xref: /dragonfly/libexec/ftpd/ftpd.c (revision 2702099d)
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  * 4. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * @(#)ftpd.c	8.4 (Berkeley) 4/16/94
30  * $FreeBSD: src/libexec/ftpd/ftpd.c,v 1.213 2008/12/23 01:23:09 cperciva Exp $
31  */
32 
33 /*
34  * FTP server.
35  */
36 #include <sys/param.h>
37 #include <sys/ioctl.h>
38 #include <sys/mman.h>
39 #include <sys/socket.h>
40 #include <sys/stat.h>
41 #include <sys/time.h>
42 #include <sys/wait.h>
43 
44 #include <netinet/in.h>
45 #include <netinet/in_systm.h>
46 #include <netinet/ip.h>
47 #include <netinet/tcp.h>
48 
49 #define	FTP_NAMES
50 #include <arpa/ftp.h>
51 #include <arpa/inet.h>
52 #include <arpa/telnet.h>
53 
54 #include <ctype.h>
55 #include <dirent.h>
56 #include <err.h>
57 #include <errno.h>
58 #include <fcntl.h>
59 #include <glob.h>
60 #include <limits.h>
61 #include <netdb.h>
62 #include <pwd.h>
63 #include <grp.h>
64 #include <opie.h>
65 #include <signal.h>
66 #include <stdint.h>
67 #include <stdio.h>
68 #include <stdlib.h>
69 #include <string.h>
70 #include <syslog.h>
71 #include <time.h>
72 #include <unistd.h>
73 #include <libutil.h>
74 #ifdef	LOGIN_CAP
75 #include <login_cap.h>
76 #endif
77 
78 #ifdef USE_PAM
79 #include <security/pam_appl.h>
80 #endif
81 
82 #include "pathnames.h"
83 #include "extern.h"
84 #include "pidfile.h"
85 
86 #include <stdarg.h>
87 
88 static char version[] = "Version 6.00LS";
89 #undef main
90 
91 extern	off_t restart_point;
92 extern	char cbuf[];
93 
94 union sockunion ctrl_addr;
95 union sockunion data_source;
96 union sockunion data_dest;
97 union sockunion his_addr;
98 union sockunion pasv_addr;
99 
100 int	daemon_mode;
101 int	data;
102 int	dataport;
103 int	hostinfo = 1;	/* print host-specific info in messages */
104 int	logged_in;
105 struct	passwd *pw;
106 char	*homedir;
107 int	ftpdebug;
108 int	timeout = 900;    /* timeout after 15 minutes of inactivity */
109 int	maxtimeout = 7200;/* don't allow idle time to be set beyond 2 hours */
110 int	logging;
111 int	restricted_data_ports = 1;
112 int	paranoid = 1;	  /* be extra careful about security */
113 int	anon_only = 0;    /* Only anonymous ftp allowed */
114 int	assumeutf8 = 0;   /* Assume that server file names are in UTF-8 */
115 int	guest;
116 int	dochroot;
117 char	*chrootdir;
118 int	dowtmp = 1;
119 int	stats;
120 int	statfd = -1;
121 int	type;
122 int	form;
123 int	stru;			/* avoid C keyword */
124 int	mode;
125 int	usedefault = 1;		/* for data transfers */
126 int	pdata = -1;		/* for passive mode */
127 int	readonly = 0;		/* Server is in readonly mode.	*/
128 int	noepsv = 0;		/* EPSV command is disabled.	*/
129 int	noretr = 0;		/* RETR command is disabled.	*/
130 int	noguestretr = 0;	/* RETR command is disabled for anon users. */
131 int	noguestmkd = 0;		/* MKD command is disabled for anon users. */
132 int	noguestmod = 1;		/* anon users may not modify existing files. */
133 
134 off_t	file_size;
135 off_t	byte_count;
136 #if !defined(CMASK) || CMASK == 0
137 #undef CMASK
138 #define CMASK 027
139 #endif
140 int	defumask = CMASK;		/* default umask value */
141 char	tmpline[7];
142 char	*hostname;
143 int	epsvall = 0;
144 
145 #ifdef VIRTUAL_HOSTING
146 char	*ftpuser;
147 
148 static struct ftphost {
149 	struct ftphost	*next;
150 	struct addrinfo *hostinfo;
151 	char		*hostname;
152 	char		*anonuser;
153 	char		*statfile;
154 	char		*welcome;
155 	char		*loginmsg;
156 } *thishost, *firsthost;
157 
158 #endif
159 char	remotehost[NI_MAXHOST];
160 char	*ident = NULL;
161 
162 static char	ttyline[20];
163 char		*tty = ttyline;		/* for klogin */
164 
165 #ifdef USE_PAM
166 static int	auth_pam(struct passwd**, const char*);
167 pam_handle_t	*pamh = NULL;
168 #endif
169 
170 static struct opie	opiedata;
171 static char		opieprompt[OPIE_CHALLENGE_MAX+1];
172 static int		pwok;
173 
174 char	*pid_file = NULL; /* means default location to pidfile(3) */
175 
176 /*
177  * Limit number of pathnames that glob can return.
178  * A limit of 0 indicates the number of pathnames is unlimited.
179  */
180 #define MAXGLOBARGS	16384
181 #
182 
183 /*
184  * Timeout intervals for retrying connections
185  * to hosts that don't accept PORT cmds.  This
186  * is a kludge, but given the problems with TCP...
187  */
188 #define	SWAITMAX	90	/* wait at most 90 seconds */
189 #define	SWAITINT	5	/* interval between retries */
190 
191 int	swaitmax = SWAITMAX;
192 int	swaitint = SWAITINT;
193 
194 #ifdef SETPROCTITLE
195 char	proctitle[LINE_MAX];	/* initial part of title */
196 #endif /* SETPROCTITLE */
197 
198 #define LOGCMD(cmd, file)		logcmd((cmd), (file), NULL, -1)
199 #define LOGCMD2(cmd, file1, file2)	logcmd((cmd), (file1), (file2), -1)
200 #define LOGBYTES(cmd, file, cnt)	logcmd((cmd), (file), NULL, (cnt))
201 
202 static	volatile sig_atomic_t recvurg;
203 static	int transflag;		/* NB: for debugging only */
204 
205 #define STARTXFER	flagxfer(1)
206 #define ENDXFER		flagxfer(0)
207 
208 #define START_UNSAFE	maskurg(1)
209 #define END_UNSAFE	maskurg(0)
210 
211 /* It's OK to put an `else' clause after this macro. */
212 #define CHECKOOB(action)						\
213 	if (recvurg) {							\
214 		recvurg = 0;						\
215 		if (myoob()) {						\
216 			ENDXFER;					\
217 			action;						\
218 		}							\
219 	}
220 
221 #ifdef VIRTUAL_HOSTING
222 static void	 inithosts(int);
223 static void	 selecthost(union sockunion *);
224 #endif
225 static void	 ack(char *);
226 static void	 sigurg(int);
227 static void	 maskurg(int);
228 static void	 flagxfer(int);
229 static int	 myoob(void);
230 static int	 checkuser(char *, char *, int, char **);
231 static FILE	*dataconn(char *, off_t, char *);
232 static void	 dolog(struct sockaddr *);
233 static void	 end_login(void);
234 static FILE	*getdatasock(char *);
235 static int	 guniquefd(char *, char **);
236 static void	 lostconn(int);
237 static void	 sigquit(int);
238 static int	 receive_data(FILE *, FILE *);
239 static int	 send_data(FILE *, FILE *, size_t, off_t, int);
240 static struct passwd *
241 		 sgetpwnam(char *);
242 static char	*sgetsave(char *);
243 static void	 reapchild(int);
244 static void	 appendf(char **, char *, ...) __printflike(2, 3);
245 static void	 logcmd(char *, char *, char *, off_t);
246 static void      logxfer(char *, off_t, time_t);
247 static char	*doublequote(char *);
248 static int	*socksetup(int, char *, const char *);
249 
250 int
251 main(int argc, char *argv[])
252 {
253 	socklen_t addrlen;
254 	int ch, on = 1, tos;
255 	char *cp, line[LINE_MAX];
256 	FILE *fd;
257 	char	*bindname = NULL;
258 	const char *bindport = "ftp";
259 	int	family = AF_UNSPEC;
260 	struct sigaction sa;
261 
262 	tzset();		/* in case no timezone database in ~ftp */
263 	sigemptyset(&sa.sa_mask);
264 	sa.sa_flags = SA_RESTART;
265 
266 	/*
267 	 * Prevent diagnostic messages from appearing on stderr.
268 	 * We run as a daemon or from inetd; in both cases, there's
269 	 * more reason in logging to syslog.
270 	 */
271 	freopen(_PATH_DEVNULL, "w", stderr);
272 	opterr = 0;
273 
274 	/*
275 	 * LOG_NDELAY sets up the logging connection immediately,
276 	 * necessary for anonymous ftp's that chroot and can't do it later.
277 	 */
278 	openlog("ftpd", LOG_PID | LOG_NDELAY, LOG_FTP);
279 
280 	while ((ch = getopt(argc, argv,
281 	                    "468a:AdDEH:hlmMoOp:P:rRSt:T:u:UvW")) != -1) {
282 		switch (ch) {
283 		case '4':
284 			family = (family == AF_INET6) ? AF_UNSPEC : AF_INET;
285 			break;
286 
287 		case '6':
288 			family = (family == AF_INET) ? AF_UNSPEC : AF_INET6;
289 			break;
290 
291 		case '8':
292 			assumeutf8 = 1;
293 			break;
294 
295 		case 'a':
296 			bindname = optarg;
297 			break;
298 
299 		case 'A':
300 			anon_only = 1;
301 			break;
302 
303 		case 'd':
304 			ftpdebug++;
305 			break;
306 
307 		case 'D':
308 			daemon_mode++;
309 			break;
310 
311 		case 'E':
312 			noepsv = 1;
313 			break;
314 
315 		case 'h':
316 			hostinfo = 0;
317 			break;
318 
319 		case 'H':
320 			hostname = optarg;
321 			break;
322 
323 		case 'l':
324 			logging++;	/* > 1 == extra logging */
325 			break;
326 
327 		case 'm':
328 			noguestmod = 0;
329 			break;
330 
331 		case 'M':
332 			noguestmkd = 1;
333 			break;
334 
335 		case 'o':
336 			noretr = 1;
337 			break;
338 
339 		case 'O':
340 			noguestretr = 1;
341 			break;
342 
343 		case 'p':
344 			pid_file = optarg;
345 			break;
346 
347 		case 'P':
348 			bindport = optarg;
349 			break;
350 
351 		case 'r':
352 			readonly = 1;
353 			break;
354 
355 		case 'R':
356 			paranoid = 0;
357 			break;
358 
359 		case 'S':
360 			stats++;
361 			break;
362 
363 		case 't':
364 			timeout = atoi(optarg);
365 			if (maxtimeout < timeout)
366 				maxtimeout = timeout;
367 			break;
368 
369 		case 'T':
370 			maxtimeout = atoi(optarg);
371 			if (timeout > maxtimeout)
372 				timeout = maxtimeout;
373 			break;
374 
375 		case 'u':
376 		    {
377 			long val = 0;
378 
379 			val = strtol(optarg, &optarg, 8);
380 			if (*optarg != '\0' || val < 0)
381 				syslog(LOG_WARNING, "bad value for -u");
382 			else
383 				defumask = val;
384 			break;
385 		    }
386 		case 'U':
387 			restricted_data_ports = 0;
388 			break;
389 
390 		case 'v':
391 			ftpdebug++;
392 			break;
393 
394 		case 'W':
395 			dowtmp = 0;
396 			break;
397 
398 		default:
399 			syslog(LOG_WARNING, "unknown flag -%c ignored", optopt);
400 			break;
401 		}
402 	}
403 
404 	if (daemon_mode) {
405 		int *ctl_sock, fd, maxfd = -1, nfds, i;
406 		fd_set defreadfds, readfds;
407 		pid_t pid;
408 		struct pidfh *pfh;
409 
410 		if ((pfh = pidfile_open(pid_file, 0600, &pid)) == NULL) {
411 			if (errno == EEXIST) {
412 				syslog(LOG_ERR, "%s already running, pid %d",
413 				       getprogname(), (int)pid);
414 				exit(1);
415 			}
416 			syslog(LOG_WARNING, "pidfile_open: %m");
417 		}
418 
419 		/*
420 		 * Detach from parent.
421 		 */
422 		if (daemon(1, 1) < 0) {
423 			syslog(LOG_ERR, "failed to become a daemon");
424 			exit(1);
425 		}
426 
427 		if (pfh != NULL && pidfile_write(pfh) == -1)
428 			syslog(LOG_WARNING, "pidfile_write: %m");
429 
430 		sa.sa_handler = reapchild;
431 		sigaction(SIGCHLD, &sa, NULL);
432 
433 #ifdef VIRTUAL_HOSTING
434 		inithosts(family);
435 #endif
436 
437 		/*
438 		 * Open a socket, bind it to the FTP port, and start
439 		 * listening.
440 		 */
441 		ctl_sock = socksetup(family, bindname, bindport);
442 		if (ctl_sock == NULL)
443 			exit(1);
444 
445 		FD_ZERO(&defreadfds);
446 		for (i = 1; i <= *ctl_sock; i++) {
447 			FD_SET(ctl_sock[i], &defreadfds);
448 			if (listen(ctl_sock[i], 32) < 0) {
449 				syslog(LOG_ERR, "control listen: %m");
450 				exit(1);
451 			}
452 			if (maxfd < ctl_sock[i])
453 				maxfd = ctl_sock[i];
454 		}
455 
456 		/*
457 		 * Loop forever accepting connection requests and forking off
458 		 * children to handle them.
