_t len;
1116 	char *line, *mp, *p;
1117 
1118 	if (ecode != NULL)
1119 		*ecode = 0;
1120 	if ((fd = fopen(fname, "r")) != NULL) {
1121 		while (!found && (line = fgetln(fd, &len)) != NULL) {
1122 			/* skip comments */
1123 			if (line[0] == '#')
1124 				continue;
1125 			if (line[len - 1] == '\n') {
1126 				line[len - 1] = '\0';
1127 				mp = NULL;
1128 			} else {
1129 				if ((mp = malloc(len + 1)) == NULL)
1130 					fatalerror("Ran out of memory.");
1131 				memcpy(mp, line, len);
1132 				mp[len] = '\0';
1133 				line = mp;
1134 			}
1135 			/* avoid possible leading and trailing whitespace */
1136 			p = strtok(line, " \t");
1137 			/* skip empty lines */
1138 			if (p == NULL)
1139 				goto nextline;
1140 			/*
1141 			 * if first chr is '@', check group membership
1142 			 */
1143 			if (p[0] == '@') {
1144 				int i = 0;
1145 				struct group *grp;
1146 
1147 				if (p[1] == '\0') /* single @ matches anyone */
1148 					found = 1;
1149 				else {
1150 					if ((grp = getgrnam(p+1)) == NULL)
1151 						goto nextline;
1152 					/*
1153 					 * Check user's default group
1154 					 */
1155 					if (pwset && grp->gr_gid == pw->pw_gid)
1156 						found = 1;
1157 					/*
1158 					 * Check supplementary groups
1159 					 */
1160 					while (!found && grp->gr_mem[i])
1161 						found = strcmp(name,
1162 							grp->gr_mem[i++])
1163 							== 0;
1164 				}
1165 			}
1166 			/*
1167 			 * Otherwise, just check for username match
1168 			 */
1169 			else
1170 				found = strcmp(p, name) == 0;
1171 			/*
1172 			 * Save the rest of line to "residue" if matched
1173 			 */
1174 			if (found && residue) {
1175 				if ((p = strtok(NULL, "")) != NULL)
1176 					p += strspn(p, " \t");
1177 				if (p && *p) {
1178 				 	if ((*residue = strdup(p)) == NULL)
1179 						fatalerror("Ran out of memory.");
1180 				} else
1181 					*residue = NULL;
1182 			}
1183 nextline:
1184 			if (mp)
1185 				free(mp);
1186 		}
1187 		(void) fclose(fd);
1188 	} else if (ecode != NULL)
1189 		*ecode = errno;
1190 	return (found);
1191 }
1192 
1193 /*
1194  * Terminate login as previous user, if any, resetting state;
1195  * used when USER command is given or login fails.
1196  */
1197 static void
1198 end_login(void)
1199 {
1200 #ifdef USE_PAM
1201 	int e;
1202 #endif
1203 
1204 	(void) seteuid(0);
1205 #ifdef	LOGIN_CAP
1206 	setusercontext(NULL, getpwuid(0), 0, LOGIN_SETALL & ~(LOGIN_SETLOGIN |
1207 		       LOGIN_SETUSER | LOGIN_SETGROUP | LOGIN_SETPATH |
1208 		       LOGIN_SETENV));
1209 #endif
1210 	if (logged_in && dowtmp)
1211 		ftpd_logwtmp(wtmpid, NULL, NULL);
1212 	pw = NULL;
1213 #ifdef USE_PAM
1214 	if (pamh) {
1215 		if ((e = pam_setcred(pamh, PAM_DELETE_CRED)) != PAM_SUCCESS)
1216 			syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, e));
1217 		if ((e = pam_close_session(pamh,0)) != PAM_SUCCESS)
1218 			syslog(LOG_ERR, "pam_close_session: %s", pam_strerror(pamh, e));
1219 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS)
1220 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1221 		pamh = NULL;
1222 	}
1223 #endif
1224 	logged_in = 0;
1225 	guest = 0;
1226 	dochroot = 0;
1227 }
1228 
1229 #ifdef USE_PAM
1230 
1231 /*
1232  * the following code is stolen from imap-uw PAM authentication module and
1233  * login.c
1234  */
1235 #define COPY_STRING(s) (s ? strdup(s) : NULL)
1236 
1237 struct cred_t {
1238 	const char *uname;		/* user name */
1239 	const char *pass;		/* password */
1240 };
1241 typedef struct cred_t cred_t;
1242 
1243 static int
1244 auth_conv(int num_msg, const struct pam_message **msg,
1245 	  struct pam_response **resp, void *appdata)
1246 {
1247 	int i;
1248 	cred_t *cred = (cred_t *) appdata;
1249 	struct pam_response *reply;
1250 
1251 	reply = calloc(num_msg, sizeof *reply);
1252 	if (reply == NULL)
1253 		return PAM_BUF_ERR;
1254 
1255 	for (i = 0; i < num_msg; i++) {
1256 		switch (msg[i]->msg_style) {
1257 		case PAM_PROMPT_ECHO_ON:	/* assume want user name */
1258 			reply[i].resp_retcode = PAM_SUCCESS;
1259 			reply[i].resp = COPY_STRING(cred->uname);
1260 			/* PAM frees resp. */
1261 			break;
1262 		case PAM_PROMPT_ECHO_OFF:	/* assume want password */
1263 			reply[i].resp_retcode = PAM_SUCCESS;
1264 			reply[i].resp = COPY_STRING(cred->pass);
1265 			/* PAM frees resp. */
1266 			break;
1267 		case PAM_TEXT_INFO:
1268 		case PAM_ERROR_MSG:
1269 			reply[i].resp_retcode = PAM_SUCCESS;
1270 			reply[i].resp = NULL;
1271 			break;
1272 		default:			/* unknown message style */
1273 			free(reply);
1274 			return PAM_CONV_ERR;
1275 		}
1276 	}
1277 
1278 	*resp = reply;
1279 	return PAM_SUCCESS;
1280 }
1281 
1282 /*
1283  * Attempt to authenticate the user using PAM.  Returns 0 if the user is
1284  * authenticated, or 1 if not authenticated.  If some sort of PAM system
1285  * error occurs (e.g., the "/etc/pam.conf" file is missing) then this
1286  * function returns -1.  This can be used as an indication that we should
1287  * fall back to a different authentication mechanism.
1288  */
1289 static int
1290 auth_pam(struct passwd **ppw, const char *pass)
1291 {
1292 	const char *tmpl_user;
1293 	const void *item;
1294 	int rval;
1295 	int e;
1296 	cred_t auth_cred = { (*ppw)->pw_name, pass };
1297 	struct pam_conv conv = { &auth_conv, &auth_cred };
1298 
1299 	e = pam_start("ftpd", (*ppw)->pw_name, &conv, &pamh);
1300 	if (e != PAM_SUCCESS) {
1301 		/*
1302 		 * In OpenPAM, it's OK to pass NULL to pam_strerror()
1303 		 * if context creation has failed in the first place.
1304 		 */
1305 		syslog(LOG_ERR, "pam_start: %s", pam_strerror(NULL, e));
1306 		return -1;
1307 	}
1308 
1309 	e = pam_set_item(pamh, PAM_RHOST, remotehost);
1310 	if (e != PAM_SUCCESS) {
1311 		syslog(LOG_ERR, "pam_set_item(PAM_RHOST): %s",
1312 			pam_strerror(pamh, e));
1313 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
1314 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1315 		}
1316 		pamh = NULL;
1317 		return -1;
1318 	}
1319 
1320 	e = pam_authenticate(pamh, 0);
1321 	switch (e) {
1322 	case PAM_SUCCESS:
1323 		/*
1324 		 * With PAM we support the concept of a "template"
1325 		 * user.  The user enters a login name which is
1326 		 * authenticated by PAM, usually via a remote service
1327 		 * such as RADIUS or TACACS+.  If authentication
1328 		 * succeeds, a different but related "template" name
1329 		 * is used for setting the credentials, shell, and
1330 		 * home directory.  The name the user enters need only
1331 		 * exist on the remote authentication server, but the
1332 		 * template name must be present in the local password
1333 		 * database.
1334 		 *
1335 		 * This is supported by two various mechanisms in the
1336 		 * individual modules.  However, from the application's
1337 		 * point of view, the template user is always passed
1338 		 * back as a changed value of the PAM_USER item.
1339 		 */
1340 		if ((e = pam_get_item(pamh, PAM_USER, &item)) ==
1341 		    PAM_SUCCESS) {
1342 			tmpl_user = (const char *) item;
1343 			if (strcmp((*ppw)->pw_name, tmpl_user) != 0)
1344 				*ppw = getpwnam(tmpl_user);
1345 		} else
1346 			syslog(LOG_ERR, "Couldn't get PAM_USER: %s",
1347 			    pam_strerror(pamh, e));
1348 		rval = 0;
1349 		break;
1350 
1351 	case PAM_AUTH_ERR:
1352 	case PAM_USER_UNKNOWN:
1353 	case PAM_MAXTRIES:
1354 		rval = 1;
1355 		break;
1356 
1357 	default:
1358 		syslog(LOG_ERR, "pam_authenticate: %s", pam_strerror(pamh, e));
1359 		rval = -1;
1360 		break;
1361 	}
1362 
1363 	if (rval == 0) {
1364 		e = pam_acct_mgmt(pamh, 0);
1365 		if (e != PAM_SUCCESS) {
1366 			syslog(LOG_ERR, "pam_acct_mgmt: %s",
1367 						pam_strerror(pamh, e));
1368 			rval = 1;
1369 		}
1370 	}
1371 
1372 	if (rval != 0) {
1373 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
1374 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1375 		}
1376 		pamh = NULL;
1377 	}
1378 	return rval;
1379 }
1380 
1381 #endif /* USE_PAM */
1382 
1383 void
1384 pass(char *passwd)
1385 {
1386 	int rval, ecode;
1387 	FILE *fd;
1388 #ifdef	LOGIN_CAP
1389 	login_cap_t *lc = NULL;
1390 #endif
1391 #ifdef USE_PAM
1392 	int e;
1393 #endif
1394 	char *residue = NULL;
1395 	char *xpasswd;
1396 
1397 	if (logged_in || askpasswd == 0) {
1398 		reply(503, "Login with USER first.");
1399 		return;
1400 	}
1401 	askpasswd = 0;
1402 	if (!guest) {		/* "ftp" is only account allowed no password */
1403 		if (pw == NULL) {
1404 			rval = 1;	/* failure below */
1405 			goto skip;
1406 		}
1407 #ifdef USE_PAM
1408 		rval = auth_pam(&pw, passwd);
1409 		if (rval >= 0) {
1410 			opieunlock();
1411 			goto skip;
1412 		}
1413 #endif
1414 		if (opieverify(&opiedata, passwd) == 0)
1415 			xpasswd = pw->pw_passwd;
1416 		else if (pwok) {
1417 			xpasswd = crypt(passwd, pw->pw_passwd);
1418 			if (passwd[0] == '\0' && pw->pw_passwd[0] != '\0')
1419 				xpasswd = ":";
1420 		} else {
1421 			rval = 1;
1422 			goto skip;
1423 		}
1424 		rval = strcmp(pw->pw_passwd, xpasswd);
1425 		if (pw->pw_expire && time(NULL) >= pw->pw_expire)
1426 			rval = 1;	/* failure */
1427 skip:
1428 		/*
1429 		 * If rval == 1, the user failed the authentication check
1430 		 * above.  If rval == 0, either PAM or local authentication
1431 		 * succeeded.
