xref: /freebsd/libexec/ftpd/ftpd.c (revision 884a2a699669ec61e2366e3e358342dbc94be24a)
1 /*
2  * Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #if 0
35 #ifndef lint
36 static char copyright[] =
37 "@(#) Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994\n\
38 	The Regents of the University of California.  All rights reserved.\n";
39 #endif /* not lint */
40 #endif
41 
42 #ifndef lint
43 #if 0
44 static char sccsid[] = "@(#)ftpd.c	8.4 (Berkeley) 4/16/94";
45 #endif
46 #endif /* not lint */
47 
48 #include <sys/cdefs.h>
49 __FBSDID("$FreeBSD$");
50 
51 /*
52  * FTP server.
53  */
54 #include <sys/param.h>
55 #include <sys/ioctl.h>
56 #include <sys/mman.h>
57 #include <sys/socket.h>
58 #include <sys/stat.h>
59 #include <sys/time.h>
60 #include <sys/wait.h>
61 
62 #include <netinet/in.h>
63 #include <netinet/in_systm.h>
64 #include <netinet/ip.h>
65 #include <netinet/tcp.h>
66 
67 #define	FTP_NAMES
68 #include <arpa/ftp.h>
69 #include <arpa/inet.h>
70 #include <arpa/telnet.h>
71 
72 #include <ctype.h>
73 #include <dirent.h>
74 #include <err.h>
75 #include <errno.h>
76 #include <fcntl.h>
77 #include <glob.h>
78 #include <limits.h>
79 #include <netdb.h>
80 #include <pwd.h>
81 #include <grp.h>
82 #include <opie.h>
83 #include <signal.h>
84 #include <stdint.h>
85 #include <stdio.h>
86 #include <stdlib.h>
87 #include <string.h>
88 #include <syslog.h>
89 #include <time.h>
90 #include <unistd.h>
91 #include <libutil.h>
92 #ifdef	LOGIN_CAP
93 #include <login_cap.h>
94 #endif
95 
96 #ifdef USE_PAM
97 #include <security/pam_appl.h>
98 #endif
99 
100 #include "pathnames.h"
101 #include "extern.h"
102 
103 #include <stdarg.h>
104 
105 static char version[] = "Version 6.00LS";
106 #undef main
107 
108 union sockunion ctrl_addr;
109 union sockunion data_source;
110 union sockunion data_dest;
111 union sockunion his_addr;
112 union sockunion pasv_addr;
113 
114 int	daemon_mode;
115 int	data;
116 int	dataport;
117 int	hostinfo = 1;	/* print host-specific info in messages */
118 int	logged_in;
119 struct	passwd *pw;
120 char	*homedir;
121 int	ftpdebug;
122 int	timeout = 900;    /* timeout after 15 minutes of inactivity */
123 int	maxtimeout = 7200;/* don't allow idle time to be set beyond 2 hours */
124 int	logging;
125 int	restricted_data_ports = 1;
126 int	paranoid = 1;	  /* be extra careful about security */
127 int	anon_only = 0;    /* Only anonymous ftp allowed */
128 int	assumeutf8 = 0;   /* Assume that server file names are in UTF-8 */
129 int	guest;
130 int	dochroot;
131 char	*chrootdir;
132 int	dowtmp = 1;
133 int	stats;
134 int	statfd = -1;
135 int	type;
136 int	form;
137 int	stru;			/* avoid C keyword */
138 int	mode;
139 int	usedefault = 1;		/* for data transfers */
140 int	pdata = -1;		/* for passive mode */
141 int	readonly = 0;		/* Server is in readonly mode.	*/
142 int	noepsv = 0;		/* EPSV command is disabled.	*/
143 int	noretr = 0;		/* RETR command is disabled.	*/
144 int	noguestretr = 0;	/* RETR command is disabled for anon users. */
145 int	noguestmkd = 0;		/* MKD command is disabled for anon users. */
146 int	noguestmod = 1;		/* anon users may not modify existing files. */
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;
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:AdDEhlmMoOp: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 'd':
331 			ftpdebug++;
332 			break;
333 
334 		case 'D':
335 			daemon_mode++;
336 			break;
337 
338 		case 'E':
339 			noepsv = 1;
340 			break;
341 
342 		case 'h':
343 			hostinfo = 0;
344 			break;
345 
346 		case 'l':
347 			logging++;	/* > 1 == extra logging */
348 			break;
349 
350 		case 'm':
351 			noguestmod = 0;
352 			break;
353 
354 		case 'M':
355 			noguestmkd = 1;
356 			break;
357 
358 		case 'o':
359 			noretr = 1;
360 			break;
361 
362 		case 'O':
363 			noguestretr = 1;
364 			break;
365 
366 		case 'p':
367 			pid_file = optarg;
368 			break;
369 
370 		case 'P':
371 			bindport = optarg;
372 			break;
373 
374 		case 'r':
375 			readonly = 1;
376 			break;
377 
378 		case 'R':
379 			paranoid = 0;
380 			break;
381 
382 		case 'S':
383 			stats++;
384 			break;
385 
386 		case 't':
387 			timeout = atoi(optarg);
388 			if (maxtimeout < timeout)
389 				maxtimeout = timeout;
390 			break;
391 
392 		case 'T':
393 			maxtimeout = atoi(optarg);
394 			if (timeout > maxtimeout)
395 				timeout = maxtimeout;
396 			break;
397 
398 		case 'u':
399 		    {
400 			long val = 0;
401 
402 			val = strtol(optarg, &optarg, 8);
403 			if (*optarg != '\0' || val < 0)
404 				syslog(LOG_WARNING, "bad value for -u");
405 			else
406 				defumask = val;
407 			break;
408 		    }
409 		case 'U':
410 			restricted_data_ports = 0;
411 			break;
412 
413 		case 'v':
414 			ftpdebug++;
415 			break;
416 
417 		case 'W':
418 			dowtmp = 0;
419 			break;
420 
421 		default:
422 			syslog(LOG_WARNING, "unknown flag -%c ignored", optopt);
423 			break;
424 		}
425 	}
426 
427 	if (daemon_mode) {
428 		int *ctl_sock, fd, maxfd = -1, nfds, i;
429 		fd_set defreadfds, readfds;
430 		pid_t pid;
431 		struct pidfh *pfh;
432 
433 		if ((pfh = pidfile_open(pid_file, 0600, &pid)) == NULL) {
434 			if (errno == EEXIST) {
435 				syslog(LOG_ERR, "%s already running, pid %d",
436 				       getprogname(), (int)pid);
437 				exit(1);
438 			}
439 			syslog(LOG_WARNING, "pidfile_open: %m");
440 		}
441 
442 		/*
443 		 * Detach from parent.
444 		 */
445 		if (daemon(1, 1) < 0) {
446 			syslog(LOG_ERR, "failed to become a daemon");
447 			exit(1);
448 		}
449 
450 		if (pfh != NULL && pidfile_write(pfh) == -1)
451 			syslog(LOG_WARNING, "pidfile_write: %m");
452 
453 		sa.sa_handler = reapchild;
454 		(void)sigaction(SIGCHLD, &sa, NULL);
455 
456 #ifdef VIRTUAL_HOSTING
457 		inithosts(family);
458 #endif
459 
460 		/*
461 		 * Open a socket, bind it to the FTP port, and start
462 		 * listening.
463 		 */
464 		ctl_sock = socksetup(family, bindname, bindport);
465 		if (ctl_sock == NULL)
466 			exit(1);
467 
468 		FD_ZERO(&defreadfds);
469 		for (i = 1; i <= *ctl_sock; i++) {
470 			FD_SET(ctl_sock[i], &defreadfds);
471 			if (listen(ctl_sock[i], 32) < 0) {
472 				syslog(LOG_ERR, "control listen: %m");
473 				exit(1);
474 			}
475 			if (maxfd < ctl_sock[i])
476 				maxfd = ctl_sock[i];
477 		}
478 
479 		/*
480 		 * Loop forever accepting connection requests and forking off
481 		 * children to handle them.
482 		 */
483 		while (1) {
484 			FD_COPY(&defreadfds, &readfds);
485 			nfds = select(maxfd + 1, &readfds, NULL, NULL, 0);
486 			if (nfds <= 0) {
487 				if (nfds < 0 && errno != EINTR)
488 					syslog(LOG_WARNING, "select: %m");
489 				continue;
490 			}
491 
492 			pid = -1;
493                         for (i = 1; i <= *ctl_sock; i++)
494 				if (FD_ISSET(ctl_sock[i], &readfds)) {
495 					addrlen = sizeof(his_addr);
496 					fd = accept(ctl_sock[i],
497 					    (struct sockaddr *)&his_addr,
498 					    &addrlen);
499 					if (fd == -1) {
500 						syslog(LOG_WARNING,
501 						       "accept: %m");
502 						continue;
503 					}
504 					switch (pid = fork()) {
505 					case 0:
506 						/* child */
507 						(void) dup2(fd, 0);
508 						(void) dup2(fd, 1);
509 						(void) close(fd);
510 						for (i = 1; i <= *ctl_sock; i++)
511 							close(ctl_sock[i]);
512 						if (pfh != NULL)
513 							pidfile_close(pfh);
514 						goto gotchild;
515 					case -1:
516 						syslog(LOG_WARNING, "fork: %m");
517 						/* FALLTHROUGH */
518 					default:
519 						close(fd);
520 					}
521 				}
522 		}
523 	} else {
524 		addrlen = sizeof(his_addr);
525 		if (getpeername(0, (struct sockaddr *)&his_addr, &addrlen) < 0) {
526 			syslog(LOG_ERR, "getpeername (%s): %m",argv[0]);
527 			exit(1);
528 		}
529 
530 #ifdef VIRTUAL_HOSTING
531 		if (his_addr.su_family == AF_INET6 &&
532 		    IN6_IS_ADDR_V4MAPPED(&his_addr.su_sin6.sin6_addr))
533 			family = AF_INET;
534 		else
535 			family = his_addr.su_family;
536 		inithosts(family);
537 #endif
538 	}
539 
540 gotchild:
541 	sa.sa_handler = SIG_DFL;
542 	(void)sigaction(SIGCHLD, &sa, NULL);
543 
544 	sa.sa_handler = sigurg;
545 	sa.sa_flags = 0;		/* don't restart syscalls for SIGURG */
546 	(void)sigaction(SIGURG, &sa, NULL);
547 
548 	sigfillset(&sa.sa_mask);	/* block all signals in handler */
549 	sa.sa_flags = SA_RESTART;
550 	sa.sa_handler = sigquit;
551 	(void)sigaction(SIGHUP, &sa, NULL);
552 	(void)sigaction(SIGINT, &sa, NULL);
553 	(void)sigaction(SIGQUIT, &sa, NULL);
554 	(void)sigaction(SIGTERM, &sa, NULL);
555 
556 	sa.sa_handler = lostconn;
557 	(void)sigaction(SIGPIPE, &sa, NULL);
558 
559 	addrlen = sizeof(ctrl_addr);
560 	if (getsockname(0, (struct sockaddr *)&ctrl_addr, &addrlen) < 0) {
561 		syslog(LOG_ERR, "getsockname (%s): %m",argv[0]);
562 		exit(1);
563 	}
564 	dataport = ntohs(ctrl_addr.su_port) - 1; /* as per RFC 959 */
565 #ifdef VIRTUAL_HOSTING
566 	/* select our identity from virtual host table */
567 	selecthost(&ctrl_addr);
568 #endif
569 #ifdef IP_TOS
570 	if (ctrl_addr.su_family == AF_INET)
571       {
572 	tos = IPTOS_LOWDELAY;
573 	if (setsockopt(0, IPPROTO_IP, IP_TOS, &tos, sizeof(int)) < 0)
574 		syslog(LOG_WARNING, "control setsockopt (IP_TOS): %m");
575       }
576 #endif
577 	/*
578 	 * Disable Nagle on the control channel so that we don't have to wait
579 	 * for peer's ACK before issuing our next reply.