459 		 */
460 		while (1) {
461 			FD_COPY(&defreadfds, &readfds);
462 			nfds = select(maxfd + 1, &readfds, NULL, NULL, 0);
463 			if (nfds <= 0) {
464 				if (nfds < 0 && errno != EINTR)
465 					syslog(LOG_WARNING, "select: %m");
466 				continue;
467 			}
468 
469 			pid = -1;
470                         for (i = 1; i <= *ctl_sock; i++)
471 				if (FD_ISSET(ctl_sock[i], &readfds)) {
472 					addrlen = sizeof(his_addr);
473 					fd = accept(ctl_sock[i],
474 					    (struct sockaddr *)&his_addr,
475 					    &addrlen);
476 					if (fd == -1) {
477 						syslog(LOG_WARNING,
478 						       "accept: %m");
479 						continue;
480 					}
481 					switch (pid = fork()) {
482 					case 0:
483 						/* child */
484 						dup2(fd, 0);
485 						dup2(fd, 1);
486 						close(fd);
487 						for (i = 1; i <= *ctl_sock; i++)
488 							close(ctl_sock[i]);
489 						if (pfh != NULL)
490 							pidfile_close(pfh);
491 						goto gotchild;
492 					case -1:
493 						syslog(LOG_WARNING, "fork: %m");
494 						/* FALLTHROUGH */
495 					default:
496 						close(fd);
497 					}
498 				}
499 		}
500 	} else {
501 		addrlen = sizeof(his_addr);
502 		if (getpeername(0, (struct sockaddr *)&his_addr, &addrlen) < 0) {
503 			syslog(LOG_ERR, "getpeername (%s): %m",argv[0]);
504 			exit(1);
505 		}
506 
507 #ifdef VIRTUAL_HOSTING
508 		if (his_addr.su_family == AF_INET6 &&
509 		    IN6_IS_ADDR_V4MAPPED(&his_addr.su_sin6.sin6_addr))
510 			family = AF_INET;
511 		else
512 			family = his_addr.su_family;
513 		inithosts(family);
514 #endif
515 	}
516 
517 gotchild:
518 	sa.sa_handler = SIG_DFL;
519 	sigaction(SIGCHLD, &sa, NULL);
520 
521 	sa.sa_handler = sigurg;
522 	sa.sa_flags = 0;		/* don't restart syscalls for SIGURG */
523 	sigaction(SIGURG, &sa, NULL);
524 
525 	sigfillset(&sa.sa_mask);	/* block all signals in handler */
526 	sa.sa_flags = SA_RESTART;
527 	sa.sa_handler = sigquit;
528 	sigaction(SIGHUP, &sa, NULL);
529 	sigaction(SIGINT, &sa, NULL);
530 	sigaction(SIGQUIT, &sa, NULL);
531 	sigaction(SIGTERM, &sa, NULL);
532 
533 	sa.sa_handler = lostconn;
534 	sigaction(SIGPIPE, &sa, NULL);
535 
536 	addrlen = sizeof(ctrl_addr);
537 	if (getsockname(0, (struct sockaddr *)&ctrl_addr, &addrlen) < 0) {
538 		syslog(LOG_ERR, "getsockname (%s): %m",argv[0]);
539 		exit(1);
540 	}
541 	dataport = ntohs(ctrl_addr.su_port) - 1; /* as per RFC 959 */
542 #ifdef VIRTUAL_HOSTING
543 	/* select our identity from virtual host table */
544 	selecthost(&ctrl_addr);
545 #endif
546 #ifdef IP_TOS
547 	if (ctrl_addr.su_family == AF_INET)
548       {
549 	tos = IPTOS_LOWDELAY;
550 	if (setsockopt(0, IPPROTO_IP, IP_TOS, &tos, sizeof(int)) < 0)
551 		syslog(LOG_WARNING, "control setsockopt (IP_TOS): %m");
552       }
553 #endif
554 	/*
555 	 * Disable Nagle on the control channel so that we don't have to wait
556 	 * for peer's ACK before issuing our next reply.
557 	 */
558 	if (setsockopt(0, IPPROTO_TCP, TCP_NODELAY, &on, sizeof(on)) < 0)
559 		syslog(LOG_WARNING, "control setsockopt (TCP_NODELAY): %m");
560 
561 	data_source.su_port = htons(ntohs(ctrl_addr.su_port) - 1);
562 
563 	/* set this here so klogin can use it... */
564 	snprintf(ttyline, sizeof(ttyline), "ftp%d", getpid());
565 
566 	/* Try to handle urgent data inline */
567 #ifdef SO_OOBINLINE
568 	if (setsockopt(0, SOL_SOCKET, SO_OOBINLINE, &on, sizeof(on)) < 0)
569 		syslog(LOG_WARNING, "control setsockopt (SO_OOBINLINE): %m");
570 #endif
571 
572 #ifdef	F_SETOWN
573 	if (fcntl(fileno(stdin), F_SETOWN, getpid()) == -1)
574 		syslog(LOG_ERR, "fcntl F_SETOWN: %m");
575 #endif
576 	dolog((struct sockaddr *)&his_addr);
577 	/*
578 	 * Set up default state
579 	 */
580 	data = -1;
581 	type = TYPE_A;
582 	form = FORM_N;
583 	stru = STRU_F;
584 	mode = MODE_S;
585 	tmpline[0] = '\0';
586 
587 	/* If logins are disabled, print out the message. */
588 	if ((fd = fopen(_PATH_NOLOGIN,"r")) != NULL) {
589 		while (fgets(line, sizeof(line), fd) != NULL) {
590 			if ((cp = strchr(line, '\n')) != NULL)
591 				*cp = '\0';
592 			lreply(530, "%s", line);
593 		}
594 		fflush(stdout);
595 		fclose(fd);
596 		reply(530, "System not available.");
597 		exit(0);
598 	}
599 #ifdef VIRTUAL_HOSTING
600 	fd = fopen(thishost->welcome, "r");
601 #else
602 	fd = fopen(_PATH_FTPWELCOME, "r");
603 #endif
604 	if (fd != NULL) {
605 		while (fgets(line, sizeof(line), fd) != NULL) {
606 			if ((cp = strchr(line, '\n')) != NULL)
607 				*cp = '\0';
608 			lreply(220, "%s", line);
609 		}
610 		fflush(stdout);
611 		fclose(fd);
612 		/* reply(220,) must follow */
613 	}
614 #ifndef VIRTUAL_HOSTING
615 	if (hostname == NULL) {
616 		if ((hostname = malloc(MAXHOSTNAMELEN)) == NULL)
617 			fatalerror("Ran out of memory.");
618 		if (gethostname(hostname, MAXHOSTNAMELEN - 1) < 0)
619 			hostname[0] = '\0';
620 		hostname[MAXHOSTNAMELEN - 1] = '\0';
621 	}
622 #endif
623 	if (hostinfo)
624 		reply(220, "%s FTP server (%s) ready.", hostname, version);
625 	else
626 		reply(220, "FTP server ready.");
627 	for (;;)
628 		yyparse();
629 	/* NOTREACHED */
630 }
631 
632 static void
633 lostconn(int signo)
634 {
635 
636 	if (ftpdebug)
637 		syslog(LOG_DEBUG, "lost connection");
638 	dologout(1);
639 }
640 
641 static void
642 sigquit(int signo)
643 {
644 
645 	syslog(LOG_ERR, "got signal %d", signo);
646 	dologout(1);
647 }
648 
649 #ifdef VIRTUAL_HOSTING
650 /*
651  * read in virtual host tables (if they exist)
652  */
653 
654 static void
655 inithosts(int family)
656 {
657 	int insert;
658 	size_t len;
659 	FILE *fp;
660 	char *cp, *mp, *line;
661 	char *vhost, *anonuser, *statfile, *welcome, *loginmsg;
662 	struct ftphost *hrp, *lhrp;
663 	struct addrinfo hints, *res, *ai;
664 
665 	/*
666 	 * Fill in the default host information
667 	 */
668 	if (hostname == NULL) {
669 		if ((hostname = malloc(MAXHOSTNAMELEN)) == NULL)
670 			fatalerror("Ran out of memory.");
671 		if (gethostname(hostname, MAXHOSTNAMELEN - 1) < 0)
672 			hostname[0] = '\0';
673 		hostname[MAXHOSTNAMELEN - 1] = '\0';
674 	}
675 	if ((hrp = malloc(sizeof(struct ftphost))) == NULL)
676 		fatalerror("Ran out of memory.");
677 	hrp->hostname = hostname;
678 	hrp->hostinfo = NULL;
679 
680 	memset(&hints, 0, sizeof(hints));
681 	hints.ai_flags = AI_PASSIVE;
682 	hints.ai_family = family;
683 	hints.ai_socktype = SOCK_STREAM;
684 	if (getaddrinfo(hrp->hostname, NULL, &hints, &res) == 0)
685 		hrp->hostinfo = res;
686 	hrp->statfile = _PATH_FTPDSTATFILE;
687 	hrp->welcome  = _PATH_FTPWELCOME;
688 	hrp->loginmsg = _PATH_FTPLOGINMESG;
689 	hrp->anonuser = "ftp";
690 	hrp->next = NULL;
691 	thishost = firsthost = lhrp = hrp;
692 	if ((fp = fopen(_PATH_FTPHOSTS, "r")) != NULL) {
693 		int addrsize, gothost;
694 		void *addr;
695 		struct hostent *hp;
696 
697 		while ((line = fgetln(fp, &len)) != NULL) {
698 			int	i, hp_error;
699 
700 			/* skip comments */
701 			if (line[0] == '#')
702 				continue;
703 			if (line[len - 1] == '\n') {
704 				line[len - 1] = '\0';
705 				mp = NULL;
706 			} else {
707 				if ((mp = malloc(len + 1)) == NULL)
708 					fatalerror("Ran out of memory.");
709 				memcpy(mp, line, len);
710 				mp[len] = '\0';
711 				line = mp;
712 			}
713 			cp = strtok(line, " \t");
714 			/* skip empty lines */
715 			if (cp == NULL)
716 				goto nextline;
717 			vhost = cp;
718 
719 			/* set defaults */
720 			anonuser = "ftp";
721 			statfile = _PATH_FTPDSTATFILE;
722 			welcome  = _PATH_FTPWELCOME;
723 			loginmsg = _PATH_FTPLOGINMESG;
724 
725 			/*
726 			 * Preparse the line so we can use its info
727 			 * for all the addresses associated with
728 			 * the virtual host name.
729 			 * Field 0, the virtual host name, is special:
730 			 * it's already parsed off and will be strdup'ed
731 			 * later, after we know its canonical form.
732 			 */
733 			for (i = 1; i < 5 && (cp = strtok(NULL, " \t")); i++)
734 				if (*cp != '-' && (cp = strdup(cp)))
735 					switch (i) {
736 					case 1:	/* anon user permissions */
737 						anonuser = cp;
738 						break;
739 					case 2: /* statistics file */
740 						statfile = cp;
741 						break;
742 					case 3: /* welcome message */
743 						welcome  = cp;
744 						break;
745 					case 4: /* login message */
746 						loginmsg = cp;
747 						break;
748 					default: /* programming error */
749 						abort();
750 						/* NOTREACHED */
751 					}
752 
753 			hints.ai_flags = AI_PASSIVE;
754 			hints.ai_family = family;
755 			hints.ai_socktype = SOCK_STREAM;
756 			if (getaddrinfo(vhost, NULL, &hints, &res) != 0)
757 				goto nextline;
758 			for (ai = res; ai != NULL && ai->ai_addr != NULL;
759 			     ai = ai->ai_next) {
760 
761 			gothost = 0;
762 			for (hrp = firsthost; hrp != NULL; hrp = hrp->next) {
763 				struct addrinfo *hi;
764 
765 				for (hi = hrp->hostinfo; hi != NULL;
766 				     hi = hi->ai_next)
767 					if (hi->ai_addrlen == ai->ai_addrlen &&
768 					    memcmp(hi->ai_addr,
769 						   ai->ai_addr,
770 						   ai->ai_addr->sa_len) == 0) {
771 						gothost++;
772 						break;
773 					}
774 				if (gothost)
775 					break;
776 			}
777 			if (hrp == NULL) {
778 				if ((hrp = malloc(sizeof(struct ftphost))) == NULL)
779 					goto nextline;
780 				hrp->hostname = NULL;
781 				insert = 1;
782 			} else {
783 				if (hrp->hostinfo && hrp->hostinfo != res)
784 					freeaddrinfo(hrp->hostinfo);
785 				insert = 0; /* host already in the chain */
786 			}
787 			hrp->hostinfo = res;
788 
789 			/*
790 			 * determine hostname to use.
791 			 * force defined name if there is a valid alias
792 			 * otherwise fallback to primary hostname
793 			 */
794 			/* XXX: getaddrinfo() can't do alias check */
795 			switch(hrp->hostinfo->ai_family) {
796 			case AF_INET:
797 				addr = &((struct sockaddr_in *)hrp->hostinfo->ai_addr)->sin_addr;
798 				addrsize = sizeof(struct in_addr);
799 				break;
800 			case AF_INET6:
801 				addr = &((struct sockaddr_in6 *)hrp->hostinfo->ai_addr)->sin6_addr;
802 				addrsize = sizeof(struct in6_addr);
803 				break;
804 			default:
805 				/* should not reach here */
806 				freeaddrinfo(hrp->hostinfo);
807 				if (insert)
808 					free(hrp); /*not in chain, can free*/
809 				else
810 					hrp->hostinfo = NULL; /*mark as blank*/
811 				goto nextline;
812 				/* NOTREACHED */
813 			}
814 			if ((hp = getipnodebyaddr(addr, addrsize,
815 						  hrp->hostinfo->ai_family,
816 						  &hp_error)) != NULL) {
817 				if (strcmp(vhost, hp->h_name) != 0) {
818 					if (hp->h_aliases == NULL)
819 						vhost = hp->h_name;
820 					else {
821 						i = 0;
822 						while (hp->h_aliases[i] &&
823 						       strcmp(vhost, hp->h_aliases[i]) != 0)
824 							++i;
825 						if (hp->h_aliases[i] == NULL)
826 							vhost = hp->h_name;
827 					}
828 				}
829 			}
830 			if (hrp->hostname &&
831 			    strcmp(hrp->hostname, vhost) != 0) {
832 				free(hrp->hostname);
833 				hrp->hostname = NULL;
834 			}
835 			if (hrp->hostname == NULL &&
836 			    (hrp->hostname = strdup(vhost)) == NULL) {
837 				freeaddrinfo(hrp->hostinfo);
838 				hrp->hostinfo = NULL; /* mark as blank */
839 				if (hp)
840 					freehostent(hp);
841 				goto nextline;
842 			}
843 			hrp->anonuser = anonuser;
844 			hrp->statfile = statfile;
845 			hrp->welcome  = welcome;
846 			hrp->loginmsg = loginmsg;
847 			if (insert) {
848 				hrp->next  = NULL;
849 				lhrp->next = hrp;
850 				lhrp = hrp;
851 			}
852 			if (hp)
853 				freehostent(hp);
854 		      }
855 nextline:
856 			if (mp)
857 				free(mp);
858 		}
859 		fclose(fp);
860 	}
861 }
862 
863 static void
864 selecthost(union sockunion *su)
865 {
866 	struct ftphost	*hrp;
867 	u_int16_t port;
868 #ifdef INET6
869 	struct in6_addr *mapped_in6 = NULL;
870 #endif
871 	struct addrinfo *hi;
872 
873 #ifdef INET6
874 	/*
875 	 * XXX IPv4 mapped IPv6 addr consideraton,
876 	 * specified in rfc2373.
