ftpd.c revision 190828
1/*
2 * Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *	This product includes software developed by the University of
16 *	California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#if 0
35#ifndef lint
36static char copyright[] =
37"@(#) Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994\n\
38	The Regents of the University of California.  All rights reserved.\n";
39#endif /* not lint */
40#endif
41
42#ifndef lint
43#if 0
44static char sccsid[] = "@(#)ftpd.c	8.4 (Berkeley) 4/16/94";
45#endif
46#endif /* not lint */
47
48#include <sys/cdefs.h>
49__FBSDID("$FreeBSD: head/libexec/ftpd/ftpd.c 190828 2009-04-07 20:34:34Z obrien $");
50
51/*
52 * FTP server.
53 */
54#include <sys/param.h>
55#include <sys/ioctl.h>
56#include <sys/mman.h>
57#include <sys/socket.h>
58#include <sys/stat.h>
59#include <sys/time.h>
60#include <sys/wait.h>
61
62#include <netinet/in.h>
63#include <netinet/in_systm.h>
64#include <netinet/ip.h>
65#include <netinet/tcp.h>
66
67#define	FTP_NAMES
68#include <arpa/ftp.h>
69#include <arpa/inet.h>
70#include <arpa/telnet.h>
71
72#include <ctype.h>
73#include <dirent.h>
74#include <err.h>
75#include <errno.h>
76#include <fcntl.h>
77#include <glob.h>
78#include <limits.h>
79#include <netdb.h>
80#include <pwd.h>
81#include <grp.h>
82#include <opie.h>
83#include <signal.h>
84#include <stdint.h>
85#include <stdio.h>
86#include <stdlib.h>
87#include <string.h>
88#include <syslog.h>
89#include <time.h>
90#include <unistd.h>
91#include <libutil.h>
92#ifdef	LOGIN_CAP
93#include <login_cap.h>
94#endif
95
96#ifdef USE_PAM
97#include <security/pam_appl.h>
98#endif
99
100#include "pathnames.h"
101#include "extern.h"
102
103#include <stdarg.h>
104
105static char version[] = "Version 6.00LS";
106#undef main
107
108union sockunion ctrl_addr;
109union sockunion data_source;
110union sockunion data_dest;
111union sockunion his_addr;
112union sockunion pasv_addr;
113
114int	daemon_mode;
115int	data;
116int	dataport;
117int	hostinfo = 1;	/* print host-specific info in messages */
118int	logged_in;
119struct	passwd *pw;
120char	*homedir;
121int	ftpdebug;
122int	timeout = 900;    /* timeout after 15 minutes of inactivity */
123int	maxtimeout = 7200;/* don't allow idle time to be set beyond 2 hours */
124int	logging;
125int	restricted_data_ports = 1;
126int	paranoid = 1;	  /* be extra careful about security */
127int	anon_only = 0;    /* Only anonymous ftp allowed */
128int	assumeutf8 = 0;   /* Assume that server file names are in UTF-8 */
129int	guest;
130int	dochroot;
131char	*chrootdir;
132int	dowtmp = 1;
133int	stats;
134int	statfd = -1;
135int	type;
136int	form;
137int	stru;			/* avoid C keyword */
138int	mode;
139int	usedefault = 1;		/* for data transfers */
140int	pdata = -1;		/* for passive mode */
141int	readonly = 0;		/* Server is in readonly mode.	*/
142int	noepsv = 0;		/* EPSV command is disabled.	*/
143int	noretr = 0;		/* RETR command is disabled.	*/
144int	noguestretr = 0;	/* RETR command is disabled for anon users. */
145int	noguestmkd = 0;		/* MKD command is disabled for anon users. */
146int	noguestmod = 1;		/* anon users may not modify existing files. */
147
148off_t	file_size;
149off_t	byte_count;
150#if !defined(CMASK) || CMASK == 0
151#undef CMASK
152#define CMASK 027
153#endif
154int	defumask = CMASK;		/* default umask value */
155char	tmpline[7];
156char	*hostname;
157int	epsvall = 0;
158
159#ifdef VIRTUAL_HOSTING
160char	*ftpuser;
161
162static struct ftphost {
163	struct ftphost	*next;
164	struct addrinfo *hostinfo;
165	char		*hostname;
166	char		*anonuser;
167	char		*statfile;
168	char		*welcome;
169	char		*loginmsg;
170} *thishost, *firsthost;
171
172#endif
173char	remotehost[NI_MAXHOST];
174char	*ident = NULL;
175
176static char	ttyline[20];
177char		*tty = ttyline;		/* for klogin */
178
179#ifdef USE_PAM
180static int	auth_pam(struct passwd**, const char*);
181pam_handle_t	*pamh = NULL;
182#endif
183
184static struct opie	opiedata;
185static char		opieprompt[OPIE_CHALLENGE_MAX+1];
186static int		pwok;
187
188char	*pid_file = NULL; /* means default location to pidfile(3) */
189
190/*
191 * Limit number of pathnames that glob can return.
192 * A limit of 0 indicates the number of pathnames is unlimited.
193 */
194#define MAXGLOBARGS	16384
195#
196
197/*
198 * Timeout intervals for retrying connections
199 * to hosts that don't accept PORT cmds.  This
200 * is a kludge, but given the problems with TCP...
201 */
202#define	SWAITMAX	90	/* wait at most 90 seconds */
203#define	SWAITINT	5	/* interval between retries */
204
205int	swaitmax = SWAITMAX;
206int	swaitint = SWAITINT;
207
208#ifdef SETPROCTITLE
209#ifdef OLD_SETPROCTITLE
210char	**Argv = NULL;		/* pointer to argument vector */
211char	*LastArgv = NULL;	/* end of argv */
212#endif /* OLD_SETPROCTITLE */
213char	proctitle[LINE_MAX];	/* initial part of title */
214#endif /* SETPROCTITLE */
215
216#define LOGCMD(cmd, file)		logcmd((cmd), (file), NULL, -1)
217#define LOGCMD2(cmd, file1, file2)	logcmd((cmd), (file1), (file2), -1)
218#define LOGBYTES(cmd, file, cnt)	logcmd((cmd), (file), NULL, (cnt))
219
220static	volatile sig_atomic_t recvurg;
221static	int transflag;		/* NB: for debugging only */
222
223#define STARTXFER	flagxfer(1)
224#define ENDXFER		flagxfer(0)
225
226#define START_UNSAFE	maskurg(1)
227#define END_UNSAFE	maskurg(0)
228
229/* It's OK to put an `else' clause after this macro. */
230#define CHECKOOB(action)						\
231	if (recvurg) {							\
232		recvurg = 0;						\
233		if (myoob()) {						\
234			ENDXFER;					\
235			action;						\
236		}							\
237	}
238
239#ifdef VIRTUAL_HOSTING
240static void	 inithosts(int);
241static void	 selecthost(union sockunion *);
242#endif
243static void	 ack(char *);
244static void	 sigurg(int);
245static void	 maskurg(int);
246static void	 flagxfer(int);
247static int	 myoob(void);
248static int	 checkuser(char *, char *, int, char **);
249static FILE	*dataconn(char *, off_t, char *);
250static void	 dolog(struct sockaddr *);
251static void	 end_login(void);
252static FILE	*getdatasock(char *);
253static int	 guniquefd(char *, char **);
254static void	 lostconn(int);
255static void	 sigquit(int);
256static int	 receive_data(FILE *, FILE *);
257static int	 send_data(FILE *, FILE *, size_t, off_t, int);
258static struct passwd *
259		 sgetpwnam(char *);
260static char	*sgetsave(char *);
261static void	 reapchild(int);
262static void	 appendf(char **, char *, ...) __printflike(2, 3);
263static void	 logcmd(char *, char *, char *, off_t);
264static void      logxfer(char *, off_t, time_t);
265static char	*doublequote(char *);
266static int	*socksetup(int, char *, const char *);
267
268int
269main(int argc, char *argv[], char **envp)
270{
271	socklen_t addrlen;
272	int ch, on = 1, tos;
273	char *cp, line[LINE_MAX];
274	FILE *fd;
275	char	*bindname = NULL;
276	const char *bindport = "ftp";
277	int	family = AF_UNSPEC;
278	struct sigaction sa;
279
280	tzset();		/* in case no timezone database in ~ftp */
281	sigemptyset(&sa.sa_mask);
282	sa.sa_flags = SA_RESTART;
283
284#ifdef OLD_SETPROCTITLE
285	/*
286	 *  Save start and extent of argv for setproctitle.
287	 */
288	Argv = argv;
289	while (*envp)
290		envp++;
291	LastArgv = envp[-1] + strlen(envp[-1]);
292#endif /* OLD_SETPROCTITLE */
293
294	/*
295	 * Prevent diagnostic messages from appearing on stderr.
296	 * We run as a daemon or from inetd; in both cases, there's
297	 * more reason in logging to syslog.
298	 */
299	(void) freopen(_PATH_DEVNULL, "w", stderr);
300	opterr = 0;
301
302	/*
303	 * LOG_NDELAY sets up the logging connection immediately,
304	 * necessary for anonymous ftp's that chroot and can't do it later.
305	 */
306	openlog("ftpd", LOG_PID | LOG_NDELAY, LOG_FTP);
307
308	while ((ch = getopt(argc, argv,
309	                    "468a:AdDEhlmMoOp:P:rRSt:T:u:UvW")) != -1) {
310		switch (ch) {
311		case '4':
312			family = (family == AF_INET6) ? AF_UNSPEC : AF_INET;
313			break;
314
315		case '6':
316			family = (family == AF_INET) ? AF_UNSPEC : AF_INET6;
317			break;
318
319		case '8':
320			assumeutf8 = 1;
321			break;
322
323		case 'a':
324			bindname = optarg;
325			break;
326
327		case 'A':
328			anon_only = 1;
329			break;
330
331		case 'd':
332			ftpdebug++;
333			break;
334
335		case 'D':
336			daemon_mode++;
337			break;
338
339		case 'E':
340			noepsv = 1;
341			break;
342
343		case 'h':
344			hostinfo = 0;
345			break;
346
347		case 'l':
348			logging++;	/* > 1 == extra logging */
349			break;
350
351		case 'm':
352			noguestmod = 0;
353			break;
354
355		case 'M':
356			noguestmkd = 1;
357			break;
358
359		case 'o':
360			noretr = 1;
361			break;
362
363		case 'O':
364			noguestretr = 1;
365			break;
366
367		case 'p':
368			pid_file = optarg;
369			break;
370
371		case 'P':
372			bindport = optarg;
373			break;
374
375		case 'r':
376			readonly = 1;
377			break;
378
379		case 'R':
380			paranoid = 0;
381			break;
382
383		case 'S':
384			stats++;
385			break;
386
387		case 't':
388			timeout = atoi(optarg);
389			if (maxtimeout < timeout)
390				maxtimeout = timeout;
391			break;
392
393		case 'T':
394			maxtimeout = atoi(optarg);
395			if (timeout > maxtimeout)
396				timeout = maxtimeout;
397			break;
398
399		case 'u':
400		    {
401			long val = 0;
402
403			val = strtol(optarg, &optarg, 8);
404			if (*optarg != '\0' || val < 0)
405				syslog(LOG_WARNING, "bad value for -u");
406			else
407				defumask = val;
408			break;
409		    }
410		case 'U':
411			restricted_data_ports = 0;
412			break;
413
414		case 'v':
415			ftpdebug++;
416			break;
417
418		case 'W':
419			dowtmp = 0;
420			break;
421
422		default:
423			syslog(LOG_WARNING, "unknown flag -%c ignored", optopt);
424			break;
425		}
426	}
427
428	if (daemon_mode) {
429		int *ctl_sock, fd, maxfd = -1, nfds, i;
430		fd_set defreadfds, readfds;
431		pid_t pid;
432		struct pidfh *pfh;
433
434		if ((pfh = pidfile_open(pid_file, 0600, &pid)) == NULL) {
435			if (errno == EEXIST) {
436				syslog(LOG_ERR, "%s already running, pid %d",
437				       getprogname(), (int)pid);
438				exit(1);
439			}
440			syslog(LOG_WARNING, "pidfile_open: %m");
441		}
442
443		/*
444		 * Detach from parent.
445		 */
446		if (daemon(1, 1) < 0) {
447			syslog(LOG_ERR, "failed to become a daemon");
448			exit(1);
449		}
450
451		if (pfh != NULL && pidfile_write(pfh) == -1)
452			syslog(LOG_WARNING, "pidfile_write: %m");
453
454		sa.sa_handler = reapchild;
455		(void)sigaction(SIGCHLD, &sa, NULL);
456
457#ifdef VIRTUAL_HOSTING
458		inithosts(family);
459#endif
460
461		/*
462		 * Open a socket, bind it to the FTP port, and start
463		 * listening.
464		 */
465		ctl_sock = socksetup(family, bindname, bindport);
466		if (ctl_sock == NULL)
467			exit(1);
468
469		FD_ZERO(&defreadfds);
470		for (i = 1; i <= *ctl_sock; i++) {
471			FD_SET(ctl_sock[i], &defreadfds);
472			if (listen(ctl_sock[i], 32) < 0) {
473				syslog(LOG_ERR, "control listen: %m");
474				exit(1);
475			}
476			if (maxfd < ctl_sock[i])
477				maxfd = ctl_sock[i];
478		}
479
480		/*
481		 * Loop forever accepting connection requests and forking off
482		 * children to handle them.