580 	 */
581 	if (setsockopt(0, IPPROTO_TCP, TCP_NODELAY, &on, sizeof(on)) < 0)
582 		syslog(LOG_WARNING, "control setsockopt (TCP_NODELAY): %m");
583 
584 	data_source.su_port = htons(ntohs(ctrl_addr.su_port) - 1);
585 
586 	(void)snprintf(wtmpid, sizeof(wtmpid), "%xftpd", getpid());
587 
588 	/* Try to handle urgent data inline */
589 #ifdef SO_OOBINLINE
590 	if (setsockopt(0, SOL_SOCKET, SO_OOBINLINE, &on, sizeof(on)) < 0)
591 		syslog(LOG_WARNING, "control setsockopt (SO_OOBINLINE): %m");
592 #endif
593 
594 #ifdef	F_SETOWN
595 	if (fcntl(fileno(stdin), F_SETOWN, getpid()) == -1)
596 		syslog(LOG_ERR, "fcntl F_SETOWN: %m");
597 #endif
598 	dolog((struct sockaddr *)&his_addr);
599 	/*
600 	 * Set up default state
601 	 */
602 	data = -1;
603 	type = TYPE_A;
604 	form = FORM_N;
605 	stru = STRU_F;
606 	mode = MODE_S;
607 	tmpline[0] = '\0';
608 
609 	/* If logins are disabled, print out the message. */
610 	if ((fd = fopen(_PATH_NOLOGIN,"r")) != NULL) {
611 		while (fgets(line, sizeof(line), fd) != NULL) {
612 			if ((cp = strchr(line, '\n')) != NULL)
613 				*cp = '\0';
614 			lreply(530, "%s", line);
615 		}
616 		(void) fflush(stdout);
617 		(void) fclose(fd);
618 		reply(530, "System not available.");
619 		exit(0);
620 	}
621 #ifdef VIRTUAL_HOSTING
622 	fd = fopen(thishost->welcome, "r");
623 #else
624 	fd = fopen(_PATH_FTPWELCOME, "r");
625 #endif
626 	if (fd != NULL) {
627 		while (fgets(line, sizeof(line), fd) != NULL) {
628 			if ((cp = strchr(line, '\n')) != NULL)
629 				*cp = '\0';
630 			lreply(220, "%s", line);
631 		}
632 		(void) fflush(stdout);
633 		(void) fclose(fd);
634 		/* reply(220,) must follow */
635 	}
636 #ifndef VIRTUAL_HOSTING
637 	if ((hostname = malloc(MAXHOSTNAMELEN)) == NULL)
638 		fatalerror("Ran out of memory.");
639 	if (gethostname(hostname, MAXHOSTNAMELEN - 1) < 0)
640 		hostname[0] = '\0';
641 	hostname[MAXHOSTNAMELEN - 1] = '\0';
642 #endif
643 	if (hostinfo)
644 		reply(220, "%s FTP server (%s) ready.", hostname, version);
645 	else
646 		reply(220, "FTP server ready.");
647 	for (;;)
648 		(void) yyparse();
649 	/* NOTREACHED */
650 }
651 
652 static void
653 lostconn(int signo)
654 {
655 
656 	if (ftpdebug)
657 		syslog(LOG_DEBUG, "lost connection");
658 	dologout(1);
659 }
660 
661 static void
662 sigquit(int signo)
663 {
664 
665 	syslog(LOG_ERR, "got signal %d", signo);
666 	dologout(1);
667 }
668 
669 #ifdef VIRTUAL_HOSTING
670 /*
671  * read in virtual host tables (if they exist)
672  */
673 
674 static void
675 inithosts(int family)
676 {
677 	int insert;
678 	size_t len;
679 	FILE *fp;
680 	char *cp, *mp, *line;
681 	char *hostname;
682 	char *vhost, *anonuser, *statfile, *welcome, *loginmsg;
683 	struct ftphost *hrp, *lhrp;
684 	struct addrinfo hints, *res, *ai;
685 
686 	/*
687 	 * Fill in the default host information
688 	 */
689 	if ((hostname = malloc(MAXHOSTNAMELEN)) == NULL)
690 		fatalerror("Ran out of memory.");
691 	if (gethostname(hostname, MAXHOSTNAMELEN - 1) < 0)
692 		hostname[0] = '\0';
693 	hostname[MAXHOSTNAMELEN - 1] = '\0';
694 	if ((hrp = malloc(sizeof(struct ftphost))) == NULL)
695 		fatalerror("Ran out of memory.");
696 	hrp->hostname = hostname;
697 	hrp->hostinfo = NULL;
698 
699 	memset(&hints, 0, sizeof(hints));
700 	hints.ai_flags = AI_PASSIVE;
701 	hints.ai_family = family;
702 	hints.ai_socktype = SOCK_STREAM;
703 	if (getaddrinfo(hrp->hostname, NULL, &hints, &res) == 0)
704 		hrp->hostinfo = res;
705 	hrp->statfile = _PATH_FTPDSTATFILE;
706 	hrp->welcome  = _PATH_FTPWELCOME;
707 	hrp->loginmsg = _PATH_FTPLOGINMESG;
708 	hrp->anonuser = "ftp";
709 	hrp->next = NULL;
710 	thishost = firsthost = lhrp = hrp;
711 	if ((fp = fopen(_PATH_FTPHOSTS, "r")) != NULL) {
712 		int addrsize, gothost;
713 		void *addr;
714 		struct hostent *hp;
715 
716 		while ((line = fgetln(fp, &len)) != NULL) {
717 			int	i, hp_error;
718 
719 			/* skip comments */
720 			if (line[0] == '#')
721 				continue;
722 			if (line[len - 1] == '\n') {
723 				line[len - 1] = '\0';
724 				mp = NULL;
725 			} else {
726 				if ((mp = malloc(len + 1)) == NULL)
727 					fatalerror("Ran out of memory.");
728 				memcpy(mp, line, len);
729 				mp[len] = '\0';
730 				line = mp;
731 			}
732 			cp = strtok(line, " \t");
733 			/* skip empty lines */
734 			if (cp == NULL)
735 				goto nextline;
736 			vhost = cp;
737 
738 			/* set defaults */
739 			anonuser = "ftp";
740 			statfile = _PATH_FTPDSTATFILE;
741 			welcome  = _PATH_FTPWELCOME;
742 			loginmsg = _PATH_FTPLOGINMESG;
743 
744 			/*
745 			 * Preparse the line so we can use its info
746 			 * for all the addresses associated with
747 			 * the virtual host name.
748 			 * Field 0, the virtual host name, is special:
749 			 * it's already parsed off and will be strdup'ed
750 			 * later, after we know its canonical form.
751 			 */
752 			for (i = 1; i < 5 && (cp = strtok(NULL, " \t")); i++)
753 				if (*cp != '-' && (cp = strdup(cp)))
754 					switch (i) {
755 					case 1:	/* anon user permissions */
756 						anonuser = cp;
757 						break;
758 					case 2: /* statistics file */
759 						statfile = cp;
760 						break;
761 					case 3: /* welcome message */
762 						welcome  = cp;
763 						break;
764 					case 4: /* login message */
765 						loginmsg = cp;
766 						break;
767 					default: /* programming error */
768 						abort();
769 						/* NOTREACHED */
770 					}
771 
772 			hints.ai_flags = AI_PASSIVE;
773 			hints.ai_family = family;
774 			hints.ai_socktype = SOCK_STREAM;
775 			if (getaddrinfo(vhost, NULL, &hints, &res) != 0)
776 				goto nextline;
777 			for (ai = res; ai != NULL && ai->ai_addr != NULL;
778 			     ai = ai->ai_next) {
779 
780 			gothost = 0;
781 			for (hrp = firsthost; hrp != NULL; hrp = hrp->next) {
782 				struct addrinfo *hi;
783 
784 				for (hi = hrp->hostinfo; hi != NULL;
785 				     hi = hi->ai_next)
786 					if (hi->ai_addrlen == ai->ai_addrlen &&
787 					    memcmp(hi->ai_addr,
788 						   ai->ai_addr,
789 						   ai->ai_addr->sa_len) == 0) {
790 						gothost++;
791 						break;
792 					}
793 				if (gothost)
794 					break;
795 			}
796 			if (hrp == NULL) {
797 				if ((hrp = malloc(sizeof(struct ftphost))) == NULL)
798 					goto nextline;
799 				hrp->hostname = NULL;
800 				insert = 1;
801 			} else {
802 				if (hrp->hostinfo && hrp->hostinfo != res)
803 					freeaddrinfo(hrp->hostinfo);
804 				insert = 0; /* host already in the chain */
805 			}
806 			hrp->hostinfo = res;
807 
808 			/*
809 			 * determine hostname to use.
810 			 * force defined name if there is a valid alias
811 			 * otherwise fallback to primary hostname
812 			 */
813 			/* XXX: getaddrinfo() can't do alias check */
814 			switch(hrp->hostinfo->ai_family) {
815 			case AF_INET:
816 				addr = &((struct sockaddr_in *)hrp->hostinfo->ai_addr)->sin_addr;
817 				addrsize = sizeof(struct in_addr);
818 				break;
819 			case AF_INET6:
820 				addr = &((struct sockaddr_in6 *)hrp->hostinfo->ai_addr)->sin6_addr;
821 				addrsize = sizeof(struct in6_addr);
822 				break;
823 			default:
824 				/* should not reach here */
825 				freeaddrinfo(hrp->hostinfo);
826 				if (insert)
827 					free(hrp); /*not in chain, can free*/
828 				else
829 					hrp->hostinfo = NULL; /*mark as blank*/
830 				goto nextline;
831 				/* NOTREACHED */
832 			}
833 			if ((hp = getipnodebyaddr(addr, addrsize,
834 						  hrp->hostinfo->ai_family,
835 						  &hp_error)) != NULL) {
836 				if (strcmp(vhost, hp->h_name) != 0) {
837 					if (hp->h_aliases == NULL)
838 						vhost = hp->h_name;
839 					else {
840 						i = 0;
841 						while (hp->h_aliases[i] &&
842 						       strcmp(vhost, hp->h_aliases[i]) != 0)
843 							++i;
844 						if (hp->h_aliases[i] == NULL)
845 							vhost = hp->h_name;
846 					}
847 				}
848 			}
849 			if (hrp->hostname &&
850 			    strcmp(hrp->hostname, vhost) != 0) {
851 				free(hrp->hostname);
852 				hrp->hostname = NULL;
853 			}
854 			if (hrp->hostname == NULL &&
855 			    (hrp->hostname = strdup(vhost)) == NULL) {
856 				freeaddrinfo(hrp->hostinfo);
857 				hrp->hostinfo = NULL; /* mark as blank */
858 				if (hp)
859 					freehostent(hp);
860 				goto nextline;
861 			}
862 			hrp->anonuser = anonuser;
863 			hrp->statfile = statfile;
864 			hrp->welcome  = welcome;
865 			hrp->loginmsg = loginmsg;
866 			if (insert) {
867 				hrp->next  = NULL;
868 				lhrp->next = hrp;
869 				lhrp = hrp;
870 			}
871 			if (hp)
872 				freehostent(hp);
873 		      }
874 nextline:
875 			if (mp)
876 				free(mp);
877 		}
878 		(void) fclose(fp);
879 	}
880 }
881 
882 static void
883 selecthost(union sockunion *su)
884 {
885 	struct ftphost	*hrp;
886 	u_int16_t port;
887 #ifdef INET6
888 	struct in6_addr *mapped_in6 = NULL;
889 #endif
890 	struct addrinfo *hi;
891 
892 #ifdef INET6
893 	/*
894 	 * XXX IPv4 mapped IPv6 addr consideraton,
895 	 * specified in rfc2373.
896 	 */
897 	if (su->su_family == AF_INET6 &&
898 	    IN6_IS_ADDR_V4MAPPED(&su->su_sin6.sin6_addr))
899 		mapped_in6 = &su->su_sin6.sin6_addr;
900 #endif
901 
902 	hrp = thishost = firsthost;	/* default */
903 	port = su->su_port;
904 	su->su_port = 0;
905 	while (hrp != NULL) {
906 	    for (hi = hrp->hostinfo; hi != NULL; hi = hi->ai_next) {
907 		if (memcmp(su, hi->ai_addr, hi->ai_addrlen) == 0) {
908 			thishost = hrp;
909 			goto found;
910 		}
911 #ifdef INET6
912 		/* XXX IPv4 mapped IPv6 addr consideraton */
913 		if (hi->ai_addr->sa_family == AF_INET && mapped_in6 != NULL &&
914 		    (memcmp(&mapped_in6->s6_addr[12],
915 			    &((struct sockaddr_in *)hi->ai_addr)->sin_addr,
916 			    sizeof(struct in_addr)) == 0)) {
917 			thishost = hrp;
918 			goto found;
919 		}
920 #endif
921 	    }
922 	    hrp = hrp->next;
923 	}
924 found:
925 	su->su_port = port;
926 	/* setup static variables as appropriate */
927 	hostname = thishost->hostname;
928 	ftpuser = thishost->anonuser;
929 }
930 #endif
931 
932 /*
933  * Helper function for sgetpwnam().
934  */
935 static char *
936 sgetsave(char *s)
937 {
938 	char *new = malloc(strlen(s) + 1);
939 
940 	if (new == NULL) {
941 		reply(421, "Ran out of memory.");
942 		dologout(1);
943 		/* NOTREACHED */
944 	}
945 	(void) strcpy(new, s);
946 	return (new);
947 }
948 
949 /*
950  * Save the result of a getpwnam.  Used for USER command, since
951  * the data returned must not be clobbered by any other command
952  * (e.g., globbing).
953  * NB: The data returned by sgetpwnam() will remain valid until
954  * the next call to this function.  Its difference from getpwnam()
955  * is that sgetpwnam() is known to be called from ftpd code only.
956  */
957 static struct passwd *
958 sgetpwnam(char *name)
959 {
960 	static struct passwd save;
961 	struct passwd *p;
962 
963 	if ((p = getpwnam(name)) == NULL)
964 		return (p);
965 	if (save.pw_name) {
966 		free(save.pw_name);
967 		free(save.pw_passwd);
968 		free(save.pw_gecos);
969 		free(save.pw_dir);
970 		free(save.pw_shell);
971 	}
972 	save = *p;
973 	save.pw_name = sgetsave(p->pw_name);
974 	save.pw_passwd = sgetsave(p->pw_passwd);
975 	save.pw_gecos = sgetsave(p->pw_gecos);
976 	save.pw_dir = sgetsave(p->pw_dir);
977 	save.pw_shell = sgetsave(p->pw_shell);
978 	return (&save);
979 }
980 
981 static int login_attempts;	/* number of failed login attempts */
982 static int askpasswd;		/* had user command, ask for passwd */
983 static char curname[MAXLOGNAME];	/* current USER name */
984 
985 /*
986  * USER command.
987  * Sets global passwd pointer pw if named account exists and is acceptable;
988  * sets askpasswd if a PASS command is expected.  If logged in previously,
989  * need to reset state.  If name is "ftp" or "anonymous", the name is not in
990  * _PATH_FTPUSERS, and ftp account exists, set guest and pw, then just return.
991  * If account doesn't exist, ask for passwd anyway.  Otherwise, check user
992  * requesting login privileges.  Disallow anyone who does not have a standard
993  * shell as returned by getusershell().  Disallow anyone mentioned in the file
994  * _PATH_FTPUSERS to allow people such as root and uucp to be avoided.