877 	 */
878 	if (su->su_family == AF_INET6 &&
879 	    IN6_IS_ADDR_V4MAPPED(&su->su_sin6.sin6_addr))
880 		mapped_in6 = &su->su_sin6.sin6_addr;
881 #endif
882 
883 	hrp = thishost = firsthost;	/* default */
884 	port = su->su_port;
885 	su->su_port = 0;
886 	while (hrp != NULL) {
887 	    for (hi = hrp->hostinfo; hi != NULL; hi = hi->ai_next) {
888 		if (memcmp(su, hi->ai_addr, hi->ai_addrlen) == 0) {
889 			thishost = hrp;
890 			goto found;
891 		}
892 #ifdef INET6
893 		/* XXX IPv4 mapped IPv6 addr consideraton */
894 		if (hi->ai_addr->sa_family == AF_INET && mapped_in6 != NULL &&
895 		    (memcmp(&mapped_in6->s6_addr[12],
896 			    &((struct sockaddr_in *)hi->ai_addr)->sin_addr,
897 			    sizeof(struct in_addr)) == 0)) {
898 			thishost = hrp;
899 			goto found;
900 		}
901 #endif
902 	    }
903 	    hrp = hrp->next;
904 	}
905 found:
906 	su->su_port = port;
907 	/* setup static variables as appropriate */
908 	hostname = thishost->hostname;
909 	ftpuser = thishost->anonuser;
910 }
911 #endif
912 
913 /*
914  * Helper function for sgetpwnam().
915  */
916 static char *
917 sgetsave(char *s)
918 {
919 	char *new = malloc(strlen(s) + 1);
920 
921 	if (new == NULL) {
922 		reply(421, "Ran out of memory.");
923 		dologout(1);
924 		/* NOTREACHED */
925 	}
926 	strcpy(new, s);
927 	return (new);
928 }
929 
930 /*
931  * Save the result of a getpwnam.  Used for USER command, since
932  * the data returned must not be clobbered by any other command
933  * (e.g., globbing).
934  * NB: The data returned by sgetpwnam() will remain valid until
935  * the next call to this function.  Its difference from getpwnam()
936  * is that sgetpwnam() is known to be called from ftpd code only.
937  */
938 static struct passwd *
939 sgetpwnam(char *name)
940 {
941 	static struct passwd save;
942 	struct passwd *p;
943 
944 	if ((p = getpwnam(name)) == NULL)
945 		return (p);
946 	if (save.pw_name) {
947 		free(save.pw_name);
948 		free(save.pw_passwd);
949 		free(save.pw_gecos);
950 		free(save.pw_dir);
951 		free(save.pw_shell);
952 	}
953 	save = *p;
954 	save.pw_name = sgetsave(p->pw_name);
955 	save.pw_passwd = sgetsave(p->pw_passwd);
956 	save.pw_gecos = sgetsave(p->pw_gecos);
957 	save.pw_dir = sgetsave(p->pw_dir);
958 	save.pw_shell = sgetsave(p->pw_shell);
959 	return (&save);
960 }
961 
962 static int login_attempts;	/* number of failed login attempts */
963 static int askpasswd;		/* had user command, ask for passwd */
964 static char curname[MAXLOGNAME];	/* current USER name */
965 
966 /*
967  * USER command.
968  * Sets global passwd pointer pw if named account exists and is acceptable;
969  * sets askpasswd if a PASS command is expected.  If logged in previously,
970  * need to reset state.  If name is "ftp" or "anonymous", the name is not in
971  * _PATH_FTPUSERS, and ftp account exists, set guest and pw, then just return.
972  * If account doesn't exist, ask for passwd anyway.  Otherwise, check user
973  * requesting login privileges.  Disallow anyone who does not have a standard
974  * shell as returned by getusershell().  Disallow anyone mentioned in the file
975  * _PATH_FTPUSERS to allow people such as root and uucp to be avoided.
976  */
977 void
978 user(char *name)
979 {
980 	char *cp, *shell;
981 
982 	if (logged_in) {
983 		if (guest) {
984 			reply(530, "Can't change user from guest login.");
985 			return;
986 		} else if (dochroot) {
987 			reply(530, "Can't change user from chroot user.");
988 			return;
989 		}
990 		end_login();
991 	}
992 
993 	guest = 0;
994 #ifdef VIRTUAL_HOSTING
995 	pw = sgetpwnam(thishost->anonuser);
996 #else
997 	pw = sgetpwnam("ftp");
998 #endif
999 	if (strcmp(name, "ftp") == 0 || strcmp(name, "anonymous") == 0) {
1000 		if (checkuser(_PATH_FTPUSERS, "ftp", 0, NULL) ||
1001 		    checkuser(_PATH_FTPUSERS, "anonymous", 0, NULL))
1002 			reply(530, "User %s access denied.", name);
1003 		else if (pw != NULL) {
1004 			guest = 1;
1005 			askpasswd = 1;
1006 			reply(331,
1007 			"Guest login ok, send your email address as password.");
1008 		} else
1009 			reply(530, "User %s unknown.", name);
1010 		if (!askpasswd && logging)
1011 			syslog(LOG_NOTICE,
1012 			    "ANONYMOUS FTP LOGIN REFUSED FROM %s", remotehost);
1013 		return;
1014 	}
1015 	if (anon_only != 0) {
1016 		reply(530, "Sorry, only anonymous ftp allowed.");
1017 		return;
1018 	}
1019 
1020 	if ((pw = sgetpwnam(name))) {
1021 		if ((shell = pw->pw_shell) == NULL || *shell == 0)
1022 			shell = _PATH_BSHELL;
1023 		setusershell();
1024 		while ((cp = getusershell()) != NULL)
1025 			if (strcmp(cp, shell) == 0)
1026 				break;
1027 		endusershell();
1028 
1029 		if (cp == NULL || checkuser(_PATH_FTPUSERS, name, 1, NULL)) {
1030 			reply(530, "User %s access denied.", name);
1031 			if (logging)
1032 				syslog(LOG_NOTICE,
1033 				    "FTP LOGIN REFUSED FROM %s, %s",
1034 				    remotehost, name);
1035 			pw = NULL;
1036 			return;
1037 		}
1038 	}
1039 	if (logging)
1040 		strncpy(curname, name, sizeof(curname)-1);
1041 
1042 	pwok = 0;
1043 #ifdef USE_PAM
1044 	/* XXX Kluge! The conversation mechanism needs to be fixed. */
1045 #endif
1046 	if (opiechallenge(&opiedata, name, opieprompt) == 0) {
1047 		pwok = (pw != NULL) &&
1048 		       opieaccessfile(remotehost) &&
1049 		       opiealways(pw->pw_dir);
1050 		reply(331, "Response to %s %s for %s.",
1051 		      opieprompt, pwok ? "requested" : "required", name);
1052 	} else {
1053 		pwok = 1;
1054 		reply(331, "Password required for %s.", name);
1055 	}
1056 	askpasswd = 1;
1057 	/*
1058 	 * Delay before reading passwd after first failed
1059 	 * attempt to slow down passwd-guessing programs.
1060 	 */
1061 	if (login_attempts)
1062 		sleep(login_attempts);
1063 }
1064 
1065 /*
1066  * Check if a user is in the file "fname",
1067  * return a pointer to a malloc'd string with the rest
1068  * of the matching line in "residue" if not NULL.
1069  */
1070 static int
1071 checkuser(char *fname, char *name, int pwset, char **residue)
1072 {
1073 	FILE *fd;
1074 	int found = 0;
1075 	size_t len;
1076 	char *line, *mp, *p;
1077 
1078 	if ((fd = fopen(fname, "r")) != NULL) {
1079 		while (!found && (line = fgetln(fd, &len)) != NULL) {
1080 			/* skip comments */
1081 			if (line[0] == '#')
1082 				continue;
1083 			if (line[len - 1] == '\n') {
1084 				line[len - 1] = '\0';
1085 				mp = NULL;
1086 			} else {
1087 				if ((mp = malloc(len + 1)) == NULL)
1088 					fatalerror("Ran out of memory.");
1089 				memcpy(mp, line, len);
1090 				mp[len] = '\0';
1091 				line = mp;
1092 			}
1093 			/* avoid possible leading and trailing whitespace */
1094 			p = strtok(line, " \t");
1095 			/* skip empty lines */
1096 			if (p == NULL)
1097 				goto nextline;
1098 			/*
1099 			 * if first chr is '@', check group membership
1100 			 */
1101 			if (p[0] == '@') {
1102 				int i = 0;
1103 				struct group *grp;
1104 
1105 				if (p[1] == '\0') /* single @ matches anyone */
1106 					found = 1;
1107 				else {
1108 					if ((grp = getgrnam(p+1)) == NULL)
1109 						goto nextline;
1110 					/*
1111 					 * Check user's default group
1112 					 */
1113 					if (pwset && grp->gr_gid == pw->pw_gid)
1114 						found = 1;
1115 					/*
1116 					 * Check supplementary groups
1117 					 */
1118 					while (!found && grp->gr_mem[i])
1119 						found = strcmp(name,
1120 							grp->gr_mem[i++])
1121 							== 0;
1122 				}
1123 			}
1124 			/*
1125 			 * Otherwise, just check for username match
1126 			 */
1127 			else
1128 				found = strcmp(p, name) == 0;
1129 			/*
1130 			 * Save the rest of line to "residue" if matched
1131 			 */
1132 			if (found && residue) {
1133 				if ((p = strtok(NULL, "")) != NULL)
1134 					p += strspn(p, " \t");
1135 				if (p && *p) {
1136 				 	if ((*residue = strdup(p)) == NULL)
1137 						fatalerror("Ran out of memory.");
1138 				} else
1139 					*residue = NULL;
1140 			}
1141 nextline:
1142 			if (mp)
1143 				free(mp);
1144 		}
1145 		fclose(fd);
1146 	}
1147 	return (found);
1148 }
1149 
1150 /*
1151  * Terminate login as previous user, if any, resetting state;
1152  * used when USER command is given or login fails.
1153  */
1154 static void
1155 end_login(void)
1156 {
1157 #ifdef USE_PAM
1158 	int e;
1159 #endif
1160 
1161 	seteuid(0);
1162 	if (logged_in && dowtmp)
1163 		ftpd_logwtmp(ttyline, "", NULL);
1164 	pw = NULL;
1165 #ifdef	LOGIN_CAP
1166 	/* XXX Missing LOGIN_SETMAC */
1167 	setusercontext(NULL, getpwuid(0), 0,
1168 		       LOGIN_SETPRIORITY|LOGIN_SETRESOURCES|LOGIN_SETUMASK);
1169 #endif
1170 #ifdef USE_PAM
1171 	if (pamh) {
1172 		if ((e = pam_setcred(pamh, PAM_DELETE_CRED)) != PAM_SUCCESS)
1173 			syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, e));
1174 		if ((e = pam_close_session(pamh,0)) != PAM_SUCCESS)
1175 			syslog(LOG_ERR, "pam_close_session: %s", pam_strerror(pamh, e));
1176 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS)
1177 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1178 		pamh = NULL;
1179 	}
1180 #endif
1181 	logged_in = 0;
1182 	guest = 0;
1183 	dochroot = 0;
1184 }
1185 
1186 #ifdef USE_PAM
1187 
1188 /*
1189  * the following code is stolen from imap-uw PAM authentication module and
1190  * login.c
1191  */
1192 #define COPY_STRING(s) (s ? strdup(s) : NULL)
1193 
1194 struct cred_t {
1195 	const char *uname;		/* user name */
1196 	const char *pass;		/* password */
1197 };
1198 typedef struct cred_t cred_t;
1199 
1200 static int
1201 auth_conv(int num_msg, const struct pam_message **msg,
1202 	  struct pam_response **resp, void *appdata)
1203 {
1204 	int i;
1205 	cred_t *cred = (cred_t *) appdata;
1206 	struct pam_response *reply;
1207 
1208 	reply = calloc(num_msg, sizeof *reply);
1209 	if (reply == NULL)
1210 		return PAM_BUF_ERR;
1211 
1212 	for (i = 0; i < num_msg; i++) {
1213 		switch (msg[i]->msg_style) {
1214 		case PAM_PROMPT_ECHO_ON:	/* assume want user name */
1215 			reply[i].resp_retcode = PAM_SUCCESS;
1216 			reply[i].resp = COPY_STRING(cred->uname);
1217 			/* PAM frees resp. */
1218 			break;
1219 		case PAM_PROMPT_ECHO_OFF:	/* assume want password */
1220 			reply[i].resp_retcode = PAM_SUCCESS;
1221 			reply[i].resp = COPY_STRING(cred->pass);
1222 			/* PAM frees resp. */
1223 			break;
1224 		case PAM_TEXT_INFO:
1225 		case PAM_ERROR_MSG:
1226 			reply[i].resp_retcode = PAM_SUCCESS;
1227 			reply[i].resp = NULL;
1228 			break;
1229 		default:			/* unknown message style */
1230 			free(reply);
1231 			return PAM_CONV_ERR;
1232 		}
1233 	}
1234 
1235 	*resp = reply;
1236 	return PAM_SUCCESS;
1237 }
1238 
1239 /*
1240  * Attempt to authenticate the user using PAM.  Returns 0 if the user is
1241  * authenticated, or 1 if not authenticated.  If some sort of PAM system
1242  * error occurs (e.g., the "/etc/pam.conf" file is missing) then this
1243  * function returns -1.  This can be used as an indication that we should
1244  * fall back to a different authentication mechanism.
1245  */
1246 static int
1247 auth_pam(struct passwd **ppw, const char *pass)
1248 {
1249 	const char *tmpl_user;
1250 	const void *item;
1251 	int rval;
1252 	int e;
1253 	cred_t auth_cred = { (*ppw)->pw_name, pass };
1254 	struct pam_conv conv = { &auth_conv, &auth_cred };
1255 
1256 	e = pam_start("ftpd", (*ppw)->pw_name, &conv, &pamh);
1257 	if (e != PAM_SUCCESS) {
1258 		/*
1259 		 * In OpenPAM, it's OK to pass NULL to pam_strerror()
1260 		 * if context creation has failed in the first place.
1261 		 */
1262 		syslog(LOG_ERR, "pam_start: %s", pam_strerror(NULL, e));
1263 		return -1;
1264 	}
1265 
1266 	e = pam_set_item(pamh, PAM_RHOST, remotehost);
1267 	if (e != PAM_SUCCESS) {
1268 		syslog(LOG_ERR, "pam_set_item(PAM_RHOST): %s",
1269 			pam_strerror(pamh, e));
1270 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
1271 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1272 		}
1273 		pamh = NULL;
1274 		return -1;
1275 	}
1276 
1277 	e = pam_authenticate(pamh, 0);
1278 	switch (e) {
1279 	case PAM_SUCCESS:
1280 		/*
1281 		 * With PAM we support the concept of a "template"
1282 		 * user.  The user enters a login name which is
1283 		 * authenticated by PAM, usually via a remote service
1284 		 * such as RADIUS or TACACS+.  If authentication
1285 		 * succeeds, a different but related "template" name
1286 		 * is used for setting the credentials, shell, and
1287 		 * home directory.  The name the user enters need only
1288 		 * exist on the remote authentication server, but the
1289 		 * template name must be present in the local password
1290 		 * database.
1291 		 *
1292 		 * This is supported by two various mechanisms in the
1293 		 * individual modules.  However, from the application's
1294 		 * point of view, the template user is always passed
1295 		 * back as a changed value of the PAM_USER item.