1432 		 */
1433 		if (rval) {
1434 			reply(530, "Login incorrect.");
1435 			BLACKLIST_NOTIFY(BLACKLIST_AUTH_FAIL, STDIN_FILENO, "Login incorrect");
1436 			if (logging) {
1437 				syslog(LOG_NOTICE,
1438 				    "FTP LOGIN FAILED FROM %s",
1439 				    remotehost);
1440 				syslog(LOG_AUTHPRIV | LOG_NOTICE,
1441 				    "FTP LOGIN FAILED FROM %s, %s",
1442 				    remotehost, curname);
1443 			}
1444 			pw = NULL;
1445 			if (login_attempts++ >= 5) {
1446 				syslog(LOG_NOTICE,
1447 				    "repeated login failures from %s",
1448 				    remotehost);
1449 				exit(0);
1450 			}
1451 			return;
1452 		} else {
1453 			BLACKLIST_NOTIFY(BLACKLIST_AUTH_OK, STDIN_FILENO, "Login successful");
1454 		}
1455 	}
1456 	login_attempts = 0;		/* this time successful */
1457 	if (setegid(pw->pw_gid) < 0) {
1458 		reply(550, "Can't set gid.");
1459 		return;
1460 	}
1461 	/* May be overridden by login.conf */
1462 	(void) umask(defumask);
1463 #ifdef	LOGIN_CAP
1464 	if ((lc = login_getpwclass(pw)) != NULL) {
1465 		char	remote_ip[NI_MAXHOST];
1466 
1467 		if (getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
1468 			remote_ip, sizeof(remote_ip) - 1, NULL, 0,
1469 			NI_NUMERICHOST))
1470 				*remote_ip = 0;
1471 		remote_ip[sizeof(remote_ip) - 1] = 0;
1472 		if (!auth_hostok(lc, remotehost, remote_ip)) {
1473 			syslog(LOG_INFO|LOG_AUTH,
1474 			    "FTP LOGIN FAILED (HOST) as %s: permission denied.",
1475 			    pw->pw_name);
1476 			reply(530, "Permission denied.");
1477 			pw = NULL;
1478 			return;
1479 		}
1480 		if (!auth_timeok(lc, time(NULL))) {
1481 			reply(530, "Login not available right now.");
1482 			pw = NULL;
1483 			return;
1484 		}
1485 	}
1486 	setusercontext(lc, pw, 0, LOGIN_SETALL &
1487 		       ~(LOGIN_SETRESOURCES | LOGIN_SETUSER | LOGIN_SETPATH | LOGIN_SETENV));
1488 #else
1489 	setlogin(pw->pw_name);
1490 	(void) initgroups(pw->pw_name, pw->pw_gid);
1491 #endif
1492 
1493 #ifdef USE_PAM
1494 	if (pamh) {
1495 		if ((e = pam_open_session(pamh, 0)) != PAM_SUCCESS) {
1496 			syslog(LOG_ERR, "pam_open_session: %s", pam_strerror(pamh, e));
1497 		} else if ((e = pam_setcred(pamh, PAM_ESTABLISH_CRED)) != PAM_SUCCESS) {
1498 			syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, e));
1499 		}
1500 	}
1501 #endif
1502 
1503 	dochroot =
1504 		checkuser(_PATH_FTPCHROOT, pw->pw_name, 1, &residue, &ecode)
1505 #ifdef	LOGIN_CAP	/* Allow login.conf configuration as well */
1506 		|| login_getcapbool(lc, "ftp-chroot", 0)
1507 #endif
1508 	;
1509 	/*
1510 	 * It is possible that checkuser() failed to open the chroot file.
1511 	 * If this is the case, report that logins are un-available, since we
1512 	 * have no way of checking whether or not the user should be chrooted.
1513 	 * We ignore ENOENT since it is not required that this file be present.
1514 	 */
1515 	if (ecode != 0 && ecode != ENOENT) {
1516 		reply(530, "Login not available right now.");
1517 		return;
1518 	}
1519 	chrootdir = NULL;
1520 
1521 	/* Disable wtmp logging when chrooting. */
1522 	if (dochroot || guest)
1523 		dowtmp = 0;
1524 	if (dowtmp)
1525 		ftpd_logwtmp(wtmpid, pw->pw_name,
1526 		    (struct sockaddr *)&his_addr);
1527 	logged_in = 1;
1528 
1529 #ifdef	LOGIN_CAP
1530 	setusercontext(lc, pw, 0, LOGIN_SETRESOURCES);
1531 #endif
1532 
1533 	if (guest && stats && statfd < 0) {
1534 #ifdef VIRTUAL_HOSTING
1535 		statfd = open(thishost->statfile, O_WRONLY|O_APPEND);
1536 #else
1537 		statfd = open(_PATH_FTPDSTATFILE, O_WRONLY|O_APPEND);
1538 #endif
1539 		if (statfd < 0)
1540 			stats = 0;
1541 	}
1542 
1543 	/*
1544 	 * For a chrooted local user,
1545 	 * a) see whether ftpchroot(5) specifies a chroot directory,
1546 	 * b) extract the directory pathname from the line,
1547 	 * c) expand it to the absolute pathname if necessary.
1548 	 */
1549 	if (dochroot && residue &&
1550 	    (chrootdir = strtok(residue, " \t")) != NULL) {
1551 		if (chrootdir[0] != '/')
1552 			asprintf(&chrootdir, "%s/%s", pw->pw_dir, chrootdir);
1553 		else
1554 			chrootdir = strdup(chrootdir); /* make it permanent */
1555 		if (chrootdir == NULL)
1556 			fatalerror("Ran out of memory.");
1557 	}
1558 	if (guest || dochroot) {
1559 		/*
1560 		 * If no chroot directory set yet, use the login directory.
1561 		 * Copy it so it can be modified while pw->pw_dir stays intact.
1562 		 */
1563 		if (chrootdir == NULL &&
1564 		    (chrootdir = strdup(pw->pw_dir)) == NULL)
1565 			fatalerror("Ran out of memory.");
1566 		/*
1567 		 * Check for the "/chroot/./home" syntax,
1568 		 * separate the chroot and home directory pathnames.
1569 		 */
1570 		if ((homedir = strstr(chrootdir, "/./")) != NULL) {
1571 			*(homedir++) = '\0';	/* wipe '/' */
1572 			homedir++;		/* skip '.' */
1573 		} else {
1574 			/*
1575 			 * We MUST do a chdir() after the chroot. Otherwise
1576 			 * the old current directory will be accessible as "."
1577 			 * outside the new root!
1578 			 */
1579 			homedir = "/";
1580 		}
1581 		/*
1582 		 * Finally, do chroot()
1583 		 */
1584 		if (chroot(chrootdir) < 0) {
1585 			reply(550, "Can't change root.");
1586 			goto bad;
1587 		}
1588 		__FreeBSD_libc_enter_restricted_mode();
1589 	} else	/* real user w/o chroot */
1590 		homedir = pw->pw_dir;
1591 	/*
1592 	 * Set euid *before* doing chdir() so
1593 	 * a) the user won't be carried to a directory that he couldn't reach
1594 	 *    on his own due to no permission to upper path components,
1595 	 * b) NFS mounted homedirs w/restrictive permissions will be accessible
1596 	 *    (uid 0 has no root power over NFS if not mapped explicitly.)
1597 	 */
1598 	if (seteuid(pw->pw_uid) < 0) {
1599 		if (guest || dochroot) {
1600 			fatalerror("Can't set uid.");
1601 		} else {
1602 			reply(550, "Can't set uid.");
1603 			goto bad;
1604 		}
1605 	}
1606 	/*
1607 	 * Do not allow the session to live if we're chroot()'ed and chdir()
1608 	 * fails. Otherwise the chroot jail can be escaped.
1609 	 */
1610 	if (chdir(homedir) < 0) {
1611 		if (guest || dochroot) {
1612 			fatalerror("Can't change to base directory.");
1613 		} else {
1614 			if (chdir("/") < 0) {
1615 				reply(550, "Root is inaccessible.");
1616 				goto bad;
1617 			}
1618 			lreply(230, "No directory! Logging in with home=/.");
1619 		}
1620 	}
1621 
1622 	/*
1623 	 * Display a login message, if it exists.
1624 	 * N.B. reply(230,) must follow the message.