995  */
996 void
997 user(char *name)
998 {
999 	int ecode;
1000 	char *cp, *shell;
1001 
1002 	if (logged_in) {
1003 		if (guest) {
1004 			reply(530, "Can't change user from guest login.");
1005 			return;
1006 		} else if (dochroot) {
1007 			reply(530, "Can't change user from chroot user.");
1008 			return;
1009 		}
1010 		end_login();
1011 	}
1012 
1013 	guest = 0;
1014 #ifdef VIRTUAL_HOSTING
1015 	pw = sgetpwnam(thishost->anonuser);
1016 #else
1017 	pw = sgetpwnam("ftp");
1018 #endif
1019 	if (strcmp(name, "ftp") == 0 || strcmp(name, "anonymous") == 0) {
1020 		if (checkuser(_PATH_FTPUSERS, "ftp", 0, NULL, &ecode) ||
1021 		    (ecode != 0 && ecode != ENOENT))
1022 			reply(530, "User %s access denied.", name);
1023 		else if (checkuser(_PATH_FTPUSERS, "anonymous", 0, NULL, &ecode) ||
1024 		    (ecode != 0 && ecode != ENOENT))
1025 			reply(530, "User %s access denied.", name);
1026 		else if (pw != NULL) {
1027 			guest = 1;
1028 			askpasswd = 1;
1029 			reply(331,
1030 			"Guest login ok, send your email address as password.");
1031 		} else
1032 			reply(530, "User %s unknown.", name);
1033 		if (!askpasswd && logging)
1034 			syslog(LOG_NOTICE,
1035 			    "ANONYMOUS FTP LOGIN REFUSED FROM %s", remotehost);
1036 		return;
1037 	}
1038 	if (anon_only != 0) {
1039 		reply(530, "Sorry, only anonymous ftp allowed.");
1040 		return;
1041 	}
1042 
1043 	if ((pw = sgetpwnam(name))) {
1044 		if ((shell = pw->pw_shell) == NULL || *shell == 0)
1045 			shell = _PATH_BSHELL;
1046 		setusershell();
1047 		while ((cp = getusershell()) != NULL)
1048 			if (strcmp(cp, shell) == 0)
1049 				break;
1050 		endusershell();
1051 
1052 		if (cp == NULL ||
1053 		    (checkuser(_PATH_FTPUSERS, name, 1, NULL, &ecode) ||
1054 		    (ecode != 0 && ecode != ENOENT))) {
1055 			reply(530, "User %s access denied.", name);
1056 			if (logging)
1057 				syslog(LOG_NOTICE,
1058 				    "FTP LOGIN REFUSED FROM %s, %s",
1059 				    remotehost, name);
1060 			pw = NULL;
1061 			return;
1062 		}
1063 	}
1064 	if (logging)
1065 		strncpy(curname, name, sizeof(curname)-1);
1066 
1067 	pwok = 0;
1068 #ifdef USE_PAM
1069 	/* XXX Kluge! The conversation mechanism needs to be fixed. */
1070 #endif
1071 	if (opiechallenge(&opiedata, name, opieprompt) == 0) {
1072 		pwok = (pw != NULL) &&
1073 		       opieaccessfile(remotehost) &&
1074 		       opiealways(pw->pw_dir);
1075 		reply(331, "Response to %s %s for %s.",
1076 		      opieprompt, pwok ? "requested" : "required", name);
1077 	} else {
1078 		pwok = 1;
1079 		reply(331, "Password required for %s.", name);
1080 	}
1081 	askpasswd = 1;
1082 	/*
1083 	 * Delay before reading passwd after first failed
1084 	 * attempt to slow down passwd-guessing programs.
1085 	 */
1086 	if (login_attempts)
1087 		sleep(login_attempts);
1088 }
1089 
1090 /*
1091  * Check if a user is in the file "fname",
1092  * return a pointer to a malloc'd string with the rest
1093  * of the matching line in "residue" if not NULL.
1094  */
1095 static int
1096 checkuser(char *fname, char *name, int pwset, char **residue, int *ecode)
1097 {
1098 	FILE *fd;
1099 	int found = 0;
1100 	size_t len;
1101 	char *line, *mp, *p;
1102 
1103 	if (ecode != NULL)
1104 		*ecode = 0;
1105 	if ((fd = fopen(fname, "r")) != NULL) {
1106 		while (!found && (line = fgetln(fd, &len)) != NULL) {
1107 			/* skip comments */
1108 			if (line[0] == '#')
1109 				continue;
1110 			if (line[len - 1] == '\n') {
1111 				line[len - 1] = '\0';
1112 				mp = NULL;
1113 			} else {
1114 				if ((mp = malloc(len + 1)) == NULL)
1115 					fatalerror("Ran out of memory.");
1116 				memcpy(mp, line, len);
1117 				mp[len] = '\0';
1118 				line = mp;
1119 			}
1120 			/* avoid possible leading and trailing whitespace */
1121 			p = strtok(line, " \t");
1122 			/* skip empty lines */
1123 			if (p == NULL)
1124 				goto nextline;
1125 			/*
1126 			 * if first chr is '@', check group membership
1127 			 */
1128 			if (p[0] == '@') {
1129 				int i = 0;
1130 				struct group *grp;
1131 
1132 				if (p[1] == '\0') /* single @ matches anyone */
1133 					found = 1;
1134 				else {
1135 					if ((grp = getgrnam(p+1)) == NULL)
1136 						goto nextline;
1137 					/*
1138 					 * Check user's default group
1139 					 */
1140 					if (pwset && grp->gr_gid == pw->pw_gid)
1141 						found = 1;
1142 					/*
1143 					 * Check supplementary groups
1144 					 */
1145 					while (!found && grp->gr_mem[i])
1146 						found = strcmp(name,
1147 							grp->gr_mem[i++])
1148 							== 0;
1149 				}
1150 			}
1151 			/*
1152 			 * Otherwise, just check for username match
1153 			 */
1154 			else
1155 				found = strcmp(p, name) == 0;
1156 			/*
1157 			 * Save the rest of line to "residue" if matched
1158 			 */
1159 			if (found && residue) {
1160 				if ((p = strtok(NULL, "")) != NULL)
1161 					p += strspn(p, " \t");
1162 				if (p && *p) {
1163 				 	if ((*residue = strdup(p)) == NULL)
1164 						fatalerror("Ran out of memory.");
1165 				} else
1166 					*residue = NULL;
1167 			}
1168 nextline:
1169 			if (mp)
1170 				free(mp);
1171 		}
1172 		(void) fclose(fd);
1173 	} else if (ecode != NULL)
1174 		*ecode = errno;
1175 	return (found);
1176 }
1177 
1178 /*
1179  * Terminate login as previous user, if any, resetting state;
1180  * used when USER command is given or login fails.
1181  */
1182 static void
1183 end_login(void)
1184 {
1185 #ifdef USE_PAM
1186 	int e;
1187 #endif
1188 
1189 	(void) seteuid(0);
1190 	if (logged_in && dowtmp)
1191 		ftpd_logwtmp(wtmpid, NULL, NULL);
1192 	pw = NULL;
1193 #ifdef	LOGIN_CAP
1194 	setusercontext(NULL, getpwuid(0), 0,
1195 		       LOGIN_SETPRIORITY|LOGIN_SETRESOURCES|LOGIN_SETUMASK|
1196 		       LOGIN_SETMAC);
1197 #endif
1198 #ifdef USE_PAM
1199 	if (pamh) {
1200 		if ((e = pam_setcred(pamh, PAM_DELETE_CRED)) != PAM_SUCCESS)
1201 			syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, e));
1202 		if ((e = pam_close_session(pamh,0)) != PAM_SUCCESS)
1203 			syslog(LOG_ERR, "pam_close_session: %s", pam_strerror(pamh, e));
1204 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS)
1205 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1206 		pamh = NULL;
1207 	}
1208 #endif
1209 	logged_in = 0;
1210 	guest = 0;
1211 	dochroot = 0;
1212 }
1213 
1214 #ifdef USE_PAM
1215 
1216 /*
1217  * the following code is stolen from imap-uw PAM authentication module and
1218  * login.c
1219  */
1220 #define COPY_STRING(s) (s ? strdup(s) : NULL)
1221 
1222 struct cred_t {
1223 	const char *uname;		/* user name */
1224 	const char *pass;		/* password */
1225 };
1226 typedef struct cred_t cred_t;
1227 
1228 static int
1229 auth_conv(int num_msg, const struct pam_message **msg,
1230 	  struct pam_response **resp, void *appdata)
1231 {
1232 	int i;
1233 	cred_t *cred = (cred_t *) appdata;
1234 	struct pam_response *reply;
1235 
1236 	reply = calloc(num_msg, sizeof *reply);
1237 	if (reply == NULL)
1238 		return PAM_BUF_ERR;
1239 
1240 	for (i = 0; i < num_msg; i++) {
1241 		switch (msg[i]->msg_style) {
1242 		case PAM_PROMPT_ECHO_ON:	/* assume want user name */
1243 			reply[i].resp_retcode = PAM_SUCCESS;
1244 			reply[i].resp = COPY_STRING(cred->uname);
1245 			/* PAM frees resp. */
1246 			break;
1247 		case PAM_PROMPT_ECHO_OFF:	/* assume want password */
1248 			reply[i].resp_retcode = PAM_SUCCESS;
1249 			reply[i].resp = COPY_STRING(cred->pass);
1250 			/* PAM frees resp. */
1251 			break;
1252 		case PAM_TEXT_INFO:
1253 		case PAM_ERROR_MSG:
1254 			reply[i].resp_retcode = PAM_SUCCESS;
1255 			reply[i].resp = NULL;
1256 			break;
1257 		default:			/* unknown message style */
1258 			free(reply);
1259 			return PAM_CONV_ERR;
1260 		}
1261 	}
1262 
1263 	*resp = reply;
1264 	return PAM_SUCCESS;
1265 }
1266 
1267 /*
1268  * Attempt to authenticate the user using PAM.  Returns 0 if the user is
1269  * authenticated, or 1 if not authenticated.  If some sort of PAM system
1270  * error occurs (e.g., the "/etc/pam.conf" file is missing) then this
1271  * function returns -1.  This can be used as an indication that we should
1272  * fall back to a different authentication mechanism.
1273  */
1274 static int
1275 auth_pam(struct passwd **ppw, const char *pass)
1276 {
1277 	const char *tmpl_user;
1278 	const void *item;
1279 	int rval;
1280 	int e;
1281 	cred_t auth_cred = { (*ppw)->pw_name, pass };
1282 	struct pam_conv conv = { &auth_conv, &auth_cred };
1283 
1284 	e = pam_start("ftpd", (*ppw)->pw_name, &conv, &pamh);
1285 	if (e != PAM_SUCCESS) {
1286 		/*
1287 		 * In OpenPAM, it's OK to pass NULL to pam_strerror()
1288 		 * if context creation has failed in the first place.
1289 		 */
1290 		syslog(LOG_ERR, "pam_start: %s", pam_strerror(NULL, e));
1291 		return -1;
1292 	}
1293 
1294 	e = pam_set_item(pamh, PAM_RHOST, remotehost);
1295 	if (e != PAM_SUCCESS) {
1296 		syslog(LOG_ERR, "pam_set_item(PAM_RHOST): %s",
1297 			pam_strerror(pamh, e));
1298 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
1299 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1300 		}
1301 		pamh = NULL;
1302 		return -1;
1303 	}
1304 
1305 	e = pam_authenticate(pamh, 0);
1306 	switch (e) {
1307 	case PAM_SUCCESS:
1308 		/*
1309 		 * With PAM we support the concept of a "template"
1310 		 * user.  The user enters a login name which is
1311 		 * authenticated by PAM, usually via a remote service
1312 		 * such as RADIUS or TACACS+.  If authentication
1313 		 * succeeds, a different but related "template" name
1314 		 * is used for setting the credentials, shell, and
1315 		 * home directory.  The name the user enters need only
1316 		 * exist on the remote authentication server, but the
1317 		 * template name must be present in the local password
1318 		 * database.
1319 		 *
1320 		 * This is supported by two various mechanisms in the
1321 		 * individual modules.  However, from the application's
1322 		 * point of view, the template user is always passed
1323 		 * back as a changed value of the PAM_USER item.
1324 		 */
1325 		if ((e = pam_get_item(pamh, PAM_USER, &item)) ==
1326 		    PAM_SUCCESS) {
1327 			tmpl_user = (const char *) item;
1328 			if (strcmp((*ppw)->pw_name, tmpl_user) != 0)
1329 				*ppw = getpwnam(tmpl_user);
1330 		} else
1331 			syslog(LOG_ERR, "Couldn't get PAM_USER: %s",
1332 			    pam_strerror(pamh, e));
1333 		rval = 0;
1334 		break;
1335 
1336 	case PAM_AUTH_ERR:
1337 	case PAM_USER_UNKNOWN:
1338 	case PAM_MAXTRIES:
1339 		rval = 1;
1340 		break;
1341 
1342 	default:
1343 		syslog(LOG_ERR, "pam_authenticate: %s", pam_strerror(pamh, e));
1344 		rval = -1;
1345 		break;
1346 	}
1347 
1348 	if (rval == 0) {
1349 		e = pam_acct_mgmt(pamh, 0);
1350 		if (e != PAM_SUCCESS) {
1351 			syslog(LOG_ERR, "pam_acct_mgmt: %s",
1352 						pam_strerror(pamh, e));
1353 			rval = 1;
1354 		}
1355 	}
1356 
1357 	if (rval != 0) {
1358 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
1359 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1360 		}
1361 		pamh = NULL;
1362 	}
1363 	return rval;
1364 }
1365 
1366 #endif /* USE_PAM */
1367 
1368 void
1369 pass(char *passwd)
1370 {
1371 	int rval, ecode;
1372 	FILE *fd;
1373 #ifdef	LOGIN_CAP
1374 	login_cap_t *lc = NULL;
1375 #endif
1376 #ifdef USE_PAM
1377 	int e;
1378 #endif
1379 	char *residue = NULL;
1380 	char *xpasswd;
1381 
1382 	if (logged_in || askpasswd == 0) {
1383 		reply(503, "Login with USER first.");
1384 		return;
1385 	}
1386 	askpasswd = 0;
1387 	if (!guest) {		/* "ftp" is only account allowed no password */
1388 		if (pw == NULL) {
1389 			rval = 1;	/* failure below */
1390 			goto skip;
1391 		}
1392 #ifdef USE_PAM
1393 		rval = auth_pam(&pw, passwd);
1394 		if (rval >= 0) {
1395 			opieunlock();
1396 			goto skip;
1397 		}
1398 #endif
1399 		if (opieverify(&opiedata, passwd) == 0)
1400 			xpasswd = pw->pw_passwd;
1401 		else if (pwok) {
1402 			xpasswd = crypt(passwd, pw->pw_passwd);
1403 			if (passwd[0] == '\0' && pw->pw_passwd[0] != '\0')
1404 				xpasswd = ":";
1405 		} else {
1406 			rval = 1;
1407 			goto skip;
1408 		}
1409 		rval = strcmp(pw->pw_passwd, xpasswd);
1410 		if (pw->pw_expire && time(NULL) >= pw->pw_expire)
1411 			rval = 1;	/* failure */
1412 skip:
1413 		/*
1414 		 * If rval == 1, the user failed the authentication check
1415 		 * above.  If rval == 0, either PAM or local authentication
1416 		 * succeeded.