1296 		 */
1297 		if ((e = pam_get_item(pamh, PAM_USER, &item)) ==
1298 		    PAM_SUCCESS) {
1299 			tmpl_user = (const char *) item;
1300 			if (strcmp((*ppw)->pw_name, tmpl_user) != 0)
1301 				*ppw = getpwnam(tmpl_user);
1302 		} else
1303 			syslog(LOG_ERR, "Couldn't get PAM_USER: %s",
1304 			    pam_strerror(pamh, e));
1305 		rval = 0;
1306 		break;
1307 
1308 	case PAM_AUTH_ERR:
1309 	case PAM_USER_UNKNOWN:
1310 	case PAM_MAXTRIES:
1311 		rval = 1;
1312 		break;
1313 
1314 	default:
1315 		syslog(LOG_ERR, "pam_authenticate: %s", pam_strerror(pamh, e));
1316 		rval = -1;
1317 		break;
1318 	}
1319 
1320 	if (rval == 0) {
1321 		e = pam_acct_mgmt(pamh, 0);
1322 		if (e != PAM_SUCCESS) {
1323 			syslog(LOG_ERR, "pam_acct_mgmt: %s",
1324 						pam_strerror(pamh, e));
1325 			rval = 1;
1326 		}
1327 	}
1328 
1329 	if (rval != 0) {
1330 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
1331 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1332 		}
1333 		pamh = NULL;
1334 	}
1335 	return rval;
1336 }
1337 
1338 #endif /* USE_PAM */
1339 
1340 void
1341 pass(char *passwd)
1342 {
1343 	int rval;
1344 	FILE *fd;
1345 #ifdef	LOGIN_CAP
1346 	login_cap_t *lc = NULL;
1347 #endif
1348 #ifdef USE_PAM
1349 	int e;
1350 #endif
1351 	char *residue = NULL;
1352 	char *xpasswd;
1353 
1354 	if (logged_in || askpasswd == 0) {
1355 		reply(503, "Login with USER first.");
1356 		return;
1357 	}
1358 	askpasswd = 0;
1359 	if (!guest) {		/* "ftp" is only account allowed no password */
1360 		if (pw == NULL) {
1361 			rval = 1;	/* failure below */
1362 			goto skip;
1363 		}
1364 #ifdef USE_PAM
1365 		rval = auth_pam(&pw, passwd);
1366 		if (rval >= 0) {
1367 			opieunlock();
1368 			goto skip;
1369 		}
1370 #endif
1371 		if (opieverify(&opiedata, passwd) == 0)
1372 			xpasswd = pw->pw_passwd;
1373 		else if (pwok) {
1374 			xpasswd = crypt(passwd, pw->pw_passwd);
1375 			if (passwd[0] == '\0' && pw->pw_passwd[0] != '\0')
1376 				xpasswd = ":";
1377 		} else {
1378 			rval = 1;
1379 			goto skip;
1380 		}
1381 		rval = strcmp(pw->pw_passwd, xpasswd);
1382 		if (pw->pw_expire && time(NULL) >= pw->pw_expire)
1383 			rval = 1;	/* failure */
1384 skip:
1385 		/*
1386 		 * If rval == 1, the user failed the authentication check
1387 		 * above.  If rval == 0, either PAM or local authentication
1388 		 * succeeded.
1389 		 */
1390 		if (rval) {
1391 			reply(530, "Login incorrect.");
1392 			if (logging) {
1393 				syslog(LOG_NOTICE,
1394 				    "FTP LOGIN FAILED FROM %s",
1395 				    remotehost);
1396 				syslog(LOG_AUTHPRIV | LOG_NOTICE,
1397 				    "FTP LOGIN FAILED FROM %s, %s",
1398 				    remotehost, curname);
1399 			}
1400 			pw = NULL;
1401 			if (login_attempts++ >= 5) {
1402 				syslog(LOG_NOTICE,
1403 				    "repeated login failures from %s",
1404 				    remotehost);
1405 				exit(0);
1406 			}
1407 			return;
1408 		}
1409 	}
1410 	login_attempts = 0;		/* this time successful */
1411 	if (setegid(pw->pw_gid) < 0) {
1412 		reply(550, "Can't set gid.");
1413 		return;
1414 	}
1415 	/* May be overridden by login.conf */
1416 	umask(defumask);
1417 #ifdef	LOGIN_CAP
1418 	if ((lc = login_getpwclass(pw)) != NULL) {
1419 		char	remote_ip[NI_MAXHOST];
1420 
1421 		if (getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
1422 			remote_ip, sizeof(remote_ip) - 1, NULL, 0,
1423 			NI_NUMERICHOST))
1424 				*remote_ip = 0;
1425 		remote_ip[sizeof(remote_ip) - 1] = 0;
1426 		if (!auth_hostok(lc, remotehost, remote_ip)) {
1427 			syslog(LOG_INFO|LOG_AUTH,
1428 			    "FTP LOGIN FAILED (HOST) as %s: permission denied.",
1429 			    pw->pw_name);
1430 			reply(530, "Permission denied.");
1431 			pw = NULL;
1432 			return;
1433 		}
1434 		if (!auth_timeok(lc, time(NULL))) {
1435 			reply(530, "Login not available right now.");
1436 			pw = NULL;
1437 			return;
1438 		}
1439 	}
1440 	/* XXX Missing LOGIN_SETMAC */
1441 	setusercontext(lc, pw, 0,
1442 		LOGIN_SETLOGIN|LOGIN_SETGROUP|LOGIN_SETPRIORITY|
1443 		LOGIN_SETRESOURCES|LOGIN_SETUMASK);
1444 #else
1445 	setlogin(pw->pw_name);
1446 	initgroups(pw->pw_name, pw->pw_gid);
1447 #endif
1448 
1449 #ifdef USE_PAM
1450 	if (pamh) {
1451 		if ((e = pam_open_session(pamh, 0)) != PAM_SUCCESS) {
1452 			syslog(LOG_ERR, "pam_open_session: %s", pam_strerror(pamh, e));
1453 		} else if ((e = pam_setcred(pamh, PAM_ESTABLISH_CRED)) != PAM_SUCCESS) {
1454 			syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, e));
1455 		}
1456 	}
1457 #endif
1458 
1459 	/* open wtmp before chroot */
1460 	if (dowtmp)
1461 		ftpd_logwtmp(ttyline, pw->pw_name,
1462 		    (struct sockaddr *)&his_addr);
1463 	logged_in = 1;
1464 
1465 	if (guest && stats && statfd < 0)
1466 #ifdef VIRTUAL_HOSTING
1467 		statfd = open(thishost->statfile, O_WRONLY|O_APPEND);
1468 #else
1469 		statfd = open(_PATH_FTPDSTATFILE, O_WRONLY|O_APPEND);
1470 #endif
1471 		if (statfd < 0)
1472 			stats = 0;
1473 
1474 	dochroot =
1475 		checkuser(_PATH_FTPCHROOT, pw->pw_name, 1, &residue)
1476 #ifdef	LOGIN_CAP	/* Allow login.conf configuration as well */
1477 		|| login_getcapbool(lc, "ftp-chroot", 0)
1478 #endif
1479 	;
1480 	chrootdir = NULL;
1481 	/*
1482 	 * For a chrooted local user,
1483 	 * a) see whether ftpchroot(5) specifies a chroot directory,
1484 	 * b) extract the directory pathname from the line,
1485 	 * c) expand it to the absolute pathname if necessary.
1486 	 */
1487 	if (dochroot && residue &&
1488 	    (chrootdir = strtok(residue, " \t")) != NULL) {
1489 		if (chrootdir[0] != '/')
1490 			asprintf(&chrootdir, "%s/%s", pw->pw_dir, chrootdir);
1491 		else
1492 			chrootdir = strdup(chrootdir); /* make it permanent */
1493 		if (chrootdir == NULL)
1494 			fatalerror("Ran out of memory.");
1495 	}
1496 	if (guest || dochroot) {
1497 		/*
1498 		 * If no chroot directory set yet, use the login directory.
1499 		 * Copy it so it can be modified while pw->pw_dir stays intact.
1500 		 */
1501 		if (chrootdir == NULL &&
1502 		    (chrootdir = strdup(pw->pw_dir)) == NULL)
1503 			fatalerror("Ran out of memory.");
1504 		/*
1505 		 * Check for the "/chroot/./home" syntax,
1506 		 * separate the chroot and home directory pathnames.
1507 		 */
1508 		if ((homedir = strstr(chrootdir, "/./")) != NULL) {
1509 			*(homedir++) = '\0';	/* wipe '/' */
1510 			homedir++;		/* skip '.' */
1511 		} else {
1512 			/*
1513 			 * We MUST do a chdir() after the chroot. Otherwise
1514 			 * the old current directory will be accessible as "."
1515 			 * outside the new root!
1516 			 */
1517 			homedir = "/";
1518 		}
1519 		/*
1520 		 * Finally, do chroot()
1521 		 */
1522 		if (chroot(chrootdir) < 0) {
1523 			reply(550, "Can't change root.");
1524 			goto bad;
1525 		}
1526 	} else	/* real user w/o chroot */
1527 		homedir = pw->pw_dir;
1528 	/*
1529 	 * Set euid *before* doing chdir() so
1530 	 * a) the user won't be carried to a directory that he couldn't reach
1531 	 *    on his own due to no permission to upper path components,
1532 	 * b) NFS mounted homedirs w/restrictive permissions will be accessible
1533 	 *    (uid 0 has no root power over NFS if not mapped explicitly.)
1534 	 */
1535 	if (seteuid(pw->pw_uid) < 0) {
1536 		reply(550, "Can't set uid.");
1537 		goto bad;
1538 	}
1539 	if (chdir(homedir) < 0) {
1540 		if (guest || dochroot) {
1541 			reply(550, "Can't change to base directory.");
1542 			goto bad;
1543 		} else {
1544 			if (chdir("/") < 0) {
1545 				reply(550, "Root is inaccessible.");
1546 				goto bad;
1547 			}
1548 			lreply(230, "No directory! Logging in with home=/.");
1549 		}
1550 	}
1551 
1552 	/*
1553 	 * Display a login message, if it exists.
1554 	 * N.B. reply(230,) must follow the message.
1555 	 */
1556 #ifdef VIRTUAL_HOSTING
1557 	fd = fopen(thishost->loginmsg, "r");
1558 #else
1559 	fd = fopen(_PATH_FTPLOGINMESG, "r");
1560 #endif
1561 	if (fd != NULL) {
1562 		char *cp, line[LINE_MAX];
1563 
1564 		while (fgets(line, sizeof(line), fd) != NULL) {
1565 			if ((cp = strchr(line, '\n')) != NULL)
1566 				*cp = '\0';
1567 			lreply(230, "%s", line);
1568 		}
1569 		fflush(stdout);
1570 		fclose(fd);
1571 	}
1572 	if (guest) {
1573 		if (ident != NULL)
1574 			free(ident);
1575 		ident = strdup(passwd);
1576 		if (ident == NULL)
1577 			fatalerror("Ran out of memory.");
1578 
1579 		reply(230, "Guest login ok, access restrictions apply.");
1580 #ifdef SETPROCTITLE
1581 #ifdef VIRTUAL_HOSTING
1582 		if (thishost != firsthost)
1583 			snprintf(proctitle, sizeof(proctitle),
1584 				 "%s: anonymous(%s)/%s", remotehost, hostname,
1585 				 passwd);
1586 		else
1587 #endif
1588 			snprintf(proctitle, sizeof(proctitle),
1589 				 "%s: anonymous/%s", remotehost, passwd);
1590 		setproctitle("%s", proctitle);
1591 #endif /* SETPROCTITLE */
1592 		if (logging)
1593 			syslog(LOG_INFO, "ANONYMOUS FTP LOGIN FROM %s, %s",
1594 			    remotehost, passwd);
1595 	} else {
1596 		if (dochroot)
1597 			reply(230, "User %s logged in, "
1598 				   "access restrictions apply.", pw->pw_name);
1599 		else
1600 			reply(230, "User %s logged in.", pw->pw_name);
1601 
1602 #ifdef SETPROCTITLE
1603 		snprintf(proctitle, sizeof(proctitle),
1604 			 "%s: user/%s", remotehost, pw->pw_name);
1605 		setproctitle("%s", proctitle);
1606 #endif /* SETPROCTITLE */
1607 		if (logging)
1608 			syslog(LOG_INFO, "FTP LOGIN FROM %s as %s",
1609 			    remotehost, pw->pw_name);
1610 	}
1611 	if (logging && (guest || dochroot))
1612 		syslog(LOG_INFO, "session root changed to %s", chrootdir);
1613 #ifdef	LOGIN_CAP
1614 	login_close(lc);
1615 #endif
1616 	if (residue)
1617 		free(residue);
1618 	return;
1619 bad:
1620 	/* Forget all about it... */
1621 #ifdef	LOGIN_CAP
1622 	login_close(lc);
1623 #endif
1624 	if (residue)
1625 		free(residue);
1626 	end_login();
1627 }
1628 
1629 void
1630 retrieve(char *cmd, char *name)
1631 {
1632 	FILE *fin, *dout;
1633 	struct stat st;
1634 	int (*closefunc)(FILE *);
1635 	time_t start;
1636 
1637 	if (cmd == NULL) {
1638 		fin = fopen(name, "r"), closefunc = fclose;
1639 		st.st_size = 0;
1640 	} else {
1641 		char line[BUFSIZ];
1642 
1643 		snprintf(line, sizeof(line), cmd, name), name = line;
1644 		fin = ftpd_popen(line, "r"), closefunc = ftpd_pclose;
1645 		st.st_size = -1;
1646 		st.st_blksize = BUFSIZ;
1647 	}
1648 	if (fin == NULL) {
1649 		if (errno != 0) {
1650 			perror_reply(550, name);
1651 			if (cmd == NULL) {
1652 				LOGCMD("get", name);
1653 			}
1654 		}
1655 		return;
1656 	}
1657 	byte_count = -1;
1658 	if (cmd == NULL) {
1659 		if (fstat(fileno(fin), &st) < 0) {
1660 			perror_reply(550, name);
1661 			goto done;
1662 		}
1663 		if (!S_ISREG(st.st_mode)) {
1664 			/*
1665 			 * Never sending a raw directory is a workaround
1666 			 * for buggy clients that will attempt to RETR
1667 			 * a directory before listing it, e.g., Mozilla.
1668 			 * Preventing a guest from getting irregular files
1669 			 * is a simple security measure.