1625 	 */
1626 #ifdef VIRTUAL_HOSTING
1627 	fd = fopen(thishost->loginmsg, "r");
1628 #else
1629 	fd = fopen(_PATH_FTPLOGINMESG, "r");
1630 #endif
1631 	if (fd != NULL) {
1632 		char *cp, line[LINE_MAX];
1633 
1634 		while (fgets(line, sizeof(line), fd) != NULL) {
1635 			if ((cp = strchr(line, '\n')) != NULL)
1636 				*cp = '\0';
1637 			lreply(230, "%s", line);
1638 		}
1639 		(void) fflush(stdout);
1640 		(void) fclose(fd);
1641 	}
1642 	if (guest) {
1643 		if (ident != NULL)
1644 			free(ident);
1645 		ident = strdup(passwd);
1646 		if (ident == NULL)
1647 			fatalerror("Ran out of memory.");
1648 
1649 		reply(230, "Guest login ok, access restrictions apply.");
1650 #ifdef SETPROCTITLE
1651 #ifdef VIRTUAL_HOSTING
1652 		if (thishost != firsthost)
1653 			snprintf(proctitle, sizeof(proctitle),
1654 				 "%s: anonymous(%s)/%s", remotehost, hostname,
1655 				 passwd);
1656 		else
1657 #endif
1658 			snprintf(proctitle, sizeof(proctitle),
1659 				 "%s: anonymous/%s", remotehost, passwd);
1660 		setproctitle("%s", proctitle);
1661 #endif /* SETPROCTITLE */
1662 		if (logging)
1663 			syslog(LOG_INFO, "ANONYMOUS FTP LOGIN FROM %s, %s",
1664 			    remotehost, passwd);
1665 	} else {
1666 		if (dochroot)
1667 			reply(230, "User %s logged in, "
1668 				   "access restrictions apply.", pw->pw_name);
1669 		else
1670 			reply(230, "User %s logged in.", pw->pw_name);
1671 
1672 #ifdef SETPROCTITLE
1673 		snprintf(proctitle, sizeof(proctitle),
1674 			 "%s: user/%s", remotehost, pw->pw_name);
1675 		setproctitle("%s", proctitle);
1676 #endif /* SETPROCTITLE */
1677 		if (logging)
1678 			syslog(LOG_INFO, "FTP LOGIN FROM %s as %s",
1679 			    remotehost, pw->pw_name);
1680 	}
1681 	if (logging && (guest || dochroot))
1682 		syslog(LOG_INFO, "session root changed to %s", chrootdir);
1683 #ifdef	LOGIN_CAP
1684 	login_close(lc);
1685 #endif
1686 	if (residue)
1687 		free(residue);
1688 	return;
1689 bad:
1690 	/* Forget all about it... */
1691 #ifdef	LOGIN_CAP
1692 	login_close(lc);
1693 #endif
1694 	if (residue)
1695 		free(residue);
1696 	end_login();
1697 }
1698 
1699 void
1700 retrieve(char *cmd, char *name)
1701 {
1702 	FILE *fin, *dout;
1703 	struct stat st;
1704 	int (*closefunc)(FILE *);
1705 	time_t start;
1706 	char line[BUFSIZ];
1707 
1708 	if (cmd == 0) {
1709 		fin = fopen(name, "r"), closefunc = fclose;
1710 		st.st_size = 0;
1711 	} else {
1712 		(void) snprintf(line, sizeof(line), cmd, name);
1713 		name = line;
1714 		fin = ftpd_popen(line, "r"), closefunc = ftpd_pclose;
1715 		st.st_size = -1;
1716 		st.st_blksize = BUFSIZ;
1717 	}
1718 	if (fin == NULL) {
1719 		if (errno != 0) {
1720 			perror_reply(550, name);
1721 			if (cmd == 0) {
1722 				LOGCMD("get", name);
1723 			}
1724 		}
1725 		return;
1726 	}
1727 	byte_count = -1;
1728 	if (cmd == 0) {
1729 		if (fstat(fileno(fin), &st) < 0) {
1730 			perror_reply(550, name);
1731 			goto done;
1732 		}
1733 		if (!S_ISREG(st.st_mode)) {
1734 			/*
1735 			 * Never sending a raw directory is a workaround
1736 			 * for buggy clients that will attempt to RETR
1737 			 * a directory before listing it, e.g., Mozilla.
1738 			 * Preventing a guest from getting irregular files
1739 			 * is a simple security measure.
1740 			 */
1741 			if (S_ISDIR(st.st_mode) || guest) {
1742 				reply(550, "%s: not a plain file.", name);
1743 				goto done;
1744 			}
1745 			st.st_size = -1;
1746 			/* st.st_blksize is set for all descriptor types */
1747 		}
1748 	}
1749 	if (restart_point) {
1750 		if (type == TYPE_A) {
1751 			off_t i, n;
1752 			int c;
1753 
1754 			n = restart_point;
1755 			i = 0;
1756 			while (i++ < n) {
1757 				if ((c=getc(fin)) == EOF) {
1758 					perror_reply(550, name);
1759 					goto done;
1760 				}
1761 				if (c == '\n')
1762 					i++;
1763 			}
1764 		} else if (lseek(fileno(fin), restart_point, L_SET) < 0) {
1765 			perror_reply(550, name);
1766 			goto done;
1767 		}
1768 	}
1769 	dout = dataconn(name, st.st_size, "w");
1770 	if (dout == NULL)
1771 		goto done;
1772 	time(&start);
1773 	send_data(fin, dout, st.st_blksize, st.st_size,
1774 		  restart_point == 0 && cmd == 0 && S_ISREG(st.st_mode));
1775 	if (cmd == 0 && guest && stats && byte_count > 0)
1776 		logxfer(name, byte_count, start);
1777 	(void) fclose(dout);
1778 	data = -1;
1779 	pdata = -1;
1780 done:
1781 	if (cmd == 0)
1782 		LOGBYTES("get", name, byte_count);
1783 	(*closefunc)(fin);
1784 }
1785 
1786 void
1787 store(char *name, char *mode, int unique)
1788 {
1789 	int fd;
1790 	FILE *fout, *din;
1791 	int (*closefunc)(FILE *);
1792 
1793 	if (*mode == 'a') {		/* APPE */
1794 		if (unique) {
1795 			/* Programming error */
1796 			syslog(LOG_ERR, "Internal: unique flag to APPE");
1797 			unique = 0;
1798 		}
1799 		if (guest && noguestmod) {
1800 			reply(550, "Appending to existing file denied.");
1801 			goto err;
1802 		}
1803 		restart_point = 0;	/* not affected by preceding REST */
1804 	}
1805 	if (unique)			/* STOU overrides REST */
1806 		restart_point = 0;
1807 	if (guest && noguestmod) {
1808 		if (restart_point) {	/* guest STOR w/REST */
1809 			reply(550, "Modifying existing file denied.");
1810 			goto err;
1811 		} else			/* treat guest STOR as STOU */
1812 			unique = 1;
1813 	}
1814 
1815 	if (restart_point)
1816 		mode = "r+";	/* so ASCII manual seek can work */
1817 	if (unique) {
1818 		if ((fd = guniquefd(name, &name)) < 0)
1819 			goto err;
1820 		fout = fdopen(fd, mode);
1821 	} else
1822 		fout = fopen(name, mode);
1823 	closefunc = fclose;
1824 	if (fout == NULL) {
1825 		perror_reply(553, name);
1826 		goto err;
1827 	}
1828 	byte_count = -1;
1829 	if (restart_point) {
1830 		if (type == TYPE_A) {
1831 			off_t i, n;
1832 			int c;
1833 
1834 			n = restart_point;
1835 			i = 0;
1836 			while (i++ < n) {
1837 				if ((c=getc(fout)) == EOF) {
1838 					perror_reply(550, name);
1839 					goto done;
1840 				}
1841 				if (c == '\n')
1842 					i++;
1843 			}
1844 			/*
1845 			 * We must do this seek to "current" position
1846 			 * because we are changing from reading to
1847 			 * writing.
1848 			 */
1849 			if (fseeko(fout, 0, SEEK_CUR) < 0) {
1850 				perror_reply(550, name);
1851 				goto done;
1852 			}
1853 		} else if (lseek(fileno(fout), restart_point, L_SET) < 0) {
1854 			perror_reply(550, name);
1855 			goto done;
1856 		}
1857 	}
1858 	din = dataconn(name, -1, "r");
1859 	if (din == NULL)
1860 		goto done;
1861 	if (receive_data(din, fout) == 0) {
1862 		if (unique)
1863 			reply(226, "Transfer complete (unique file name:%s).",
1864 			    name);
1865 		else
1866 			reply(226, "Transfer complete.");
1867 	}
1868 	(void) fclose(din);
1869 	data = -1;
1870 	pdata = -1;
1871 done:
1872 	LOGBYTES(*mode == 'a' ? "append" : "put", name, byte_count);
1873 	(*closefunc)(fout);
1874 	return;
1875 err:
1876 	LOGCMD(*mode == 'a' ? "append" : "put" , name);
1877 	return;
1878 }
1879 
1880 static FILE *
1881 getdatasock(char *mode)
1882 {
1883 	int on = 1, s, t, tries;
1884 
1885 	if (data >= 0)
1886 		return (fdopen(data, mode));
1887 
1888 	s = socket(data_dest.su_family, SOCK_STREAM, 0);
1889 	if (s < 0)
1890 		goto bad;
1891 	if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
1892 		syslog(LOG_WARNING, "data setsockopt (SO_REUSEADDR): %m");
1893 	/* anchor socket to avoid multi-homing problems */
1894 	data_source = ctrl_addr;
1895 	data_source.su_port = htons(dataport);
1896 	(void) seteuid(0);
1897 	for (tries = 1; ; tries++) {
1898 		/*
1899 		 * We should loop here since it's possible that
1900 		 * another ftpd instance has passed this point and is
1901 		 * trying to open a data connection in active mode now.
1902 		 * Until the other connection is opened, we'll be getting
1903 		 * EADDRINUSE because no SOCK_STREAM sockets in the system
1904 		 * can share both local and remote addresses, localIP:20
1905 		 * and *:* in this case.
1906 		 */
1907 		if (bind(s, (struct sockaddr *)&data_source,
1908 		    data_source.su_len) >= 0)
1909 			break;
1910 		if (errno != EADDRINUSE || tries > 10)
1911 			goto bad;
1912 		sleep(tries);
1913 	}
1914 	(void) seteuid(pw->pw_uid);
1915 #ifdef IP_TOS
1916 	if (data_source.su_family == AF_INET)
1917       {
1918 	on = IPTOS_THROUGHPUT;
1919 	if (setsockopt(s, IPPROTO_IP, IP_TOS, &on, sizeof(int)) < 0)
1920 		syslog(LOG_WARNING, "data setsockopt (IP_TOS): %m");
1921       }
1922 #endif
1923 #ifdef TCP_NOPUSH
1924 	/*
1925 	 * Turn off push flag to keep sender TCP from sending short packets
1926 	 * at the boundaries of each write().
1927 	 */
1928 	on = 1;
1929 	if (setsockopt(s, IPPROTO_TCP, TCP_NOPUSH, &on, sizeof on) < 0)
1930 		syslog(LOG_WARNING, "data setsockopt (TCP_NOPUSH): %m");
1931 #endif
1932 	return (fdopen(s, mode));
1933 bad:
1934 	/* Return the real value of errno (close may change it) */
1935 	t = errno;
1936 	(void) seteuid(pw->pw_uid);
1937 	(void) close(s);
1938 	errno = t;
1939 	return (NULL);
1940 }
1941 
1942 static FILE *
1943 dataconn(char *name, off_t size, char *mode)
1944 {
1945 	char sizebuf[32];
1946 	FILE *file;
1947 	int retry = 0, tos, conerrno;
1948 
1949 	file_size = size;
1950 	byte_count = 0;
1951 	if (size != -1)
1952 		(void) snprintf(sizebuf, sizeof(sizebuf),
1953 				" (%jd bytes)", (intmax_t)size);
1954 	else
1955 		*sizebuf = '\0';
1956 	if (pdata >= 0) {
1957 		union sockunion from;
1958 		socklen_t fromlen = ctrl_addr.su_len;
1959 		int flags, s;
1960 		struct timeval timeout;
1961 		fd_set set;
1962 
1963 		FD_ZERO(&set);
1964 		FD_SET(pdata, &set);
1965 
1966 		timeout.tv_usec = 0;
1967 		timeout.tv_sec = 120;
1968 
1969 		/*
1970 		 * Granted a socket is in the blocking I/O mode,
1971 		 * accept() will block after a successful select()
1972 		 * if the selected connection dies in between.