483		 */
484		while (1) {
485			FD_COPY(&defreadfds, &readfds);
486			nfds = select(maxfd + 1, &readfds, NULL, NULL, 0);
487			if (nfds <= 0) {
488				if (nfds < 0 && errno != EINTR)
489					syslog(LOG_WARNING, "select: %m");
490				continue;
491			}
492
493			pid = -1;
494                        for (i = 1; i <= *ctl_sock; i++)
495				if (FD_ISSET(ctl_sock[i], &readfds)) {
496					addrlen = sizeof(his_addr);
497					fd = accept(ctl_sock[i],
498					    (struct sockaddr *)&his_addr,
499					    &addrlen);
500					if (fd == -1) {
501						syslog(LOG_WARNING,
502						       "accept: %m");
503						continue;
504					}
505					switch (pid = fork()) {
506					case 0:
507						/* child */
508						(void) dup2(fd, 0);
509						(void) dup2(fd, 1);
510						(void) close(fd);
511						for (i = 1; i <= *ctl_sock; i++)
512							close(ctl_sock[i]);
513						if (pfh != NULL)
514							pidfile_close(pfh);
515						goto gotchild;
516					case -1:
517						syslog(LOG_WARNING, "fork: %m");
518						/* FALLTHROUGH */
519					default:
520						close(fd);
521					}
522				}
523		}
524	} else {
525		addrlen = sizeof(his_addr);
526		if (getpeername(0, (struct sockaddr *)&his_addr, &addrlen) < 0) {
527			syslog(LOG_ERR, "getpeername (%s): %m",argv[0]);
528			exit(1);
529		}
530
531#ifdef VIRTUAL_HOSTING
532		if (his_addr.su_family == AF_INET6 &&
533		    IN6_IS_ADDR_V4MAPPED(&his_addr.su_sin6.sin6_addr))
534			family = AF_INET;
535		else
536			family = his_addr.su_family;
537		inithosts(family);
538#endif
539	}
540
541gotchild:
542	sa.sa_handler = SIG_DFL;
543	(void)sigaction(SIGCHLD, &sa, NULL);
544
545	sa.sa_handler = sigurg;
546	sa.sa_flags = 0;		/* don't restart syscalls for SIGURG */
547	(void)sigaction(SIGURG, &sa, NULL);
548
549	sigfillset(&sa.sa_mask);	/* block all signals in handler */
550	sa.sa_flags = SA_RESTART;
551	sa.sa_handler = sigquit;
552	(void)sigaction(SIGHUP, &sa, NULL);
553	(void)sigaction(SIGINT, &sa, NULL);
554	(void)sigaction(SIGQUIT, &sa, NULL);
555	(void)sigaction(SIGTERM, &sa, NULL);
556
557	sa.sa_handler = lostconn;
558	(void)sigaction(SIGPIPE, &sa, NULL);
559
560	addrlen = sizeof(ctrl_addr);
561	if (getsockname(0, (struct sockaddr *)&ctrl_addr, &addrlen) < 0) {
562		syslog(LOG_ERR, "getsockname (%s): %m",argv[0]);
563		exit(1);
564	}
565	dataport = ntohs(ctrl_addr.su_port) - 1; /* as per RFC 959 */
566#ifdef VIRTUAL_HOSTING
567	/* select our identity from virtual host table */
568	selecthost(&ctrl_addr);
569#endif
570#ifdef IP_TOS
571	if (ctrl_addr.su_family == AF_INET)
572      {
573	tos = IPTOS_LOWDELAY;
574	if (setsockopt(0, IPPROTO_IP, IP_TOS, &tos, sizeof(int)) < 0)
575		syslog(LOG_WARNING, "control setsockopt (IP_TOS): %m");
576      }
577#endif
578	/*
579	 * Disable Nagle on the control channel so that we don't have to wait
580	 * for peer's ACK before issuing our next reply.
581	 */
582	if (setsockopt(0, IPPROTO_TCP, TCP_NODELAY, &on, sizeof(on)) < 0)
583		syslog(LOG_WARNING, "control setsockopt (TCP_NODELAY): %m");
584
585	data_source.su_port = htons(ntohs(ctrl_addr.su_port) - 1);
586
587	/* set this here so klogin can use it... */
588	(void)snprintf(ttyline, sizeof(ttyline), "ftp%d", getpid());
589
590	/* Try to handle urgent data inline */
591#ifdef SO_OOBINLINE
592	if (setsockopt(0, SOL_SOCKET, SO_OOBINLINE, &on, sizeof(on)) < 0)
593		syslog(LOG_WARNING, "control setsockopt (SO_OOBINLINE): %m");
594#endif
595
596#ifdef	F_SETOWN
597	if (fcntl(fileno(stdin), F_SETOWN, getpid()) == -1)
598		syslog(LOG_ERR, "fcntl F_SETOWN: %m");
599#endif
600	dolog((struct sockaddr *)&his_addr);
601	/*
602	 * Set up default state
603	 */
604	data = -1;
605	type = TYPE_A;
606	form = FORM_N;
607	stru = STRU_F;
608	mode = MODE_S;
609	tmpline[0] = '\0';
610
611	/* If logins are disabled, print out the message. */
612	if ((fd = fopen(_PATH_NOLOGIN,"r")) != NULL) {
613		while (fgets(line, sizeof(line), fd) != NULL) {
614			if ((cp = strchr(line, '\n')) != NULL)
615				*cp = '\0';
616			lreply(530, "%s", line);
617		}
618		(void) fflush(stdout);
619		(void) fclose(fd);
620		reply(530, "System not available.");
621		exit(0);
622	}
623#ifdef VIRTUAL_HOSTING
624	fd = fopen(thishost->welcome, "r");
625#else
626	fd = fopen(_PATH_FTPWELCOME, "r");
627#endif
628	if (fd != NULL) {
629		while (fgets(line, sizeof(line), fd) != NULL) {
630			if ((cp = strchr(line, '\n')) != NULL)
631				*cp = '\0';
632			lreply(220, "%s", line);
633		}
634		(void) fflush(stdout);
635		(void) fclose(fd);
636		/* reply(220,) must follow */
637	}
638#ifndef VIRTUAL_HOSTING
639	if ((hostname = malloc(MAXHOSTNAMELEN)) == NULL)
640		fatalerror("Ran out of memory.");
641	if (gethostname(hostname, MAXHOSTNAMELEN - 1) < 0)
642		hostname[0] = '\0';
643	hostname[MAXHOSTNAMELEN - 1] = '\0';
644#endif
645	if (hostinfo)
646		reply(220, "%s FTP server (%s) ready.", hostname, version);
647	else
648		reply(220, "FTP server ready.");
649	for (;;)
650		(void) yyparse();
651	/* NOTREACHED */
652}
653
654static void
655lostconn(int signo)
656{
657
658	if (ftpdebug)
659		syslog(LOG_DEBUG, "lost connection");
660	dologout(1);
661}
662
663static void
664sigquit(int signo)
665{
666
667	syslog(LOG_ERR, "got signal %d", signo);
668	dologout(1);
669}
670
671#ifdef VIRTUAL_HOSTING
672/*
673 * read in virtual host tables (if they exist)
674 */
675
676static void
677inithosts(int family)
678{
679	int insert;
680	size_t len;
681	FILE *fp;
682	char *cp, *mp, *line;
683	char *hostname;
684	char *vhost, *anonuser, *statfile, *welcome, *loginmsg;
685	struct ftphost *hrp, *lhrp;
686	struct addrinfo hints, *res, *ai;
687
688	/*
689	 * Fill in the default host information
690	 */
691	if ((hostname = malloc(MAXHOSTNAMELEN)) == NULL)
692		fatalerror("Ran out of memory.");
693	if (gethostname(hostname, MAXHOSTNAMELEN - 1) < 0)
694		hostname[0] = '\0';
695	hostname[MAXHOSTNAMELEN - 1] = '\0';
696	if ((hrp = malloc(sizeof(struct ftphost))) == NULL)
697		fatalerror("Ran out of memory.");
698	hrp->hostname = hostname;
699	hrp->hostinfo = NULL;
700
701	memset(&hints, 0, sizeof(hints));
702	hints.ai_flags = AI_PASSIVE;
703	hints.ai_family = family;
704	hints.ai_socktype = SOCK_STREAM;
705	if (getaddrinfo(hrp->hostname, NULL, &hints, &res) == 0)
706		hrp->hostinfo = res;
707	hrp->statfile = _PATH_FTPDSTATFILE;
708	hrp->welcome  = _PATH_FTPWELCOME;
709	hrp->loginmsg = _PATH_FTPLOGINMESG;
710	hrp->anonuser = "ftp";
711	hrp->next = NULL;
712	thishost = firsthost = lhrp = hrp;
713	if ((fp = fopen(_PATH_FTPHOSTS, "r")) != NULL) {
714		int addrsize, gothost;
715		void *addr;
716		struct hostent *hp;
717
718		while ((line = fgetln(fp, &len)) != NULL) {
719			int	i, hp_error;
720
721			/* skip comments */
722			if (line[0] == '#')
723				continue;
724			if (line[len - 1] == '\n') {
725				line[len - 1] = '\0';
726				mp = NULL;
727			} else {
728				if ((mp = malloc(len + 1)) == NULL)
729					fatalerror("Ran out of memory.");
730				memcpy(mp, line, len);
731				mp[len] = '\0';
732				line = mp;
733			}
734			cp = strtok(line, " \t");
735			/* skip empty lines */
736			if (cp == NULL)
737				goto nextline;
738			vhost = cp;
739
740			/* set defaults */
741			anonuser = "ftp";
742			statfile = _PATH_FTPDSTATFILE;
743			welcome  = _PATH_FTPWELCOME;
744			loginmsg = _PATH_FTPLOGINMESG;
745
746			/*
747			 * Preparse the line so we can use its info
748			 * for all the addresses associated with
749			 * the virtual host name.
750			 * Field 0, the virtual host name, is special:
751			 * it's already parsed off and will be strdup'ed
752			 * later, after we know its canonical form.
753			 */
754			for (i = 1; i < 5 && (cp = strtok(NULL, " \t")); i++)
755				if (*cp != '-' && (cp = strdup(cp)))
756					switch (i) {
757					case 1:	/* anon user permissions */
758						anonuser = cp;
759						break;
760					case 2: /* statistics file */
761						statfile = cp;
762						break;
763					case 3: /* welcome message */
764						welcome  = cp;
765						break;
766					case 4: /* login message */
767						loginmsg = cp;
768						break;
769					default: /* programming error */
770						abort();
771						/* NOTREACHED */
772					}
773
774			hints.ai_flags = AI_PASSIVE;
775			hints.ai_family = family;
776			hints.ai_socktype = SOCK_STREAM;
777			if (getaddrinfo(vhost, NULL, &hints, &res) != 0)
778				goto nextline;
779			for (ai = res; ai != NULL && ai->ai_addr != NULL;
780			     ai = ai->ai_next) {
781
782			gothost = 0;
783			for (hrp = firsthost; hrp != NULL; hrp = hrp->next) {
784				struct addrinfo *hi;
785
786				for (hi = hrp->hostinfo; hi != NULL;
787				     hi = hi->ai_next)
788					if (hi->ai_addrlen == ai->ai_addrlen &&
789					    memcmp(hi->ai_addr,
790						   ai->ai_addr,
791						   ai->ai_addr->sa_len) == 0) {
792						gothost++;
793						break;
794					}
795				if (gothost)
796					break;
797			}
798			if (hrp == NULL) {
799				if ((hrp = malloc(sizeof(struct ftphost))) == NULL)
800					goto nextline;
801				hrp->hostname = NULL;
802				insert = 1;
803			} else {
804				if (hrp->hostinfo && hrp->hostinfo != res)
805					freeaddrinfo(hrp->hostinfo);
806				insert = 0; /* host already in the chain */
807			}
808			hrp->hostinfo = res;
809
810			/*
811			 * determine hostname to use.
812			 * force defined name if there is a valid alias
813			 * otherwise fallback to primary hostname
814			 */
815			/* XXX: getaddrinfo() can't do alias check */
816			switch(hrp->hostinfo->ai_family) {
817			case AF_INET:
818				addr = &((struct sockaddr_in *)hrp->hostinfo->ai_addr)->sin_addr;
819				addrsize = sizeof(struct in_addr);
820				break;
821			case AF_INET6:
822				addr = &((struct sockaddr_in6 *)hrp->hostinfo->ai_addr)->sin6_addr;
823				addrsize = sizeof(struct in6_addr);
824				break;
825			default:
826				/* should not reach here */
827				freeaddrinfo(hrp->hostinfo);
828				if (insert)
829					free(hrp); /*not in chain, can free*/
830				else
831					hrp->hostinfo = NULL; /*mark as blank*/
832				goto nextline;
833				/* NOTREACHED */
834			}
835			if ((hp = getipnodebyaddr(addr, addrsize,
836						  hrp->hostinfo->ai_family,
837						  &hp_error)) != NULL) {
838				if (strcmp(vhost, hp->h_name) != 0) {
839					if (hp->h_aliases == NULL)
840						vhost = hp->h_name;
841					else {
842						i = 0;
843						while (hp->h_aliases[i] &&
844						       strcmp(vhost, hp->h_aliases[i]) != 0)
845							++i;
846						if (hp->h_aliases[i] == NULL)
847							vhost = hp->h_name;
848					}
849				}
850			}
851			if (hrp->hostname &&
852			    strcmp(hrp->hostname, vhost) != 0) {
853				free(hrp->hostname);
854				hrp->hostname = NULL;
855			}
856			if (hrp->hostname == NULL &&
857			    (hrp->hostname = strdup(vhost)) == NULL) {
858				freeaddrinfo(hrp->hostinfo);
859				hrp->hostinfo = NULL; /* mark as blank */
860				if (hp)
861					freehostent(hp);
862				goto nextline;
863			}
864			hrp->anonuser = anonuser;
865			hrp->statfile = statfile;
866			hrp->welcome  = welcome;
867			hrp->loginmsg = loginmsg;
868			if (insert) {
869				hrp->next  = NULL;
870				lhrp->next = hrp;
871				lhrp = hrp;
872			}
873			if (hp)
874				freehostent(hp);
875		      }
876nextline:
877			if (mp)
878				free(mp);
879		}
880		(void) fclose(fp);
881	}
882}
883
884static void
885selecthost(union sockunion *su)
886{
887	struct ftphost	*hrp;
888	u_int16_t port;
889#ifdef INET6
890	struct in6_addr *mapped_in6 = NULL;
891#endif
892	struct addrinfo *hi;
893
894#ifdef INET6
895	/*
896	 * XXX IPv4 mapped IPv6 addr consideraton,
897	 * specified in rfc2373.