1417 		 */
1418 		if (rval) {
1419 			reply(530, "Login incorrect.");
1420 			if (logging) {
1421 				syslog(LOG_NOTICE,
1422 				    "FTP LOGIN FAILED FROM %s",
1423 				    remotehost);
1424 				syslog(LOG_AUTHPRIV | LOG_NOTICE,
1425 				    "FTP LOGIN FAILED FROM %s, %s",
1426 				    remotehost, curname);
1427 			}
1428 			pw = NULL;
1429 			if (login_attempts++ >= 5) {
1430 				syslog(LOG_NOTICE,
1431 				    "repeated login failures from %s",
1432 				    remotehost);
1433 				exit(0);
1434 			}
1435 			return;
1436 		}
1437 	}
1438 	login_attempts = 0;		/* this time successful */
1439 	if (setegid(pw->pw_gid) < 0) {
1440 		reply(550, "Can't set gid.");
1441 		return;
1442 	}
1443 	/* May be overridden by login.conf */
1444 	(void) umask(defumask);
1445 #ifdef	LOGIN_CAP
1446 	if ((lc = login_getpwclass(pw)) != NULL) {
1447 		char	remote_ip[NI_MAXHOST];
1448 
1449 		if (getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
1450 			remote_ip, sizeof(remote_ip) - 1, NULL, 0,
1451 			NI_NUMERICHOST))
1452 				*remote_ip = 0;
1453 		remote_ip[sizeof(remote_ip) - 1] = 0;
1454 		if (!auth_hostok(lc, remotehost, remote_ip)) {
1455 			syslog(LOG_INFO|LOG_AUTH,
1456 			    "FTP LOGIN FAILED (HOST) as %s: permission denied.",
1457 			    pw->pw_name);
1458 			reply(530, "Permission denied.");
1459 			pw = NULL;
1460 			return;
1461 		}
1462 		if (!auth_timeok(lc, time(NULL))) {
1463 			reply(530, "Login not available right now.");
1464 			pw = NULL;
1465 			return;
1466 		}
1467 	}
1468 	setusercontext(lc, pw, 0,
1469 		LOGIN_SETLOGIN|LOGIN_SETGROUP|LOGIN_SETPRIORITY|
1470 		LOGIN_SETRESOURCES|LOGIN_SETUMASK|LOGIN_SETMAC);
1471 #else
1472 	setlogin(pw->pw_name);
1473 	(void) initgroups(pw->pw_name, pw->pw_gid);
1474 #endif
1475 
1476 #ifdef USE_PAM
1477 	if (pamh) {
1478 		if ((e = pam_open_session(pamh, 0)) != PAM_SUCCESS) {
1479 			syslog(LOG_ERR, "pam_open_session: %s", pam_strerror(pamh, e));
1480 		} else if ((e = pam_setcred(pamh, PAM_ESTABLISH_CRED)) != PAM_SUCCESS) {
1481 			syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, e));
1482 		}
1483 	}
1484 #endif
1485 
1486 	dochroot =
1487 		checkuser(_PATH_FTPCHROOT, pw->pw_name, 1, &residue, &ecode)
1488 #ifdef	LOGIN_CAP	/* Allow login.conf configuration as well */
1489 		|| login_getcapbool(lc, "ftp-chroot", 0)
1490 #endif
1491 	;
1492 	/*
1493 	 * It is possible that checkuser() failed to open the chroot file.
1494 	 * If this is the case, report that logins are un-available, since we
1495 	 * have no way of checking whether or not the user should be chrooted.
1496 	 * We ignore ENOENT since it is not required that this file be present.
1497 	 */
1498 	if (ecode != 0 && ecode != ENOENT) {
1499 		reply(530, "Login not available right now.");
1500 		return;
1501 	}
1502 	chrootdir = NULL;
1503 
1504 	/* Disable wtmp logging when chrooting. */
1505 	if (dochroot || guest)
1506 		dowtmp = 0;
1507 	if (dowtmp)
1508 		ftpd_logwtmp(wtmpid, pw->pw_name,
1509 		    (struct sockaddr *)&his_addr);
1510 	logged_in = 1;
1511 
1512 	if (guest && stats && statfd < 0)
1513 #ifdef VIRTUAL_HOSTING
1514 		statfd = open(thishost->statfile, O_WRONLY|O_APPEND);
1515 #else
1516 		statfd = open(_PATH_FTPDSTATFILE, O_WRONLY|O_APPEND);
1517 #endif
1518 		if (statfd < 0)
1519 			stats = 0;
1520 
1521 	/*
1522 	 * For a chrooted local user,
1523 	 * a) see whether ftpchroot(5) specifies a chroot directory,
1524 	 * b) extract the directory pathname from the line,
1525 	 * c) expand it to the absolute pathname if necessary.
1526 	 */
1527 	if (dochroot && residue &&
1528 	    (chrootdir = strtok(residue, " \t")) != NULL) {
1529 		if (chrootdir[0] != '/')
1530 			asprintf(&chrootdir, "%s/%s", pw->pw_dir, chrootdir);
1531 		else
1532 			chrootdir = strdup(chrootdir); /* make it permanent */
1533 		if (chrootdir == NULL)
1534 			fatalerror("Ran out of memory.");
1535 	}
1536 	if (guest || dochroot) {
1537 		/*
1538 		 * If no chroot directory set yet, use the login directory.
1539 		 * Copy it so it can be modified while pw->pw_dir stays intact.
1540 		 */
1541 		if (chrootdir == NULL &&
1542 		    (chrootdir = strdup(pw->pw_dir)) == NULL)
1543 			fatalerror("Ran out of memory.");
1544 		/*
1545 		 * Check for the "/chroot/./home" syntax,
1546 		 * separate the chroot and home directory pathnames.
1547 		 */
1548 		if ((homedir = strstr(chrootdir, "/./")) != NULL) {
1549 			*(homedir++) = '\0';	/* wipe '/' */
1550 			homedir++;		/* skip '.' */
1551 		} else {
1552 			/*
1553 			 * We MUST do a chdir() after the chroot. Otherwise
1554 			 * the old current directory will be accessible as "."
1555 			 * outside the new root!
1556 			 */
1557 			homedir = "/";
1558 		}
1559 		/*
1560 		 * Finally, do chroot()
1561 		 */
1562 		if (chroot(chrootdir) < 0) {
1563 			reply(550, "Can't change root.");
1564 			goto bad;
1565 		}
1566 	} else	/* real user w/o chroot */
1567 		homedir = pw->pw_dir;
1568 	/*
1569 	 * Set euid *before* doing chdir() so
1570 	 * a) the user won't be carried to a directory that he couldn't reach
1571 	 *    on his own due to no permission to upper path components,
1572 	 * b) NFS mounted homedirs w/restrictive permissions will be accessible
1573 	 *    (uid 0 has no root power over NFS if not mapped explicitly.)
1574 	 */
1575 	if (seteuid(pw->pw_uid) < 0) {
1576 		reply(550, "Can't set uid.");
1577 		goto bad;
1578 	}
1579 	if (chdir(homedir) < 0) {
1580 		if (guest || dochroot) {
1581 			reply(550, "Can't change to base directory.");
1582 			goto bad;
1583 		} else {
1584 			if (chdir("/") < 0) {
1585 				reply(550, "Root is inaccessible.");
1586 				goto bad;
1587 			}
1588 			lreply(230, "No directory! Logging in with home=/.");
1589 		}
1590 	}
1591 
1592 	/*
1593 	 * Display a login message, if it exists.
1594 	 * N.B. reply(230,) must follow the message.
1595 	 */
1596 #ifdef VIRTUAL_HOSTING
1597 	fd = fopen(thishost->loginmsg, "r");
1598 #else
1599 	fd = fopen(_PATH_FTPLOGINMESG, "r");
1600 #endif
1601 	if (fd != NULL) {
1602 		char *cp, line[LINE_MAX];
1603 
1604 		while (fgets(line, sizeof(line), fd) != NULL) {
1605 			if ((cp = strchr(line, '\n')) != NULL)
1606 				*cp = '\0';
1607 			lreply(230, "%s", line);
1608 		}
1609 		(void) fflush(stdout);
1610 		(void) fclose(fd);
1611 	}
1612 	if (guest) {
1613 		if (ident != NULL)
1614 			free(ident);
1615 		ident = strdup(passwd);
1616 		if (ident == NULL)
1617 			fatalerror("Ran out of memory.");
1618 
1619 		reply(230, "Guest login ok, access restrictions apply.");
1620 #ifdef SETPROCTITLE
1621 #ifdef VIRTUAL_HOSTING
1622 		if (thishost != firsthost)
1623 			snprintf(proctitle, sizeof(proctitle),
1624 				 "%s: anonymous(%s)/%s", remotehost, hostname,
1625 				 passwd);
1626 		else
1627 #endif
1628 			snprintf(proctitle, sizeof(proctitle),
1629 				 "%s: anonymous/%s", remotehost, passwd);
1630 		setproctitle("%s", proctitle);
1631 #endif /* SETPROCTITLE */
1632 		if (logging)
1633 			syslog(LOG_INFO, "ANONYMOUS FTP LOGIN FROM %s, %s",
1634 			    remotehost, passwd);
1635 	} else {
1636 		if (dochroot)
1637 			reply(230, "User %s logged in, "
1638 				   "access restrictions apply.", pw->pw_name);
1639 		else
1640 			reply(230, "User %s logged in.", pw->pw_name);
1641 
1642 #ifdef SETPROCTITLE
1643 		snprintf(proctitle, sizeof(proctitle),
1644 			 "%s: user/%s", remotehost, pw->pw_name);
1645 		setproctitle("%s", proctitle);
1646 #endif /* SETPROCTITLE */
1647 		if (logging)
1648 			syslog(LOG_INFO, "FTP LOGIN FROM %s as %s",
1649 			    remotehost, pw->pw_name);
1650 	}
1651 	if (logging && (guest || dochroot))
1652 		syslog(LOG_INFO, "session root changed to %s", chrootdir);
1653 #ifdef	LOGIN_CAP
1654 	login_close(lc);
1655 #endif
1656 	if (residue)
1657 		free(residue);
1658 	return;
1659 bad:
1660 	/* Forget all about it... */
1661 #ifdef	LOGIN_CAP
1662 	login_close(lc);
1663 #endif
1664 	if (residue)
1665 		free(residue);
1666 	end_login();
1667 }
1668 
1669 void
1670 retrieve(char *cmd, char *name)
1671 {
1672 	FILE *fin, *dout;
1673 	struct stat st;
1674 	int (*closefunc)(FILE *);
1675 	time_t start;
1676 
1677 	if (cmd == 0) {
1678 		fin = fopen(name, "r"), closefunc = fclose;
1679 		st.st_size = 0;
1680 	} else {
1681 		char line[BUFSIZ];
1682 
1683 		(void) snprintf(line, sizeof(line), cmd, name), name = line;
1684 		fin = ftpd_popen(line, "r"), closefunc = ftpd_pclose;
1685 		st.st_size = -1;
1686 		st.st_blksize = BUFSIZ;
1687 	}
1688 	if (fin == NULL) {
1689 		if (errno != 0) {
1690 			perror_reply(550, name);
1691 			if (cmd == 0) {
1692 				LOGCMD("get", name);
1693 			}
1694 		}
1695 		return;
1696 	}
1697 	byte_count = -1;
1698 	if (cmd == 0) {
1699 		if (fstat(fileno(fin), &st) < 0) {
1700 			perror_reply(550, name);
1701 			goto done;
1702 		}
1703 		if (!S_ISREG(st.st_mode)) {
1704 			/*
1705 			 * Never sending a raw directory is a workaround
1706 			 * for buggy clients that will attempt to RETR
1707 			 * a directory before listing it, e.g., Mozilla.
1708 			 * Preventing a guest from getting irregular files
1709 			 * is a simple security measure.
1710 			 */
1711 			if (S_ISDIR(st.st_mode) || guest) {
1712 				reply(550, "%s: not a plain file.", name);
1713 				goto done;
1714 			}
1715 			st.st_size = -1;
1716 			/* st.st_blksize is set for all descriptor types */
1717 		}
1718 	}
1719 	if (restart_point) {
1720 		if (type == TYPE_A) {
1721 			off_t i, n;
1722 			int c;
1723 
1724 			n = restart_point;
1725 			i = 0;
1726 			while (i++ < n) {
1727 				if ((c=getc(fin)) == EOF) {
1728 					perror_reply(550, name);
1729 					goto done;
1730 				}
1731 				if (c == '\n')
1732 					i++;
1733 			}
1734 		} else if (lseek(fileno(fin), restart_point, L_SET) < 0) {
1735 			perror_reply(550, name);
1736 			goto done;
1737 		}
1738 	}
1739 	dout = dataconn(name, st.st_size, "w");
1740 	if (dout == NULL)
1741 		goto done;
1742 	time(&start);
1743 	send_data(fin, dout, st.st_blksize, st.st_size,
1744 		  restart_point == 0 && cmd == 0 && S_ISREG(st.st_mode));
1745 	if (cmd == 0 && guest && stats && byte_count > 0)
1746 		logxfer(name, byte_count, start);
1747 	(void) fclose(dout);
1748 	data = -1;
1749 	pdata = -1;
1750 done:
1751 	if (cmd == 0)
1752 		LOGBYTES("get", name, byte_count);
1753 	(*closefunc)(fin);
1754 }
1755 
1756 void
1757 store(char *name, char *mode, int unique)
1758 {
1759 	int fd;
1760 	FILE *fout, *din;
1761 	int (*closefunc)(FILE *);
1762 
1763 	if (*mode == 'a') {		/* APPE */
1764 		if (unique) {
1765 			/* Programming error */
1766 			syslog(LOG_ERR, "Internal: unique flag to APPE");
1767 			unique = 0;
1768 		}
1769 		if (guest && noguestmod) {
1770 			reply(550, "Appending to existing file denied.");
1771 			goto err;
1772 		}
1773 		restart_point = 0;	/* not affected by preceding REST */
1774 	}
1775 	if (unique)			/* STOU overrides REST */
1776 		restart_point = 0;
1777 	if (guest && noguestmod) {
1778 		if (restart_point) {	/* guest STOR w/REST */
1779 			reply(550, "Modifying existing file denied.");
1780 			goto err;
1781 		} else			/* treat guest STOR as STOU */
1782 			unique = 1;
1783 	}
1784 
1785 	if (restart_point)
1786 		mode = "r+";	/* so ASCII manual seek can work */
1787 	if (unique) {
1788 		if ((fd = guniquefd(name, &name)) < 0)
1789 			goto err;
1790 		fout = fdopen(fd, mode);
1791 	} else
1792 		fout = fopen(name, mode);
1793 	closefunc = fclose;
1794 	if (fout == NULL) {
1795 		perror_reply(553, name);
1796 		goto err;
1797 	}
1798 	byte_count = -1;
1799 	if (restart_point) {
1800 		if (type == TYPE_A) {
1801 			off_t i, n;
1802 			int c;
1803 
1804 			n = restart_point;
1805 			i = 0;
1806 			while (i++ < n) {
1807 				if ((c=getc(fout)) == EOF) {
1808 					perror_reply(550, name);
1809 					goto done;
1810 				}
1811 				if (c == '\n')
1812 					i++;
1813 			}
1814 			/*
1815 			 * We must do this seek to "current" position
1816 			 * because we are changing from reading to
1817 			 * writing.