1973 		 * Therefore set the non-blocking I/O flag here.
1974 		 */
1975 		if ((flags = fcntl(pdata, F_GETFL, 0)) == -1 ||
1976 		    fcntl(pdata, F_SETFL, flags | O_NONBLOCK) == -1)
1977 			goto pdata_err;
1978 		if (select(pdata+1, &set, NULL, NULL, &timeout) <= 0 ||
1979 		    (s = accept(pdata, (struct sockaddr *) &from, &fromlen)) < 0)
1980 			goto pdata_err;
1981 		(void) close(pdata);
1982 		pdata = s;
1983 		/*
1984 		 * Unset the inherited non-blocking I/O flag
1985 		 * on the child socket so stdio can work on it.
1986 		 */
1987 		if ((flags = fcntl(pdata, F_GETFL, 0)) == -1 ||
1988 		    fcntl(pdata, F_SETFL, flags & ~O_NONBLOCK) == -1)
1989 			goto pdata_err;
1990 #ifdef IP_TOS
1991 		if (from.su_family == AF_INET)
1992 	      {
1993 		tos = IPTOS_THROUGHPUT;
1994 		if (setsockopt(s, IPPROTO_IP, IP_TOS, &tos, sizeof(int)) < 0)
1995 			syslog(LOG_WARNING, "pdata setsockopt (IP_TOS): %m");
1996 	      }
1997 #endif
1998 		reply(150, "Opening %s mode data connection for '%s'%s.",
1999 		     type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
2000 		return (fdopen(pdata, mode));
2001 pdata_err:
2002 		reply(425, "Can't open data connection.");
2003 		(void) close(pdata);
2004 		pdata = -1;
2005 		return (NULL);
2006 	}
2007 	if (data >= 0) {
2008 		reply(125, "Using existing data connection for '%s'%s.",
2009 		    name, sizebuf);
2010 		usedefault = 1;
2011 		return (fdopen(data, mode));
2012 	}
2013 	if (usedefault)
2014 		data_dest = his_addr;
2015 	usedefault = 1;
2016 	do {
2017 		file = getdatasock(mode);
2018 		if (file == NULL) {
2019 			char hostbuf[NI_MAXHOST], portbuf[NI_MAXSERV];
2020 
2021 			if (getnameinfo((struct sockaddr *)&data_source,
2022 				data_source.su_len,
2023 				hostbuf, sizeof(hostbuf) - 1,
2024 				portbuf, sizeof(portbuf) - 1,
2025 				NI_NUMERICHOST|NI_NUMERICSERV))
2026 					*hostbuf = *portbuf = 0;
2027 			hostbuf[sizeof(hostbuf) - 1] = 0;
2028 			portbuf[sizeof(portbuf) - 1] = 0;
2029 			reply(425, "Can't create data socket (%s,%s): %s.",
2030 				hostbuf, portbuf, strerror(errno));
2031 			return (NULL);
2032 		}
2033 		data = fileno(file);
2034 		conerrno = 0;
2035 		if (connect(data, (struct sockaddr *)&data_dest,
2036 		    data_dest.su_len) == 0)
2037 			break;
2038 		conerrno = errno;
2039 		(void) fclose(file);
2040 		data = -1;
2041 		if (conerrno == EADDRINUSE) {
2042 			sleep(swaitint);
2043 			retry += swaitint;
2044 		} else {
2045 			break;
2046 		}
2047 	} while (retry <= swaitmax);
2048 	if (conerrno != 0) {
2049 		reply(425, "Can't build data connection: %s.",
2050 			   strerror(conerrno));
2051 		return (NULL);
2052 	}
2053 	reply(150, "Opening %s mode data connection for '%s'%s.",
2054 	     type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
2055 	return (file);
2056 }
2057 
2058 /*
2059  * A helper macro to avoid code duplication
2060  * in send_data() and receive_data().
2061  *
2062  * XXX We have to block SIGURG during putc() because BSD stdio
2063  * is unable to restart interrupted write operations and hence
2064  * the entire buffer contents will be lost as soon as a write()
2065  * call indicates EINTR to stdio.
2066  */
2067 #define FTPD_PUTC(ch, file, label)					\
2068 	do {								\
2069 		int ret;						\
2070 									\
2071 		do {							\
2072 			START_UNSAFE;					\
2073 			ret = putc((ch), (file));			\
2074 			END_UNSAFE;					\
2075 			CHECKOOB(return (-1))				\
2076 			else if (ferror(file))				\
2077 				goto label;				\
2078 			clearerr(file);					\
2079 		} while (ret == EOF);					\
2080 	} while (0)
2081 
2082 /*
2083  * Transfer the contents of "instr" to "outstr" peer using the appropriate
2084  * encapsulation of the data subject to Mode, Structure, and Type.
2085  *
2086  * NB: Form isn't handled.
2087  */
2088 static int
2089 send_data(FILE *instr, FILE *outstr, size_t blksize, off_t filesize, int isreg)
2090 {
2091 	int c, cp, filefd, netfd;
2092 	char *buf;
2093 
2094 	STARTXFER;
2095 
2096 	switch (type) {
2097 
2098 	case TYPE_A:
2099 		cp = EOF;
2100 		for (;;) {
2101 			c = getc(instr);
2102 			CHECKOOB(return (-1))
2103 			else if (c == EOF && ferror(instr))
2104 				goto file_err;
2105 			if (c == EOF) {
2106 				if (ferror(instr)) {	/* resume after OOB */
2107 					clearerr(instr);
2108 					continue;
2109 				}
2110 				if (feof(instr))	/* EOF */
2111 					break;
2112 				syslog(LOG_ERR, "Internal: impossible condition"
2113 						" on file after getc()");
2114 				goto file_err;
2115 			}
2116 			if (c == '\n' && cp != '\r') {
2117 				FTPD_PUTC('\r', outstr, data_err);
2118 				byte_count++;
2119 			}
2120 			FTPD_PUTC(c, outstr, data_err);
2121 			byte_count++;
2122 			cp = c;
2123 		}
2124 #ifdef notyet	/* BSD stdio isn't ready for that */
2125 		while (fflush(outstr) == EOF) {
2126 			CHECKOOB(return (-1))
2127 			else
2128 				goto data_err;
2129 			clearerr(outstr);
2130 		}
2131 		ENDXFER;
2132 #else
2133 		ENDXFER;
2134 		if (fflush(outstr) == EOF)
2135 			goto data_err;
2136 #endif
2137 		reply(226, "Transfer complete.");
2138 		return (0);
2139 
2140 	case TYPE_I:
2141 	case TYPE_L:
2142 		/*
2143 		 * isreg is only set if we are not doing restart and we
2144 		 * are sending a regular file
2145 		 */
2146 		netfd = fileno(outstr);
2147 		filefd = fileno(instr);
2148 
2149 		if (isreg) {
2150 			char *msg = "Transfer complete.";
2151 			off_t cnt, offset;
2152 			int err;
2153 
2154 			cnt = offset = 0;
2155 
2156 			while (filesize > 0) {
2157 				err = sendfile(filefd, netfd, offset, 0,
2158 					       NULL, &cnt, 0);
2159 				/*
2160 				 * Calculate byte_count before OOB processing.
2161 				 * It can be used in myoob() later.
2162 				 */
2163 				byte_count += cnt;
2164 				offset += cnt;
2165 				filesize -= cnt;
2166 				CHECKOOB(return (-1))
2167 				else if (err == -1) {
2168 					if (errno != EINTR &&
2169 					    cnt == 0 && offset == 0)
2170 						goto oldway;
2171 					goto data_err;
2172 				}
2173 				if (err == -1)	/* resume after OOB */
2174 					continue;
2175 				/*
2176 				 * We hit the EOF prematurely.
2177 				 * Perhaps the file was externally truncated.
2178 				 */
2179 				if (cnt == 0) {
2180 					msg = "Transfer finished due to "
2181 					      "premature end of file.";
2182 					break;
2183 				}
2184 			}
2185 			ENDXFER;
2186 			reply(226, "%s", msg);
2187 			return (0);
2188 		}
2189 
2190 oldway:
2191 		if ((buf = malloc(blksize)) == NULL) {
2192 			ENDXFER;
2193 			reply(451, "Ran out of memory.");
2194 			return (-1);
2195 		}
2196 
2197 		for (;;) {
2198 			int cnt, len;
2199 			char *bp;
2200 
2201 			cnt = read(filefd, buf, blksize);
2202 			CHECKOOB(free(buf); return (-1))
2203 			else if (cnt < 0) {
2204 				free(buf);
2205 				goto file_err;
2206 			}
2207 			if (cnt < 0)	/* resume after OOB */
2208 				continue;
2209 			if (cnt == 0)	/* EOF */
2210 				break;
2211 			for (len = cnt, bp = buf; len > 0;) {
2212 				cnt = write(netfd, bp, len);
2213 				CHECKOOB(free(buf); return (-1))
2214 				else if (cnt < 0) {
2215 					free(buf);
2216 					goto data_err;
2217 				}
2218 				if (cnt <= 0)
2219 					continue;
2220 				len -= cnt;
2221 				bp += cnt;
2222 				byte_count += cnt;
2223 			}
2224 		}
2225 		ENDXFER;
2226 		free(buf);
2227 		reply(226, "Transfer complete.");
2228 		return (0);
2229 	default:
2230 		ENDXFER;
2231 		reply(550, "Unimplemented TYPE %d in send_data.", type);
2232 		return (-1);
2233 	}
2234 
2235 data_err:
2236 	ENDXFER;
2237 	perror_reply(426, "Data connection");
2238 	return (-1);
2239 
2240 file_err:
2241 	ENDXFER;
2242 	perror_reply(551, "Error on input file");
2243 	return (-1);
2244 }
2245 
2246 /*
2247  * Transfer data from peer to "outstr" using the appropriate encapulation of
2248  * the data subject to Mode, Structure, and Type.
2249  *
2250  * N.B.: Form isn't handled.