898	 */
899	if (su->su_family == AF_INET6 &&
900	    IN6_IS_ADDR_V4MAPPED(&su->su_sin6.sin6_addr))
901		mapped_in6 = &su->su_sin6.sin6_addr;
902#endif
903
904	hrp = thishost = firsthost;	/* default */
905	port = su->su_port;
906	su->su_port = 0;
907	while (hrp != NULL) {
908	    for (hi = hrp->hostinfo; hi != NULL; hi = hi->ai_next) {
909		if (memcmp(su, hi->ai_addr, hi->ai_addrlen) == 0) {
910			thishost = hrp;
911			goto found;
912		}
913#ifdef INET6
914		/* XXX IPv4 mapped IPv6 addr consideraton */
915		if (hi->ai_addr->sa_family == AF_INET && mapped_in6 != NULL &&
916		    (memcmp(&mapped_in6->s6_addr[12],
917			    &((struct sockaddr_in *)hi->ai_addr)->sin_addr,
918			    sizeof(struct in_addr)) == 0)) {
919			thishost = hrp;
920			goto found;
921		}
922#endif
923	    }
924	    hrp = hrp->next;
925	}
926found:
927	su->su_port = port;
928	/* setup static variables as appropriate */
929	hostname = thishost->hostname;
930	ftpuser = thishost->anonuser;
931}
932#endif
933
934/*
935 * Helper function for sgetpwnam().
936 */
937static char *
938sgetsave(char *s)
939{
940	char *new = malloc(strlen(s) + 1);
941
942	if (new == NULL) {
943		reply(421, "Ran out of memory.");
944		dologout(1);
945		/* NOTREACHED */
946	}
947	(void) strcpy(new, s);
948	return (new);
949}
950
951/*
952 * Save the result of a getpwnam.  Used for USER command, since
953 * the data returned must not be clobbered by any other command
954 * (e.g., globbing).
955 * NB: The data returned by sgetpwnam() will remain valid until
956 * the next call to this function.  Its difference from getpwnam()
957 * is that sgetpwnam() is known to be called from ftpd code only.
958 */
959static struct passwd *
960sgetpwnam(char *name)
961{
962	static struct passwd save;
963	struct passwd *p;
964
965	if ((p = getpwnam(name)) == NULL)
966		return (p);
967	if (save.pw_name) {
968		free(save.pw_name);
969		free(save.pw_passwd);
970		free(save.pw_gecos);
971		free(save.pw_dir);
972		free(save.pw_shell);
973	}
974	save = *p;
975	save.pw_name = sgetsave(p->pw_name);
976	save.pw_passwd = sgetsave(p->pw_passwd);
977	save.pw_gecos = sgetsave(p->pw_gecos);
978	save.pw_dir = sgetsave(p->pw_dir);
979	save.pw_shell = sgetsave(p->pw_shell);
980	return (&save);
981}
982
983static int login_attempts;	/* number of failed login attempts */
984static int askpasswd;		/* had user command, ask for passwd */
985static char curname[MAXLOGNAME];	/* current USER name */
986
987/*
988 * USER command.
989 * Sets global passwd pointer pw if named account exists and is acceptable;
990 * sets askpasswd if a PASS command is expected.  If logged in previously,
991 * need to reset state.  If name is "ftp" or "anonymous", the name is not in
992 * _PATH_FTPUSERS, and ftp account exists, set guest and pw, then just return.
993 * If account doesn't exist, ask for passwd anyway.  Otherwise, check user
994 * requesting login privileges.  Disallow anyone who does not have a standard
995 * shell as returned by getusershell().  Disallow anyone mentioned in the file
996 * _PATH_FTPUSERS to allow people such as root and uucp to be avoided.
997 */
998void
999user(char *name)
1000{
1001	char *cp, *shell;
1002
1003	if (logged_in) {
1004		if (guest) {
1005			reply(530, "Can't change user from guest login.");
1006			return;
1007		} else if (dochroot) {
1008			reply(530, "Can't change user from chroot user.");
1009			return;
1010		}
1011		end_login();
1012	}
1013
1014	guest = 0;
1015#ifdef VIRTUAL_HOSTING
1016	pw = sgetpwnam(thishost->anonuser);
1017#else
1018	pw = sgetpwnam("ftp");
1019#endif
1020	if (strcmp(name, "ftp") == 0 || strcmp(name, "anonymous") == 0) {
1021		if (checkuser(_PATH_FTPUSERS, "ftp", 0, NULL) ||
1022		    checkuser(_PATH_FTPUSERS, "anonymous", 0, NULL))
1023			reply(530, "User %s access denied.", name);
1024		else if (pw != NULL) {
1025			guest = 1;
1026			askpasswd = 1;
1027			reply(331,
1028			"Guest login ok, send your email address as password.");
1029		} else
1030			reply(530, "User %s unknown.", name);
1031		if (!askpasswd && logging)
1032			syslog(LOG_NOTICE,
1033			    "ANONYMOUS FTP LOGIN REFUSED FROM %s", remotehost);
1034		return;
1035	}
1036	if (anon_only != 0) {
1037		reply(530, "Sorry, only anonymous ftp allowed.");
1038		return;
1039	}
1040
1041	if ((pw = sgetpwnam(name))) {
1042		if ((shell = pw->pw_shell) == NULL || *shell == 0)
1043			shell = _PATH_BSHELL;
1044		setusershell();
1045		while ((cp = getusershell()) != NULL)
1046			if (strcmp(cp, shell) == 0)
1047				break;
1048		endusershell();
1049
1050		if (cp == NULL || checkuser(_PATH_FTPUSERS, name, 1, NULL)) {
1051			reply(530, "User %s access denied.", name);
1052			if (logging)
1053				syslog(LOG_NOTICE,
1054				    "FTP LOGIN REFUSED FROM %s, %s",
1055				    remotehost, name);
1056			pw = NULL;
1057			return;
1058		}
1059	}
1060	if (logging)
1061		strncpy(curname, name, sizeof(curname)-1);
1062
1063	pwok = 0;
1064#ifdef USE_PAM
1065	/* XXX Kluge! The conversation mechanism needs to be fixed. */
1066#endif
1067	if (opiechallenge(&opiedata, name, opieprompt) == 0) {
1068		pwok = (pw != NULL) &&
1069		       opieaccessfile(remotehost) &&
1070		       opiealways(pw->pw_dir);
1071		reply(331, "Response to %s %s for %s.",
1072		      opieprompt, pwok ? "requested" : "required", name);
1073	} else {
1074		pwok = 1;
1075		reply(331, "Password required for %s.", name);
1076	}
1077	askpasswd = 1;
1078	/*
1079	 * Delay before reading passwd after first failed
1080	 * attempt to slow down passwd-guessing programs.
1081	 */
1082	if (login_attempts)
1083		sleep(login_attempts);
1084}
1085
1086/*
1087 * Check if a user is in the file "fname",
1088 * return a pointer to a malloc'd string with the rest
1089 * of the matching line in "residue" if not NULL.
1090 */
1091static int
1092checkuser(char *fname, char *name, int pwset, char **residue)
1093{
1094	FILE *fd;
1095	int found = 0;
1096	size_t len;
1097	char *line, *mp, *p;
1098
1099	if ((fd = fopen(fname, "r")) != NULL) {
1100		while (!found && (line = fgetln(fd, &len)) != NULL) {
1101			/* skip comments */
1102			if (line[0] == '#')
1103				continue;
1104			if (line[len - 1] == '\n') {
1105				line[len - 1] = '\0';
1106				mp = NULL;
1107			} else {
1108				if ((mp = malloc(len + 1)) == NULL)
1109					fatalerror("Ran out of memory.");
1110				memcpy(mp, line, len);
1111				mp[len] = '\0';
1112				line = mp;
1113			}
1114			/* avoid possible leading and trailing whitespace */
1115			p = strtok(line, " \t");
1116			/* skip empty lines */
1117			if (p == NULL)
1118				goto nextline;
1119			/*
1120			 * if first chr is '@', check group membership
1121			 */
1122			if (p[0] == '@') {
1123				int i = 0;
1124				struct group *grp;
1125
1126				if (p[1] == '\0') /* single @ matches anyone */
1127					found = 1;
1128				else {
1129					if ((grp = getgrnam(p+1)) == NULL)
1130						goto nextline;
1131					/*
1132					 * Check user's default group
1133					 */
1134					if (pwset && grp->gr_gid == pw->pw_gid)
1135						found = 1;
1136					/*
1137					 * Check supplementary groups
1138					 */
1139					while (!found && grp->gr_mem[i])
1140						found = strcmp(name,
1141							grp->gr_mem[i++])
1142							== 0;
1143				}
1144			}
1145			/*
1146			 * Otherwise, just check for username match
1147			 */
1148			else
1149				found = strcmp(p, name) == 0;
1150			/*
1151			 * Save the rest of line to "residue" if matched
1152			 */
1153			if (found && residue) {
1154				if ((p = strtok(NULL, "")) != NULL)
1155					p += strspn(p, " \t");
1156				if (p && *p) {
1157				 	if ((*residue = strdup(p)) == NULL)
1158						fatalerror("Ran out of memory.");
1159				} else
1160					*residue = NULL;
1161			}
1162nextline:
1163			if (mp)
1164				free(mp);
1165		}
1166		(void) fclose(fd);
1167	}
1168	return (found);
1169}
1170
1171/*
1172 * Terminate login as previous user, if any, resetting state;
1173 * used when USER command is given or login fails.
1174 */
1175static void
1176end_login(void)
1177{
1178#ifdef USE_PAM
1179	int e;
1180#endif
1181
1182	(void) seteuid(0);
1183	if (logged_in && dowtmp)
1184		ftpd_logwtmp(ttyline, "", NULL);
1185	pw = NULL;
1186#ifdef	LOGIN_CAP
1187	setusercontext(NULL, getpwuid(0), 0,
1188		       LOGIN_SETPRIORITY|LOGIN_SETRESOURCES|LOGIN_SETUMASK|
1189		       LOGIN_SETMAC);
1190#endif
1191#ifdef USE_PAM
1192	if (pamh) {
1193		if ((e = pam_setcred(pamh, PAM_DELETE_CRED)) != PAM_SUCCESS)
1194			syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, e));
1195		if ((e = pam_close_session(pamh,0)) != PAM_SUCCESS)
1196			syslog(LOG_ERR, "pam_close_session: %s", pam_strerror(pamh, e));
1197		if ((e = pam_end(pamh, e)) != PAM_SUCCESS)
1198			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1199		pamh = NULL;
1200	}
1201#endif
1202	logged_in = 0;
1203	guest = 0;
1204	dochroot = 0;
1205}
1206
1207#ifdef USE_PAM
1208
1209/*
1210 * the following code is stolen from imap-uw PAM authentication module and
1211 * login.c
1212 */
1213#define COPY_STRING(s) (s ? strdup(s) : NULL)
1214
1215struct cred_t {
1216	const char *uname;		/* user name */
1217	const char *pass;		/* password */
1218};
1219typedef struct cred_t cred_t;
1220
1221static int
1222auth_conv(int num_msg, const struct pam_message **msg,
1223	  struct pam_response **resp, void *appdata)
1224{
1225	int i;
1226	cred_t *cred = (cred_t *) appdata;
1227	struct pam_response *reply;
1228
1229	reply = calloc(num_msg, sizeof *reply);
1230	if (reply == NULL)
1231		return PAM_BUF_ERR;
1232
1233	for (i = 0; i < num_msg; i++) {
1234		switch (msg[i]->msg_style) {
1235		case PAM_PROMPT_ECHO_ON:	/* assume want user name */
1236			reply[i].resp_retcode = PAM_SUCCESS;
1237			reply[i].resp = COPY_STRING(cred->uname);
1238			/* PAM frees resp. */
1239			break;
1240		case PAM_PROMPT_ECHO_OFF:	/* assume want password */
1241			reply[i].resp_retcode = PAM_SUCCESS;
1242			reply[i].resp = COPY_STRING(cred->pass);
1243			/* PAM frees resp. */
1244			break;
1245		case PAM_TEXT_INFO:
1246		case PAM_ERROR_MSG:
1247			reply[i].resp_retcode = PAM_SUCCESS;
1248			reply[i].resp = NULL;
1249			break;
1250		default:			/* unknown message style */
1251			free(reply);
1252			return PAM_CONV_ERR;
1253		}
1254	}
1255
1256	*resp = reply;
1257	return PAM_SUCCESS;
1258}
1259
1260/*
1261 * Attempt to authenticate the user using PAM.  Returns 0 if the user is
1262 * authenticated, or 1 if not authenticated.  If some sort of PAM system
1263 * error occurs (e.g., the "/etc/pam.conf" file is missing) then this
1264 * function returns -1.  This can be used as an indication that we should
1265 * fall back to a different authentication mechanism.