1818 			 */
1819 			if (fseeko(fout, 0, SEEK_CUR) < 0) {
1820 				perror_reply(550, name);
1821 				goto done;
1822 			}
1823 		} else if (lseek(fileno(fout), restart_point, L_SET) < 0) {
1824 			perror_reply(550, name);
1825 			goto done;
1826 		}
1827 	}
1828 	din = dataconn(name, -1, "r");
1829 	if (din == NULL)
1830 		goto done;
1831 	if (receive_data(din, fout) == 0) {
1832 		if (unique)
1833 			reply(226, "Transfer complete (unique file name:%s).",
1834 			    name);
1835 		else
1836 			reply(226, "Transfer complete.");
1837 	}
1838 	(void) fclose(din);
1839 	data = -1;
1840 	pdata = -1;
1841 done:
1842 	LOGBYTES(*mode == 'a' ? "append" : "put", name, byte_count);
1843 	(*closefunc)(fout);
1844 	return;
1845 err:
1846 	LOGCMD(*mode == 'a' ? "append" : "put" , name);
1847 	return;
1848 }
1849 
1850 static FILE *
1851 getdatasock(char *mode)
1852 {
1853 	int on = 1, s, t, tries;
1854 
1855 	if (data >= 0)
1856 		return (fdopen(data, mode));
1857 
1858 	s = socket(data_dest.su_family, SOCK_STREAM, 0);
1859 	if (s < 0)
1860 		goto bad;
1861 	if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
1862 		syslog(LOG_WARNING, "data setsockopt (SO_REUSEADDR): %m");
1863 	/* anchor socket to avoid multi-homing problems */
1864 	data_source = ctrl_addr;
1865 	data_source.su_port = htons(dataport);
1866 	(void) seteuid(0);
1867 	for (tries = 1; ; tries++) {
1868 		/*
1869 		 * We should loop here since it's possible that
1870 		 * another ftpd instance has passed this point and is
1871 		 * trying to open a data connection in active mode now.
1872 		 * Until the other connection is opened, we'll be getting
1873 		 * EADDRINUSE because no SOCK_STREAM sockets in the system
1874 		 * can share both local and remote addresses, localIP:20
1875 		 * and *:* in this case.
1876 		 */
1877 		if (bind(s, (struct sockaddr *)&data_source,
1878 		    data_source.su_len) >= 0)
1879 			break;
1880 		if (errno != EADDRINUSE || tries > 10)
1881 			goto bad;
1882 		sleep(tries);
1883 	}
1884 	(void) seteuid(pw->pw_uid);
1885 #ifdef IP_TOS
1886 	if (data_source.su_family == AF_INET)
1887       {
1888 	on = IPTOS_THROUGHPUT;
1889 	if (setsockopt(s, IPPROTO_IP, IP_TOS, &on, sizeof(int)) < 0)
1890 		syslog(LOG_WARNING, "data setsockopt (IP_TOS): %m");
1891       }
1892 #endif
1893 #ifdef TCP_NOPUSH
1894 	/*
1895 	 * Turn off push flag to keep sender TCP from sending short packets
1896 	 * at the boundaries of each write().
1897 	 */
1898 	on = 1;
1899 	if (setsockopt(s, IPPROTO_TCP, TCP_NOPUSH, &on, sizeof on) < 0)
1900 		syslog(LOG_WARNING, "data setsockopt (TCP_NOPUSH): %m");
1901 #endif
1902 	return (fdopen(s, mode));
1903 bad:
1904 	/* Return the real value of errno (close may change it) */
1905 	t = errno;
1906 	(void) seteuid(pw->pw_uid);
1907 	(void) close(s);
1908 	errno = t;
1909 	return (NULL);
1910 }
1911 
1912 static FILE *
1913 dataconn(char *name, off_t size, char *mode)
1914 {
1915 	char sizebuf[32];
1916 	FILE *file;
1917 	int retry = 0, tos, conerrno;
1918 
1919 	file_size = size;
1920 	byte_count = 0;
1921 	if (size != -1)
1922 		(void) snprintf(sizebuf, sizeof(sizebuf),
1923 				" (%jd bytes)", (intmax_t)size);
1924 	else
1925 		*sizebuf = '\0';
1926 	if (pdata >= 0) {
1927 		union sockunion from;
1928 		socklen_t fromlen = ctrl_addr.su_len;
1929 		int flags, s;
1930 		struct timeval timeout;
1931 		fd_set set;
1932 
1933 		FD_ZERO(&set);
1934 		FD_SET(pdata, &set);
1935 
1936 		timeout.tv_usec = 0;
1937 		timeout.tv_sec = 120;
1938 
1939 		/*
1940 		 * Granted a socket is in the blocking I/O mode,
1941 		 * accept() will block after a successful select()
1942 		 * if the selected connection dies in between.
1943 		 * Therefore set the non-blocking I/O flag here.
1944 		 */
1945 		if ((flags = fcntl(pdata, F_GETFL, 0)) == -1 ||
1946 		    fcntl(pdata, F_SETFL, flags | O_NONBLOCK) == -1)
1947 			goto pdata_err;
1948 		if (select(pdata+1, &set, NULL, NULL, &timeout) <= 0 ||
1949 		    (s = accept(pdata, (struct sockaddr *) &from, &fromlen)) < 0)
1950 			goto pdata_err;
1951 		(void) close(pdata);
1952 		pdata = s;
1953 		/*
1954 		 * Unset the inherited non-blocking I/O flag
1955 		 * on the child socket so stdio can work on it.
1956 		 */
1957 		if ((flags = fcntl(pdata, F_GETFL, 0)) == -1 ||
1958 		    fcntl(pdata, F_SETFL, flags & ~O_NONBLOCK) == -1)
1959 			goto pdata_err;
1960 #ifdef IP_TOS
1961 		if (from.su_family == AF_INET)
1962 	      {
1963 		tos = IPTOS_THROUGHPUT;
1964 		if (setsockopt(s, IPPROTO_IP, IP_TOS, &tos, sizeof(int)) < 0)
1965 			syslog(LOG_WARNING, "pdata setsockopt (IP_TOS): %m");
1966 	      }
1967 #endif
1968 		reply(150, "Opening %s mode data connection for '%s'%s.",
1969 		     type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
1970 		return (fdopen(pdata, mode));
1971 pdata_err:
1972 		reply(425, "Can't open data connection.");
1973 		(void) close(pdata);
1974 		pdata = -1;
1975 		return (NULL);
1976 	}
1977 	if (data >= 0) {
1978 		reply(125, "Using existing data connection for '%s'%s.",
1979 		    name, sizebuf);
1980 		usedefault = 1;
1981 		return (fdopen(data, mode));
1982 	}
1983 	if (usedefault)
1984 		data_dest = his_addr;
1985 	usedefault = 1;
1986 	do {
1987 		file = getdatasock(mode);
1988 		if (file == NULL) {
1989 			char hostbuf[NI_MAXHOST], portbuf[NI_MAXSERV];
1990 
1991 			if (getnameinfo((struct sockaddr *)&data_source,
1992 				data_source.su_len,
1993 				hostbuf, sizeof(hostbuf) - 1,
1994 				portbuf, sizeof(portbuf) - 1,
1995 				NI_NUMERICHOST|NI_NUMERICSERV))
1996 					*hostbuf = *portbuf = 0;
1997 			hostbuf[sizeof(hostbuf) - 1] = 0;
1998 			portbuf[sizeof(portbuf) - 1] = 0;
1999 			reply(425, "Can't create data socket (%s,%s): %s.",
2000 				hostbuf, portbuf, strerror(errno));
2001 			return (NULL);
2002 		}
2003 		data = fileno(file);
2004 		conerrno = 0;
2005 		if (connect(data, (struct sockaddr *)&data_dest,
2006 		    data_dest.su_len) == 0)
2007 			break;
2008 		conerrno = errno;
2009 		(void) fclose(file);
2010 		data = -1;
2011 		if (conerrno == EADDRINUSE) {
2012 			sleep(swaitint);
2013 			retry += swaitint;
2014 		} else {
2015 			break;
2016 		}
2017 	} while (retry <= swaitmax);
2018 	if (conerrno != 0) {
2019 		reply(425, "Can't build data connection: %s.",
2020 			   strerror(conerrno));
2021 		return (NULL);
2022 	}
2023 	reply(150, "Opening %s mode data connection for '%s'%s.",
2024 	     type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
2025 	return (file);
2026 }
2027 
2028 /*
2029  * A helper macro to avoid code duplication
2030  * in send_data() and receive_data().
2031  *
2032  * XXX We have to block SIGURG during putc() because BSD stdio
2033  * is unable to restart interrupted write operations and hence
2034  * the entire buffer contents will be lost as soon as a write()
2035  * call indicates EINTR to stdio.
2036  */
2037 #define FTPD_PUTC(ch, file, label)					\
2038 	do {								\
2039 		int ret;						\
2040 									\
2041 		do {							\
2042 			START_UNSAFE;					\
2043 			ret = putc((ch), (file));			\
2044 			END_UNSAFE;					\
2045 			CHECKOOB(return (-1))				\
2046 			else if (ferror(file))				\
2047 				goto label;				\
2048 			clearerr(file);					\
2049 		} while (ret == EOF);					\
2050 	} while (0)
2051 
2052 /*
2053  * Tranfer the contents of "instr" to "outstr" peer using the appropriate
2054  * encapsulation of the data subject to Mode, Structure, and Type.
2055  *
2056  * NB: Form isn't handled.
2057  */
2058 static int
2059 send_data(FILE *instr, FILE *outstr, size_t blksize, off_t filesize, int isreg)
2060 {
2061 	int c, cp, filefd, netfd;
2062 	char *buf;
2063 
2064 	STARTXFER;
2065 
2066 	switch (type) {
2067 
2068 	case TYPE_A:
2069 		cp = EOF;
2070 		for (;;) {
2071 			c = getc(instr);
2072 			CHECKOOB(return (-1))
2073 			else if (c == EOF && ferror(instr))
2074 				goto file_err;
2075 			if (c == EOF) {
2076 				if (ferror(instr)) {	/* resume after OOB */
2077 					clearerr(instr);
2078 					continue;
2079 				}
2080 				if (feof(instr))	/* EOF */
2081 					break;
2082 				syslog(LOG_ERR, "Internal: impossible condition"
2083 						" on file after getc()");
2084 				goto file_err;
2085 			}
2086 			if (c == '\n' && cp != '\r') {
2087 				FTPD_PUTC('\r', outstr, data_err);
2088 				byte_count++;
2089 			}
2090 			FTPD_PUTC(c, outstr, data_err);
2091 			byte_count++;
2092 			cp = c;
2093 		}
2094 #ifdef notyet	/* BSD stdio isn't ready for that */
2095 		while (fflush(outstr) == EOF) {
2096 			CHECKOOB(return (-1))
2097 			else
2098 				goto data_err;
2099 			clearerr(outstr);
2100 		}
2101 		ENDXFER;
2102 #else
2103 		ENDXFER;
2104 		if (fflush(outstr) == EOF)
2105 			goto data_err;
2106 #endif
2107 		reply(226, "Transfer complete.");
2108 		return (0);
2109 
2110 	case TYPE_I:
2111 	case TYPE_L:
2112 		/*
2113 		 * isreg is only set if we are not doing restart and we
2114 		 * are sending a regular file
2115 		 */
2116 		netfd = fileno(outstr);
2117 		filefd = fileno(instr);
2118 
2119 		if (isreg) {
2120 			char *msg = "Transfer complete.";
2121 			off_t cnt, offset;
2122 			int err;
2123 
2124 			cnt = offset = 0;
2125 
2126 			while (filesize > 0) {
2127 				err = sendfile(filefd, netfd, offset, 0,
2128 					       NULL, &cnt, 0);
2129 				/*
2130 				 * Calculate byte_count before OOB processing.
2131 				 * It can be used in myoob() later.
2132 				 */
2133 				byte_count += cnt;
2134 				offset += cnt;
2135 				filesize -= cnt;
2136 				CHECKOOB(return (-1))
2137 				else if (err == -1) {
2138 					if (errno != EINTR &&
2139 					    cnt == 0 && offset == 0)
2140 						goto oldway;
2141 					goto data_err;
2142 				}
2143 				if (err == -1)	/* resume after OOB */
2144 					continue;
2145 				/*
2146 				 * We hit the EOF prematurely.
2147 				 * Perhaps the file was externally truncated.
2148 				 */
2149 				if (cnt == 0) {
2150 					msg = "Transfer finished due to "
2151 					      "premature end of file.";
2152 					break;
2153 				}
2154 			}
2155 			ENDXFER;
2156 			reply(226, "%s", msg);
2157 			return (0);
2158 		}
2159 
2160 oldway:
2161 		if ((buf = malloc(blksize)) == NULL) {
2162 			ENDXFER;
2163 			reply(451, "Ran out of memory.");
2164 			return (-1);
2165 		}
2166 
2167 		for (;;) {
2168 			int cnt, len;
2169 			char *bp;
2170 
2171 			cnt = read(filefd, buf, blksize);
2172 			CHECKOOB(free(buf); return (-1))
2173 			else if (cnt < 0) {
2174 				free(buf);
2175 				goto file_err;
2176 			}
2177 			if (cnt < 0)	/* resume after OOB */
2178 				continue;
2179 			if (cnt == 0)	/* EOF */
2180 				break;
2181 			for (len = cnt, bp = buf; len > 0;) {
2182 				cnt = write(netfd, bp, len);
2183 				CHECKOOB(free(buf); return (-1))
2184 				else if (cnt < 0) {
2185 					free(buf);
2186 					goto data_err;
2187 				}
2188 				if (cnt <= 0)
2189 					continue;
2190 				len -= cnt;
2191 				bp += cnt;
2192 				byte_count += cnt;
2193 			}
2194 		}
2195 		ENDXFER;
2196 		free(buf);
2197 		reply(226, "Transfer complete.");
2198 		return (0);
2199 	default:
2200 		ENDXFER;
2201 		reply(550, "Unimplemented TYPE %d in send_data.", type);
2202 		return (-1);
2203 	}
2204 
2205 data_err:
2206 	ENDXFER;
2207 	perror_reply(426, "Data connection");
2208 	return (-1);
2209 
2210 file_err:
2211 	ENDXFER;
2212 	perror_reply(551, "Error on input file");
2213 	return (-1);
2214 }
2215 
2216 /*
2217  * Transfer data from peer to "outstr" using the appropriate encapulation of
2218  * the data subject to Mode, Structure, and Type.
2219  *
2220  * N.B.: Form isn't handled.