2251  */
2252 static int
2253 receive_data(FILE *instr, FILE *outstr)
2254 {
2255 	int c, cp;
2256 	int bare_lfs = 0;
2257 
2258 	STARTXFER;
2259 
2260 	switch (type) {
2261 
2262 	case TYPE_I:
2263 	case TYPE_L:
2264 		for (;;) {
2265 			int cnt, len;
2266 			char *bp;
2267 			char buf[BUFSIZ];
2268 
2269 			cnt = read(fileno(instr), buf, sizeof(buf));
2270 			CHECKOOB(return (-1))
2271 			else if (cnt < 0)
2272 				goto data_err;
2273 			if (cnt < 0)	/* resume after OOB */
2274 				continue;
2275 			if (cnt == 0)	/* EOF */
2276 				break;
2277 			for (len = cnt, bp = buf; len > 0;) {
2278 				cnt = write(fileno(outstr), bp, len);
2279 				CHECKOOB(return (-1))
2280 				else if (cnt < 0)
2281 					goto file_err;
2282 				if (cnt <= 0)
2283 					continue;
2284 				len -= cnt;
2285 				bp += cnt;
2286 				byte_count += cnt;
2287 			}
2288 		}
2289 		ENDXFER;
2290 		return (0);
2291 
2292 	case TYPE_E:
2293 		ENDXFER;
2294 		reply(553, "TYPE E not implemented.");
2295 		return (-1);
2296 
2297 	case TYPE_A:
2298 		cp = EOF;
2299 		for (;;) {
2300 			c = getc(instr);
2301 			CHECKOOB(return (-1))
2302 			else if (c == EOF && ferror(instr))
2303 				goto data_err;
2304 			if (c == EOF && ferror(instr)) { /* resume after OOB */
2305 				clearerr(instr);
2306 				continue;
2307 			}
2308 
2309 			if (cp == '\r') {
2310 				if (c != '\n')
2311 					FTPD_PUTC('\r', outstr, file_err);
2312 			} else
2313 				if (c == '\n')
2314 					bare_lfs++;
2315 			if (c == '\r') {
2316 				byte_count++;
2317 				cp = c;
2318 				continue;
2319 			}
2320 
2321 			/* Check for EOF here in order not to lose last \r. */
2322 			if (c == EOF) {
2323 				if (feof(instr))	/* EOF */
2324 					break;
2325 				syslog(LOG_ERR, "Internal: impossible condition"
2326 						" on data stream after getc()");
2327 				goto data_err;
2328 			}
2329 
2330 			byte_count++;
2331 			FTPD_PUTC(c, outstr, file_err);
2332 			cp = c;
2333 		}
2334 #ifdef notyet	/* BSD stdio isn't ready for that */
2335 		while (fflush(outstr) == EOF) {
2336 			CHECKOOB(return (-1))
2337 			else
2338 				goto file_err;
2339 			clearerr(outstr);
2340 		}
2341 		ENDXFER;
2342 #else
2343 		ENDXFER;
2344 		if (fflush(outstr) == EOF)
2345 			goto file_err;
2346 #endif
2347 		if (bare_lfs) {
2348 			lreply(226,
2349 		"WARNING! %d bare linefeeds received in ASCII mode.",
2350 			    bare_lfs);
2351 		(void)printf("   File may not have transferred correctly.\r\n");
2352 		}
2353 		return (0);
2354 	default:
2355 		ENDXFER;
2356 		reply(550, "Unimplemented TYPE %d in receive_data.", type);
2357 		return (-1);
2358 	}
2359 
2360 data_err:
2361 	ENDXFER;
2362 	perror_reply(426, "Data connection");
2363 	return (-1);
2364 
2365 file_err:
2366 	ENDXFER;
2367 	perror_reply(452, "Error writing to file");
2368 	return (-1);
2369 }
2370 
2371 void
2372 statfilecmd(char *filename)
2373 {
2374 	FILE *fin;
2375 	int atstart;
2376 	int c, code;
2377 	char line[LINE_MAX];
2378 	struct stat st;
2379 
2380 	code = lstat(filename, &st) == 0 && S_ISDIR(st.st_mode) ? 212 : 213;
2381 	(void)snprintf(line, sizeof(line), _PATH_LS " -lgA %s", filename);
2382 	fin = ftpd_popen(line, "r");
2383 	if (fin == NULL) {
2384 		perror_reply(551, filename);
2385 		return;
2386 	}
2387 	lreply(code, "Status of %s:", filename);
2388 	atstart = 1;
2389 	while ((c = getc(fin)) != EOF) {
2390 		if (c == '\n') {
2391 			if (ferror(stdout)){
2392 				perror_reply(421, "Control connection");
2393 				(void) ftpd_pclose(fin);
2394 				dologout(1);
2395 				/* NOTREACHED */
2396 			}
2397 			if (ferror(fin)) {
2398 				perror_reply(551, filename);
2399 				(void) ftpd_pclose(fin);
2400 				return;
2401 			}
2402 			(void) putc('\r', stdout);
2403 		}
2404 		/*
2405 		 * RFC 959 says neutral text should be prepended before
2406 		 * a leading 3-digit number followed by whitespace, but
2407 		 * many ftp clients can be confused by any leading digits,
2408 		 * as a matter of fact.
2409 		 */
2410 		if (atstart && isdigit(c))
2411 			(void) putc(' ', stdout);
2412 		(void) putc(c, stdout);
2413 		atstart = (c == '\n');
2414 	}
2415 	(void) ftpd_pclose(fin);
2416 	reply(code, "End of status.");
2417 }
2418 
2419 void
2420 statcmd(void)
2421 {
2422 	union sockunion *su;
2423 	u_char *a, *p;
2424 	char hname[NI_MAXHOST];
2425 	int ispassive;
2426 
2427 	if (hostinfo) {
2428 		lreply(211, "%s FTP server status:", hostname);
2429 		printf("     %s\r\n", version);
2430 	} else
2431 		lreply(211, "FTP server status:");
2432 	printf("     Connected to %s", remotehost);
2433 	if (!getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
2434 			 hname, sizeof(hname) - 1, NULL, 0, NI_NUMERICHOST)) {
2435 		hname[sizeof(hname) - 1] = 0;
2436 		if (strcmp(hname, remotehost) != 0)
2437 			printf(" (%s)", hname);
2438 	}
2439 	printf("\r\n");
2440 	if (logged_in) {
2441 		if (guest)
2442 			printf("     Logged in anonymously\r\n");
2443 		else
2444 			printf("     Logged in as %s\r\n", pw->pw_name);
2445 	} else if (askpasswd)
2446 		printf("     Waiting for password\r\n");
2447 	else
2448 		printf("     Waiting for user name\r\n");
2449 	printf("     TYPE: %s", typenames[type]);
2450 	if (type == TYPE_A || type == TYPE_E)
2451 		printf(", FORM: %s", formnames[form]);
2452 	if (type == TYPE_L)
2453 #if CHAR_BIT == 8
2454 		printf(" %d", CHAR_BIT);
2455 #else
2456 		printf(" %d", bytesize);	/* need definition! */
2457 #endif
2458 	printf("; STRUcture: %s; transfer MODE: %s\r\n",
2459 	    strunames[stru], modenames[mode]);
2460 	if (data != -1)
2461 		printf("     Data connection open\r\n");
2462 	else if (pdata != -1) {
2463 		ispassive = 1;
2464 		su = &pasv_addr;
2465 		goto printaddr;
2466 	} else if (usedefault == 0) {
2467 		ispassive = 0;
2468 		su = &data_dest;
2469 printaddr:
2470 #define UC(b) (((int) b) & 0xff)
2471 		if (epsvall) {
2472 			printf("     EPSV only mode (EPSV ALL)\r\n");
2473 			goto epsvonly;
2474 		}
2475 
2476 		/* PORT/PASV */
2477 		if (su->su_family == AF_INET) {
2478 			a = (u_char *) &su->su_sin.sin_addr;
2479 			p = (u_char *) &su->su_sin.sin_port;
2480 			printf("     %s (%d,%d,%d,%d,%d,%d)\r\n",
2481 				ispassive ? "PASV" : "PORT",
2482 				UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
2483 				UC(p[0]), UC(p[1]));
2484 		}
2485 
2486 		/* LPRT/LPSV */
2487 	    {
2488 		int alen, af, i;
2489 
2490 		switch (su->su_family) {
2491 		case AF_INET:
2492 			a = (u_char *) &su->su_sin.sin_addr;
2493 			p = (u_char *) &su->su_sin.sin_port;
2494 			alen = sizeof(su->su_sin.sin_addr);
2495 			af = 4;
2496 			break;
2497 		case AF_INET6:
2498 			a = (u_char *) &su->su_sin6.sin6_addr;
2499 			p = (u_char *) &su->su_sin6.sin6_port;
2500 			alen = sizeof(su->su_sin6.sin6_addr);
2501 			af = 6;
2502 			break;
2503 		default:
2504 			af = 0;
2505 			break;
2506 		}
2507 		if (af) {
2508 			printf("     %s (%d,%d,", ispassive ? "LPSV" : "LPRT",
2509 				af, alen);
2510 			for (i = 0; i < alen; i++)
2511 				printf("%d,", UC(a[i]));
2512 			printf("%d,%d,%d)\r\n", 2, UC(p[0]), UC(p[1]));
2513 		}
2514 	    }
2515 
2516 epsvonly:;
2517 		/* EPRT/EPSV */
2518 	    {
2519 		int af;
2520 
2521 		switch (su->su_family) {
2522 		case AF_INET:
2523 			af = 1;
2524 			break;
2525 		case AF_INET6:
2526 			af = 2;
2527 			break;
2528 		default:
2529 			af = 0;
2530 			break;
2531 		}
2532 		if (af) {
2533 			union sockunion tmp;
2534 
2535 			tmp = *su;
2536 			if (tmp.su_family == AF_INET6)
2537 				tmp.su_sin6.sin6_scope_id = 0;
2538 			if (!getnameinfo((struct sockaddr *)&tmp, tmp.su_len,
2539 					hname, sizeof(hname) - 1, NULL, 0,
2540 					NI_NUMERICHOST)) {
2541 				hname[sizeof(hname) - 1] = 0;
2542 				printf("     %s |%d|%s|%d|\r\n",
2543 					ispassive ? "EPSV" : "EPRT",
2544 					af, hname, htons(tmp.su_port));
2545 			}
2546 		}
2547 	    }
2548 #undef UC
2549 	} else
2550 		printf("     No data connection\r\n");
2551 	reply(211, "End of status.");
2552 }
2553 
2554 void
2555 fatalerror(char *s)
2556 {
2557 
2558 	reply(451, "Error in server: %s", s);
2559 	reply(221, "Closing connection due to server error.");
2560 	dologout(0);
2561 	/* NOTREACHED */
2562 }
2563 
2564 void
2565 reply(int n, const char *fmt, ...)
2566 {
2567 	va_list ap;
2568 
2569 	(void)printf("%d ", n);
2570 	va_start(ap, fmt);
2571 	(void)vprintf(fmt, ap);
2572 	va_end(ap);
2573 	(void)printf("\r\n");
2574 	(void)fflush(stdout);
2575 	if (ftpdebug) {
2576 		syslog(LOG_DEBUG, "<--- %d ", n);
2577 		va_start(ap, fmt);
2578 		vsyslog(LOG_DEBUG, fmt, ap);
2579 		va_end(ap);
2580 	}
2581 }
2582 
2583 void
2584 lreply(int n, const char *fmt, ...)