1266 */
1267static int
1268auth_pam(struct passwd **ppw, const char *pass)
1269{
1270	const char *tmpl_user;
1271	const void *item;
1272	int rval;
1273	int e;
1274	cred_t auth_cred = { (*ppw)->pw_name, pass };
1275	struct pam_conv conv = { &auth_conv, &auth_cred };
1276
1277	e = pam_start("ftpd", (*ppw)->pw_name, &conv, &pamh);
1278	if (e != PAM_SUCCESS) {
1279		/*
1280		 * In OpenPAM, it's OK to pass NULL to pam_strerror()
1281		 * if context creation has failed in the first place.
1282		 */
1283		syslog(LOG_ERR, "pam_start: %s", pam_strerror(NULL, e));
1284		return -1;
1285	}
1286
1287	e = pam_set_item(pamh, PAM_RHOST, remotehost);
1288	if (e != PAM_SUCCESS) {
1289		syslog(LOG_ERR, "pam_set_item(PAM_RHOST): %s",
1290			pam_strerror(pamh, e));
1291		if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
1292			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1293		}
1294		pamh = NULL;
1295		return -1;
1296	}
1297
1298	e = pam_authenticate(pamh, 0);
1299	switch (e) {
1300	case PAM_SUCCESS:
1301		/*
1302		 * With PAM we support the concept of a "template"
1303		 * user.  The user enters a login name which is
1304		 * authenticated by PAM, usually via a remote service
1305		 * such as RADIUS or TACACS+.  If authentication
1306		 * succeeds, a different but related "template" name
1307		 * is used for setting the credentials, shell, and
1308		 * home directory.  The name the user enters need only
1309		 * exist on the remote authentication server, but the
1310		 * template name must be present in the local password
1311		 * database.
1312		 *
1313		 * This is supported by two various mechanisms in the
1314		 * individual modules.  However, from the application's
1315		 * point of view, the template user is always passed
1316		 * back as a changed value of the PAM_USER item.
1317		 */
1318		if ((e = pam_get_item(pamh, PAM_USER, &item)) ==
1319		    PAM_SUCCESS) {
1320			tmpl_user = (const char *) item;
1321			if (strcmp((*ppw)->pw_name, tmpl_user) != 0)
1322				*ppw = getpwnam(tmpl_user);
1323		} else
1324			syslog(LOG_ERR, "Couldn't get PAM_USER: %s",
1325			    pam_strerror(pamh, e));
1326		rval = 0;
1327		break;
1328
1329	case PAM_AUTH_ERR:
1330	case PAM_USER_UNKNOWN:
1331	case PAM_MAXTRIES:
1332		rval = 1;
1333		break;
1334
1335	default:
1336		syslog(LOG_ERR, "pam_authenticate: %s", pam_strerror(pamh, e));
1337		rval = -1;
1338		break;
1339	}
1340
1341	if (rval == 0) {
1342		e = pam_acct_mgmt(pamh, 0);
1343		if (e != PAM_SUCCESS) {
1344			syslog(LOG_ERR, "pam_acct_mgmt: %s",
1345						pam_strerror(pamh, e));
1346			rval = 1;
1347		}
1348	}
1349
1350	if (rval != 0) {
1351		if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
1352			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1353		}
1354		pamh = NULL;
1355	}
1356	return rval;
1357}
1358
1359#endif /* USE_PAM */
1360
1361void
1362pass(char *passwd)
1363{
1364	int rval;
1365	FILE *fd;
1366#ifdef	LOGIN_CAP
1367	login_cap_t *lc = NULL;
1368#endif
1369#ifdef USE_PAM
1370	int e;
1371#endif
1372	char *residue = NULL;
1373	char *xpasswd;
1374
1375	if (logged_in || askpasswd == 0) {
1376		reply(503, "Login with USER first.");
1377		return;
1378	}
1379	askpasswd = 0;
1380	if (!guest) {		/* "ftp" is only account allowed no password */
1381		if (pw == NULL) {
1382			rval = 1;	/* failure below */
1383			goto skip;
1384		}
1385#ifdef USE_PAM
1386		rval = auth_pam(&pw, passwd);
1387		if (rval >= 0) {
1388			opieunlock();
1389			goto skip;
1390		}
1391#endif
1392		if (opieverify(&opiedata, passwd) == 0)
1393			xpasswd = pw->pw_passwd;
1394		else if (pwok) {
1395			xpasswd = crypt(passwd, pw->pw_passwd);
1396			if (passwd[0] == '\0' && pw->pw_passwd[0] != '\0')
1397				xpasswd = ":";
1398		} else {
1399			rval = 1;
1400			goto skip;
1401		}
1402		rval = strcmp(pw->pw_passwd, xpasswd);
1403		if (pw->pw_expire && time(NULL) >= pw->pw_expire)
1404			rval = 1;	/* failure */
1405skip:
1406		/*
1407		 * If rval == 1, the user failed the authentication check
1408		 * above.  If rval == 0, either PAM or local authentication
1409		 * succeeded.
1410		 */
1411		if (rval) {
1412			reply(530, "Login incorrect.");
1413			if (logging) {
1414				syslog(LOG_NOTICE,
1415				    "FTP LOGIN FAILED FROM %s",
1416				    remotehost);
1417				syslog(LOG_AUTHPRIV | LOG_NOTICE,
1418				    "FTP LOGIN FAILED FROM %s, %s",
1419				    remotehost, curname);
1420			}
1421			pw = NULL;
1422			if (login_attempts++ >= 5) {
1423				syslog(LOG_NOTICE,
1424				    "repeated login failures from %s",
1425				    remotehost);
1426				exit(0);
1427			}
1428			return;
1429		}
1430	}
1431	login_attempts = 0;		/* this time successful */
1432	if (setegid(pw->pw_gid) < 0) {
1433		reply(550, "Can't set gid.");
1434		return;
1435	}
1436	/* May be overridden by login.conf */
1437	(void) umask(defumask);
1438#ifdef	LOGIN_CAP
1439	if ((lc = login_getpwclass(pw)) != NULL) {
1440		char	remote_ip[NI_MAXHOST];
1441
1442		if (getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
1443			remote_ip, sizeof(remote_ip) - 1, NULL, 0,
1444			NI_NUMERICHOST))
1445				*remote_ip = 0;
1446		remote_ip[sizeof(remote_ip) - 1] = 0;
1447		if (!auth_hostok(lc, remotehost, remote_ip)) {
1448			syslog(LOG_INFO|LOG_AUTH,
1449			    "FTP LOGIN FAILED (HOST) as %s: permission denied.",
1450			    pw->pw_name);
1451			reply(530, "Permission denied.");
1452			pw = NULL;
1453			return;
1454		}
1455		if (!auth_timeok(lc, time(NULL))) {
1456			reply(530, "Login not available right now.");
1457			pw = NULL;
1458			return;
1459		}
1460	}
1461	setusercontext(lc, pw, 0,
1462		LOGIN_SETLOGIN|LOGIN_SETGROUP|LOGIN_SETPRIORITY|
1463		LOGIN_SETRESOURCES|LOGIN_SETUMASK|LOGIN_SETMAC);
1464#else
1465	setlogin(pw->pw_name);
1466	(void) initgroups(pw->pw_name, pw->pw_gid);
1467#endif
1468
1469#ifdef USE_PAM
1470	if (pamh) {
1471		if ((e = pam_open_session(pamh, 0)) != PAM_SUCCESS) {
1472			syslog(LOG_ERR, "pam_open_session: %s", pam_strerror(pamh, e));
1473		} else if ((e = pam_setcred(pamh, PAM_ESTABLISH_CRED)) != PAM_SUCCESS) {
1474			syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, e));
1475		}
1476	}
1477#endif
1478
1479	/* open wtmp before chroot */
1480	if (dowtmp)
1481		ftpd_logwtmp(ttyline, pw->pw_name,
1482		    (struct sockaddr *)&his_addr);
1483	logged_in = 1;
1484
1485	if (guest && stats && statfd < 0)
1486#ifdef VIRTUAL_HOSTING
1487		statfd = open(thishost->statfile, O_WRONLY|O_APPEND);
1488#else
1489		statfd = open(_PATH_FTPDSTATFILE, O_WRONLY|O_APPEND);
1490#endif
1491		if (statfd < 0)
1492			stats = 0;
1493
1494	dochroot =
1495		checkuser(_PATH_FTPCHROOT, pw->pw_name, 1, &residue)
1496#ifdef	LOGIN_CAP	/* Allow login.conf configuration as well */
1497		|| login_getcapbool(lc, "ftp-chroot", 0)
1498#endif
1499	;
1500	chrootdir = NULL;
1501	/*
1502	 * For a chrooted local user,
1503	 * a) see whether ftpchroot(5) specifies a chroot directory,
1504	 * b) extract the directory pathname from the line,
1505	 * c) expand it to the absolute pathname if necessary.
1506	 */
1507	if (dochroot && residue &&
1508	    (chrootdir = strtok(residue, " \t")) != NULL) {
1509		if (chrootdir[0] != '/')
1510			asprintf(&chrootdir, "%s/%s", pw->pw_dir, chrootdir);
1511		else
1512			chrootdir = strdup(chrootdir); /* make it permanent */
1513		if (chrootdir == NULL)
1514			fatalerror("Ran out of memory.");
1515	}
1516	if (guest || dochroot) {
1517		/*
1518		 * If no chroot directory set yet, use the login directory.
1519		 * Copy it so it can be modified while pw->pw_dir stays intact.
1520		 */
1521		if (chrootdir == NULL &&
1522		    (chrootdir = strdup(pw->pw_dir)) == NULL)
1523			fatalerror("Ran out of memory.");
1524		/*
1525		 * Check for the "/chroot/./home" syntax,
1526		 * separate the chroot and home directory pathnames.
1527		 */
1528		if ((homedir = strstr(chrootdir, "/./")) != NULL) {
1529			*(homedir++) = '\0';	/* wipe '/' */
1530			homedir++;		/* skip '.' */
1531		} else {
1532			/*
1533			 * We MUST do a chdir() after the chroot. Otherwise
1534			 * the old current directory will be accessible as "."
1535			 * outside the new root!
1536			 */
1537			homedir = "/";
1538		}
1539		/*
1540		 * Finally, do chroot()
1541		 */
1542		if (chroot(chrootdir) < 0) {
1543			reply(550, "Can't change root.");
1544			goto bad;
1545		}
1546	} else	/* real user w/o chroot */
1547		homedir = pw->pw_dir;
1548	/*
1549	 * Set euid *before* doing chdir() so
1550	 * a) the user won't be carried to a directory that he couldn't reach
1551	 *    on his own due to no permission to upper path components,
1552	 * b) NFS mounted homedirs w/restrictive permissions will be accessible
1553	 *    (uid 0 has no root power over NFS if not mapped explicitly.)
1554	 */
1555	if (seteuid(pw->pw_uid) < 0) {
1556		reply(550, "Can't set uid.");
1557		goto bad;
1558	}
1559	if (chdir(homedir) < 0) {
1560		if (guest || dochroot) {
1561			reply(550, "Can't change to base directory.");
1562			goto bad;
1563		} else {
1564			if (chdir("/") < 0) {
1565				reply(550, "Root is inaccessible.");
1566				goto bad;
1567			}
1568			lreply(230, "No directory! Logging in with home=/.");
1569		}
1570	}
1571
1572	/*
1573	 * Display a login message, if it exists.
1574	 * N.B. reply(230,) must follow the message.