1670 			 */
1671 			if (S_ISDIR(st.st_mode) || guest) {
1672 				reply(550, "%s: not a plain file.", name);
1673 				goto done;
1674 			}
1675 			st.st_size = -1;
1676 			/* st.st_blksize is set for all descriptor types */
1677 		}
1678 	}
1679 	if (restart_point) {
1680 		if (type == TYPE_A) {
1681 			off_t i, n;
1682 			int c;
1683 
1684 			n = restart_point;
1685 			i = 0;
1686 			while (i++ < n) {
1687 				if ((c=getc(fin)) == EOF) {
1688 					perror_reply(550, name);
1689 					goto done;
1690 				}
1691 				if (c == '\n')
1692 					i++;
1693 			}
1694 		} else if (lseek(fileno(fin), restart_point, L_SET) < 0) {
1695 			perror_reply(550, name);
1696 			goto done;
1697 		}
1698 	}
1699 	dout = dataconn(name, st.st_size, "w");
1700 	if (dout == NULL)
1701 		goto done;
1702 	time(&start);
1703 	send_data(fin, dout, st.st_blksize, st.st_size,
1704 		  restart_point == 0 && cmd == NULL && S_ISREG(st.st_mode));
1705 	if (cmd == NULL && guest && stats && byte_count > 0)
1706 		logxfer(name, byte_count, start);
1707 	fclose(dout);
1708 	data = -1;
1709 	pdata = -1;
1710 done:
1711 	if (cmd == NULL)
1712 		LOGBYTES("get", name, byte_count);
1713 	(*closefunc)(fin);
1714 }
1715 
1716 void
1717 store(char *name, char *mode, int unique)
1718 {
1719 	int fd;
1720 	FILE *fout, *din;
1721 	int (*closefunc)(FILE *);
1722 
1723 	if (*mode == 'a') {		/* APPE */
1724 		if (unique) {
1725 			/* Programming error */
1726 			syslog(LOG_ERR, "Internal: unique flag to APPE");
1727 			unique = 0;
1728 		}
1729 		if (guest && noguestmod) {
1730 			reply(550, "Appending to existing file denied.");
1731 			goto err;
1732 		}
1733 		restart_point = 0;	/* not affected by preceding REST */
1734 	}
1735 	if (unique)			/* STOU overrides REST */
1736 		restart_point = 0;
1737 	if (guest && noguestmod) {
1738 		if (restart_point) {	/* guest STOR w/REST */
1739 			reply(550, "Modifying existing file denied.");
1740 			goto err;
1741 		} else			/* treat guest STOR as STOU */
1742 			unique = 1;
1743 	}
1744 
1745 	if (restart_point)
1746 		mode = "r+";	/* so ASCII manual seek can work */
1747 	if (unique) {
1748 		if ((fd = guniquefd(name, &name)) < 0)
1749 			goto err;
1750 		fout = fdopen(fd, mode);
1751 	} else
1752 		fout = fopen(name, mode);
1753 	closefunc = fclose;
1754 	if (fout == NULL) {
1755 		perror_reply(553, name);
1756 		goto err;
1757 	}
1758 	byte_count = -1;
1759 	if (restart_point) {
1760 		if (type == TYPE_A) {
1761 			off_t i, n;
1762 			int c;
1763 
1764 			n = restart_point;
1765 			i = 0;
1766 			while (i++ < n) {
1767 				if ((c=getc(fout)) == EOF) {
1768 					perror_reply(550, name);
1769 					goto done;
1770 				}
1771 				if (c == '\n')
1772 					i++;
1773 			}
1774 			/*
1775 			 * We must do this seek to "current" position
1776 			 * because we are changing from reading to
1777 			 * writing.
1778 			 */
1779 			if (fseeko(fout, 0, SEEK_CUR) < 0) {
1780 				perror_reply(550, name);
1781 				goto done;
1782 			}
1783 		} else if (lseek(fileno(fout), restart_point, L_SET) < 0) {
1784 			perror_reply(550, name);
1785 			goto done;
1786 		}
1787 	}
1788 	din = dataconn(name, -1, "r");
1789 	if (din == NULL)
1790 		goto done;
1791 	if (receive_data(din, fout) == 0) {
1792 		if (unique)
1793 			reply(226, "Transfer complete (unique file name:%s).",
1794 			    name);
1795 		else
1796 			reply(226, "Transfer complete.");
1797 	}
1798 	fclose(din);
1799 	data = -1;
1800 	pdata = -1;
1801 done:
1802 	LOGBYTES(*mode == 'a' ? "append" : "put", name, byte_count);
1803 	(*closefunc)(fout);
1804 	return;
1805 err:
1806 	LOGCMD(*mode == 'a' ? "append" : "put" , name);
1807 	return;
1808 }
1809 
1810 static FILE *
1811 getdatasock(char *mode)
1812 {
1813 	int on = 1, s, t, tries;
1814 
1815 	if (data >= 0)
1816 		return (fdopen(data, mode));
1817 
1818 	s = socket(data_dest.su_family, SOCK_STREAM, 0);
1819 	if (s < 0)
1820 		goto bad;
1821 	if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
1822 		syslog(LOG_WARNING, "data setsockopt (SO_REUSEADDR): %m");
1823 	/* anchor socket to avoid multi-homing problems */
1824 	data_source = ctrl_addr;
1825 	data_source.su_port = htons(dataport);
1826 	seteuid(0);
1827 	for (tries = 1; ; tries++) {
1828 		/*
1829 		 * We should loop here since it's possible that
1830 		 * another ftpd instance has passed this point and is
1831 		 * trying to open a data connection in active mode now.
1832 		 * Until the other connection is opened, we'll be getting
1833 		 * EADDRINUSE because no SOCK_STREAM sockets in the system
1834 		 * can share both local and remote addresses, localIP:20
1835 		 * and *:* in this case.
1836 		 */
1837 		if (bind(s, (struct sockaddr *)&data_source,
1838 		    data_source.su_len) >= 0)
1839 			break;
1840 		if (errno != EADDRINUSE || tries > 10)
1841 			goto bad;
1842 		sleep(tries);
1843 	}
1844 	seteuid(pw->pw_uid);
1845 #ifdef IP_TOS
1846 	if (data_source.su_family == AF_INET)
1847       {
1848 	on = IPTOS_THROUGHPUT;
1849 	if (setsockopt(s, IPPROTO_IP, IP_TOS, &on, sizeof(int)) < 0)
1850 		syslog(LOG_WARNING, "data setsockopt (IP_TOS): %m");
1851       }
1852 #endif
1853 #ifdef TCP_NOPUSH
1854 	/*
1855 	 * Turn off push flag to keep sender TCP from sending short packets
1856 	 * at the boundaries of each write().
1857 	 */
1858 	on = 1;
1859 	if (setsockopt(s, IPPROTO_TCP, TCP_NOPUSH, &on, sizeof on) < 0)
1860 		syslog(LOG_WARNING, "data setsockopt (TCP_NOPUSH): %m");
1861 #endif
1862 	return (fdopen(s, mode));
1863 bad:
1864 	/* Return the real value of errno (close may change it) */
1865 	t = errno;
1866 	seteuid(pw->pw_uid);
1867 	close(s);
1868 	errno = t;
1869 	return (NULL);
1870 }
1871 
1872 static FILE *
1873 dataconn(char *name, off_t size, char *mode)
1874 {
1875 	char sizebuf[32];
1876 	FILE *file;
1877 	int retry = 0, tos, conerrno;
1878 
1879 	file_size = size;
1880 	byte_count = 0;
1881 	if (size != -1)
1882 		snprintf(sizebuf, sizeof(sizebuf),
1883 				" (%jd bytes)", (intmax_t)size);
1884 	else
1885 		*sizebuf = '\0';
1886 	if (pdata >= 0) {
1887 		union sockunion from;
1888 		socklen_t fromlen = ctrl_addr.su_len;
1889 		int flags, s;
1890 		struct timeval timeout;
1891 		fd_set set;
1892 
1893 		FD_ZERO(&set);
1894 		FD_SET(pdata, &set);
1895 
1896 		timeout.tv_usec = 0;
1897 		timeout.tv_sec = 120;
1898 
1899 		/*
1900 		 * Granted a socket is in the blocking I/O mode,
1901 		 * accept() will block after a successful select()
1902 		 * if the selected connection dies in between.
1903 		 * Therefore set the non-blocking I/O flag here.
1904 		 */
1905 		if ((flags = fcntl(pdata, F_GETFL, 0)) == -1 ||
1906 		    fcntl(pdata, F_SETFL, flags | O_NONBLOCK) == -1)
1907 			goto pdata_err;
1908 		if (select(pdata+1, &set, NULL, NULL, &timeout) <= 0 ||
1909 		    (s = accept(pdata, (struct sockaddr *) &from, &fromlen)) < 0)
1910 			goto pdata_err;
1911 		close(pdata);
1912 		pdata = s;
1913 		/*
1914 		 * Unset the inherited non-blocking I/O flag
1915 		 * on the child socket so stdio can work on it.
1916 		 */
1917 		if ((flags = fcntl(pdata, F_GETFL, 0)) == -1 ||
1918 		    fcntl(pdata, F_SETFL, flags & ~O_NONBLOCK) == -1)
1919 			goto pdata_err;
1920 #ifdef IP_TOS
1921 		if (from.su_family == AF_INET)
1922 	      {
1923 		tos = IPTOS_THROUGHPUT;
1924 		if (setsockopt(s, IPPROTO_IP, IP_TOS, &tos, sizeof(int)) < 0)
1925 			syslog(LOG_WARNING, "pdata setsockopt (IP_TOS): %m");
1926 	      }
1927 #endif
1928 		reply(150, "Opening %s mode data connection for '%s'%s.",
1929 		     type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
1930 		return (fdopen(pdata, mode));
1931 pdata_err:
1932 		reply(425, "Can't open data connection.");
1933 		close(pdata);
1934 		pdata = -1;
1935 		return (NULL);
1936 	}
1937 	if (data >= 0) {
1938 		reply(125, "Using existing data connection for '%s'%s.",
1939 		    name, sizebuf);
1940 		usedefault = 1;
1941 		return (fdopen(data, mode));
1942 	}
1943 	if (usedefault)
1944 		data_dest = his_addr;
1945 	usedefault = 1;
1946 	do {
1947 		file = getdatasock(mode);
1948 		if (file == NULL) {
1949 			char hostbuf[NI_MAXHOST], portbuf[NI_MAXSERV];
1950 
1951 			if (getnameinfo((struct sockaddr *)&data_source,
1952 				data_source.su_len,
1953 				hostbuf, sizeof(hostbuf) - 1,
1954 				portbuf, sizeof(portbuf) - 1,
1955 				NI_NUMERICHOST|NI_NUMERICSERV))
1956 					*hostbuf = *portbuf = 0;
1957 			hostbuf[sizeof(hostbuf) - 1] = 0;
1958 			portbuf[sizeof(portbuf) - 1] = 0;
1959 			reply(425, "Can't create data socket (%s,%s): %s.",
1960 				hostbuf, portbuf, strerror(errno));
1961 			return (NULL);
1962 		}
1963 		data = fileno(file);
1964 		conerrno = 0;
1965 		if (connect(data, (struct sockaddr *)&data_dest,
1966 		    data_dest.su_len) == 0)
1967 			break;
1968 		conerrno = errno;
1969 		fclose(file);
1970 		data = -1;
1971 		if (conerrno == EADDRINUSE) {
1972 			sleep(swaitint);
1973 			retry += swaitint;
1974 		} else {
1975 			break;
1976 		}
1977 	} while (retry <= swaitmax);
1978 	if (conerrno != 0) {
1979 		reply(425, "Can't build data connection: %s.",
1980 			   strerror(conerrno));
1981 		return (NULL);
1982 	}
1983 	reply(150, "Opening %s mode data connection for '%s'%s.",
1984 	     type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
1985 	return (file);
1986 }
1987 
1988 /*
1989  * A helper macro to avoid code duplication
1990  * in send_data() and receive_data().
1991  *
1992  * XXX We have to block SIGURG during putc() because BSD stdio
1993  * is unable to restart interrupted write operations and hence
1994  * the entire buffer contents will be lost as soon as a write()
1995  * call indicates EINTR to stdio.
1996  */
1997 #define FTPD_PUTC(ch, file, label)					\
1998 	do {								\
1999 		int ret;						\
2000 									\
2001 		do {							\
2002 			START_UNSAFE;					\
2003 			ret = putc((ch), (file));			\
2004 			END_UNSAFE;					\
2005 			CHECKOOB(return (-1))				\
2006 			else if (ferror(file))				\
2007 				goto label;				\
2008 			clearerr(file);					\
2009 		} while (ret == EOF);					\
2010 	} while (0)
2011 
2012 /*
2013  * Tranfer the contents of "instr" to "outstr" peer using the appropriate
2014  * encapsulation of the data subject to Mode, Structure, and Type.
2015  *
2016  * NB: Form isn't handled.
2017  */
2018 static int
2019 send_data(FILE *instr, FILE *outstr, size_t blksize, off_t filesize, int isreg)
2020 {
2021 	int c, cp, filefd, netfd;
2022 	char *buf;
2023 
2024 	STARTXFER;
2025 
2026 	switch (type) {
2027 
2028 	case TYPE_A:
2029 		cp = EOF;
2030 		for (;;) {
2031 			c = getc(instr);
2032 			CHECKOOB(return (-1))
2033 			else if (c == EOF && ferror(instr))
2034 				goto file_err;
2035 			if (c == EOF) {
2036 				if (ferror(instr)) {	/* resume after OOB */
2037 					clearerr(instr);
2038 					continue;
2039 				}
2040 				if (feof(instr))	/* EOF */
2041 					break;
2042 				syslog(LOG_ERR, "Internal: impossible condition"
2043 						" on file after getc()");
2044 				goto file_err;
2045 			}
2046 			if (c == '\n' && cp != '\r') {
2047 				FTPD_PUTC('\r', outstr, data_err);
2048 				byte_count++;
2049 			}
2050 			FTPD_PUTC(c, outstr, data_err);
2051 			byte_count++;
2052 			cp = c;
2053 		}
2054 #ifdef notyet	/* BSD stdio isn't ready for that */
2055 		while (fflush(outstr) == EOF) {
2056 			CHECKOOB(return (-1))
2057 			else
2058 				goto data_err;
2059 			clearerr(outstr);
2060 		}
2061 		ENDXFER;
2062 #else
2063 		ENDXFER;
2064 		if (fflush(outstr) == EOF)
2065 			goto data_err;
2066 #endif
2067 		reply(226, "Transfer complete.");
2068 		return (0);
2069 
2070 	case TYPE_I:
2071 	case TYPE_L:
2072 		/*
2073 		 * isreg is only set if we are not doing restart and we
2074 		 * are sending a regular file
2075 		 */
2076 		netfd = fileno(outstr);
2077 		filefd = fileno(instr);
2078 
2079 		if (isreg) {
2080 			char *msg = "Transfer complete.";
2081 			off_t cnt, offset;
2082 			int err;
2083 
2084 			cnt = offset = 0;
2085 
2086 			while (filesize > 0) {
2087 				err = sendfile(filefd, netfd, offset, 0,
2088 					       NULL, &cnt, 0);
2089 				/*
2090 				 * Calculate byte_count before OOB processing.
2091 				 * It can be used in myoob() later.