2585 {
2586 	va_list ap;
2587 
2588 	(void)printf("%d- ", n);
2589 	va_start(ap, fmt);
2590 	(void)vprintf(fmt, ap);
2591 	va_end(ap);
2592 	(void)printf("\r\n");
2593 	(void)fflush(stdout);
2594 	if (ftpdebug) {
2595 		syslog(LOG_DEBUG, "<--- %d- ", n);
2596 		va_start(ap, fmt);
2597 		vsyslog(LOG_DEBUG, fmt, ap);
2598 		va_end(ap);
2599 	}
2600 }
2601 
2602 static void
2603 ack(char *s)
2604 {
2605 
2606 	reply(250, "%s command successful.", s);
2607 }
2608 
2609 void
2610 nack(char *s)
2611 {
2612 
2613 	reply(502, "%s command not implemented.", s);
2614 }
2615 
2616 /* ARGSUSED */
2617 void
2618 yyerror(char *s)
2619 {
2620 	char *cp;
2621 
2622 	if ((cp = strchr(cbuf,'\n')))
2623 		*cp = '\0';
2624 	reply(500, "%s: command not understood.", cbuf);
2625 }
2626 
2627 void
2628 delete(char *name)
2629 {
2630 	struct stat st;
2631 
2632 	LOGCMD("delete", name);
2633 	if (lstat(name, &st) < 0) {
2634 		perror_reply(550, name);
2635 		return;
2636 	}
2637 	if (S_ISDIR(st.st_mode)) {
2638 		if (rmdir(name) < 0) {
2639 			perror_reply(550, name);
2640 			return;
2641 		}
2642 		goto done;
2643 	}
2644 	if (guest && noguestmod) {
2645 		reply(550, "Operation not permitted.");
2646 		return;
2647 	}
2648 	if (unlink(name) < 0) {
2649 		perror_reply(550, name);
2650 		return;
2651 	}
2652 done:
2653 	ack("DELE");
2654 }
2655 
2656 void
2657 cwd(char *path)
2658 {
2659 
2660 	if (chdir(path) < 0)
2661 		perror_reply(550, path);
2662 	else
2663 		ack("CWD");
2664 }
2665 
2666 void
2667 makedir(char *name)
2668 {
2669 	char *s;
2670 
2671 	LOGCMD("mkdir", name);
2672 	if (guest && noguestmkd)
2673 		reply(550, "Operation not permitted.");
2674 	else if (mkdir(name, 0777) < 0)
2675 		perror_reply(550, name);
2676 	else {
2677 		if ((s = doublequote(name)) == NULL)
2678 			fatalerror("Ran out of memory.");
2679 		reply(257, "\"%s\" directory created.", s);
2680 		free(s);
2681 	}
2682 }
2683 
2684 void
2685 removedir(char *name)
2686 {
2687 
2688 	LOGCMD("rmdir", name);
2689 	if (rmdir(name) < 0)
2690 		perror_reply(550, name);
2691 	else
2692 		ack("RMD");
2693 }
2694 
2695 void
2696 pwd(void)
2697 {
2698 	char *s, path[MAXPATHLEN + 1];
2699 
2700 	if (getcwd(path, sizeof(path)) == NULL)
2701 		perror_reply(550, "Get current directory");
2702 	else {
2703 		if ((s = doublequote(path)) == NULL)
2704 			fatalerror("Ran out of memory.");
2705 		reply(257, "\"%s\" is current directory.", s);
2706 		free(s);
2707 	}
2708 }
2709 
2710 char *
2711 renamefrom(char *name)
2712 {
2713 	struct stat st;
2714 
2715 	if (guest && noguestmod) {
2716 		reply(550, "Operation not permitted.");
2717 		return (NULL);
2718 	}
2719 	if (lstat(name, &st) < 0) {
2720 		perror_reply(550, name);
2721 		return (NULL);
2722 	}
2723 	reply(350, "File exists, ready for destination name.");
2724 	return (name);
2725 }
2726 
2727 void
2728 renamecmd(char *from, char *to)
2729 {
2730 	struct stat st;
2731 
2732 	LOGCMD2("rename", from, to);
2733 
2734 	if (guest && (stat(to, &st) == 0)) {
2735 		reply(550, "%s: permission denied.", to);
2736 		return;
2737 	}
2738 
2739 	if (rename(from, to) < 0)
2740 		perror_reply(550, "rename");
2741 	else
2742 		ack("RNTO");
2743 }
2744 
2745 static void
2746 dolog(struct sockaddr *who)
2747 {
2748 	char who_name[NI_MAXHOST];
2749 
2750 	realhostname_sa(remotehost, sizeof(remotehost) - 1, who, who->sa_len);
2751 	remotehost[sizeof(remotehost) - 1] = 0;
2752 	if (getnameinfo(who, who->sa_len,
2753 		who_name, sizeof(who_name) - 1, NULL, 0, NI_NUMERICHOST))
2754 			*who_name = 0;
2755 	who_name[sizeof(who_name) - 1] = 0;
2756 
2757 #ifdef SETPROCTITLE
2758 #ifdef VIRTUAL_HOSTING
2759 	if (thishost != firsthost)
2760 		snprintf(proctitle, sizeof(proctitle), "%s: connected (to %s)",
2761 			 remotehost, hostname);
2762 	else
2763 #endif
2764 		snprintf(proctitle, sizeof(proctitle), "%s: connected",
2765 			 remotehost);
2766 	setproctitle("%s", proctitle);
2767 #endif /* SETPROCTITLE */
2768 
2769 	if (logging) {
2770 #ifdef VIRTUAL_HOSTING
2771 		if (thishost != firsthost)
2772 			syslog(LOG_INFO, "connection from %s (%s) to %s",
2773 			       remotehost, who_name, hostname);
2774 		else
2775 #endif
2776 			syslog(LOG_INFO, "connection from %s (%s)",
2777 			       remotehost, who_name);
2778 	}
2779 }
2780 
2781 /*
2782  * Record logout in wtmp file
2783  * and exit with supplied status.
2784  */
2785 void
2786 dologout(int status)
2787 {
2788 
2789 	if (logged_in && dowtmp) {
2790 		(void) seteuid(0);
2791 #ifdef		LOGIN_CAP
2792  	        setusercontext(NULL, getpwuid(0), 0, LOGIN_SETALL & ~(LOGIN_SETLOGIN |
2793 		       LOGIN_SETUSER | LOGIN_SETGROUP | LOGIN_SETPATH |
2794 		       LOGIN_SETENV));
2795 #endif
2796 		ftpd_logwtmp(wtmpid, NULL, NULL);
2797 	}
2798 	/* beware of flushing buffers after a SIGPIPE */
2799 	_exit(status);
2800 }
2801 
2802 static void
2803 sigurg(int signo)
2804 {
2805 
2806 	recvurg = 1;
2807 }
2808 
2809 static void
2810 maskurg(int flag)
2811 {
2812 	int oerrno;
2813 	sigset_t sset;
2814 
2815 	if (!transflag) {
2816 		syslog(LOG_ERR, "Internal: maskurg() while no transfer");
2817 		return;
2818 	}
2819 	oerrno = errno;
2820 	sigemptyset(&sset);
2821 	sigaddset(&sset, SIGURG);
2822 	sigprocmask(flag ? SIG_BLOCK : SIG_UNBLOCK, &sset, NULL);
2823 	errno = oerrno;
2824 }
2825 
2826 static void
2827 flagxfer(int flag)
2828 {
2829 
2830 	if (flag) {
2831 		if (transflag)
2832 			syslog(LOG_ERR, "Internal: flagxfer(1): "
2833 					"transfer already under way");
2834 		transflag = 1;
2835 		maskurg(0);
2836 		recvurg = 0;
2837 	} else {
2838 		if (!transflag)
2839 			syslog(LOG_ERR, "Internal: flagxfer(0): "
2840 					"no active transfer");
2841 		maskurg(1);
2842 		transflag = 0;
2843 	}
2844 }
2845 
2846 /*
2847  * Returns 0 if OK to resume or -1 if abort requested.
2848  */
2849 static int
2850 myoob(void)
2851 {
2852 	char *cp;
2853 	int ret;
2854 
2855 	if (!transflag) {
2856 		syslog(LOG_ERR, "Internal: myoob() while no transfer");
2857 		return (0);
2858 	}
2859 	cp = tmpline;
2860 	ret = get_line(cp, 7, stdin);
2861 	if (ret == -1) {
2862 		reply(221, "You could at least say goodbye.");
2863 		dologout(0);
2864 	} else if (ret == -2) {
2865 		/* Ignore truncated command. */
2866 		return (0);
2867 	}
2868 	upper(cp);
2869 	if (strcmp(cp, "ABOR\r\n") == 0) {
2870 		tmpline[0] = '\0';
2871 		reply(426, "Transfer aborted. Data connection closed.");
2872 		reply(226, "Abort successful.");
2873 		return (-1);
2874 	}
2875 	if (strcmp(cp, "STAT\r\n") == 0) {
2876 		tmpline[0] = '\0';
2877 		if (file_size != -1)
2878 			reply(213, "Status: %jd of %jd bytes transferred.",
2879 				   (intmax_t)byte_count, (intmax_t)file_size);
2880 		else
2881 			reply(213, "Status: %jd bytes transferred.",
2882 				   (intmax_t)byte_count);
2883 	}
2884 	return (0);
2885 }
2886 
2887 /*
2888  * Note: a response of 425 is not mentioned as a possible response to
2889  *	the PASV command in RFC959. However, it has been blessed as
2890  *	a legitimate response by Jon Postel in a telephone conversation
2891  *	with Rick Adams on 25 Jan 89.