2221  */
2222 static int
2223 receive_data(FILE *instr, FILE *outstr)
2224 {
2225 	int c, cp;
2226 	int bare_lfs = 0;
2227 
2228 	STARTXFER;
2229 
2230 	switch (type) {
2231 
2232 	case TYPE_I:
2233 	case TYPE_L:
2234 		for (;;) {
2235 			int cnt, len;
2236 			char *bp;
2237 			char buf[BUFSIZ];
2238 
2239 			cnt = read(fileno(instr), buf, sizeof(buf));
2240 			CHECKOOB(return (-1))
2241 			else if (cnt < 0)
2242 				goto data_err;
2243 			if (cnt < 0)	/* resume after OOB */
2244 				continue;
2245 			if (cnt == 0)	/* EOF */
2246 				break;
2247 			for (len = cnt, bp = buf; len > 0;) {
2248 				cnt = write(fileno(outstr), bp, len);
2249 				CHECKOOB(return (-1))
2250 				else if (cnt < 0)
2251 					goto file_err;
2252 				if (cnt <= 0)
2253 					continue;
2254 				len -= cnt;
2255 				bp += cnt;
2256 				byte_count += cnt;
2257 			}
2258 		}
2259 		ENDXFER;
2260 		return (0);
2261 
2262 	case TYPE_E:
2263 		ENDXFER;
2264 		reply(553, "TYPE E not implemented.");
2265 		return (-1);
2266 
2267 	case TYPE_A:
2268 		cp = EOF;
2269 		for (;;) {
2270 			c = getc(instr);
2271 			CHECKOOB(return (-1))
2272 			else if (c == EOF && ferror(instr))
2273 				goto data_err;
2274 			if (c == EOF && ferror(instr)) { /* resume after OOB */
2275 				clearerr(instr);
2276 				continue;
2277 			}
2278 
2279 			if (cp == '\r') {
2280 				if (c != '\n')
2281 					FTPD_PUTC('\r', outstr, file_err);
2282 			} else
2283 				if (c == '\n')
2284 					bare_lfs++;
2285 			if (c == '\r') {
2286 				byte_count++;
2287 				cp = c;
2288 				continue;
2289 			}
2290 
2291 			/* Check for EOF here in order not to lose last \r. */
2292 			if (c == EOF) {
2293 				if (feof(instr))	/* EOF */
2294 					break;
2295 				syslog(LOG_ERR, "Internal: impossible condition"
2296 						" on data stream after getc()");
2297 				goto data_err;
2298 			}
2299 
2300 			byte_count++;
2301 			FTPD_PUTC(c, outstr, file_err);
2302 			cp = c;
2303 		}
2304 #ifdef notyet	/* BSD stdio isn't ready for that */
2305 		while (fflush(outstr) == EOF) {
2306 			CHECKOOB(return (-1))
2307 			else
2308 				goto file_err;
2309 			clearerr(outstr);
2310 		}
2311 		ENDXFER;
2312 #else
2313 		ENDXFER;
2314 		if (fflush(outstr) == EOF)
2315 			goto file_err;
2316 #endif
2317 		if (bare_lfs) {
2318 			lreply(226,
2319 		"WARNING! %d bare linefeeds received in ASCII mode.",
2320 			    bare_lfs);
2321 		(void)printf("   File may not have transferred correctly.\r\n");
2322 		}
2323 		return (0);
2324 	default:
2325 		ENDXFER;
2326 		reply(550, "Unimplemented TYPE %d in receive_data.", type);
2327 		return (-1);
2328 	}
2329 
2330 data_err:
2331 	ENDXFER;
2332 	perror_reply(426, "Data connection");
2333 	return (-1);
2334 
2335 file_err:
2336 	ENDXFER;
2337 	perror_reply(452, "Error writing to file");
2338 	return (-1);
2339 }
2340 
2341 void
2342 statfilecmd(char *filename)
2343 {
2344 	FILE *fin;
2345 	int atstart;
2346 	int c, code;
2347 	char line[LINE_MAX];
2348 	struct stat st;
2349 
2350 	code = lstat(filename, &st) == 0 && S_ISDIR(st.st_mode) ? 212 : 213;
2351 	(void)snprintf(line, sizeof(line), _PATH_LS " -lgA %s", filename);
2352 	fin = ftpd_popen(line, "r");
2353 	if (fin == NULL) {
2354 		perror_reply(551, filename);
2355 		return;
2356 	}
2357 	lreply(code, "Status of %s:", filename);
2358 	atstart = 1;
2359 	while ((c = getc(fin)) != EOF) {
2360 		if (c == '\n') {
2361 			if (ferror(stdout)){
2362 				perror_reply(421, "Control connection");
2363 				(void) ftpd_pclose(fin);
2364 				dologout(1);
2365 				/* NOTREACHED */
2366 			}
2367 			if (ferror(fin)) {
2368 				perror_reply(551, filename);
2369 				(void) ftpd_pclose(fin);
2370 				return;
2371 			}
2372 			(void) putc('\r', stdout);
2373 		}
2374 		/*
2375 		 * RFC 959 says neutral text should be prepended before
2376 		 * a leading 3-digit number followed by whitespace, but
2377 		 * many ftp clients can be confused by any leading digits,
2378 		 * as a matter of fact.
2379 		 */
2380 		if (atstart && isdigit(c))
2381 			(void) putc(' ', stdout);
2382 		(void) putc(c, stdout);
2383 		atstart = (c == '\n');
2384 	}
2385 	(void) ftpd_pclose(fin);
2386 	reply(code, "End of status.");
2387 }
2388 
2389 void
2390 statcmd(void)
2391 {
2392 	union sockunion *su;
2393 	u_char *a, *p;
2394 	char hname[NI_MAXHOST];
2395 	int ispassive;
2396 
2397 	if (hostinfo) {
2398 		lreply(211, "%s FTP server status:", hostname);
2399 		printf("     %s\r\n", version);
2400 	} else
2401 		lreply(211, "FTP server status:");
2402 	printf("     Connected to %s", remotehost);
2403 	if (!getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
2404 			 hname, sizeof(hname) - 1, NULL, 0, NI_NUMERICHOST)) {
2405 		hname[sizeof(hname) - 1] = 0;
2406 		if (strcmp(hname, remotehost) != 0)
2407 			printf(" (%s)", hname);
2408 	}
2409 	printf("\r\n");
2410 	if (logged_in) {
2411 		if (guest)
2412 			printf("     Logged in anonymously\r\n");
2413 		else
2414 			printf("     Logged in as %s\r\n", pw->pw_name);
2415 	} else if (askpasswd)
2416 		printf("     Waiting for password\r\n");
2417 	else
2418 		printf("     Waiting for user name\r\n");
2419 	printf("     TYPE: %s", typenames[type]);
2420 	if (type == TYPE_A || type == TYPE_E)
2421 		printf(", FORM: %s", formnames[form]);
2422 	if (type == TYPE_L)
2423 #if CHAR_BIT == 8
2424 		printf(" %d", CHAR_BIT);
2425 #else
2426 		printf(" %d", bytesize);	/* need definition! */
2427 #endif
2428 	printf("; STRUcture: %s; transfer MODE: %s\r\n",
2429 	    strunames[stru], modenames[mode]);
2430 	if (data != -1)
2431 		printf("     Data connection open\r\n");
2432 	else if (pdata != -1) {
2433 		ispassive = 1;
2434 		su = &pasv_addr;
2435 		goto printaddr;
2436 	} else if (usedefault == 0) {
2437 		ispassive = 0;
2438 		su = &data_dest;
2439 printaddr:
2440 #define UC(b) (((int) b) & 0xff)
2441 		if (epsvall) {
2442 			printf("     EPSV only mode (EPSV ALL)\r\n");
2443 			goto epsvonly;
2444 		}
2445 
2446 		/* PORT/PASV */
2447 		if (su->su_family == AF_INET) {
2448 			a = (u_char *) &su->su_sin.sin_addr;
2449 			p = (u_char *) &su->su_sin.sin_port;
2450 			printf("     %s (%d,%d,%d,%d,%d,%d)\r\n",
2451 				ispassive ? "PASV" : "PORT",
2452 				UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
2453 				UC(p[0]), UC(p[1]));
2454 		}
2455 
2456 		/* LPRT/LPSV */
2457 	    {
2458 		int alen, af, i;
2459 
2460 		switch (su->su_family) {
2461 		case AF_INET:
2462 			a = (u_char *) &su->su_sin.sin_addr;
2463 			p = (u_char *) &su->su_sin.sin_port;
2464 			alen = sizeof(su->su_sin.sin_addr);
2465 			af = 4;
2466 			break;
2467 		case AF_INET6:
2468 			a = (u_char *) &su->su_sin6.sin6_addr;
2469 			p = (u_char *) &su->su_sin6.sin6_port;
2470 			alen = sizeof(su->su_sin6.sin6_addr);
2471 			af = 6;
2472 			break;
2473 		default:
2474 			af = 0;
2475 			break;
2476 		}
2477 		if (af) {
2478 			printf("     %s (%d,%d,", ispassive ? "LPSV" : "LPRT",
2479 				af, alen);
2480 			for (i = 0; i < alen; i++)
2481 				printf("%d,", UC(a[i]));
2482 			printf("%d,%d,%d)\r\n", 2, UC(p[0]), UC(p[1]));
2483 		}
2484 	    }
2485 
2486 epsvonly:;
2487 		/* EPRT/EPSV */
2488 	    {
2489 		int af;
2490 
2491 		switch (su->su_family) {
2492 		case AF_INET:
2493 			af = 1;
2494 			break;
2495 		case AF_INET6:
2496 			af = 2;
2497 			break;
2498 		default:
2499 			af = 0;
2500 			break;
2501 		}
2502 		if (af) {
2503 			union sockunion tmp;
2504 
2505 			tmp = *su;
2506 			if (tmp.su_family == AF_INET6)
2507 				tmp.su_sin6.sin6_scope_id = 0;
2508 			if (!getnameinfo((struct sockaddr *)&tmp, tmp.su_len,
2509 					hname, sizeof(hname) - 1, NULL, 0,
2510 					NI_NUMERICHOST)) {
2511 				hname[sizeof(hname) - 1] = 0;
2512 				printf("     %s |%d|%s|%d|\r\n",
2513 					ispassive ? "EPSV" : "EPRT",
2514 					af, hname, htons(tmp.su_port));
2515 			}
2516 		}
2517 	    }
2518 #undef UC
2519 	} else
2520 		printf("     No data connection\r\n");
2521 	reply(211, "End of status.");
2522 }
2523 
2524 void
2525 fatalerror(char *s)
2526 {
2527 
2528 	reply(451, "Error in server: %s", s);
2529 	reply(221, "Closing connection due to server error.");
2530 	dologout(0);
2531 	/* NOTREACHED */
2532 }
2533 
2534 void
2535 reply(int n, const char *fmt, ...)
2536 {
2537 	va_list ap;
2538 
2539 	(void)printf("%d ", n);
2540 	va_start(ap, fmt);
2541 	(void)vprintf(fmt, ap);
2542 	va_end(ap);
2543 	(void)printf("\r\n");
2544 	(void)fflush(stdout);
2545 	if (ftpdebug) {
2546 		syslog(LOG_DEBUG, "<--- %d ", n);
2547 		va_start(ap, fmt);
2548 		vsyslog(LOG_DEBUG, fmt, ap);
2549 		va_end(ap);
2550 	}
2551 }
2552 
2553 void
2554 lreply(int n, const char *fmt, ...)
2555 {
2556 	va_list ap;
2557 
2558 	(void)printf("%d- ", n);
2559 	va_start(ap, fmt);
2560 	(void)vprintf(fmt, ap);
2561 	va_end(ap);
2562 	(void)printf("\r\n");
2563 	(void)fflush(stdout);
2564 	if (ftpdebug) {
2565 		syslog(LOG_DEBUG, "<--- %d- ", n);
2566 		va_start(ap, fmt);
2567 		vsyslog(LOG_DEBUG, fmt, ap);
2568 		va_end(ap);
2569 	}
2570 }
2571 
2572 static void
2573 ack(char *s)
2574 {
2575 
2576 	reply(250, "%s command successful.", s);
2577 }
2578 
2579 void
2580 nack(char *s)
2581 {
2582 
2583 	reply(502, "%s command not implemented.", s);
2584 }
2585 
2586 /* ARGSUSED */
2587 void
2588 yyerror(char *s)
2589 {
2590 	char *cp;
2591 
2592 	if ((cp = strchr(cbuf,'\n')))
2593 		*cp = '\0';
2594 	reply(500, "%s: command not understood.", cbuf);
2595 }
2596 
2597 void
2598 delete(char *name)
2599 {
2600 	struct stat st;
2601 
2602 	LOGCMD("delete", name);
2603 	if (lstat(name, &st) < 0) {
2604 		perror_reply(550, name);
2605 		return;
2606 	}
2607 	if (S_ISDIR(st.st_mode)) {
2608 		if (rmdir(name) < 0) {
2609 			perror_reply(550, name);
2610 			return;
2611 		}
2612 		goto done;
2613 	}
2614 	if (guest && noguestmod) {
2615 		reply(550, "Operation not permitted.");
2616 		return;
2617 	}
2618 	if (unlink(name) < 0) {
2619 		perror_reply(550, name);
2620 		return;
2621 	}
2622 done:
2623 	ack("DELE");
2624 }
2625 
2626 void
2627 cwd(char *path)
2628 {
2629 
2630 	if (chdir(path) < 0)
2631 		perror_reply(550, path);
2632 	else
2633 		ack("CWD");
2634 }
2635 
2636 void
2637 makedir(char *name)
2638 {
2639 	char *s;
2640 
2641 	LOGCMD("mkdir", name);
2642 	if (guest && noguestmkd)
2643 		reply(550, "Operation not permitted.");
2644 	else if (mkdir(name, 0777) < 0)
2645 		perror_reply(550, name);
2646 	else {
2647 		if ((s = doublequote(name)) == NULL)
2648 			fatalerror("Ran out of memory.");
2649 		reply(257, "\"%s\" directory created.", s);
2650 		free(s);
2651 	}
2652 }
2653 
2654 void
2655 removedir(char *name)
2656 {
2657 
2658 	LOGCMD("rmdir", name);
2659 	if (rmdir(name) < 0)
2660 		perror_reply(550, name);
2661 	else
2662 		ack("RMD");
2663 }
2664 
2665 void
2666 pwd(void)
2667 {
2668 	char *s, path[MAXPATHLEN + 1];
2669 
2670 	if (getcwd(path, sizeof(path)) == NULL)
2671 		perror_reply(550, "Get current directory");
2672 	else {
2673 		if ((s = doublequote(path)) == NULL)
2674 			fatalerror("Ran out of memory.");
2675 		reply(257, "\"%s\" is current directory.", s);
2676 		free(s);
2677 	}
2678 }
2679 
2680 char *
2681 renamefrom(char *name)
2682 {
2683 	struct stat st;
2684 
2685 	if (guest && noguestmod) {
2686 		reply(550, "Operation not permitted.");
2687 		return (NULL);
2688 	}
2689 	if (lstat(name, &st) < 0) {
2690 		perror_reply(550, name);
2691 		return (NULL);
2692 	}
2693 	reply(350, "File exists, ready for destination name.");
2694 	return (name);
2695 }
2696 
2697 void
2698 renamecmd(char *from, char *to)
2699 {
2700 	struct stat st;
2701 
2702 	LOGCMD2("rename", from, to);
2703 
2704 	if (guest && (stat(to, &st) == 0)) {
2705 		reply(550, "%s: permission denied.", to);
2706 		return;
2707 	}
2708 
2709 	if (rename(from, to) < 0)
2710 		perror_reply(550, "rename");
2711 	else
2712 		ack("RNTO");
2713 }
2714 
2715 static void
2716 dolog(struct sockaddr *who)
2717 {
2718 	char who_name[NI_MAXHOST];
2719 
2720 	realhostname_sa(remotehost, sizeof(remotehost) - 1, who, who->sa_len);
2721 	remotehost[sizeof(remotehost) - 1] = 0;
2722 	if (getnameinfo(who, who->sa_len,
2723 		who_name, sizeof(who_name) - 1, NULL, 0, NI_NUMERICHOST))
2724 			*who_name = 0;
2725 	who_name[sizeof(who_name) - 1] = 0;
2726 
2727 #ifdef SETPROCTITLE
2728 #ifdef VIRTUAL_HOSTING
2729 	if (thishost != firsthost)
2730 		snprintf(proctitle, sizeof(proctitle), "%s: connected (to %s)",
2731 			 remotehost, hostname);
2732 	else
2733 #endif
2734 		snprintf(proctitle, sizeof(proctitle), "%s: connected",
2735 			 remotehost);
2736 	setproctitle("%s", proctitle);
2737 #endif /* SETPROCTITLE */
2738 
2739 	if (logging) {
2740 #ifdef VIRTUAL_HOSTING
2741 		if (thishost != firsthost)
2742 			syslog(LOG_INFO, "connection from %s (%s) to %s",
2743 			       remotehost, who_name, hostname);
2744 		else
2745 #endif
2746 			syslog(LOG_INFO, "connection from %s (%s)",
2747 			       remotehost, who_name);
2748 	}
2749 }
2750 
2751 /*
2752  * Record logout in wtmp file
2753  * and exit with supplied status.