2092 				 */
2093 				byte_count += cnt;
2094 				offset += cnt;
2095 				filesize -= cnt;
2096 				CHECKOOB(return (-1))
2097 				else if (err == -1) {
2098 					if (errno != EINTR &&
2099 					    cnt == 0 && offset == 0)
2100 						goto oldway;
2101 					goto data_err;
2102 				}
2103 				if (err == -1)	/* resume after OOB */
2104 					continue;
2105 				/*
2106 				 * We hit the EOF prematurely.
2107 				 * Perhaps the file was externally truncated.
2108 				 */
2109 				if (cnt == 0) {
2110 					msg = "Transfer finished due to "
2111 					      "premature end of file.";
2112 					break;
2113 				}
2114 			}
2115 			ENDXFER;
2116 			reply(226, msg);
2117 			return (0);
2118 		}
2119 
2120 oldway:
2121 		if ((buf = malloc(blksize)) == NULL) {
2122 			ENDXFER;
2123 			reply(451, "Ran out of memory.");
2124 			return (-1);
2125 		}
2126 
2127 		for (;;) {
2128 			int cnt, len;
2129 			char *bp;
2130 
2131 			cnt = read(filefd, buf, blksize);
2132 			CHECKOOB(free(buf); return (-1))
2133 			else if (cnt < 0) {
2134 				free(buf);
2135 				goto file_err;
2136 			}
2137 			if (cnt < 0)	/* resume after OOB */
2138 				continue;
2139 			if (cnt == 0)	/* EOF */
2140 				break;
2141 			for (len = cnt, bp = buf; len > 0;) {
2142 				cnt = write(netfd, bp, len);
2143 				CHECKOOB(free(buf); return (-1))
2144 				else if (cnt < 0) {
2145 					free(buf);
2146 					goto data_err;
2147 				}
2148 				if (cnt <= 0)
2149 					continue;
2150 				len -= cnt;
2151 				bp += cnt;
2152 				byte_count += cnt;
2153 			}
2154 		}
2155 		ENDXFER;
2156 		free(buf);
2157 		reply(226, "Transfer complete.");
2158 		return (0);
2159 	default:
2160 		ENDXFER;
2161 		reply(550, "Unimplemented TYPE %d in send_data.", type);
2162 		return (-1);
2163 	}
2164 
2165 data_err:
2166 	ENDXFER;
2167 	perror_reply(426, "Data connection");
2168 	return (-1);
2169 
2170 file_err:
2171 	ENDXFER;
2172 	perror_reply(551, "Error on input file");
2173 	return (-1);
2174 }
2175 
2176 /*
2177  * Transfer data from peer to "outstr" using the appropriate encapulation of
2178  * the data subject to Mode, Structure, and Type.
2179  *
2180  * N.B.: Form isn't handled.
2181  */
2182 static int
2183 receive_data(FILE *instr, FILE *outstr)
2184 {
2185 	int c, cp;
2186 	int bare_lfs = 0;
2187 
2188 	STARTXFER;
2189 
2190 	switch (type) {
2191 
2192 	case TYPE_I:
2193 	case TYPE_L:
2194 		for (;;) {
2195 			int cnt, len;
2196 			char *bp;
2197 			char buf[BUFSIZ];
2198 
2199 			cnt = read(fileno(instr), buf, sizeof(buf));
2200 			CHECKOOB(return (-1))
2201 			else if (cnt < 0)
2202 				goto data_err;
2203 			if (cnt < 0)	/* resume after OOB */
2204 				continue;
2205 			if (cnt == 0)	/* EOF */
2206 				break;
2207 			for (len = cnt, bp = buf; len > 0;) {
2208 				cnt = write(fileno(outstr), bp, len);
2209 				CHECKOOB(return (-1))
2210 				else if (cnt < 0)
2211 					goto file_err;
2212 				if (cnt <= 0)
2213 					continue;
2214 				len -= cnt;
2215 				bp += cnt;
2216 				byte_count += cnt;
2217 			}
2218 		}
2219 		ENDXFER;
2220 		return (0);
2221 
2222 	case TYPE_E:
2223 		ENDXFER;
2224 		reply(553, "TYPE E not implemented.");
2225 		return (-1);
2226 
2227 	case TYPE_A:
2228 		cp = EOF;
2229 		for (;;) {
2230 			c = getc(instr);
2231 			CHECKOOB(return (-1))
2232 			else if (c == EOF && ferror(instr))
2233 				goto data_err;
2234 			if (c == EOF && ferror(instr)) { /* resume after OOB */
2235 				clearerr(instr);
2236 				continue;
2237 			}
2238 
2239 			if (cp == '\r') {
2240 				if (c != '\n')
2241 					FTPD_PUTC('\r', outstr, file_err);
2242 			} else
2243 				if (c == '\n')
2244 					bare_lfs++;
2245 			if (c == '\r') {
2246 				byte_count++;
2247 				cp = c;
2248 				continue;
2249 			}
2250 
2251 			/* Check for EOF here in order not to lose last \r. */
2252 			if (c == EOF) {
2253 				if (feof(instr))	/* EOF */
2254 					break;
2255 				syslog(LOG_ERR, "Internal: impossible condition"
2256 						" on data stream after getc()");
2257 				goto data_err;
2258 			}
2259 
2260 			byte_count++;
2261 			FTPD_PUTC(c, outstr, file_err);
2262 			cp = c;
2263 		}
2264 #ifdef notyet	/* BSD stdio isn't ready for that */
2265 		while (fflush(outstr) == EOF) {
2266 			CHECKOOB(return (-1))
2267 			else
2268 				goto file_err;
2269 			clearerr(outstr);
2270 		}
2271 		ENDXFER;
2272 #else
2273 		ENDXFER;
2274 		if (fflush(outstr) == EOF)
2275 			goto file_err;
2276 #endif
2277 		if (bare_lfs) {
2278 			lreply(226,
2279 		"WARNING! %d bare linefeeds received in ASCII mode.",
2280 			    bare_lfs);
2281 		printf("   File may not have transferred correctly.\r\n");
2282 		}
2283 		return (0);
2284 	default:
2285 		ENDXFER;
2286 		reply(550, "Unimplemented TYPE %d in receive_data.", type);
2287 		return (-1);
2288 	}
2289 
2290 data_err:
2291 	ENDXFER;
2292 	perror_reply(426, "Data connection");
2293 	return (-1);
2294 
2295 file_err:
2296 	ENDXFER;
2297 	perror_reply(452, "Error writing to file");
2298 	return (-1);
2299 }
2300 
2301 void
2302 statfilecmd(char *filename)
2303 {
2304 	FILE *fin;
2305 	int atstart;
2306 	int c, code;
2307 	char line[LINE_MAX];
2308 	struct stat st;
2309 
2310 	code = lstat(filename, &st) == 0 && S_ISDIR(st.st_mode) ? 212 : 213;
2311 	snprintf(line, sizeof(line), _PATH_LS " -lgA %s", filename);
2312 	fin = ftpd_popen(line, "r");
2313 	lreply(code, "Status of %s:", filename);
2314 	atstart = 1;
2315 	while ((c = getc(fin)) != EOF) {
2316 		if (c == '\n') {
2317 			if (ferror(stdout)){
2318 				perror_reply(421, "Control connection");
2319 				ftpd_pclose(fin);
2320 				dologout(1);
2321 				/* NOTREACHED */
2322 			}
2323 			if (ferror(fin)) {
2324 				perror_reply(551, filename);
2325 				ftpd_pclose(fin);
2326 				return;
2327 			}
2328 			putc('\r', stdout);
2329 		}
2330 		/*
2331 		 * RFC 959 says neutral text should be prepended before
2332 		 * a leading 3-digit number followed by whitespace, but
2333 		 * many ftp clients can be confused by any leading digits,
2334 		 * as a matter of fact.
2335 		 */
2336 		if (atstart && isdigit(c))
2337 			putc(' ', stdout);
2338 		putc(c, stdout);
2339 		atstart = (c == '\n');
2340 	}
2341 	ftpd_pclose(fin);
2342 	reply(code, "End of status.");
2343 }
2344 
2345 void
2346 statcmd(void)
2347 {
2348 	union sockunion *su;
2349 	u_char *a, *p;
2350 	char hname[NI_MAXHOST];
2351 	int ispassive;
2352 
2353 	if (hostinfo) {
2354 		lreply(211, "%s FTP server status:", hostname);
2355 		printf("     %s\r\n", version);
2356 	} else
2357 		lreply(211, "FTP server status:");
2358 	printf("     Connected to %s", remotehost);
2359 	if (!getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
2360 			 hname, sizeof(hname) - 1, NULL, 0, NI_NUMERICHOST)) {
2361 		hname[sizeof(hname) - 1] = 0;
2362 		if (strcmp(hname, remotehost) != 0)
2363 			printf(" (%s)", hname);
2364 	}
2365 	printf("\r\n");
2366 	if (logged_in) {
2367 		if (guest)
2368 			printf("     Logged in anonymously\r\n");
2369 		else
2370 			printf("     Logged in as %s\r\n", pw->pw_name);
2371 	} else if (askpasswd)
2372 		printf("     Waiting for password\r\n");
2373 	else
2374 		printf("     Waiting for user name\r\n");
2375 	printf("     TYPE: %s", typenames[type]);
2376 	if (type == TYPE_A || type == TYPE_E)
2377 		printf(", FORM: %s", formnames[form]);
2378 	if (type == TYPE_L)
2379 #if CHAR_BIT == 8
2380 		printf(" %d", CHAR_BIT);
2381 #else
2382 		printf(" %d", bytesize);	/* need definition! */
2383 #endif
2384 	printf("; STRUcture: %s; transfer MODE: %s\r\n",
2385 	    strunames[stru], modenames[mode]);
2386 	if (data != -1)
2387 		printf("     Data connection open\r\n");
2388 	else if (pdata != -1) {
2389 		ispassive = 1;
2390 		su = &pasv_addr;
2391 		goto printaddr;
2392 	} else if (usedefault == 0) {
2393 		ispassive = 0;
2394 		su = &data_dest;
2395 printaddr:
2396 #define UC(b) (((int) b) & 0xff)
2397 		if (epsvall) {
2398 			printf("     EPSV only mode (EPSV ALL)\r\n");
2399 			goto epsvonly;
2400 		}
2401 
2402 		/* PORT/PASV */
2403 		if (su->su_family == AF_INET) {
2404 			a = (u_char *) &su->su_sin.sin_addr;
2405 			p = (u_char *) &su->su_sin.sin_port;
2406 			printf("     %s (%d,%d,%d,%d,%d,%d)\r\n",
2407 				ispassive ? "PASV" : "PORT",
2408 				UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
2409 				UC(p[0]), UC(p[1]));
2410 		}
2411 
2412 		/* LPRT/LPSV */
2413 	    {
2414 		int alen, af, i;
2415 
2416 		switch (su->su_family) {
2417 		case AF_INET:
2418 			a = (u_char *) &su->su_sin.sin_addr;
2419 			p = (u_char *) &su->su_sin.sin_port;
2420 			alen = sizeof(su->su_sin.sin_addr);
2421 			af = 4;
2422 			break;
2423 		case AF_INET6:
2424 			a = (u_char *) &su->su_sin6.sin6_addr;
2425 			p = (u_char *) &su->su_sin6.sin6_port;
2426 			alen = sizeof(su->su_sin6.sin6_addr);
2427 			af = 6;
2428 			break;
2429 		default:
2430 			af = 0;
2431 			break;
2432 		}
2433 		if (af) {
2434 			printf("     %s (%d,%d,", ispassive ? "LPSV" : "LPRT",
2435 				af, alen);
2436 			for (i = 0; i < alen; i++)
2437 				printf("%d,", UC(a[i]));
2438 			printf("%d,%d,%d)\r\n", 2, UC(p[0]), UC(p[1]));
2439 		}
2440 	    }
2441 
2442 epsvonly:;
2443 		/* EPRT/EPSV */
2444 	    {
2445 		int af;
2446 
2447 		switch (su->su_family) {
2448 		case AF_INET:
2449 			af = 1;
2450 			break;
2451 		case AF_INET6:
2452 			af = 2;
2453 			break;
2454 		default:
2455 			af = 0;
2456 			break;
2457 		}
2458 		if (af) {
2459 			union sockunion tmp;
2460 
2461 			tmp = *su;
2462 			if (tmp.su_family == AF_INET6)
2463 				tmp.su_sin6.sin6_scope_id = 0;
2464 			if (!getnameinfo((struct sockaddr *)&tmp, tmp.su_len,
2465 					hname, sizeof(hname) - 1, NULL, 0,
2466 					NI_NUMERICHOST)) {
2467 				hname[sizeof(hname) - 1] = 0;
2468 				printf("     %s |%d|%s|%d|\r\n",
2469 					ispassive ? "EPSV" : "EPRT",
2470 					af, hname, htons(tmp.su_port));
2471 			}
2472 		}
2473 	    }
2474 #undef UC
2475 	} else
2476 		printf("     No data connection\r\n");
2477 	reply(211, "End of status.");
2478 }
2479 
2480 void
2481 fatalerror(char *s)
2482 {
2483 
2484 	reply(451, "Error in server: %s", s);
2485 	reply(221, "Closing connection due to server error.");
2486 	dologout(0);
2487 	/* NOTREACHED */
2488 }
2489 
2490 void
2491 reply(int n, const char *fmt, ...)
2492 {
2493 	va_list ap;
2494 
2495 	printf("%d ", n);
2496 	va_start(ap, fmt);
2497 	vprintf(fmt, ap);
2498 	va_end(ap);
2499 	printf("\r\n");
2500 	fflush(stdout);
2501 	if (ftpdebug) {
2502 		syslog(LOG_DEBUG, "<--- %d ", n);
2503 		va_start(ap, fmt);
2504 		vsyslog(LOG_DEBUG, fmt, ap);
2505 		va_end(ap);
2506 	}
2507 }
2508 
2509 void
2510 lreply(int n, const char *fmt, ...)