2892  */
2893 void
2894 passive(void)
2895 {
2896 	socklen_t len;
2897 	int on;
2898 	char *p, *a;
2899 
2900 	if (pdata >= 0)		/* close old port if one set */
2901 		close(pdata);
2902 
2903 	pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
2904 	if (pdata < 0) {
2905 		perror_reply(425, "Can't open passive connection");
2906 		return;
2907 	}
2908 	on = 1;
2909 	if (setsockopt(pdata, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
2910 		syslog(LOG_WARNING, "pdata setsockopt (SO_REUSEADDR): %m");
2911 
2912 	(void) seteuid(0);
2913 
2914 #ifdef IP_PORTRANGE
2915 	if (ctrl_addr.su_family == AF_INET) {
2916 	    on = restricted_data_ports ? IP_PORTRANGE_HIGH
2917 				       : IP_PORTRANGE_DEFAULT;
2918 
2919 	    if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE,
2920 			    &on, sizeof(on)) < 0)
2921 		    goto pasv_error;
2922 	}
2923 #endif
2924 #ifdef IPV6_PORTRANGE
2925 	if (ctrl_addr.su_family == AF_INET6) {
2926 	    on = restricted_data_ports ? IPV6_PORTRANGE_HIGH
2927 				       : IPV6_PORTRANGE_DEFAULT;
2928 
2929 	    if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE,
2930 			    &on, sizeof(on)) < 0)
2931 		    goto pasv_error;
2932 	}
2933 #endif
2934 
2935 	pasv_addr = ctrl_addr;
2936 	pasv_addr.su_port = 0;
2937 	if (bind(pdata, (struct sockaddr *)&pasv_addr, pasv_addr.su_len) < 0)
2938 		goto pasv_error;
2939 
2940 	(void) seteuid(pw->pw_uid);
2941 
2942 	len = sizeof(pasv_addr);
2943 	if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0)
2944 		goto pasv_error;
2945 	if (listen(pdata, 1) < 0)
2946 		goto pasv_error;
2947 	if (pasv_addr.su_family == AF_INET)
2948 		a = (char *) &pasv_addr.su_sin.sin_addr;
2949 	else if (pasv_addr.su_family == AF_INET6 &&
2950 		 IN6_IS_ADDR_V4MAPPED(&pasv_addr.su_sin6.sin6_addr))
2951 		a = (char *) &pasv_addr.su_sin6.sin6_addr.s6_addr[12];
2952 	else
2953 		goto pasv_error;
2954 
2955 	p = (char *) &pasv_addr.su_port;
2956 
2957 #define UC(b) (((int) b) & 0xff)
2958 
2959 	reply(227, "Entering Passive Mode (%d,%d,%d,%d,%d,%d)", UC(a[0]),
2960 		UC(a[1]), UC(a[2]), UC(a[3]), UC(p[0]), UC(p[1]));
2961 	return;
2962 
2963 pasv_error:
2964 	(void) seteuid(pw->pw_uid);
2965 	(void) close(pdata);
2966 	pdata = -1;
2967 	perror_reply(425, "Can't open passive connection");
2968 	return;
2969 }
2970 
2971 /*
2972  * Long Passive defined in RFC 1639.
2973  *     228 Entering Long Passive Mode
2974  *         (af, hal, h1, h2, h3,..., pal, p1, p2...)
2975  */
2976 
2977 void
2978 long_passive(char *cmd, int pf)
2979 {
2980 	socklen_t len;
2981 	int on;
2982 	char *p, *a;
2983 
2984 	if (pdata >= 0)		/* close old port if one set */
2985 		close(pdata);
2986 
2987 	if (pf != PF_UNSPEC) {
2988 		if (ctrl_addr.su_family != pf) {
2989 			switch (ctrl_addr.su_family) {
2990 			case AF_INET:
2991 				pf = 1;
2992 				break;
2993 			case AF_INET6:
2994 				pf = 2;
2995 				break;
2996 			default:
2997 				pf = 0;
2998 				break;
2999 			}
3000 			/*
3001 			 * XXX
3002 			 * only EPRT/EPSV ready clients will understand this
3003 			 */
3004 			if (strcmp(cmd, "EPSV") == 0 && pf) {
3005 				reply(522, "Network protocol mismatch, "
3006 					"use (%d)", pf);
3007 			} else
3008 				reply(501, "Network protocol mismatch."); /*XXX*/
3009 
3010 			return;
3011 		}
3012 	}
3013 
3014 	pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
3015 	if (pdata < 0) {
3016 		perror_reply(425, "Can't open passive connection");
3017 		return;
3018 	}
3019 	on = 1;
3020 	if (setsockopt(pdata, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
3021 		syslog(LOG_WARNING, "pdata setsockopt (SO_REUSEADDR): %m");
3022 
3023 	(void) seteuid(0);
3024 
3025 	pasv_addr = ctrl_addr;
3026 	pasv_addr.su_port = 0;
3027 	len = pasv_addr.su_len;
3028 
3029 #ifdef IP_PORTRANGE
3030 	if (ctrl_addr.su_family == AF_INET) {
3031 	    on = restricted_data_ports ? IP_PORTRANGE_HIGH
3032 				       : IP_PORTRANGE_DEFAULT;
3033 
3034 	    if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE,
3035 			    &on, sizeof(on)) < 0)
3036 		    goto pasv_error;
3037 	}
3038 #endif
3039 #ifdef IPV6_PORTRANGE
3040 	if (ctrl_addr.su_family == AF_INET6) {
3041 	    on = restricted_data_ports ? IPV6_PORTRANGE_HIGH
3042 				       : IPV6_PORTRANGE_DEFAULT;
3043 
3044 	    if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE,
3045 			    &on, sizeof(on)) < 0)
3046 		    goto pasv_error;
3047 	}
3048 #endif
3049 
3050 	if (bind(pdata, (struct sockaddr *)&pasv_addr, len) < 0)
3051 		goto pasv_error;
3052 
3053 	(void) seteuid(pw->pw_uid);
3054 
3055 	if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0)
3056 		goto pasv_error;
3057 	if (listen(pdata, 1) < 0)
3058 		goto pasv_error;
3059 
3060 #define UC(b) (((int) b) & 0xff)
3061 
3062 	if (strcmp(cmd, "LPSV") == 0) {
3063 		p = (char *)&pasv_addr.su_port;
3064 		switch (pasv_addr.su_family) {
3065 		case AF_INET:
3066 			a = (char *) &pasv_addr.su_sin.sin_addr;
3067 		v4_reply:
3068 			reply(228,
3069 "Entering Long Passive Mode (%d,%d,%d,%d,%d,%d,%d,%d,%d)",
3070 			      4, 4, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
3071 			      2, UC(p[0]), UC(p[1]));
3072 			return;
3073 		case AF_INET6:
3074 			if (IN6_IS_ADDR_V4MAPPED(&pasv_addr.su_sin6.sin6_addr)) {
3075 				a = (char *) &pasv_addr.su_sin6.sin6_addr.s6_addr[12];
3076 				goto v4_reply;
3077 			}
3078 			a = (char *) &pasv_addr.su_sin6.sin6_addr;
3079 			reply(228,
3080 "Entering Long Passive Mode "
3081 "(%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d)",
3082 			      6, 16, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
3083 			      UC(a[4]), UC(a[5]), UC(a[6]), UC(a[7]),
3084 			      UC(a[8]), UC(a[9]), UC(a[10]), UC(a[11]),
3085 			      UC(a[12]), UC(a[13]), UC(a[14]), UC(a[15]),
3086 			      2, UC(p[0]), UC(p[1]));
3087 			return;
3088 		}
3089 	} else if (strcmp(cmd, "EPSV") == 0) {
3090 		switch (pasv_addr.su_family) {
3091 		case AF_INET:
3092 		case AF_INET6:
3093 			reply(229, "Entering Extended Passive Mode (|||%d|)",
3094 				ntohs(pasv_addr.su_port));
3095 			return;
3096 		}
3097 	} else {
3098 		/* more proper error code? */
3099 	}
3100 
3101 pasv_error:
3102 	(void) seteuid(pw->pw_uid);
3103 	(void) close(pdata);
3104 	pdata = -1;
3105 	perror_reply(425, "Can't open passive connection");
3106 	return;
3107 }
3108 
3109 /*
3110  * Generate unique name for file with basename "local"
3111  * and open the file in order to avoid possible races.
3112  * Try "local" first, then "local.1", "local.2" etc, up to "local.99".
3113  * Return descriptor to the file, set "name" to its name.
3114  *
3115  * Generates failure reply on error.
3116  */
3117 static int
3118 guniquefd(char *local, char **name)
3119 {
3120 	static char new[MAXPATHLEN];
3121 	struct stat st;
3122 	char *cp;
3123 	int count;
3124 	int fd;
3125 
3126 	cp = strrchr(local, '/');
3127 	if (cp)
3128 		*cp = '\0';
3129 	if (stat(cp ? local : ".", &st) < 0) {
3130 		perror_reply(553, cp ? local : ".");
3131 		return (-1);
3132 	}
3133 	if (cp) {
3134 		/*
3135 		 * Let not overwrite dirname with counter suffix.
3136 		 * -4 is for /nn\0
3137 		 * In this extreme case dot won't be put in front of suffix.
3138 		 */
3139 		if (strlen(local) > sizeof(new) - 4) {
3140 			reply(553, "Pathname too long.");
3141 			return (-1);
3142 		}
3143 		*cp = '/';
3144 	}
3145 	/* -4 is for the .nn<null> we put on the end below */
3146 	(void) snprintf(new, sizeof(new) - 4, "%s", local);
3147 	cp = new + strlen(new);
3148 	/*
3149 	 * Don't generate dotfile unless requested explicitly.
3150 	 * This covers the case when basename gets truncated off
3151 	 * by buffer size.
3152 	 */
3153 	if (cp > new && cp[-1] != '/')
3154 		*cp++ = '.';
3155 	for (count = 0; count < 100; count++) {
3156 		/* At count 0 try unmodified name */
3157 		if (count)
3158 			(void)sprintf(cp, "%d", count);
3159 		if ((fd = open(count ? new : local,
3160 		    O_RDWR | O_CREAT | O_EXCL, 0666)) >= 0) {
3161 			*name = count ? new : local;
3162 			return (fd);
3163 		}
3164 		if (errno != EEXIST) {
3165 			perror_reply(553, count ? new : local);
3166 			return (-1);
3167 		}
3168 	}
3169 	reply(452, "Unique file name cannot be created.");
3170 	return (-1);
3171 }
3172 
3173 /*
3174  * Format and send reply containing system error number.
3175  */
3176 void
3177 perror_reply(int code, char *string)
3178 {
3179 
3180 	reply(code, "%s: %s.", string, strerror(errno));
3181 }
3182 
3183 static char *onefile[] = {
3184 	"",
3185 	0
3186 };
3187 
3188 void
3189 send_file_list(char *whichf)
3190 {
3191 	struct stat st;
3192 	DIR *dirp = NULL;
3193 	struct dirent *dir;
3194 	FILE *dout = NULL;
3195 	char **dirlist, *dirname;
3196 	int simple = 0;
3197 	int freeglob = 0;
3198 	glob_t gl;
3199 
3200 	if (strpbrk(whichf, "~{[*?") != NULL) {
3201 		int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE;
3202 
3203 		memset(&gl, 0, sizeof(gl));
3204 		gl.gl_matchc = MAXGLOBARGS;
3205 		flags |= GLOB_LIMIT;
3206 		freeglob = 1;
3207 		if (glob(whichf, flags, 0, &gl)) {
3208 			reply(550, "No matching files found.");
3209 			goto out;
3210 		} else if (gl.gl_pathc == 0) {
3211 			errno = ENOENT;
3212 			perror_reply(550, whichf);
3213 			goto out;
3214 		}
3215 		dirlist = gl.gl_pathv;
3216 	} else {
3217 		onefile[0] = whichf;
3218 		dirlist = onefile;
3219 		simple = 1;
3220 	}
3221 
3222 	while ((dirname = *dirlist++)) {
3223 		if (stat(dirname, &st) < 0) {
3224 			/*
3225 			 * If user typed "ls -l", etc, and the client
3226 			 * used NLST, do what the user meant.