2754  */
2755 void
2756 dologout(int status)
2757 {
2758 
2759 	if (logged_in && dowtmp) {
2760 		(void) seteuid(0);
2761 		ftpd_logwtmp(wtmpid, NULL, NULL);
2762 	}
2763 	/* beware of flushing buffers after a SIGPIPE */
2764 	_exit(status);
2765 }
2766 
2767 static void
2768 sigurg(int signo)
2769 {
2770 
2771 	recvurg = 1;
2772 }
2773 
2774 static void
2775 maskurg(int flag)
2776 {
2777 	int oerrno;
2778 	sigset_t sset;
2779 
2780 	if (!transflag) {
2781 		syslog(LOG_ERR, "Internal: maskurg() while no transfer");
2782 		return;
2783 	}
2784 	oerrno = errno;
2785 	sigemptyset(&sset);
2786 	sigaddset(&sset, SIGURG);
2787 	sigprocmask(flag ? SIG_BLOCK : SIG_UNBLOCK, &sset, NULL);
2788 	errno = oerrno;
2789 }
2790 
2791 static void
2792 flagxfer(int flag)
2793 {
2794 
2795 	if (flag) {
2796 		if (transflag)
2797 			syslog(LOG_ERR, "Internal: flagxfer(1): "
2798 					"transfer already under way");
2799 		transflag = 1;
2800 		maskurg(0);
2801 		recvurg = 0;
2802 	} else {
2803 		if (!transflag)
2804 			syslog(LOG_ERR, "Internal: flagxfer(0): "
2805 					"no active transfer");
2806 		maskurg(1);
2807 		transflag = 0;
2808 	}
2809 }
2810 
2811 /*
2812  * Returns 0 if OK to resume or -1 if abort requested.
2813  */
2814 static int
2815 myoob(void)
2816 {
2817 	char *cp;
2818 	int ret;
2819 
2820 	if (!transflag) {
2821 		syslog(LOG_ERR, "Internal: myoob() while no transfer");
2822 		return (0);
2823 	}
2824 	cp = tmpline;
2825 	ret = getline(cp, 7, stdin);
2826 	if (ret == -1) {
2827 		reply(221, "You could at least say goodbye.");
2828 		dologout(0);
2829 	} else if (ret == -2) {
2830 		/* Ignore truncated command. */
2831 		return (0);
2832 	}
2833 	upper(cp);
2834 	if (strcmp(cp, "ABOR\r\n") == 0) {
2835 		tmpline[0] = '\0';
2836 		reply(426, "Transfer aborted. Data connection closed.");
2837 		reply(226, "Abort successful.");
2838 		return (-1);
2839 	}
2840 	if (strcmp(cp, "STAT\r\n") == 0) {
2841 		tmpline[0] = '\0';
2842 		if (file_size != -1)
2843 			reply(213, "Status: %jd of %jd bytes transferred.",
2844 				   (intmax_t)byte_count, (intmax_t)file_size);
2845 		else
2846 			reply(213, "Status: %jd bytes transferred.",
2847 				   (intmax_t)byte_count);
2848 	}
2849 	return (0);
2850 }
2851 
2852 /*
2853  * Note: a response of 425 is not mentioned as a possible response to
2854  *	the PASV command in RFC959. However, it has been blessed as
2855  *	a legitimate response by Jon Postel in a telephone conversation
2856  *	with Rick Adams on 25 Jan 89.
2857  */
2858 void
2859 passive(void)
2860 {
2861 	socklen_t len;
2862 	int on;
2863 	char *p, *a;
2864 
2865 	if (pdata >= 0)		/* close old port if one set */
2866 		close(pdata);
2867 
2868 	pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
2869 	if (pdata < 0) {
2870 		perror_reply(425, "Can't open passive connection");
2871 		return;
2872 	}
2873 	on = 1;
2874 	if (setsockopt(pdata, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
2875 		syslog(LOG_WARNING, "pdata setsockopt (SO_REUSEADDR): %m");
2876 
2877 	(void) seteuid(0);
2878 
2879 #ifdef IP_PORTRANGE
2880 	if (ctrl_addr.su_family == AF_INET) {
2881 	    on = restricted_data_ports ? IP_PORTRANGE_HIGH
2882 				       : IP_PORTRANGE_DEFAULT;
2883 
2884 	    if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE,
2885 			    &on, sizeof(on)) < 0)
2886 		    goto pasv_error;
2887 	}
2888 #endif
2889 #ifdef IPV6_PORTRANGE
2890 	if (ctrl_addr.su_family == AF_INET6) {
2891 	    on = restricted_data_ports ? IPV6_PORTRANGE_HIGH
2892 				       : IPV6_PORTRANGE_DEFAULT;
2893 
2894 	    if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE,
2895 			    &on, sizeof(on)) < 0)
2896 		    goto pasv_error;
2897 	}
2898 #endif
2899 
2900 	pasv_addr = ctrl_addr;
2901 	pasv_addr.su_port = 0;
2902 	if (bind(pdata, (struct sockaddr *)&pasv_addr, pasv_addr.su_len) < 0)
2903 		goto pasv_error;
2904 
2905 	(void) seteuid(pw->pw_uid);
2906 
2907 	len = sizeof(pasv_addr);
2908 	if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0)
2909 		goto pasv_error;
2910 	if (listen(pdata, 1) < 0)
2911 		goto pasv_error;
2912 	if (pasv_addr.su_family == AF_INET)
2913 		a = (char *) &pasv_addr.su_sin.sin_addr;
2914 	else if (pasv_addr.su_family == AF_INET6 &&
2915 		 IN6_IS_ADDR_V4MAPPED(&pasv_addr.su_sin6.sin6_addr))
2916 		a = (char *) &pasv_addr.su_sin6.sin6_addr.s6_addr[12];
2917 	else
2918 		goto pasv_error;
2919 
2920 	p = (char *) &pasv_addr.su_port;
2921 
2922 #define UC(b) (((int) b) & 0xff)
2923 
2924 	reply(227, "Entering Passive Mode (%d,%d,%d,%d,%d,%d)", UC(a[0]),
2925 		UC(a[1]), UC(a[2]), UC(a[3]), UC(p[0]), UC(p[1]));
2926 	return;
2927 
2928 pasv_error:
2929 	(void) seteuid(pw->pw_uid);
2930 	(void) close(pdata);
2931 	pdata = -1;
2932 	perror_reply(425, "Can't open passive connection");
2933 	return;
2934 }
2935 
2936 /*
2937  * Long Passive defined in RFC 1639.
2938  *     228 Entering Long Passive Mode
2939  *         (af, hal, h1, h2, h3,..., pal, p1, p2...)
2940  */
2941 
2942 void
2943 long_passive(char *cmd, int pf)
2944 {
2945 	socklen_t len;
2946 	int on;
2947 	char *p, *a;
2948 
2949 	if (pdata >= 0)		/* close old port if one set */
2950 		close(pdata);
2951 
2952 	if (pf != PF_UNSPEC) {
2953 		if (ctrl_addr.su_family != pf) {
2954 			switch (ctrl_addr.su_family) {
2955 			case AF_INET:
2956 				pf = 1;
2957 				break;
2958 			case AF_INET6:
2959 				pf = 2;
2960 				break;
2961 			default:
2962 				pf = 0;
2963 				break;
2964 			}
2965 			/*
2966 			 * XXX
2967 			 * only EPRT/EPSV ready clients will understand this
2968 			 */
2969 			if (strcmp(cmd, "EPSV") == 0 && pf) {
2970 				reply(522, "Network protocol mismatch, "
2971 					"use (%d)", pf);
2972 			} else
2973 				reply(501, "Network protocol mismatch."); /*XXX*/
2974 
2975 			return;
2976 		}
2977 	}
2978 
2979 	pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
2980 	if (pdata < 0) {
2981 		perror_reply(425, "Can't open passive connection");
2982 		return;
2983 	}
2984 	on = 1;
2985 	if (setsockopt(pdata, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
2986 		syslog(LOG_WARNING, "pdata setsockopt (SO_REUSEADDR): %m");
2987 
2988 	(void) seteuid(0);
2989 
2990 	pasv_addr = ctrl_addr;
2991 	pasv_addr.su_port = 0;
2992 	len = pasv_addr.su_len;
2993 
2994 #ifdef IP_PORTRANGE
2995 	if (ctrl_addr.su_family == AF_INET) {
2996 	    on = restricted_data_ports ? IP_PORTRANGE_HIGH
2997 				       : IP_PORTRANGE_DEFAULT;
2998 
2999 	    if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE,
3000 			    &on, sizeof(on)) < 0)
3001 		    goto pasv_error;
3002 	}
3003 #endif
3004 #ifdef IPV6_PORTRANGE
3005 	if (ctrl_addr.su_family == AF_INET6) {
3006 	    on = restricted_data_ports ? IPV6_PORTRANGE_HIGH
3007 				       : IPV6_PORTRANGE_DEFAULT;
3008 
3009 	    if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE,
3010 			    &on, sizeof(on)) < 0)
3011 		    goto pasv_error;
3012 	}
3013 #endif
3014 
3015 	if (bind(pdata, (struct sockaddr *)&pasv_addr, len) < 0)
3016 		goto pasv_error;
3017 
3018 	(void) seteuid(pw->pw_uid);
3019 
3020 	if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0)
3021 		goto pasv_error;
3022 	if (listen(pdata, 1) < 0)
3023 		goto pasv_error;
3024 
3025 #define UC(b) (((int) b) & 0xff)
3026 
3027 	if (strcmp(cmd, "LPSV") == 0) {
3028 		p = (char *)&pasv_addr.su_port;
3029 		switch (pasv_addr.su_family) {
3030 		case AF_INET:
3031 			a = (char *) &pasv_addr.su_sin.sin_addr;
3032 		v4_reply:
3033 			reply(228,
3034 "Entering Long Passive Mode (%d,%d,%d,%d,%d,%d,%d,%d,%d)",
3035 			      4, 4, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
3036 			      2, UC(p[0]), UC(p[1]));
3037 			return;
3038 		case AF_INET6:
3039 			if (IN6_IS_ADDR_V4MAPPED(&pasv_addr.su_sin6.sin6_addr)) {
3040 				a = (char *) &pasv_addr.su_sin6.sin6_addr.s6_addr[12];
3041 				goto v4_reply;
3042 			}
3043 			a = (char *) &pasv_addr.su_sin6.sin6_addr;
3044 			reply(228,
3045 "Entering Long Passive Mode "
3046 "(%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d)",
3047 			      6, 16, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
3048 			      UC(a[4]), UC(a[5]), UC(a[6]), UC(a[7]),
3049 			      UC(a[8]), UC(a[9]), UC(a[10]), UC(a[11]),
3050 			      UC(a[12]), UC(a[13]), UC(a[14]), UC(a[15]),
3051 			      2, UC(p[0]), UC(p[1]));
3052 			return;
3053 		}
3054 	} else if (strcmp(cmd, "EPSV") == 0) {
3055 		switch (pasv_addr.su_family) {
3056 		case AF_INET:
3057 		case AF_INET6:
3058 			reply(229, "Entering Extended Passive Mode (|||%d|)",
3059 				ntohs(pasv_addr.su_port));
3060 			return;
3061 		}
3062 	} else {
3063 		/* more proper error code? */
3064 	}
3065 
3066 pasv_error:
3067 	(void) seteuid(pw->pw_uid);
3068 	(void) close(pdata);
3069 	pdata = -1;
3070 	perror_reply(425, "Can't open passive connection");
3071 	return;
3072 }
3073 
3074 /*
3075  * Generate unique name for file with basename "local"
3076  * and open the file in order to avoid possible races.
3077  * Try "local" first, then "local.1", "local.2" etc, up to "local.99".
3078  * Return descriptor to the file, set "name" to its name.
3079  *
3080  * Generates failure reply on error.