2511 {
2512 	va_list ap;
2513 
2514 	printf("%d- ", n);
2515 	va_start(ap, fmt);
2516 	vprintf(fmt, ap);
2517 	va_end(ap);
2518 	printf("\r\n");
2519 	fflush(stdout);
2520 	if (ftpdebug) {
2521 		syslog(LOG_DEBUG, "<--- %d- ", n);
2522 		va_start(ap, fmt);
2523 		vsyslog(LOG_DEBUG, fmt, ap);
2524 		va_end(ap);
2525 	}
2526 }
2527 
2528 static void
2529 ack(char *s)
2530 {
2531 
2532 	reply(250, "%s command successful.", s);
2533 }
2534 
2535 void
2536 nack(char *s)
2537 {
2538 
2539 	reply(502, "%s command not implemented.", s);
2540 }
2541 
2542 /* ARGSUSED */
2543 void
2544 yyerror(char *s)
2545 {
2546 	char *cp;
2547 
2548 	if ((cp = strchr(cbuf,'\n')))
2549 		*cp = '\0';
2550 	reply(500, "%s: command not understood.", cbuf);
2551 }
2552 
2553 void
2554 delete(char *name)
2555 {
2556 	struct stat st;
2557 
2558 	LOGCMD("delete", name);
2559 	if (lstat(name, &st) < 0) {
2560 		perror_reply(550, name);
2561 		return;
2562 	}
2563 	if (S_ISDIR(st.st_mode)) {
2564 		if (rmdir(name) < 0) {
2565 			perror_reply(550, name);
2566 			return;
2567 		}
2568 		goto done;
2569 	}
2570 	if (guest && noguestmod) {
2571 		reply(550, "Operation not permitted.");
2572 		return;
2573 	}
2574 	if (unlink(name) < 0) {
2575 		perror_reply(550, name);
2576 		return;
2577 	}
2578 done:
2579 	ack("DELE");
2580 }
2581 
2582 void
2583 cwd(char *path)
2584 {
2585 
2586 	if (chdir(path) < 0)
2587 		perror_reply(550, path);
2588 	else
2589 		ack("CWD");
2590 }
2591 
2592 void
2593 makedir(char *name)
2594 {
2595 	char *s;
2596 
2597 	LOGCMD("mkdir", name);
2598 	if (guest && noguestmkd)
2599 		reply(550, "Operation not permitted.");
2600 	else if (mkdir(name, 0777) < 0)
2601 		perror_reply(550, name);
2602 	else {
2603 		if ((s = doublequote(name)) == NULL)
2604 			fatalerror("Ran out of memory.");
2605 		reply(257, "\"%s\" directory created.", s);
2606 		free(s);
2607 	}
2608 }
2609 
2610 void
2611 removedir(char *name)
2612 {
2613 
2614 	LOGCMD("rmdir", name);
2615 	if (rmdir(name) < 0)
2616 		perror_reply(550, name);
2617 	else
2618 		ack("RMD");
2619 }
2620 
2621 void
2622 pwd(void)
2623 {
2624 	char *s, path[MAXPATHLEN + 1];
2625 
2626 	if (getcwd(path, sizeof(path)) == NULL)
2627 		perror_reply(550, "Get current directory");
2628 	else {
2629 		if ((s = doublequote(path)) == NULL)
2630 			fatalerror("Ran out of memory.");
2631 		reply(257, "\"%s\" is current directory.", s);
2632 		free(s);
2633 	}
2634 }
2635 
2636 char *
2637 renamefrom(char *name)
2638 {
2639 	struct stat st;
2640 
2641 	if (guest && noguestmod) {
2642 		reply(550, "Operation not permitted.");
2643 		return (NULL);
2644 	}
2645 	if (lstat(name, &st) < 0) {
2646 		perror_reply(550, name);
2647 		return (NULL);
2648 	}
2649 	reply(350, "File exists, ready for destination name.");
2650 	return (name);
2651 }
2652 
2653 void
2654 renamecmd(char *from, char *to)
2655 {
2656 	struct stat st;
2657 
2658 	LOGCMD2("rename", from, to);
2659 
2660 	if (guest && (stat(to, &st) == 0)) {
2661 		reply(550, "%s: permission denied.", to);
2662 		return;
2663 	}
2664 
2665 	if (rename(from, to) < 0)
2666 		perror_reply(550, "rename");
2667 	else
2668 		ack("RNTO");
2669 }
2670 
2671 static void
2672 dolog(struct sockaddr *who)
2673 {
2674 	char who_name[NI_MAXHOST];
2675 
2676 	realhostname_sa(remotehost, sizeof(remotehost) - 1, who, who->sa_len);
2677 	remotehost[sizeof(remotehost) - 1] = 0;
2678 	if (getnameinfo(who, who->sa_len,
2679 		who_name, sizeof(who_name) - 1, NULL, 0, NI_NUMERICHOST))
2680 			*who_name = 0;
2681 	who_name[sizeof(who_name) - 1] = 0;
2682 
2683 #ifdef SETPROCTITLE
2684 #ifdef VIRTUAL_HOSTING
2685 	if (thishost != firsthost)
2686 		snprintf(proctitle, sizeof(proctitle), "%s: connected (to %s)",
2687 			 remotehost, hostname);
2688 	else
2689 #endif
2690 		snprintf(proctitle, sizeof(proctitle), "%s: connected",
2691 			 remotehost);
2692 	setproctitle("%s", proctitle);
2693 #endif /* SETPROCTITLE */
2694 
2695 	if (logging) {
2696 #ifdef VIRTUAL_HOSTING
2697 		if (thishost != firsthost)
2698 			syslog(LOG_INFO, "connection from %s (%s) to %s",
2699 			       remotehost, who_name, hostname);
2700 		else
2701 #endif
2702 			syslog(LOG_INFO, "connection from %s (%s)",
2703 			       remotehost, who_name);
2704 	}
2705 }
2706 
2707 /*
2708  * Record logout in wtmp file
2709  * and exit with supplied status.
2710  */
2711 void
2712 dologout(int status)
2713 {
2714 
2715 	if (logged_in && dowtmp) {
2716 		seteuid(0);
2717 		ftpd_logwtmp(ttyline, "", NULL);
2718 	}
2719 	/* beware of flushing buffers after a SIGPIPE */
2720 	_exit(status);
2721 }
2722 
2723 static void
2724 sigurg(int signo)
2725 {
2726 
2727 	recvurg = 1;
2728 }
2729 
2730 static void
2731 maskurg(int flag)
2732 {
2733 	int oerrno;
2734 	sigset_t sset;
2735 
2736 	if (!transflag) {
2737 		syslog(LOG_ERR, "Internal: maskurg() while no transfer");
2738 		return;
2739 	}
2740 	oerrno = errno;
2741 	sigemptyset(&sset);
2742 	sigaddset(&sset, SIGURG);
2743 	sigprocmask(flag ? SIG_BLOCK : SIG_UNBLOCK, &sset, NULL);
2744 	errno = oerrno;
2745 }
2746 
2747 static void
2748 flagxfer(int flag)
2749 {
2750 
2751 	if (flag) {
2752 		if (transflag)
2753 			syslog(LOG_ERR, "Internal: flagxfer(1): "
2754 					"transfer already under way");
2755 		transflag = 1;
2756 		maskurg(0);
2757 		recvurg = 0;
2758 	} else {
2759 		if (!transflag)
2760 			syslog(LOG_ERR, "Internal: flagxfer(0): "
2761 					"no active transfer");
2762 		maskurg(1);
2763 		transflag = 0;
2764 	}
2765 }
2766 
2767 /*
2768  * Returns 0 if OK to resume or -1 if abort requested.
2769  */
2770 static int
2771 myoob(void)
2772 {
2773 	char *cp;
2774 	int ret;
2775 
2776 	if (!transflag) {
2777 		syslog(LOG_ERR, "Internal: myoob() while no transfer");
2778 		return (0);
2779 	}
2780 	cp = tmpline;
2781 	ret = getline(cp, 7, stdin);
2782 	if (ret == -1) {
2783 		reply(221, "You could at least say goodbye.");
2784 		dologout(0);
2785 	} else if (ret == -2) {
2786 		/* Ignore truncated command. */
2787 		return (0);
2788 	}
2789 	upper(cp);
2790 	if (strcmp(cp, "ABOR\r\n") == 0) {
2791 		tmpline[0] = '\0';
2792 		reply(426, "Transfer aborted. Data connection closed.");
2793 		reply(226, "Abort successful.");
2794 		return (-1);
2795 	}
2796 	if (strcmp(cp, "STAT\r\n") == 0) {
2797 		tmpline[0] = '\0';
2798 		if (file_size != -1)
2799 			reply(213, "Status: %jd of %jd bytes transferred.",
2800 				   (intmax_t)byte_count, (intmax_t)file_size);
2801 		else
2802 			reply(213, "Status: %jd bytes transferred.",
2803 				   (intmax_t)byte_count);
2804 	}
2805 	return (0);
2806 }
2807 
2808 /*
2809  * Note: a response of 425 is not mentioned as a possible response to
2810  *	the PASV command in RFC959. However, it has been blessed as
2811  *	a legitimate response by Jon Postel in a telephone conversation
2812  *	with Rick Adams on 25 Jan 89.
2813  */
2814 void
2815 passive(void)
2816 {
2817 	socklen_t len;
2818 	int on;
2819 	char *p, *a;
2820 
2821 	if (pdata >= 0)		/* close old port if one set */
2822 		close(pdata);
2823 
2824 	pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
2825 	if (pdata < 0) {
2826 		perror_reply(425, "Can't open passive connection");
2827 		return;
2828 	}
2829 	on = 1;
2830 	if (setsockopt(pdata, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
2831 		syslog(LOG_WARNING, "pdata setsockopt (SO_REUSEADDR): %m");
2832 
2833 	seteuid(0);
2834 
2835 #ifdef IP_PORTRANGE
2836 	if (ctrl_addr.su_family == AF_INET) {
2837 	    on = restricted_data_ports ? IP_PORTRANGE_HIGH
2838 				       : IP_PORTRANGE_DEFAULT;
2839 
2840 	    if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE,
2841 			    &on, sizeof(on)) < 0)
2842 		    goto pasv_error;
2843 	}
2844 #endif
2845 #ifdef IPV6_PORTRANGE
2846 	if (ctrl_addr.su_family == AF_INET6) {
2847 	    on = restricted_data_ports ? IPV6_PORTRANGE_HIGH
2848 				       : IPV6_PORTRANGE_DEFAULT;
2849 
2850 	    if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE,
2851 			    &on, sizeof(on)) < 0)
2852 		    goto pasv_error;
2853 	}
2854 #endif
2855 
2856 	pasv_addr = ctrl_addr;
2857 	pasv_addr.su_port = 0;
2858 	if (bind(pdata, (struct sockaddr *)&pasv_addr, pasv_addr.su_len) < 0)
2859 		goto pasv_error;
2860 
2861 	seteuid(pw->pw_uid);
2862 
2863 	len = sizeof(pasv_addr);
2864 	if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0)
2865 		goto pasv_error;
2866 	if (listen(pdata, 1) < 0)
2867 		goto pasv_error;
2868 	if (pasv_addr.su_family == AF_INET)
2869 		a = (char *) &pasv_addr.su_sin.sin_addr;
2870 	else if (pasv_addr.su_family == AF_INET6 &&
2871 		 IN6_IS_ADDR_V4MAPPED(&pasv_addr.su_sin6.sin6_addr))
2872 		a = (char *) &pasv_addr.su_sin6.sin6_addr.s6_addr[12];
2873 	else
2874 		goto pasv_error;
2875 
2876 	p = (char *) &pasv_addr.su_port;
2877 
2878 #define UC(b) (((int) b) & 0xff)
2879 
2880 	reply(227, "Entering Passive Mode (%d,%d,%d,%d,%d,%d)", UC(a[0]),
2881 		UC(a[1]), UC(a[2]), UC(a[3]), UC(p[0]), UC(p[1]));
2882 	return;
2883 
2884 pasv_error:
2885 	seteuid(pw->pw_uid);
2886 	close(pdata);
2887 	pdata = -1;
2888 	perror_reply(425, "Can't open passive connection");
2889 	return;
2890 }
2891 
2892 /*
2893  * Long Passive defined in RFC 1639.
2894  *     228 Entering Long Passive Mode
2895  *         (af, hal, h1, h2, h3,..., pal, p1, p2...)
2896  */
2897 
2898 void
2899 long_passive(char *cmd, int pf)
2900 {
2901 	socklen_t len;
2902 	int on;
2903 	char *p, *a;
2904 
2905 	if (pdata >= 0)		/* close old port if one set */
2906 		close(pdata);
2907 
2908 	if (pf != PF_UNSPEC) {
2909 		if (ctrl_addr.su_family != pf) {
2910 			switch (ctrl_addr.su_family) {
2911 			case AF_INET:
2912 				pf = 1;
2913 				break;
2914 			case AF_INET6:
2915 				pf = 2;
2916 				break;
2917 			default:
2918 				pf = 0;
2919 				break;
2920 			}
2921 			/*
2922 			 * XXX
2923 			 * only EPRT/EPSV ready clients will understand this
2924 			 */
2925 			if (strcmp(cmd, "EPSV") == 0 && pf) {
2926 				reply(522, "Network protocol mismatch, "
2927 					"use (%d)", pf);
2928 			} else
2929 				reply(501, "Network protocol mismatch."); /*XXX*/
2930 
2931 			return;
2932 		}
2933 	}
2934 
2935 	pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
2936 	if (pdata < 0) {
2937 		perror_reply(425, "Can't open passive connection");
2938 		return;
2939 	}
2940 	on = 1;
2941 	if (setsockopt(pdata, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
2942 		syslog(LOG_WARNING, "pdata setsockopt (SO_REUSEADDR): %m");
2943 
2944 	seteuid(0);
2945 
2946 	pasv_addr = ctrl_addr;
2947 	pasv_addr.su_port = 0;
2948 	len = pasv_addr.su_len;
2949 
2950 #ifdef IP_PORTRANGE
2951 	if (ctrl_addr.su_family == AF_INET) {
2952 	    on = restricted_data_ports ? IP_PORTRANGE_HIGH
2953 				       : IP_PORTRANGE_DEFAULT;
2954 
2955 	    if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE,
2956 			    &on, sizeof(on)) < 0)
2957 		    goto pasv_error;
2958 	}
2959 #endif
2960 #ifdef IPV6_PORTRANGE
2961 	if (ctrl_addr.su_family == AF_INET6) {
2962 	    on = restricted_data_ports ? IPV6_PORTRANGE_HIGH
2963 				       : IPV6_PORTRANGE_DEFAULT;
2964 
2965 	    if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE,
2966 			    &on, sizeof(on)) < 0)
2967 		    goto pasv_error;
2968 	}
2969 #endif
2970 
2971 	if (bind(pdata, (struct sockaddr *)&pasv_addr, len) < 0)
2972 		goto pasv_error;
2973 
2974 	seteuid(pw->pw_uid);
2975 
2976 	if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0)
2977 		goto pasv_error;
2978 	if (listen(pdata, 1) < 0)
2979 		goto pasv_error;
2980 
2981 #define UC(b) (((int) b) & 0xff)
2982 
2983 	if (strcmp(cmd, "LPSV") == 0) {
2984 		p = (char *)&pasv_addr.su_port;
2985 		switch (pasv_addr.su_family) {
2986 		case AF_INET:
2987 			a = (char *) &pasv_addr.su_sin.sin_addr;
2988 		v4_reply:
2989 			reply(228,
2990 "Entering Long Passive Mode (%d,%d,%d,%d,%d,%d,%d,%d,%d)",
2991 			      4, 4, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
2992 			      2, UC(p[0]), UC(p[1]));
2993 			return;
2994 		case AF_INET6:
2995 			if (IN6_IS_ADDR_V4MAPPED(&pasv_addr.su_sin6.sin6_addr)) {
2996 				a = (char *) &pasv_addr.su_sin6.sin6_addr.s6_addr[12];
2997 				goto v4_reply;
2998 			}
2999 			a = (char *) &pasv_addr.su_sin6.sin6_addr;
3000 			reply(228,
3001 "Entering Long Passive Mode "
3002 "(%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d)",
3003 			      6, 16, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
3004 			      UC(a[4]), UC(a[5]), UC(a[6]), UC(a[7]),
3005 			      UC(a[8]), UC(a[9]), UC(a[10]), UC(a[11]),
3006 			      UC(a[12]), UC(a[13]), UC(a[14]), UC(a[15]),
3007 			      2, UC(p[0]), UC(p[1]));
3008 			return;
3009 		}
3010 	} else if (strcmp(cmd, "EPSV") == 0) {
3011 		switch (pasv_addr.su_family) {
3012 		case AF_INET:
3013 		case AF_INET6:
3014 			reply(229, "Entering Extended Passive Mode (|||%d|)",
3015 				ntohs(pasv_addr.su_port));
3016 			return;
3017 		}
3018 	} else {
3019 		/* more proper error code? */
3020 	}
3021 
3022 pasv_error:
3023 	seteuid(pw->pw_uid);
3024 	close(pdata);
3025 	pdata = -1;
3026 	perror_reply(425, "Can't open passive connection");
3027 	return;
3028 }
3029 
3030 /*
3031  * Generate unique name for file with basename "local"
3032  * and open the file in order to avoid possible races.