1575	 */
1576#ifdef VIRTUAL_HOSTING
1577	fd = fopen(thishost->loginmsg, "r");
1578#else
1579	fd = fopen(_PATH_FTPLOGINMESG, "r");
1580#endif
1581	if (fd != NULL) {
1582		char *cp, line[LINE_MAX];
1583
1584		while (fgets(line, sizeof(line), fd) != NULL) {
1585			if ((cp = strchr(line, '\n')) != NULL)
1586				*cp = '\0';
1587			lreply(230, "%s", line);
1588		}
1589		(void) fflush(stdout);
1590		(void) fclose(fd);
1591	}
1592	if (guest) {
1593		if (ident != NULL)
1594			free(ident);
1595		ident = strdup(passwd);
1596		if (ident == NULL)
1597			fatalerror("Ran out of memory.");
1598
1599		reply(230, "Guest login ok, access restrictions apply.");
1600#ifdef SETPROCTITLE
1601#ifdef VIRTUAL_HOSTING
1602		if (thishost != firsthost)
1603			snprintf(proctitle, sizeof(proctitle),
1604				 "%s: anonymous(%s)/%s", remotehost, hostname,
1605				 passwd);
1606		else
1607#endif
1608			snprintf(proctitle, sizeof(proctitle),
1609				 "%s: anonymous/%s", remotehost, passwd);
1610		setproctitle("%s", proctitle);
1611#endif /* SETPROCTITLE */
1612		if (logging)
1613			syslog(LOG_INFO, "ANONYMOUS FTP LOGIN FROM %s, %s",
1614			    remotehost, passwd);
1615	} else {
1616		if (dochroot)
1617			reply(230, "User %s logged in, "
1618				   "access restrictions apply.", pw->pw_name);
1619		else
1620			reply(230, "User %s logged in.", pw->pw_name);
1621
1622#ifdef SETPROCTITLE
1623		snprintf(proctitle, sizeof(proctitle),
1624			 "%s: user/%s", remotehost, pw->pw_name);
1625		setproctitle("%s", proctitle);
1626#endif /* SETPROCTITLE */
1627		if (logging)
1628			syslog(LOG_INFO, "FTP LOGIN FROM %s as %s",
1629			    remotehost, pw->pw_name);
1630	}
1631	if (logging && (guest || dochroot))
1632		syslog(LOG_INFO, "session root changed to %s", chrootdir);
1633#ifdef	LOGIN_CAP
1634	login_close(lc);
1635#endif
1636	if (residue)
1637		free(residue);
1638	return;
1639bad:
1640	/* Forget all about it... */
1641#ifdef	LOGIN_CAP
1642	login_close(lc);
1643#endif
1644	if (residue)
1645		free(residue);
1646	end_login();
1647}
1648
1649void
1650retrieve(char *cmd, char *name)
1651{
1652	FILE *fin, *dout;
1653	struct stat st;
1654	int (*closefunc)(FILE *);
1655	time_t start;
1656
1657	if (cmd == 0) {
1658		fin = fopen(name, "r"), closefunc = fclose;
1659		st.st_size = 0;
1660	} else {
1661		char line[BUFSIZ];
1662
1663		(void) snprintf(line, sizeof(line), cmd, name), name = line;
1664		fin = ftpd_popen(line, "r"), closefunc = ftpd_pclose;
1665		st.st_size = -1;
1666		st.st_blksize = BUFSIZ;
1667	}
1668	if (fin == NULL) {
1669		if (errno != 0) {
1670			perror_reply(550, name);
1671			if (cmd == 0) {
1672				LOGCMD("get", name);
1673			}
1674		}
1675		return;
1676	}
1677	byte_count = -1;
1678	if (cmd == 0) {
1679		if (fstat(fileno(fin), &st) < 0) {
1680			perror_reply(550, name);
1681			goto done;
1682		}
1683		if (!S_ISREG(st.st_mode)) {
1684			/*
1685			 * Never sending a raw directory is a workaround
1686			 * for buggy clients that will attempt to RETR
1687			 * a directory before listing it, e.g., Mozilla.
1688			 * Preventing a guest from getting irregular files
1689			 * is a simple security measure.
1690			 */
1691			if (S_ISDIR(st.st_mode) || guest) {
1692				reply(550, "%s: not a plain file.", name);
1693				goto done;
1694			}
1695			st.st_size = -1;
1696			/* st.st_blksize is set for all descriptor types */
1697		}
1698	}
1699	if (restart_point) {
1700		if (type == TYPE_A) {
1701			off_t i, n;
1702			int c;
1703
1704			n = restart_point;
1705			i = 0;
1706			while (i++ < n) {
1707				if ((c=getc(fin)) == EOF) {
1708					perror_reply(550, name);
1709					goto done;
1710				}
1711				if (c == '\n')
1712					i++;
1713			}
1714		} else if (lseek(fileno(fin), restart_point, L_SET) < 0) {
1715			perror_reply(550, name);
1716			goto done;
1717		}
1718	}
1719	dout = dataconn(name, st.st_size, "w");
1720	if (dout == NULL)
1721		goto done;
1722	time(&start);
1723	send_data(fin, dout, st.st_blksize, st.st_size,
1724		  restart_point == 0 && cmd == 0 && S_ISREG(st.st_mode));
1725	if (cmd == 0 && guest && stats && byte_count > 0)
1726		logxfer(name, byte_count, start);
1727	(void) fclose(dout);
1728	data = -1;
1729	pdata = -1;
1730done:
1731	if (cmd == 0)
1732		LOGBYTES("get", name, byte_count);
1733	(*closefunc)(fin);
1734}
1735
1736void
1737store(char *name, char *mode, int unique)
1738{
1739	int fd;
1740	FILE *fout, *din;
1741	int (*closefunc)(FILE *);
1742
1743	if (*mode == 'a') {		/* APPE */
1744		if (unique) {
1745			/* Programming error */
1746			syslog(LOG_ERR, "Internal: unique flag to APPE");
1747			unique = 0;
1748		}
1749		if (guest && noguestmod) {
1750			reply(550, "Appending to existing file denied.");
1751			goto err;
1752		}
1753		restart_point = 0;	/* not affected by preceding REST */
1754	}
1755	if (unique)			/* STOU overrides REST */
1756		restart_point = 0;
1757	if (guest && noguestmod) {
1758		if (restart_point) {	/* guest STOR w/REST */
1759			reply(550, "Modifying existing file denied.");
1760			goto err;
1761		} else			/* treat guest STOR as STOU */
1762			unique = 1;
1763	}
1764
1765	if (restart_point)
1766		mode = "r+";	/* so ASCII manual seek can work */
1767	if (unique) {
1768		if ((fd = guniquefd(name, &name)) < 0)
1769			goto err;
1770		fout = fdopen(fd, mode);
1771	} else
1772		fout = fopen(name, mode);
1773	closefunc = fclose;
1774	if (fout == NULL) {
1775		perror_reply(553, name);
1776		goto err;
1777	}
1778	byte_count = -1;
1779	if (restart_point) {
1780		if (type == TYPE_A) {
1781			off_t i, n;
1782			int c;
1783
1784			n = restart_point;
1785			i = 0;
1786			while (i++ < n) {
1787				if ((c=getc(fout)) == EOF) {
1788					perror_reply(550, name);
1789					goto done;
1790				}
1791				if (c == '\n')
1792					i++;
1793			}
1794			/*
1795			 * We must do this seek to "current" position
1796			 * because we are changing from reading to
1797			 * writing.
1798			 */
1799			if (fseeko(fout, 0, SEEK_CUR) < 0) {
1800				perror_reply(550, name);
1801				goto done;
1802			}
1803		} else if (lseek(fileno(fout), restart_point, L_SET) < 0) {
1804			perror_reply(550, name);
1805			goto done;
1806		}
1807	}
1808	din = dataconn(name, -1, "r");
1809	if (din == NULL)
1810		goto done;
1811	if (receive_data(din, fout) == 0) {
1812		if (unique)
1813			reply(226, "Transfer complete (unique file name:%s).",
1814			    name);
1815		else
1816			reply(226, "Transfer complete.");
1817	}
1818	(void) fclose(din);
1819	data = -1;
1820	pdata = -1;
1821done:
1822	LOGBYTES(*mode == 'a' ? "append" : "put", name, byte_count);
1823	(*closefunc)(fout);
1824	return;
1825err:
1826	LOGCMD(*mode == 'a' ? "append" : "put" , name);
1827	return;
1828}
1829
1830static FILE *
1831getdatasock(char *mode)
1832{
1833	int on = 1, s, t, tries;
1834
1835	if (data >= 0)
1836		return (fdopen(data, mode));
1837
1838	s = socket(data_dest.su_family, SOCK_STREAM, 0);
1839	if (s < 0)
1840		goto bad;
1841	if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
1842		syslog(LOG_WARNING, "data setsockopt (SO_REUSEADDR): %m");
1843	/* anchor socket to avoid multi-homing problems */
1844	data_source = ctrl_addr;
1845	data_source.su_port = htons(dataport);
1846	(void) seteuid(0);
1847	for (tries = 1; ; tries++) {
1848		/*
1849		 * We should loop here since it's possible that
1850		 * another ftpd instance has passed this point and is
1851		 * trying to open a data connection in active mode now.
1852		 * Until the other connection is opened, we'll be getting
1853		 * EADDRINUSE because no SOCK_STREAM sockets in the system
1854		 * can share both local and remote addresses, localIP:20
1855		 * and *:* in this case.
1856		 */
1857		if (bind(s, (struct sockaddr *)&data_source,
1858		    data_source.su_len) >= 0)
1859			break;
1860		if (errno != EADDRINUSE || tries > 10)
1861			goto bad;
1862		sleep(tries);
1863	}
1864	(void) seteuid(pw->pw_uid);
1865#ifdef IP_TOS
1866	if (data_source.su_family == AF_INET)
1867      {
1868	on = IPTOS_THROUGHPUT;
1869	if (setsockopt(s, IPPROTO_IP, IP_TOS, &on, sizeof(int)) < 0)
1870		syslog(LOG_WARNING, "data setsockopt (IP_TOS): %m");
1871      }
1872#endif
1873#ifdef TCP_NOPUSH
1874	/*
1875	 * Turn off push flag to keep sender TCP from sending short packets
1876	 * at the boundaries of each write().
1877	 */
1878	on = 1;
1879	if (setsockopt(s, IPPROTO_TCP, TCP_NOPUSH, &on, sizeof on) < 0)
1880		syslog(LOG_WARNING, "data setsockopt (TCP_NOPUSH): %m");
1881#endif
1882	return (fdopen(s, mode));
1883bad:
1884	/* Return the real value of errno (close may change it) */
1885	t = errno;
1886	(void) seteuid(pw->pw_uid);
1887	(void) close(s);
1888	errno = t;
1889	return (NULL);
1890}
1891
1892static FILE *
1893dataconn(char *name, off_t size, char *mode)
1894{
1895	char sizebuf[32];
1896	FILE *file;
1897	int retry = 0, tos, conerrno;
1898
1899	file_size = size;
1900	byte_count = 0;
1901	if (size != -1)
1902		(void) snprintf(sizebuf, sizeof(sizebuf),
1903				" (%jd bytes)", (intmax_t)size);
1904	else
1905		*sizebuf = '\0';
1906	if (pdata >= 0) {
1907		union sockunion from;
1908		socklen_t fromlen = ctrl_addr.su_len;
1909		int flags, s;
1910		struct timeval timeout;
1911		fd_set set;
1912
1913		FD_ZERO(&set);
1914		FD_SET(pdata, &set);
1915
1916		timeout.tv_usec = 0;
1917		timeout.tv_sec = 120;
1918
1919		/*
1920		 * Granted a socket is in the blocking I/O mode,
1921		 * accept() will block after a successful select()
1922		 * if the selected connection dies in between.
1923		 * Therefore set the non-blocking I/O flag here.
1924		 */
1925		if ((flags = fcntl(pdata, F_GETFL, 0)) == -1 ||
1926		    fcntl(pdata, F_SETFL, flags | O_NONBLOCK) == -1)
1927			goto pdata_err;
1928		if (select(pdata+1, &set, NULL, NULL, &timeout) <= 0 ||
1929		    (s = accept(pdata, (struct sockaddr *) &from, &fromlen)) < 0)
1930			goto pdata_err;
1931		(void) close(pdata);
1932		pdata = s;
1933		/*
1934		 * Unset the inherited non-blocking I/O flag
1935		 * on the child socket so stdio can work on it.
1936		 */
1937		if ((flags = fcntl(pdata, F_GETFL, 0)) == -1 ||
1938		    fcntl(pdata, F_SETFL, flags & ~O_NONBLOCK) == -1)
1939			goto pdata_err;
1940#ifdef IP_TOS
1941		if (from.su_family == AF_INET)
1942	      {
1943		tos = IPTOS_THROUGHPUT;
1944		if (setsockopt(s, IPPROTO_IP, IP_TOS, &tos, sizeof(int)) < 0)
1945			syslog(LOG_WARNING, "pdata setsockopt (IP_TOS): %m");
1946	      }
1947#endif
1948		reply(150, "Opening %s mode data connection for '%s'%s.",
1949		     type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
1950		return (fdopen(pdata, mode));
1951pdata_err:
1952		reply(425, "Can't open data connection.");
1953		(void) close(pdata);
1954		pdata = -1;
1955		return (NULL);
1956	}
1957	if (data >= 0) {
1958		reply(125, "Using existing data connection for '%s'%s.",
1959		    name, sizebuf);
1960		usedefault = 1;
1961		return (fdopen(data, mode));
1962	}
1963	if (usedefault)
1964		data_dest = his_addr;
1965	usedefault = 1;
1966	do {
1967		file = getdatasock(mode);
1968		if (file == NULL) {
1969			char hostbuf[NI_MAXHOST], portbuf[NI_MAXSERV];
1970
1971			if (getnameinfo((struct sockaddr *)&data_source,
1972				data_source.su_len,
1973				hostbuf, sizeof(hostbuf) - 1,
1974				portbuf, sizeof(portbuf) - 1,
1975				NI_NUMERICHOST|NI_NUMERICSERV))
1976					*hostbuf = *portbuf = 0;
1977			hostbuf[sizeof(hostbuf) - 1] = 0;
1978			portbuf[sizeof(portbuf) - 1] = 0;
1979			reply(425, "Can't create data socket (%s,%s): %s.",
1980				hostbuf, portbuf, strerror(errno));
1981			return (NULL);
1982		}
1983		data = fileno(file);
1984		conerrno = 0;
1985		if (connect(data, (struct sockaddr *)&data_dest,
1986		    data_dest.su_len) == 0)
1987			break;
1988		conerrno = errno;
1989		(void) fclose(file);
1990		data = -1;
1991		if (conerrno == EADDRINUSE) {
1992			sleep(swaitint);
1993			retry += swaitint;
1994		} else {
1995			break;
1996		}
1997	} while (retry <= swaitmax);
1998	if (conerrno != 0) {
1999		reply(425, "Can't build data connection: %s.",
2000			   strerror(conerrno));
2001		return (NULL);
2002	}
2003	reply(150, "Opening %s mode data connection for '%s'%s.",
2004	     type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
2005	return (file);
2006}
2007
2008/*
2009 * A helper macro to avoid code duplication
2010 * in send_data() and receive_data().