3081  */
3082 static int
3083 guniquefd(char *local, char **name)
3084 {
3085 	static char new[MAXPATHLEN];
3086 	struct stat st;
3087 	char *cp;
3088 	int count;
3089 	int fd;
3090 
3091 	cp = strrchr(local, '/');
3092 	if (cp)
3093 		*cp = '\0';
3094 	if (stat(cp ? local : ".", &st) < 0) {
3095 		perror_reply(553, cp ? local : ".");
3096 		return (-1);
3097 	}
3098 	if (cp) {
3099 		/*
3100 		 * Let not overwrite dirname with counter suffix.
3101 		 * -4 is for /nn\0
3102 		 * In this extreme case dot won't be put in front of suffix.
3103 		 */
3104 		if (strlen(local) > sizeof(new) - 4) {
3105 			reply(553, "Pathname too long.");
3106 			return (-1);
3107 		}
3108 		*cp = '/';
3109 	}
3110 	/* -4 is for the .nn<null> we put on the end below */
3111 	(void) snprintf(new, sizeof(new) - 4, "%s", local);
3112 	cp = new + strlen(new);
3113 	/*
3114 	 * Don't generate dotfile unless requested explicitly.
3115 	 * This covers the case when basename gets truncated off
3116 	 * by buffer size.
3117 	 */
3118 	if (cp > new && cp[-1] != '/')
3119 		*cp++ = '.';
3120 	for (count = 0; count < 100; count++) {
3121 		/* At count 0 try unmodified name */
3122 		if (count)
3123 			(void)sprintf(cp, "%d", count);
3124 		if ((fd = open(count ? new : local,
3125 		    O_RDWR | O_CREAT | O_EXCL, 0666)) >= 0) {
3126 			*name = count ? new : local;
3127 			return (fd);
3128 		}
3129 		if (errno != EEXIST) {
3130 			perror_reply(553, count ? new : local);
3131 			return (-1);
3132 		}
3133 	}
3134 	reply(452, "Unique file name cannot be created.");
3135 	return (-1);
3136 }
3137 
3138 /*
3139  * Format and send reply containing system error number.
3140  */
3141 void
3142 perror_reply(int code, char *string)
3143 {
3144 
3145 	reply(code, "%s: %s.", string, strerror(errno));
3146 }
3147 
3148 static char *onefile[] = {
3149 	"",
3150 	0
3151 };
3152 
3153 void
3154 send_file_list(char *whichf)
3155 {
3156 	struct stat st;
3157 	DIR *dirp = NULL;
3158 	struct dirent *dir;
3159 	FILE *dout = NULL;
3160 	char **dirlist, *dirname;
3161 	int simple = 0;
3162 	int freeglob = 0;
3163 	glob_t gl;
3164 
3165 	if (strpbrk(whichf, "~{[*?") != NULL) {
3166 		int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE;
3167 
3168 		memset(&gl, 0, sizeof(gl));
3169 		gl.gl_matchc = MAXGLOBARGS;
3170 		flags |= GLOB_LIMIT;
3171 		freeglob = 1;
3172 		if (glob(whichf, flags, 0, &gl)) {
3173 			reply(550, "No matching files found.");
3174 			goto out;
3175 		} else if (gl.gl_pathc == 0) {
3176 			errno = ENOENT;
3177 			perror_reply(550, whichf);
3178 			goto out;
3179 		}
3180 		dirlist = gl.gl_pathv;
3181 	} else {
3182 		onefile[0] = whichf;
3183 		dirlist = onefile;
3184 		simple = 1;
3185 	}
3186 
3187 	while ((dirname = *dirlist++)) {
3188 		if (stat(dirname, &st) < 0) {
3189 			/*
3190 			 * If user typed "ls -l", etc, and the client
3191 			 * used NLST, do what the user meant.
3192 			 */
3193 			if (dirname[0] == '-' && *dirlist == NULL &&
3194 			    dout == NULL)
3195 				retrieve(_PATH_LS " %s", dirname);
3196 			else
3197 				perror_reply(550, whichf);
3198 			goto out;
3199 		}
3200 
3201 		if (S_ISREG(st.st_mode)) {
3202 			if (dout == NULL) {
3203 				dout = dataconn("file list", -1, "w");
3204 				if (dout == NULL)
3205 					goto out;
3206 				STARTXFER;
3207 			}
3208 			START_UNSAFE;
3209 			fprintf(dout, "%s%s\n", dirname,
3210 				type == TYPE_A ? "\r" : "");
3211 			END_UNSAFE;
3212 			if (ferror(dout))
3213 				goto data_err;
3214 			byte_count += strlen(dirname) +
3215 				      (type == TYPE_A ? 2 : 1);
3216 			CHECKOOB(goto abrt);
3217 			continue;
3218 		} else if (!S_ISDIR(st.st_mode))
3219 			continue;
3220 
3221 		if ((dirp = opendir(dirname)) == NULL)
3222 			continue;
3223 
3224 		while ((dir = readdir(dirp)) != NULL) {
3225 			char nbuf[MAXPATHLEN];
3226 
3227 			CHECKOOB(goto abrt);
3228 
3229 			if (dir->d_name[0] == '.' && dir->d_namlen == 1)
3230 				continue;
3231 			if (dir->d_name[0] == '.' && dir->d_name[1] == '.' &&
3232 			    dir->d_namlen == 2)
3233 				continue;
3234 
3235 			snprintf(nbuf, sizeof(nbuf),
3236 				"%s/%s", dirname, dir->d_name);
3237 
3238 			/*
3239 			 * We have to do a stat to insure it's
3240 			 * not a directory or special file.
3241 			 */
3242 			if (simple || (stat(nbuf, &st) == 0 &&
3243 			    S_ISREG(st.st_mode))) {
3244 				if (dout == NULL) {
3245 					dout = dataconn("file list", -1, "w");
3246 					if (dout == NULL)
3247 						goto out;
3248 					STARTXFER;
3249 				}
3250 				START_UNSAFE;
3251 				if (nbuf[0] == '.' && nbuf[1] == '/')
3252 					fprintf(dout, "%s%s\n", &nbuf[2],
3253 						type == TYPE_A ? "\r" : "");
3254 				else
3255 					fprintf(dout, "%s%s\n", nbuf,
3256 						type == TYPE_A ? "\r" : "");
3257 				END_UNSAFE;
3258 				if (ferror(dout))
3259 					goto data_err;
3260 				byte_count += strlen(nbuf) +
3261 					      (type == TYPE_A ? 2 : 1);
3262 				CHECKOOB(goto abrt);
3263 			}
3264 		}
3265 		(void) closedir(dirp);
3266 		dirp = NULL;
3267 	}
3268 
3269 	if (dout == NULL)
3270 		reply(550, "No files found.");
3271 	else if (ferror(dout))
3272 data_err:	perror_reply(550, "Data connection");
3273 	else
3274 		reply(226, "Transfer complete.");
3275 out:
3276 	if (dout) {
3277 		ENDXFER;
3278 abrt:
3279 		(void) fclose(dout);
3280 		data = -1;
3281 		pdata = -1;
3282 	}
3283 	if (dirp)
3284 		(void) closedir(dirp);
3285 	if (freeglob) {
3286 		freeglob = 0;
3287 		globfree(&gl);
3288 	}
3289 }
3290 
3291 void
3292 reapchild(int signo)
3293 {
3294 	while (waitpid(-1, NULL, WNOHANG) > 0);
3295 }
3296 
3297 #ifdef OLD_SETPROCTITLE
3298 /*
3299  * Clobber argv so ps will show what we're doing.  (Stolen from sendmail.)
3300  * Warning, since this is usually started from inetd.conf, it often doesn't
3301  * have much of an environment or arglist to overwrite.
3302  */
3303 void
3304 setproctitle(const char *fmt, ...)
3305 {
3306 	int i;
3307 	va_list ap;
3308 	char *p, *bp, ch;
3309 	char buf[LINE_MAX];
3310 
3311 	va_start(ap, fmt);
3312 	(void)vsnprintf(buf, sizeof(buf), fmt, ap);
3313 
3314 	/* make ps print our process name */
3315 	p = Argv[0];
3316 	*p++ = '-';
3317 
3318 	i = strlen(buf);
3319 	if (i > LastArgv - p - 2) {
3320 		i = LastArgv - p - 2;
3321 		buf[i] = '\0';
3322 	}
3323 	bp = buf;
3324 	while (ch = *bp++)
3325 		if (ch != '\n' && ch != '\r')
3326 			*p++ = ch;
3327 	while (p < LastArgv)
3328 		*p++ = ' ';
3329 }
3330 #endif /* OLD_SETPROCTITLE */
3331 
3332 static void
3333 appendf(char **strp, char *fmt, ...)
3334 {
3335 	va_list ap;
3336 	char *ostr, *p;
3337 
3338 	va_start(ap, fmt);
3339 	vasprintf(&p, fmt, ap);
3340 	va_end(ap);
3341 	if (p == NULL)
3342 		fatalerror("Ran out of memory.");
3343 	if (*strp == NULL)
3344 		*strp = p;
3345 	else {
3346 		ostr = *strp;
3347 		asprintf(strp, "%s%s", ostr, p);
3348 		if (*strp == NULL)
3349 			fatalerror("Ran out of memory.");
3350 		free(ostr);
3351 	}
3352 }
3353 
3354 static void
3355 logcmd(char *cmd, char *file1, char *file2, off_t cnt)
3356 {
3357 	char *msg = NULL;
3358 	char wd[MAXPATHLEN + 1];
3359 
3360 	if (logging <= 1)
3361 		return;
3362 
3363 	if (getcwd(wd, sizeof(wd) - 1) == NULL)
3364 		strcpy(wd, strerror(errno));
3365 
3366 	appendf(&msg, "%s", cmd);
3367 	if (file1)
3368 		appendf(&msg, " %s", file1);
3369 	if (file2)
3370 		appendf(&msg, " %s", file2);
3371 	if (cnt >= 0)
3372 		appendf(&msg, " = %jd bytes", (intmax_t)cnt);
3373 	appendf(&msg, " (wd: %s", wd);
3374 	if (guest || dochroot)
3375 		appendf(&msg, "; chrooted");
3376 	appendf(&msg, ")");
3377 	syslog(LOG_INFO, "%s", msg);
3378 	free(msg);
3379 }
3380 
3381 static void
3382 logxfer(char *name, off_t size, time_t start)
3383 {
3384 	char buf[MAXPATHLEN + 1024];
3385 	char path[MAXPATHLEN + 1];
3386 	time_t now;
3387 
3388 	if (statfd >= 0) {
3389 		time(&now);
3390 		if (realpath(name, path) == NULL) {
3391 			syslog(LOG_NOTICE, "realpath failed on %s: %m", path);
3392 			return;
3393 		}
3394 		snprintf(buf, sizeof(buf), "%.20s!%s!%s!%s!%jd!%ld\n",
3395 			ctime(&now)+4, ident, remotehost,
3396 			path, (intmax_t)size,
3397 			(long)(now - start + (now == start)));
3398 		write(statfd, buf, strlen(buf));
3399 	}
3400 }
3401 
3402 static char *
3403 doublequote(char *s)
3404 {
3405 	int n;
3406 	char *p, *s2;
3407 
3408 	for (p = s, n = 0; *p; p++)
3409 		if (*p == '"')
3410 			n++;
3411 
3412 	if ((s2 = malloc(p - s + n + 1)) == NULL)
3413 		return (NULL);
3414 
3415 	for (p = s2; *s; s++, p++) {
3416 		if ((*p = *s) == '"')
3417 			*(++p) = '"';
3418 	}
3419 	*p = '\0';
3420 
3421 	return (s2);
3422 }
3423 
3424 /* setup server socket for specified address family */
3425 /* if af is PF_UNSPEC more than one socket may be returned */
3426 /* the returned list is dynamically allocated, so caller needs to free it */
3427 static int *
3428 socksetup(int af, char *bindname, const char *bindport)
3429 {
3430 	struct addrinfo hints, *res, *r;
3431 	int error, maxs, *s, *socks;
3432 	const int on = 1;
3433 
3434 	memset(&hints, 0, sizeof(hints));
3435 	hints.ai_flags = AI_PASSIVE;
3436 	hints.ai_family = af;
3437 	hints.ai_socktype = SOCK_STREAM;
3438 	error = getaddrinfo(bindname, bindport, &hints, &res);
3439 	if (error) {
3440 		syslog(LOG_ERR, "%s", gai_strerror(error));
3441 		if (error == EAI_SYSTEM)
3442 			syslog(LOG_ERR, "%s", strerror(errno));
3443 		return NULL;
3444 	}
3445 
3446 	/* Count max number of sockets we may open */
3447 	for (maxs = 0, r = res; r; r = r->ai_next, maxs++)
3448 		;
3449 	socks = malloc((maxs + 1) * sizeof(int));
3450 	if (!socks) {
3451 		freeaddrinfo(res);
3452 		syslog(LOG_ERR, "couldn't allocate memory for sockets");
3453 		return NULL;
3454 	}
3455 
3456 	*socks = 0;   /* num of sockets counter at start of array */
3457 	s = socks + 1;
3458 	for (r = res; r; r = r->ai_next) {
3459 		*s = socket(r->ai_family, r->ai_socktype, r->ai_protocol);
3460 		if (*s < 0) {
3461 			syslog(LOG_DEBUG, "control socket: %m");
3462 			continue;
3463 		}
3464 		if (setsockopt(*s, SOL_SOCKET, SO_REUSEADDR,
3465 		    &on, sizeof(on)) < 0)
3466 			syslog(LOG_WARNING,
3467 			    "control setsockopt (SO_REUSEADDR): %m");
3468 		if (r->ai_family == AF_INET6) {
3469 			if (setsockopt(*s, IPPROTO_IPV6, IPV6_V6ONLY,
3470 			    &on, sizeof(on)) < 0)
3471 				syslog(LOG_WARNING,
3472 				    "control setsockopt (IPV6_V6ONLY): %m");
3473 		}
3474 		if (bind(*s, r->ai_addr, r->ai_addrlen) < 0) {
3475 			syslog(LOG_DEBUG, "control bind: %m");
3476 			close(*s);
3477 			continue;
3478 		}
3479 		(*socks)++;
3480 		s++;
3481 	}
3482 
3483 	if (res)
3484 		freeaddrinfo(res);
3485 
3486 	if (*socks == 0) {
3487 		syslog(LOG_ERR, "control socket: Couldn't bind to any socket");
3488 		free(socks);
3489 		return NULL;
3490 	}
3491 	return(socks);
3492 }
3493