3033  * Try "local" first, then "local.1", "local.2" etc, up to "local.99".
3034  * Return descriptor to the file, set "name" to its name.
3035  *
3036  * Generates failure reply on error.
3037  */
3038 static int
3039 guniquefd(char *local, char **name)
3040 {
3041 	static char new[MAXPATHLEN];
3042 	struct stat st;
3043 	char *cp;
3044 	int count;
3045 	int fd;
3046 
3047 	cp = strrchr(local, '/');
3048 	if (cp)
3049 		*cp = '\0';
3050 	if (stat(cp ? local : ".", &st) < 0) {
3051 		perror_reply(553, cp ? local : ".");
3052 		return (-1);
3053 	}
3054 	if (cp) {
3055 		/*
3056 		 * Let not overwrite dirname with counter suffix.
3057 		 * -4 is for /nn\0
3058 		 * In this extreme case dot won't be put in front of suffix.
3059 		 */
3060 		if (strlen(local) > sizeof(new) - 4) {
3061 			reply(553, "Pathname too long.");
3062 			return (-1);
3063 		}
3064 		*cp = '/';
3065 	}
3066 	/* -4 is for the .nn<null> we put on the end below */
3067 	snprintf(new, sizeof(new) - 4, "%s", local);
3068 	cp = new + strlen(new);
3069 	/*
3070 	 * Don't generate dotfile unless requested explicitly.
3071 	 * This covers the case when basename gets truncated off
3072 	 * by buffer size.
3073 	 */
3074 	if (cp > new && cp[-1] != '/')
3075 		*cp++ = '.';
3076 	for (count = 0; count < 100; count++) {
3077 		/* At count 0 try unmodified name */
3078 		if (count)
3079 			sprintf(cp, "%d", count);
3080 		if ((fd = open(count ? new : local,
3081 		    O_RDWR | O_CREAT | O_EXCL, 0666)) >= 0) {
3082 			*name = count ? new : local;
3083 			return (fd);
3084 		}
3085 		if (errno != EEXIST) {
3086 			perror_reply(553, count ? new : local);
3087 			return (-1);
3088 		}
3089 	}
3090 	reply(452, "Unique file name cannot be created.");
3091 	return (-1);
3092 }
3093 
3094 /*
3095  * Format and send reply containing system error number.
3096  */
3097 void
3098 perror_reply(int code, char *string)
3099 {
3100 
3101 	reply(code, "%s: %s.", string, strerror(errno));
3102 }
3103 
3104 static char *onefile[] = {
3105 	"",
3106 	0
3107 };
3108 
3109 void
3110 send_file_list(char *whichf)
3111 {
3112 	struct stat st;
3113 	DIR *dirp = NULL;
3114 	struct dirent *dir;
3115 	FILE *dout = NULL;
3116 	char **dirlist, *dirname;
3117 	int simple = 0;
3118 	int freeglob = 0;
3119 	glob_t gl;
3120 
3121 	if (strpbrk(whichf, "~{[*?") != NULL) {
3122 		int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE;
3123 
3124 		memset(&gl, 0, sizeof(gl));
3125 		gl.gl_matchc = MAXGLOBARGS;
3126 		/*flags |= GLOB_LIMIT;*/
3127 		freeglob = 1;
3128 		if (glob(whichf, flags, 0, &gl)) {
3129 			reply(550, "No matching files found.");
3130 			goto out;
3131 		} else if (gl.gl_pathc == 0) {
3132 			errno = ENOENT;
3133 			perror_reply(550, whichf);
3134 			goto out;
3135 		}
3136 		dirlist = gl.gl_pathv;
3137 	} else {
3138 		onefile[0] = whichf;
3139 		dirlist = onefile;
3140 		simple = 1;
3141 	}
3142 
3143 	while ((dirname = *dirlist++)) {
3144 		if (stat(dirname, &st) < 0) {
3145 			/*
3146 			 * If user typed "ls -l", etc, and the client
3147 			 * used NLST, do what the user meant.
3148 			 */
3149 			if (dirname[0] == '-' && *dirlist == NULL &&
3150 			    dout == NULL)
3151 				retrieve(_PATH_LS " %s", dirname);
3152 			else
3153 				perror_reply(550, whichf);
3154 			goto out;
3155 		}
3156 
3157 		if (S_ISREG(st.st_mode)) {
3158 			if (dout == NULL) {
3159 				dout = dataconn("file list", -1, "w");
3160 				if (dout == NULL)
3161 					goto out;
3162 				STARTXFER;
3163 			}
3164 			START_UNSAFE;
3165 			fprintf(dout, "%s%s\n", dirname,
3166 				type == TYPE_A ? "\r" : "");
3167 			END_UNSAFE;
3168 			if (ferror(dout))
3169 				goto data_err;
3170 			byte_count += strlen(dirname) +
3171 				      (type == TYPE_A ? 2 : 1);
3172 			CHECKOOB(goto abrt);
3173 			continue;
3174 		} else if (!S_ISDIR(st.st_mode))
3175 			continue;
3176 
3177 		if ((dirp = opendir(dirname)) == NULL)
3178 			continue;
3179 
3180 		while ((dir = readdir(dirp)) != NULL) {
3181 			char nbuf[MAXPATHLEN];
3182 
3183 			CHECKOOB(goto abrt);
3184 
3185 			if (strcmp(dir->d_name, ".") == 0)
3186 				continue;
3187 			if (strcmp(dir->d_name, "..") == 0)
3188 				continue;
3189 
3190 			snprintf(nbuf, sizeof(nbuf),
3191 				"%s/%s", dirname, dir->d_name);
3192 
3193 			/*
3194 			 * We have to do a stat to insure it's
3195 			 * not a directory or special file.
3196 			 */
3197 			if (simple || (stat(nbuf, &st) == 0 &&
3198 			    S_ISREG(st.st_mode))) {
3199 				if (dout == NULL) {
3200 					dout = dataconn("file list", -1, "w");
3201 					if (dout == NULL)
3202 						goto out;
3203 					STARTXFER;
3204 				}
3205 				START_UNSAFE;
3206 				if (nbuf[0] == '.' && nbuf[1] == '/')
3207 					fprintf(dout, "%s%s\n", &nbuf[2],
3208 						type == TYPE_A ? "\r" : "");
3209 				else
3210 					fprintf(dout, "%s%s\n", nbuf,
3211 						type == TYPE_A ? "\r" : "");
3212 				END_UNSAFE;
3213 				if (ferror(dout))
3214 					goto data_err;
3215 				byte_count += strlen(nbuf) +
3216 					      (type == TYPE_A ? 2 : 1);
3217 				CHECKOOB(goto abrt);
3218 			}
3219 		}
3220 		closedir(dirp);
3221 		dirp = NULL;
3222 	}
3223 
3224 	if (dout == NULL)
3225 		reply(550, "No files found.");
3226 	else if (ferror(dout))
3227 data_err:	perror_reply(550, "Data connection");
3228 	else
3229 		reply(226, "Transfer complete.");
3230 out:
3231 	if (dout) {
3232 		ENDXFER;
3233 abrt:
3234 		fclose(dout);
3235 		data = -1;
3236 		pdata = -1;
3237 	}
3238 	if (dirp)
3239 		closedir(dirp);
3240 	if (freeglob) {
3241 		freeglob = 0;
3242 		globfree(&gl);
3243 	}
3244 }
3245 
3246 void
3247 reapchild(int signo)
3248 {
3249 	while (waitpid(-1, NULL, WNOHANG) > 0);
3250 }
3251 
3252 static void
3253 appendf(char **strp, char *fmt, ...)
3254 {
3255 	va_list ap;
3256 	char *ostr, *p;
3257 
3258 	va_start(ap, fmt);
3259 	vasprintf(&p, fmt, ap);
3260 	va_end(ap);
3261 	if (p == NULL)
3262 		fatalerror("Ran out of memory.");
3263 	if (*strp == NULL)
3264 		*strp = p;
3265 	else {
3266 		ostr = *strp;
3267 		asprintf(strp, "%s%s", ostr, p);
3268 		if (*strp == NULL)
3269 			fatalerror("Ran out of memory.");
3270 		free(ostr);
3271 	}
3272 }
3273 
3274 static void
3275 logcmd(char *cmd, char *file1, char *file2, off_t cnt)
3276 {
3277 	char *msg = NULL;
3278 	char wd[MAXPATHLEN + 1];
3279 
3280 	if (logging <= 1)
3281 		return;
3282 
3283 	if (getcwd(wd, sizeof(wd) - 1) == NULL)
3284 		strcpy(wd, strerror(errno));
3285 
3286 	appendf(&msg, "%s", cmd);
3287 	if (file1)
3288 		appendf(&msg, " %s", file1);
3289 	if (file2)
3290 		appendf(&msg, " %s", file2);
3291 	if (cnt >= 0)
3292 		appendf(&msg, " = %jd bytes", (intmax_t)cnt);
3293 	appendf(&msg, " (wd: %s", wd);
3294 	if (guest || dochroot)
3295 		appendf(&msg, "; chrooted");
3296 	appendf(&msg, ")");
3297 	syslog(LOG_INFO, "%s", msg);
3298 	free(msg);
3299 }
3300 
3301 static void
3302 logxfer(char *name, off_t size, time_t start)
3303 {
3304 	char buf[MAXPATHLEN + 1024];
3305 	char path[MAXPATHLEN + 1];
3306 	time_t now;
3307 
3308 	if (statfd >= 0) {
3309 		time(&now);
3310 		if (realpath(name, path) == NULL) {
3311 			syslog(LOG_NOTICE, "realpath failed on %s: %m", path);
3312 			return;
3313 		}
3314 		snprintf(buf, sizeof(buf), "%.20s!%s!%s!%s!%jd!%ld\n",
3315 			ctime(&now)+4, ident, remotehost,
3316 			path, (intmax_t)size,
3317 			(long)(now - start + (now == start)));
3318 		write(statfd, buf, strlen(buf));
3319 	}
3320 }
3321 
3322 static char *
3323 doublequote(char *s)
3324 {
3325 	int n;
3326 	char *p, *s2;
3327 
3328 	for (p = s, n = 0; *p; p++)
3329 		if (*p == '"')
3330 			n++;
3331 
3332 	if ((s2 = malloc(p - s + n + 1)) == NULL)
3333 		return (NULL);
3334 
3335 	for (p = s2; *s; s++, p++) {
3336 		if ((*p = *s) == '"')
3337 			*(++p) = '"';
3338 	}
3339 	*p = '\0';
3340 
3341 	return (s2);
3342 }
3343 
3344 /* setup server socket for specified address family */
3345 /* if af is PF_UNSPEC more than one socket may be returned */
3346 /* the returned list is dynamically allocated, so caller needs to free it */
3347 static int *
3348 socksetup(int af, char *bindname, const char *bindport)
3349 {
3350 	struct addrinfo hints, *res, *r;
3351 	int error, maxs, *s, *socks;
3352 	const int on = 1;
3353 
3354 	memset(&hints, 0, sizeof(hints));
3355 	hints.ai_flags = AI_PASSIVE;
3356 	hints.ai_family = af;
3357 	hints.ai_socktype = SOCK_STREAM;
3358 	error = getaddrinfo(bindname, bindport, &hints, &res);
3359 	if (error) {
3360 		syslog(LOG_ERR, "%s", gai_strerror(error));
3361 		if (error == EAI_SYSTEM)
3362 			syslog(LOG_ERR, "%s", strerror(errno));
3363 		return NULL;
3364 	}
3365 
3366 	/* Count max number of sockets we may open */
3367 	for (maxs = 0, r = res; r; r = r->ai_next, maxs++)
3368 		;
3369 	socks = malloc((maxs + 1) * sizeof(int));
3370 	if (!socks) {
3371 		freeaddrinfo(res);
3372 		syslog(LOG_ERR, "couldn't allocate memory for sockets");
3373 		return NULL;
3374 	}
3375 
3376 	*socks = 0;   /* num of sockets counter at start of array */
3377 	s = socks + 1;
3378 	for (r = res; r; r = r->ai_next) {
3379 		*s = socket(r->ai_family, r->ai_socktype, r->ai_protocol);
3380 		if (*s < 0) {
3381 			syslog(LOG_DEBUG, "control socket: %m");
3382 			continue;
3383 		}
3384 		if (setsockopt(*s, SOL_SOCKET, SO_REUSEADDR,
3385 		    &on, sizeof(on)) < 0)
3386 			syslog(LOG_WARNING,
3387 			    "control setsockopt (SO_REUSEADDR): %m");
3388 		if (r->ai_family == AF_INET6) {
3389 			if (setsockopt(*s, IPPROTO_IPV6, IPV6_V6ONLY,
3390 			    &on, sizeof(on)) < 0)
3391 				syslog(LOG_WARNING,
3392 				    "control setsockopt (IPV6_V6ONLY): %m");
3393 		}
3394 		if (bind(*s, r->ai_addr, r->ai_addrlen) < 0) {
3395 			syslog(LOG_DEBUG, "control bind: %m");
3396 			close(*s);
3397 			continue;
3398 		}
3399 		(*socks)++;
3400 		s++;
3401 	}
3402 
3403 	if (res)
3404 		freeaddrinfo(res);
3405 
3406 	if (*socks == 0) {
3407 		syslog(LOG_ERR, "control socket: Couldn't bind to any socket");
3408 		free(socks);
3409 		return NULL;
3410 	}
3411 	return(socks);
3412 }
3413