2011 *
2012 * XXX We have to block SIGURG during putc() because BSD stdio
2013 * is unable to restart interrupted write operations and hence
2014 * the entire buffer contents will be lost as soon as a write()
2015 * call indicates EINTR to stdio.
2016 */
2017#define FTPD_PUTC(ch, file, label)					\
2018	do {								\
2019		int ret;						\
2020									\
2021		do {							\
2022			START_UNSAFE;					\
2023			ret = putc((ch), (file));			\
2024			END_UNSAFE;					\
2025			CHECKOOB(return (-1))				\
2026			else if (ferror(file))				\
2027				goto label;				\
2028			clearerr(file);					\
2029		} while (ret == EOF);					\
2030	} while (0)
2031
2032/*
2033 * Tranfer the contents of "instr" to "outstr" peer using the appropriate
2034 * encapsulation of the data subject to Mode, Structure, and Type.
2035 *
2036 * NB: Form isn't handled.
2037 */
2038static int
2039send_data(FILE *instr, FILE *outstr, size_t blksize, off_t filesize, int isreg)
2040{
2041	int c, cp, filefd, netfd;
2042	char *buf;
2043
2044	STARTXFER;
2045
2046	switch (type) {
2047
2048	case TYPE_A:
2049		cp = EOF;
2050		for (;;) {
2051			c = getc(instr);
2052			CHECKOOB(return (-1))
2053			else if (c == EOF && ferror(instr))
2054				goto file_err;
2055			if (c == EOF) {
2056				if (ferror(instr)) {	/* resume after OOB */
2057					clearerr(instr);
2058					continue;
2059				}
2060				if (feof(instr))	/* EOF */
2061					break;
2062				syslog(LOG_ERR, "Internal: impossible condition"
2063						" on file after getc()");
2064				goto file_err;
2065			}
2066			if (c == '\n' && cp != '\r') {
2067				FTPD_PUTC('\r', outstr, data_err);
2068				byte_count++;
2069			}
2070			FTPD_PUTC(c, outstr, data_err);
2071			byte_count++;
2072			cp = c;
2073		}
2074#ifdef notyet	/* BSD stdio isn't ready for that */
2075		while (fflush(outstr) == EOF) {
2076			CHECKOOB(return (-1))
2077			else
2078				goto data_err;
2079			clearerr(outstr);
2080		}
2081		ENDXFER;
2082#else
2083		ENDXFER;
2084		if (fflush(outstr) == EOF)
2085			goto data_err;
2086#endif
2087		reply(226, "Transfer complete.");
2088		return (0);
2089
2090	case TYPE_I:
2091	case TYPE_L:
2092		/*
2093		 * isreg is only set if we are not doing restart and we
2094		 * are sending a regular file
2095		 */
2096		netfd = fileno(outstr);
2097		filefd = fileno(instr);
2098
2099		if (isreg) {
2100			char *msg = "Transfer complete.";
2101			off_t cnt, offset;
2102			int err;
2103
2104			cnt = offset = 0;
2105
2106			while (filesize > 0) {
2107				err = sendfile(filefd, netfd, offset, 0,
2108					       NULL, &cnt, 0);
2109				/*
2110				 * Calculate byte_count before OOB processing.
2111				 * It can be used in myoob() later.
2112				 */
2113				byte_count += cnt;
2114				offset += cnt;
2115				filesize -= cnt;
2116				CHECKOOB(return (-1))
2117				else if (err == -1) {
2118					if (errno != EINTR &&
2119					    cnt == 0 && offset == 0)
2120						goto oldway;
2121					goto data_err;
2122				}
2123				if (err == -1)	/* resume after OOB */
2124					continue;
2125				/*
2126				 * We hit the EOF prematurely.
2127				 * Perhaps the file was externally truncated.
2128				 */
2129				if (cnt == 0) {
2130					msg = "Transfer finished due to "
2131					      "premature end of file.";
2132					break;
2133				}
2134			}
2135			ENDXFER;
2136			reply(226, msg);
2137			return (0);
2138		}
2139
2140oldway:
2141		if ((buf = malloc(blksize)) == NULL) {
2142			ENDXFER;
2143			reply(451, "Ran out of memory.");
2144			return (-1);
2145		}
2146
2147		for (;;) {
2148			int cnt, len;
2149			char *bp;
2150
2151			cnt = read(filefd, buf, blksize);
2152			CHECKOOB(free(buf); return (-1))
2153			else if (cnt < 0) {
2154				free(buf);
2155				goto file_err;
2156			}
2157			if (cnt < 0)	/* resume after OOB */
2158				continue;
2159			if (cnt == 0)	/* EOF */
2160				break;
2161			for (len = cnt, bp = buf; len > 0;) {
2162				cnt = write(netfd, bp, len);
2163				CHECKOOB(free(buf); return (-1))
2164				else if (cnt < 0) {
2165					free(buf);
2166					goto data_err;
2167				}
2168				if (cnt <= 0)
2169					continue;
2170				len -= cnt;
2171				bp += cnt;
2172				byte_count += cnt;
2173			}
2174		}
2175		ENDXFER;
2176		free(buf);
2177		reply(226, "Transfer complete.");
2178		return (0);
2179	default:
2180		ENDXFER;
2181		reply(550, "Unimplemented TYPE %d in send_data.", type);
2182		return (-1);
2183	}
2184
2185data_err:
2186	ENDXFER;
2187	perror_reply(426, "Data connection");
2188	return (-1);
2189
2190file_err:
2191	ENDXFER;
2192	perror_reply(551, "Error on input file");
2193	return (-1);
2194}
2195
2196/*
2197 * Transfer data from peer to "outstr" using the appropriate encapulation of
2198 * the data subject to Mode, Structure, and Type.
2199 *
2200 * N.B.: Form isn't handled.
2201 */
2202static int
2203receive_data(FILE *instr, FILE *outstr)
2204{
2205	int c, cp;
2206	int bare_lfs = 0;
2207
2208	STARTXFER;
2209
2210	switch (type) {
2211
2212	case TYPE_I:
2213	case TYPE_L:
2214		for (;;) {
2215			int cnt, len;
2216			char *bp;
2217			char buf[BUFSIZ];
2218
2219			cnt = read(fileno(instr), buf, sizeof(buf));
2220			CHECKOOB(return (-1))
2221			else if (cnt < 0)
2222				goto data_err;
2223			if (cnt < 0)	/* resume after OOB */
2224				continue;
2225			if (cnt == 0)	/* EOF */
2226				break;
2227			for (len = cnt, bp = buf; len > 0;) {
2228				cnt = write(fileno(outstr), bp, len);
2229				CHECKOOB(return (-1))
2230				else if (cnt < 0)
2231					goto file_err;
2232				if (cnt <= 0)
2233					continue;
2234				len -= cnt;
2235				bp += cnt;
2236				byte_count += cnt;
2237			}
2238		}
2239		ENDXFER;
2240		return (0);
2241
2242	case TYPE_E:
2243		ENDXFER;
2244		reply(553, "TYPE E not implemented.");
2245		return (-1);
2246
2247	case TYPE_A:
2248		cp = EOF;
2249		for (;;) {
2250			c = getc(instr);
2251			CHECKOOB(return (-1))
2252			else if (c == EOF && ferror(instr))
2253				goto data_err;
2254			if (c == EOF && ferror(instr)) { /* resume after OOB */
2255				clearerr(instr);
2256				continue;
2257			}
2258
2259			if (cp == '\r') {
2260				if (c != '\n')
2261					FTPD_PUTC('\r', outstr, file_err);
2262			} else
2263				if (c == '\n')
2264					bare_lfs++;
2265			if (c == '\r') {
2266				byte_count++;
2267				cp = c;
2268				continue;
2269			}
2270
2271			/* Check for EOF here in order not to lose last \r. */
2272			if (c == EOF) {
2273				if (feof(instr))	/* EOF */
2274					break;
2275				syslog(LOG_ERR, "Internal: impossible condition"
2276						" on data stream after getc()");
2277				goto data_err;
2278			}
2279
2280			byte_count++;
2281			FTPD_PUTC(c, outstr, file_err);
2282			cp = c;
2283		}
2284#ifdef notyet	/* BSD stdio isn't ready for that */
2285		while (fflush(outstr) == EOF) {
2286			CHECKOOB(return (-1))
2287			else
2288				goto file_err;
2289			clearerr(outstr);
2290		}
2291		ENDXFER;
2292#else
2293		ENDXFER;
2294		if (fflush(outstr) == EOF)
2295			goto file_err;
2296#endif
2297		if (bare_lfs) {
2298			lreply(226,
2299		"WARNING! %d bare linefeeds received in ASCII mode.",
2300			    bare_lfs);
2301		(void)printf("   File may not have transferred correctly.\r\n");
2302		}
2303		return (0);
2304	default:
2305		ENDXFER;
2306		reply(550, "Unimplemented TYPE %d in receive_data.", type);
2307		return (-1);
2308	}
2309
2310data_err:
2311	ENDXFER;
2312	perror_reply(426, "Data connection");
2313	return (-1);
2314
2315file_err:
2316	ENDXFER;
2317	perror_reply(452, "Error writing to file");
2318	return (-1);
2319}
2320
2321void
2322statfilecmd(char *filename)
2323{
2324	FILE *fin;
2325	int atstart;
2326	int c, code;
2327	char line[LINE_MAX];
2328	struct stat st;
2329
2330	code = lstat(filename, &st) == 0 && S_ISDIR(st.st_mode) ? 212 : 213;
2331	(void)snprintf(line, sizeof(line), _PATH_LS " -lgA %s", filename);
2332	fin = ftpd_popen(line, "r");
2333	lreply(code, "Status of %s:", filename);
2334	atstart = 1;
2335	while ((c = getc(fin)) != EOF) {
2336		if (c == '\n') {
2337			if (ferror(stdout)){
2338				perror_reply(421, "Control connection");
2339				(void) ftpd_pclose(fin);
2340				dologout(1);
2341				/* NOTREACHED */
2342			}
2343			if (ferror(fin)) {
2344				perror_reply(551, filename);
2345				(void) ftpd_pclose(fin);
2346				return;
2347			}
2348			(void) putc('\r', stdout);
2349		}
2350		/*
2351		 * RFC 959 says neutral text should be prepended before
2352		 * a leading 3-digit number followed by whitespace, but
2353		 * many ftp clients can be confused by any leading digits,
2354		 * as a matter of fact.