3227 			 */
3228 			if (dirname[0] == '-' && *dirlist == NULL &&
3229 			    dout == NULL)
3230 				retrieve(_PATH_LS " %s", dirname);
3231 			else
3232 				perror_reply(550, whichf);
3233 			goto out;
3234 		}
3235 
3236 		if (S_ISREG(st.st_mode)) {
3237 			if (dout == NULL) {
3238 				dout = dataconn("file list", -1, "w");
3239 				if (dout == NULL)
3240 					goto out;
3241 				STARTXFER;
3242 			}
3243 			START_UNSAFE;
3244 			fprintf(dout, "%s%s\n", dirname,
3245 				type == TYPE_A ? "\r" : "");
3246 			END_UNSAFE;
3247 			if (ferror(dout))
3248 				goto data_err;
3249 			byte_count += strlen(dirname) +
3250 				      (type == TYPE_A ? 2 : 1);
3251 			CHECKOOB(goto abrt);
3252 			continue;
3253 		} else if (!S_ISDIR(st.st_mode))
3254 			continue;
3255 
3256 		if ((dirp = opendir(dirname)) == NULL)
3257 			continue;
3258 
3259 		while ((dir = readdir(dirp)) != NULL) {
3260 			char nbuf[MAXPATHLEN];
3261 
3262 			CHECKOOB(goto abrt);
3263 
3264 			if (dir->d_name[0] == '.' && dir->d_namlen == 1)
3265 				continue;
3266 			if (dir->d_name[0] == '.' && dir->d_name[1] == '.' &&
3267 			    dir->d_namlen == 2)
3268 				continue;
3269 
3270 			snprintf(nbuf, sizeof(nbuf),
3271 				"%s/%s", dirname, dir->d_name);
3272 
3273 			/*
3274 			 * We have to do a stat to insure it's
3275 			 * not a directory or special file.
3276 			 */
3277 			if (simple || (stat(nbuf, &st) == 0 &&
3278 			    S_ISREG(st.st_mode))) {
3279 				if (dout == NULL) {
3280 					dout = dataconn("file list", -1, "w");
3281 					if (dout == NULL)
3282 						goto out;
3283 					STARTXFER;
3284 				}
3285 				START_UNSAFE;
3286 				if (nbuf[0] == '.' && nbuf[1] == '/')
3287 					fprintf(dout, "%s%s\n", &nbuf[2],
3288 						type == TYPE_A ? "\r" : "");
3289 				else
3290 					fprintf(dout, "%s%s\n", nbuf,
3291 						type == TYPE_A ? "\r" : "");
3292 				END_UNSAFE;
3293 				if (ferror(dout))
3294 					goto data_err;
3295 				byte_count += strlen(nbuf) +
3296 					      (type == TYPE_A ? 2 : 1);
3297 				CHECKOOB(goto abrt);
3298 			}
3299 		}
3300 		(void) closedir(dirp);
3301 		dirp = NULL;
3302 	}
3303 
3304 	if (dout == NULL)
3305 		reply(550, "No files found.");
3306 	else if (ferror(dout))
3307 data_err:	perror_reply(550, "Data connection");
3308 	else
3309 		reply(226, "Transfer complete.");
3310 out:
3311 	if (dout) {
3312 		ENDXFER;
3313 abrt:
3314 		(void) fclose(dout);
3315 		data = -1;
3316 		pdata = -1;
3317 	}
3318 	if (dirp)
3319 		(void) closedir(dirp);
3320 	if (freeglob) {
3321 		freeglob = 0;
3322 		globfree(&gl);
3323 	}
3324 }
3325 
3326 void
3327 reapchild(int signo)
3328 {
3329 	while (waitpid(-1, NULL, WNOHANG) > 0);
3330 }
3331 
3332 #ifdef OLD_SETPROCTITLE
3333 /*
3334  * Clobber argv so ps will show what we're doing.  (Stolen from sendmail.)
3335  * Warning, since this is usually started from inetd.conf, it often doesn't
3336  * have much of an environment or arglist to overwrite.
3337  */
3338 void
3339 setproctitle(const char *fmt, ...)
3340 {
3341 	int i;
3342 	va_list ap;
3343 	char *p, *bp, ch;
3344 	char buf[LINE_MAX];
3345 
3346 	va_start(ap, fmt);
3347 	(void)vsnprintf(buf, sizeof(buf), fmt, ap);
3348 
3349 	/* make ps print our process name */
3350 	p = Argv[0];
3351 	*p++ = '-';
3352 
3353 	i = strlen(buf);
3354 	if (i > LastArgv - p - 2) {
3355 		i = LastArgv - p - 2;
3356 		buf[i] = '\0';
3357 	}
3358 	bp = buf;
3359 	while (ch = *bp++)
3360 		if (ch != '\n' && ch != '\r')
3361 			*p++ = ch;
3362 	while (p < LastArgv)
3363 		*p++ = ' ';
3364 }
3365 #endif /* OLD_SETPROCTITLE */
3366 
3367 static void
3368 appendf(char **strp, char *fmt, ...)
3369 {
3370 	va_list ap;
3371 	char *ostr, *p;
3372 
3373 	va_start(ap, fmt);
3374 	vasprintf(&p, fmt, ap);
3375 	va_end(ap);
3376 	if (p == NULL)
3377 		fatalerror("Ran out of memory.");
3378 	if (*strp == NULL)
3379 		*strp = p;
3380 	else {
3381 		ostr = *strp;
3382 		asprintf(strp, "%s%s", ostr, p);
3383 		if (*strp == NULL)
3384 			fatalerror("Ran out of memory.");
3385 		free(ostr);
3386 	}
3387 }
3388 
3389 static void
3390 logcmd(char *cmd, char *file1, char *file2, off_t cnt)
3391 {
3392 	char *msg = NULL;
3393 	char wd[MAXPATHLEN + 1];
3394 
3395 	if (logging <= 1)
3396 		return;
3397 
3398 	if (getcwd(wd, sizeof(wd) - 1) == NULL)
3399 		strcpy(wd, strerror(errno));
3400 
3401 	appendf(&msg, "%s", cmd);
3402 	if (file1)
3403 		appendf(&msg, " %s", file1);
3404 	if (file2)
3405 		appendf(&msg, " %s", file2);
3406 	if (cnt >= 0)
3407 		appendf(&msg, " = %jd bytes", (intmax_t)cnt);
3408 	appendf(&msg, " (wd: %s", wd);
3409 	if (guest || dochroot)
3410 		appendf(&msg, "; chrooted");
3411 	appendf(&msg, ")");
3412 	syslog(LOG_INFO, "%s", msg);
3413 	free(msg);
3414 }
3415 
3416 static void
3417 logxfer(char *name, off_t size, time_t start)
3418 {
3419 	char buf[MAXPATHLEN + 1024];
3420 	char path[MAXPATHLEN + 1];
3421 	time_t now;
3422 
3423 	if (statfd >= 0) {
3424 		time(&now);
3425 		if (realpath(name, path) == NULL) {
3426 			syslog(LOG_NOTICE, "realpath failed on %s: %m", path);
3427 			return;
3428 		}
3429 		snprintf(buf, sizeof(buf), "%.20s!%s!%s!%s!%jd!%ld\n",
3430 			ctime(&now)+4, ident, remotehost,
3431 			path, (intmax_t)size,
3432 			(long)(now - start + (now == start)));
3433 		write(statfd, buf, strlen(buf));
3434 	}
3435 }
3436 
3437 static char *
3438 doublequote(char *s)
3439 {
3440 	int n;
3441 	char *p, *s2;
3442 
3443 	for (p = s, n = 0; *p; p++)
3444 		if (*p == '"')
3445 			n++;
3446 
3447 	if ((s2 = malloc(p - s + n + 1)) == NULL)
3448 		return (NULL);
3449 
3450 	for (p = s2; *s; s++, p++) {
3451 		if ((*p = *s) == '"')
3452 			*(++p) = '"';
3453 	}
3454 	*p = '\0';
3455 
3456 	return (s2);
3457 }
3458 
3459 /* setup server socket for specified address family */
3460 /* if af is PF_UNSPEC more than one socket may be returned */
3461 /* the returned list is dynamically allocated, so caller needs to free it */
3462 static int *
3463 socksetup(int af, char *bindname, const char *bindport)
3464 {
3465 	struct addrinfo hints, *res, *r;
3466 	int error, maxs, *s, *socks;
3467 	const int on = 1;
3468 
3469 	memset(&hints, 0, sizeof(hints));
3470 	hints.ai_flags = AI_PASSIVE;
3471 	hints.ai_family = af;
3472 	hints.ai_socktype = SOCK_STREAM;
3473 	error = getaddrinfo(bindname, bindport, &hints, &res);
3474 	if (error) {
3475 		syslog(LOG_ERR, "%s", gai_strerror(error));
3476 		if (error == EAI_SYSTEM)
3477 			syslog(LOG_ERR, "%s", strerror(errno));
3478 		return NULL;
3479 	}
3480 
3481 	/* Count max number of sockets we may open */
3482 	for (maxs = 0, r = res; r; r = r->ai_next, maxs++)
3483 		;
3484 	socks = malloc((maxs + 1) * sizeof(int));
3485 	if (!socks) {
3486 		freeaddrinfo(res);
3487 		syslog(LOG_ERR, "couldn't allocate memory for sockets");
3488 		return NULL;
3489 	}
3490 
3491 	*socks = 0;   /* num of sockets counter at start of array */
3492 	s = socks + 1;
3493 	for (r = res; r; r = r->ai_next) {
3494 		*s = socket(r->ai_family, r->ai_socktype, r->ai_protocol);
3495 		if (*s < 0) {
3496 			syslog(LOG_DEBUG, "control socket: %m");
3497 			continue;
3498 		}
3499 		if (setsockopt(*s, SOL_SOCKET, SO_REUSEADDR,
3500 		    &on, sizeof(on)) < 0)
3501 			syslog(LOG_WARNING,
3502 			    "control setsockopt (SO_REUSEADDR): %m");
3503 		if (r->ai_family == AF_INET6) {
3504 			if (setsockopt(*s, IPPROTO_IPV6, IPV6_V6ONLY,
3505 			    &on, sizeof(on)) < 0)
3506 				syslog(LOG_WARNING,
3507 				    "control setsockopt (IPV6_V6ONLY): %m");
3508 		}
3509 		if (bind(*s, r->ai_addr, r->ai_addrlen) < 0) {
3510 			syslog(LOG_DEBUG, "control bind: %m");
3511 			close(*s);
3512 			continue;
3513 		}
3514 		(*socks)++;
3515 		s++;
3516 	}
3517 
3518 	if (res)
3519 		freeaddrinfo(res);
3520 
3521 	if (*socks == 0) {
3522 		syslog(LOG_ERR, "control socket: Couldn't bind to any socket");
3523 		free(socks);
3524 		return NULL;
3525 	}
3526 	return(socks);
3527 }
3528