2355		 */
2356		if (atstart && isdigit(c))
2357			(void) putc(' ', stdout);
2358		(void) putc(c, stdout);
2359		atstart = (c == '\n');
2360	}
2361	(void) ftpd_pclose(fin);
2362	reply(code, "End of status.");
2363}
2364
2365void
2366statcmd(void)
2367{
2368	union sockunion *su;
2369	u_char *a, *p;
2370	char hname[NI_MAXHOST];
2371	int ispassive;
2372
2373	if (hostinfo) {
2374		lreply(211, "%s FTP server status:", hostname);
2375		printf("     %s\r\n", version);
2376	} else
2377		lreply(211, "FTP server status:");
2378	printf("     Connected to %s", remotehost);
2379	if (!getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
2380			 hname, sizeof(hname) - 1, NULL, 0, NI_NUMERICHOST)) {
2381		hname[sizeof(hname) - 1] = 0;
2382		if (strcmp(hname, remotehost) != 0)
2383			printf(" (%s)", hname);
2384	}
2385	printf("\r\n");
2386	if (logged_in) {
2387		if (guest)
2388			printf("     Logged in anonymously\r\n");
2389		else
2390			printf("     Logged in as %s\r\n", pw->pw_name);
2391	} else if (askpasswd)
2392		printf("     Waiting for password\r\n");
2393	else
2394		printf("     Waiting for user name\r\n");
2395	printf("     TYPE: %s", typenames[type]);
2396	if (type == TYPE_A || type == TYPE_E)
2397		printf(", FORM: %s", formnames[form]);
2398	if (type == TYPE_L)
2399#if CHAR_BIT == 8
2400		printf(" %d", CHAR_BIT);
2401#else
2402		printf(" %d", bytesize);	/* need definition! */
2403#endif
2404	printf("; STRUcture: %s; transfer MODE: %s\r\n",
2405	    strunames[stru], modenames[mode]);
2406	if (data != -1)
2407		printf("     Data connection open\r\n");
2408	else if (pdata != -1) {
2409		ispassive = 1;
2410		su = &pasv_addr;
2411		goto printaddr;
2412	} else if (usedefault == 0) {
2413		ispassive = 0;
2414		su = &data_dest;
2415printaddr:
2416#define UC(b) (((int) b) & 0xff)
2417		if (epsvall) {
2418			printf("     EPSV only mode (EPSV ALL)\r\n");
2419			goto epsvonly;
2420		}
2421
2422		/* PORT/PASV */
2423		if (su->su_family == AF_INET) {
2424			a = (u_char *) &su->su_sin.sin_addr;
2425			p = (u_char *) &su->su_sin.sin_port;
2426			printf("     %s (%d,%d,%d,%d,%d,%d)\r\n",
2427				ispassive ? "PASV" : "PORT",
2428				UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
2429				UC(p[0]), UC(p[1]));
2430		}
2431
2432		/* LPRT/LPSV */
2433	    {
2434		int alen, af, i;
2435
2436		switch (su->su_family) {
2437		case AF_INET:
2438			a = (u_char *) &su->su_sin.sin_addr;
2439			p = (u_char *) &su->su_sin.sin_port;
2440			alen = sizeof(su->su_sin.sin_addr);
2441			af = 4;
2442			break;
2443		case AF_INET6:
2444			a = (u_char *) &su->su_sin6.sin6_addr;
2445			p = (u_char *) &su->su_sin6.sin6_port;
2446			alen = sizeof(su->su_sin6.sin6_addr);
2447			af = 6;
2448			break;
2449		default:
2450			af = 0;
2451			break;
2452		}
2453		if (af) {
2454			printf("     %s (%d,%d,", ispassive ? "LPSV" : "LPRT",
2455				af, alen);
2456			for (i = 0; i < alen; i++)
2457				printf("%d,", UC(a[i]));
2458			printf("%d,%d,%d)\r\n", 2, UC(p[0]), UC(p[1]));
2459		}
2460	    }
2461
2462epsvonly:;
2463		/* EPRT/EPSV */
2464	    {
2465		int af;
2466
2467		switch (su->su_family) {
2468		case AF_INET:
2469			af = 1;
2470			break;
2471		case AF_INET6:
2472			af = 2;
2473			break;
2474		default:
2475			af = 0;
2476			break;
2477		}
2478		if (af) {
2479			union sockunion tmp;
2480
2481			tmp = *su;
2482			if (tmp.su_family == AF_INET6)
2483				tmp.su_sin6.sin6_scope_id = 0;
2484			if (!getnameinfo((struct sockaddr *)&tmp, tmp.su_len,
2485					hname, sizeof(hname) - 1, NULL, 0,
2486					NI_NUMERICHOST)) {
2487				hname[sizeof(hname) - 1] = 0;
2488				printf("     %s |%d|%s|%d|\r\n",
2489					ispassive ? "EPSV" : "EPRT",
2490					af, hname, htons(tmp.su_port));
2491			}
2492		}
2493	    }
2494#undef UC
2495	} else
2496		printf("     No data connection\r\n");
2497	reply(211, "End of status.");
2498}
2499
2500void
2501fatalerror(char *s)
2502{
2503
2504	reply(451, "Error in server: %s", s);
2505	reply(221, "Closing connection due to server error.");
2506	dologout(0);
2507	/* NOTREACHED */
2508}
2509
2510void
2511reply(int n, const char *fmt, ...)
2512{
2513	va_list ap;
2514
2515	(void)printf("%d ", n);
2516	va_start(ap, fmt);
2517	(void)vprintf(fmt, ap);
2518	va_end(ap);
2519	(void)printf("\r\n");
2520	(void)fflush(stdout);
2521	if (ftpdebug) {
2522		syslog(LOG_DEBUG, "<--- %d ", n);
2523		va_start(ap, fmt);
2524		vsyslog(LOG_DEBUG, fmt, ap);
2525		va_end(ap);
2526	}
2527}
2528
2529void
2530lreply(int n, const char *fmt, ...)
2531{
2532	va_list ap;
2533
2534	(void)printf("%d- ", n);
2535	va_start(ap, fmt);
2536	(void)vprintf(fmt, ap);
2537	va_end(ap);
2538	(void)printf("\r\n");
2539	(void)fflush(stdout);
2540	if (ftpdebug) {
2541		syslog(LOG_DEBUG, "<--- %d- ", n);
2542		va_start(ap, fmt);
2543		vsyslog(LOG_DEBUG, fmt, ap);
2544		va_end(ap);
2545	}
2546}
2547
2548static void
2549ack(char *s)
2550{
2551
2552	reply(250, "%s command successful.", s);
2553}
2554
2555void
2556nack(char *s)
2557{
2558
2559	reply(502, "%s command not implemented.", s);
2560}
2561
2562/* ARGSUSED */
2563void
2564yyerror(char *s)
2565{
2566	char *cp;
2567
2568	if ((cp = strchr(cbuf,'\n')))
2569		*cp = '\0';
2570	reply(500, "%s: command not understood.", cbuf);
2571}
2572
2573void
2574delete(char *name)
2575{
2576	struct stat st;
2577
2578	LOGCMD("delete", name);
2579	if (lstat(name, &st) < 0) {
2580		perror_reply(550, name);
2581		return;
2582	}
2583	if (S_ISDIR(st.st_mode)) {
2584		if (rmdir(name) < 0) {
2585			perror_reply(550, name);
2586			return;
2587		}
2588		goto done;
2589	}
2590	if (guest && noguestmod) {
2591		reply(550, "Operation not permitted.");
2592		return;
2593	}
2594	if (unlink(name) < 0) {
2595		perror_reply(550, name);
2596		return;
2597	}
2598done:
2599	ack("DELE");
2600}
2601
2602void
2603cwd(char *path)
2604{
2605
2606	if (chdir(path) < 0)
2607		perror_reply(550, path);
2608	else
2609		ack("CWD");
2610}
2611
2612void
2613makedir(char *name)
2614{
2615	char *s;
2616
2617	LOGCMD("mkdir", name);
2618	if (guest && noguestmkd)
2619		reply(550, "Operation not permitted.");
2620	else if (mkdir(name, 0777) < 0)
2621		perror_reply(550, name);
2622	else {
2623		if ((s = doublequote(name)) == NULL)
2624			fatalerror("Ran out of memory.");
2625		reply(257, "\"%s\" directory created.", s);
2626		free(s);
2627	}
2628}
2629
2630void
2631removedir(char *name)
2632{
2633
2634	LOGCMD("rmdir", name);
2635	if (rmdir(name) < 0)
2636		perror_reply(550, name);
2637	else
2638		ack("RMD");
2639}
2640
2641void
2642pwd(void)
2643{
2644	char *s, path[MAXPATHLEN + 1];
2645
2646	if (getcwd(path, sizeof(path)) == NULL)
2647		perror_reply(550, "Get current directory");
2648	else {
2649		if ((s = doublequote(path)) == NULL)
2650			fatalerror("Ran out of memory.");
2651		reply(257, "\"%s\" is current directory.", s);
2652		free(s);
2653	}
2654}
2655
2656char *
2657renamefrom(char *name)
2658{
2659	struct stat st;
2660
2661	if (guest && noguestmod) {
2662		reply(550, "Operation not permitted.");
2663		return (NULL);
2664	}
2665	if (lstat(name, &st) < 0) {
2666		perror_reply(550, name);
2667		return (NULL);
2668	}
2669	reply(350, "File exists, ready for destination name.");
2670	return (name);
2671}
2672
2673void
2674renamecmd(char *from, char *to)
2675{
2676	struct stat st;
2677
2678	LOGCMD2("rename", from, to);
2679
2680	if (guest && (stat(to, &st) == 0)) {
2681		reply(550, "%s: permission denied.", to);
2682		return;
2683	}
2684
2685	if (rename(from, to) < 0)
2686		perror_reply(550, "rename");
2687	else
2688		ack("RNTO");
2689}
2690
2691static void
2692dolog(struct sockaddr *who)
2693{
2694	char who_name[NI_MAXHOST];
2695
2696	realhostname_sa(remotehost, sizeof(remotehost) - 1, who, who->sa_len);
2697	remotehost[sizeof(remotehost) - 1] = 0;
2698	if (getnameinfo(who, who->sa_len,
2699		who_name, sizeof(who_name) - 1, NULL, 0, NI_NUMERICHOST))
2700			*who_name = 0;
2701	who_name[sizeof(who_name) - 1] = 0;
2702
2703#ifdef SETPROCTITLE
2704#ifdef VIRTUAL_HOSTING
2705	if (thishost != firsthost)
2706		snprintf(proctitle, sizeof(proctitle), "%s: connected (to %s)",
2707			 remotehost, hostname);
2708	else
2709#endif
2710		snprintf(proctitle, sizeof(proctitle), "%s: connected",
2711			 remotehost);
2712	setproctitle("%s", proctitle);
2713#endif /* SETPROCTITLE */
2714
2715	if (logging) {
2716#ifdef VIRTUAL_HOSTING
2717		if (thishost != firsthost)
2718			syslog(LOG_INFO, "connection from %s (%s) to %s",
2719			       remotehost, who_name, hostname);
2720		else
2721#endif
2722			syslog(LOG_INFO, "connection from %s (%s)",
2723			       remotehost, who_name);
2724	}
2725}
2726
2727/*
2728 * Record logout in wtmp file
2729 * and exit with supplied status.
2730 */
2731void
2732dologout(int status)
2733{
2734
2735	if (logged_in && dowtmp) {
2736		(void) seteuid(0);
2737		ftpd_logwtmp(ttyline, "", NULL);
2738	}
2739	/* beware of flushing buffers after a SIGPIPE */
2740	_exit(status);
2741}
2742
2743static void
2744sigurg(int signo)
2745{
2746
2747	recvurg = 1;
2748}
2749
2750static void
2751maskurg(int flag)
2752{
2753	int oerrno;
2754	sigset_t sset;
2755
2756	if (!transflag) {
2757		syslog(LOG_ERR, "Internal: maskurg() while no transfer");
2758		return;
2759	}
2760	oerrno = errno;
2761	sigemptyset(&sset);
2762	sigaddset(&sset, SIGURG);
2763	sigprocmask(flag ? SIG_BLOCK : SIG_UNBLOCK, &sset, NULL);
2764	errno = oerrno;
2765}
2766
2767static void
2768flagxfer(int flag)
2769{
2770
2771	if (flag) {
2772		if (transflag)
2773			syslog(LOG_ERR, "Internal: flagxfer(1): "
2774					"transfer already under way");
2775		transflag = 1;
2776		maskurg(0);
2777		recvurg = 0;
2778	} else {
2779		if (!transflag)
2780			syslog(LOG_ERR, "Internal: flagxfer(0): "
2781					"no active transfer");
2782		maskurg(1);
2783		transflag = 0;
2784	}
2785}
2786
2787/*
2788 * Returns 0 if OK to resume or -1 if abort requested.
2789 */
2790static int
2791myoob(void)
2792{
2793	char *cp;
2794	int ret;
2795
2796	if (!transflag) {
2797		syslog(LOG_ERR, "Internal: myoob() while no transfer");
2798		return (0);
2799	}
2800	cp = tmpline;
2801	ret = getline(cp, 7, stdin);
2802	if (ret == -1) {
2803		reply(221, "You could at least say goodbye.");
2804		dologout(0);
2805	} else if (ret == -2) {
2806		/* Ignore truncated command. */
2807		return (0);
2808	}
2809	upper(cp);
2810	if (strcmp(cp, "ABOR\r\n") == 0) {
2811		tmpline[0] = '\0';
2812		reply(426, "Transfer aborted. Data connection closed.");
2813		reply(226, "Abort successful.");
2814		return (-1);
2815	}
2816	if (strcmp(cp, "STAT\r\n") == 0) {
2817		tmpline[0] = '\0';
2818		if (file_size != -1)
2819			reply(213, "Status: %jd of %jd bytes transferred.",
2820				   (intmax_t)byte_count, (intmax_t)file_size);
2821		else
2822			reply(213, "Status: %jd bytes transferred.",
2823				   (intmax_t)byte_count);
2824	}
2825	return (0);
2826}
2827
2828/*
2829 * Note: a response of 425 is not mentioned as a possible response to
2830 *	the PASV command in RFC959. However, it has been blessed as
2831 *	a legitimate response by Jon Postel in a telephone conversation
2832 *	with Rick Adams on 25 Jan 89.
2833 */
2834void
2835passive(void)
2836{
2837	socklen_t len;
2838	int on;
2839	char *p, *a;
2840
2841	if (pdata >= 0)		/* close old port if one set */
2842		close(pdata);
2843
2844	pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
2845	if (pdata < 0) {
2846		perror_reply(425, "Can't open passive connection");
2847		return;
2848	}
2849	on = 1;
2850	if (setsockopt(pdata, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
2851		syslog(LOG_WARNING, "pdata setsockopt (SO_REUSEADDR): %m");
2852
2853	(void) seteuid(0);
2854
2855#ifdef IP_PORTRANGE
2856	if (ctrl_addr.su_family == AF_INET) {
2857	    on = restricted_data_ports ? IP_PORTRANGE_HIGH
2858				       : IP_PORTRANGE_DEFAULT;
2859
2860	    if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE,
2861			    &on, sizeof(on)) < 0)
2862		    goto pasv_error;
2863	}
2864#endif
2865#ifdef IPV6_PORTRANGE
2866	if (ctrl_addr.su_family == AF_INET6) {
2867	    on = restricted_data_ports ? IPV6_PORTRANGE_HIGH
2868				       : IPV6_PORTRANGE_DEFAULT;
2869
2870	    if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE,
2871			    &on, sizeof(on)) < 0)
2872		    goto pasv_error;
2873	}
2874#endif
2875
2876	pasv_addr = ctrl_addr;
2877	pasv_addr.su_port = 0;
2878	if (bind(pdata, (struct sockaddr *)&pasv_addr, pasv_addr.su_len) < 0)
2879		goto pasv_error;
2880
2881	(void) seteuid(pw->pw_uid);
2882
2883	len = sizeof(pasv_addr);
2884	if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0)
2885		goto pasv_error;
2886	if (listen(pdata, 1) < 0)
2887		goto pasv_error;
2888	if (pasv_addr.su_family == AF_INET)
2889		a = (char *) &pasv_addr.su_sin.sin_addr;
2890	else if (pasv_addr.su_family == AF_INET6 &&
2891		 IN6_IS_ADDR_V4MAPPED(&pasv_addr.su_sin6.sin6_addr))
2892		a = (char *) &pasv_addr.su_sin6.sin6_addr.s6_addr[12];
2893	else
2894		goto pasv_error;
2895
2896	p = (char *) &pasv_addr.su_port;
2897
2898#define UC(b) (((int) b) & 0xff)
2899
2900	reply(227, "Entering Passive Mode (%d,%d,%d,%d,%d,%d)", UC(a[0]),
2901		UC(a[1]), UC(a[2]), UC(a[3]), UC(p[0]), UC(p[1]));
2902	return;
2903
2904pasv_error:
2905	(void) seteuid(pw->pw_uid);
2906	(void) close(pdata);
2907	pdata = -1;
2908	perror_reply(425, "Can't open passive connection");
2909	return;
2910}
2911
2912/*
2913 * Long Passive defined in RFC 1639.
2914 *     228 Entering Long Passive Mode
2915 *         (af, hal, h1, h2, h3,..., pal, p1, p2...)
2916 */
2917
2918void
2919long_passive(char *cmd, int pf)
2920{
2921	socklen_t len;
2922	int on;
2923	char *p, *a;
2924
2925	if (pdata >= 0)		/* close old port if one set */
2926		close(pdata);
2927
2928	if (pf != PF_UNSPEC) {
2929		if (ctrl_addr.su_family != pf) {
2930			switch (ctrl_addr.su_family) {
2931			case AF_INET:
2932				pf = 1;
2933				break;
2934			case AF_INET6:
2935				pf = 2;
2936				break;
2937			default:
2938				pf = 0;
2939				break;
2940			}
2941			/*
2942			 * XXX
2943			 * only EPRT/EPSV ready clients will understand this
2944			 */
2945			if (strcmp(cmd, "EPSV") == 0 && pf) {
2946				reply(522, "Network protocol mismatch, "
2947					"use (%d)", pf);
2948			} else
2949				reply(501, "Network protocol mismatch."); /*XXX*/
2950
2951			return;
2952		}
2953	}
2954
2955	pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
2956	if (pdata < 0) {
2957		perror_reply(425, "Can't open passive connection");
2958		return;
2959	}
2960	on = 1;
2961	if (setsockopt(pdata, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
2962		syslog(LOG_WARNING, "pdata setsockopt (SO_REUSEADDR): %m");
2963
2964	(void) seteuid(0);
2965
2966	pasv_addr = ctrl_addr;
2967	pasv_addr.su_port = 0;
2968	len = pasv_addr.su_len;
2969
2970#ifdef IP_PORTRANGE
2971	if (ctrl_addr.su_family == AF_INET) {
2972	    on = restricted_data_ports ? IP_PORTRANGE_HIGH
2973				       : IP_PORTRANGE_DEFAULT;
2974
2975	    if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE,
2976			    &on, sizeof(on)) < 0)
2977		    goto pasv_error;
2978	}
2979#endif
2980#ifdef IPV6_PORTRANGE
2981	if (ctrl_addr.su_family == AF_INET6) {
2982	    on = restricted_data_ports ? IPV6_PORTRANGE_HIGH
2983				       : IPV6_PORTRANGE_DEFAULT;
2984
2985	    if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE,
2986			    &on, sizeof(on)) < 0)
2987		    goto pasv_error;
2988	}
2989#endif
2990
2991	if (bind(pdata, (struct sockaddr *)&pasv_addr, len) < 0)
2992		goto pasv_error;
2993
2994	(void) seteuid(pw->pw_uid);
2995
2996	if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0)
2997		goto pasv_error;
2998	if (listen(pdata, 1) < 0)
2999		goto pasv_error;
3000
3001#define UC(b) (((int) b) & 0xff)
3002
3003	if (strcmp(cmd, "LPSV") == 0) {
3004		p = (char *)&pasv_addr.su_port;
3005		switch (pasv_addr.su_family) {
3006		case AF_INET:
3007			a = (char *) &pasv_addr.su_sin.sin_addr;
3008		v4_reply:
3009			reply(228,
3010"Entering Long Passive Mode (%d,%d,%d,%d,%d,%d,%d,%d,%d)",
3011			      4, 4, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
3012			      2, UC(p[0]), UC(p[1]));
3013			return;
3014		case AF_INET6:
3015			if (IN6_IS_ADDR_V4MAPPED(&pasv_addr.su_sin6.sin6_addr)) {
3016				a = (char *) &pasv_addr.su_sin6.sin6_addr.s6_addr[12];
3017				goto v4_reply;
3018			}
3019			a = (char *) &pasv_addr.su_sin6.sin6_addr;
3020			reply(228,
3021"Entering Long Passive Mode "
3022"(%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d)",
3023			      6, 16, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
3024			      UC(a[4]), UC(a[5]), UC(a[6]), UC(a[7]),
3025			      UC(a[8]), UC(a[9]), UC(a[10]), UC(a[11]),
3026			      UC(a[12]), UC(a[13]), UC(a[14]), UC(a[15]),
3027			      2, UC(p[0]), UC(p[1]));
3028			return;
3029		}
3030	} else if (strcmp(cmd, "EPSV") == 0) {
3031		switch (pasv_addr.su_family) {
3032		case AF_INET:
3033		case AF_INET6:
3034			reply(229, "Entering Extended Passive Mode (|||%d|)",
3035				ntohs(pasv_addr.su_port));
3036			return;
3037		}
3038	} else {
3039		/* more proper error code? */
3040	}
3041
3042pasv_error:
3043	(void) seteuid(pw->pw_uid);
3044	(void) close(pdata);
3045	pdata = -1;
3046	perror_reply(425, "Can't open passive connection");
3047	return;
3048}
3049
3050/*
3051 * Generate unique name for file with basename "local"
3052 * and open the file in order to avoid possible races.
3053 * Try "local" first, then "local.1", "local.2" etc, up to "local.99".
3054 * Return descriptor to the file, set "name" to its name.
3055 *
3056 * Generates failure reply on error.
3057 */
3058static int
3059guniquefd(char *local, char **name)
3060{
3061	static char new[MAXPATHLEN];
3062	struct stat st;
3063	char *cp;
3064	int count;
3065	int fd;
3066
3067	cp = strrchr(local, '/');
3068	if (cp)
3069		*cp = '\0';
3070	if (stat(cp ? local : ".", &st) < 0) {
3071		perror_reply(553, cp ? local : ".");
3072		return (-1);
3073	}
3074	if (cp) {
3075		/*
3076		 * Let not overwrite dirname with counter suffix.
3077		 * -4 is for /nn\0
3078		 * In this extreme case dot won't be put in front of suffix.
3079		 */
3080		if (strlen(local) > sizeof(new) - 4) {
3081			reply(553, "Pathname too long.");
3082			return (-1);
3083		}
3084		*cp = '/';
3085	}
3086	/* -4 is for the .nn<null> we put on the end below */
3087	(void) snprintf(new, sizeof(new) - 4, "%s", local);
3088	cp = new + strlen(new);
3089	/*
3090	 * Don't generate dotfile unless requested explicitly.
3091	 * This covers the case when basename gets truncated off
3092	 * by buffer size.
3093	 */
3094	if (cp > new && cp[-1] != '/')
3095		*cp++ = '.';
3096	for (count = 0; count < 100; count++) {
3097		/* At count 0 try unmodified name */
3098		if (count)
3099			(void)sprintf(cp, "%d", count);
3100		if ((fd = open(count ? new : local,
3101		    O_RDWR | O_CREAT | O_EXCL, 0666)) >= 0) {
3102			*name = count ? new : local;
3103			return (fd);
3104		}
3105		if (errno != EEXIST) {
3106			perror_reply(553, count ? new : local);
3107			return (-1);
3108		}
3109	}
3110	reply(452, "Unique file name cannot be created.");
3111	return (-1);
3112}
3113
3114/*
3115 * Format and send reply containing system error number.
3116 */
3117void
3118perror_reply(int code, char *string)
3119{
3120
3121	reply(code, "%s: %s.", string, strerror(errno));
3122}
3123
3124static char *onefile[] = {
3125	"",
3126	0
3127};
3128
3129void
3130send_file_list(char *whichf)
3131{
3132	struct stat st;
3133	DIR *dirp = NULL;
3134	struct dirent *dir;
3135	FILE *dout = NULL;
3136	char **dirlist, *dirname;
3137	int simple = 0;
3138	int freeglob = 0;
3139	glob_t gl;
3140
3141	if (strpbrk(whichf, "~{[*?") != NULL) {
3142		int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE;
3143
3144		memset(&gl, 0, sizeof(gl));
3145		gl.gl_matchc = MAXGLOBARGS;
3146		flags |= GLOB_LIMIT;
3147		freeglob = 1;
3148		if (glob(whichf, flags, 0, &gl)) {
3149			reply(550, "No matching files found.");
3150			goto out;
3151		} else if (gl.gl_pathc == 0) {
3152			errno = ENOENT;
3153			perror_reply(550, whichf);
3154			goto out;
3155		}
3156		dirlist = gl.gl_pathv;
3157	} else {
3158		onefile[0] = whichf;
3159		dirlist = onefile;
3160		simple = 1;
3161	}
3162
3163	while ((dirname = *dirlist++)) {
3164		if (stat(dirname, &st) < 0) {
3165			/*
3166			 * If user typed "ls -l", etc, and the client
3167			 * used NLST, do what the user meant.
3168			 */
3169			if (dirname[0] == '-' && *dirlist == NULL &&
3170			    dout == NULL)
3171				retrieve(_PATH_LS " %s", dirname);
3172			else
3173				perror_reply(550, whichf);
3174			goto out;
3175		}
3176
3177		if (S_ISREG(st.st_mode)) {
3178			if (dout == NULL) {
3179				dout = dataconn("file list", -1, "w");
3180				if (dout == NULL)
3181					goto out;
3182				STARTXFER;
3183			}
3184			START_UNSAFE;
3185			fprintf(dout, "%s%s\n", dirname,
3186				type == TYPE_A ? "\r" : "");
3187			END_UNSAFE;
3188			if (ferror(dout))
3189				goto data_err;
3190			byte_count += strlen(dirname) +
3191				      (type == TYPE_A ? 2 : 1);
3192			CHECKOOB(goto abrt);
3193			continue;
3194		} else if (!S_ISDIR(st.st_mode))
3195			continue;
3196
3197		if ((dirp = opendir(dirname)) == NULL)
3198			continue;
3199
3200		while ((dir = readdir(dirp)) != NULL) {
3201			char nbuf[MAXPATHLEN];
3202
3203			CHECKOOB(goto abrt);
3204
3205			if (dir->d_name[0] == '.' && dir->d_namlen == 1)
3206				continue;
3207			if (dir->d_name[0] == '.' && dir->d_name[1] == '.' &&
3208			    dir->d_namlen == 2)
3209				continue;
3210
3211			snprintf(nbuf, sizeof(nbuf),
3212				"%s/%s", dirname, dir->d_name);
3213
3214			/*
3215			 * We have to do a stat to insure it's
3216			 * not a directory or special file.
3217			 */
3218			if (simple || (stat(nbuf, &st) == 0 &&
3219			    S_ISREG(st.st_mode))) {
3220				if (dout == NULL) {
3221					dout = dataconn("file list", -1, "w");
3222					if (dout == NULL)
3223						goto out;
3224					STARTXFER;
3225				}
3226				START_UNSAFE;
3227				if (nbuf[0] == '.' && nbuf[1] == '/')
3228					fprintf(dout, "%s%s\n", &nbuf[2],
3229						type == TYPE_A ? "\r" : "");
3230				else
3231					fprintf(dout, "%s%s\n", nbuf,
3232						type == TYPE_A ? "\r" : "");
3233				END_UNSAFE;
3234				if (ferror(dout))
3235					goto data_err;
3236				byte_count += strlen(nbuf) +
3237					      (type == TYPE_A ? 2 : 1);
3238				CHECKOOB(goto abrt);
3239			}
3240		}
3241		(void) closedir(dirp);
3242		dirp = NULL;
3243	}
3244
3245	if (dout == NULL)
3246		reply(550, "No files found.");
3247	else if (ferror(dout))
3248data_err:	perror_reply(550, "Data connection");
3249	else
3250		reply(226, "Transfer complete.");
3251out:
3252	if (dout) {
3253		ENDXFER;
3254abrt:
3255		(void) fclose(dout);
3256		data = -1;
3257		pdata = -1;
3258	}
3259	if (dirp)
3260		(void) closedir(dirp);
3261	if (freeglob) {
3262		freeglob = 0;
3263		globfree(&gl);
3264	}
3265}
3266
3267void
3268reapchild(int signo)
3269{
3270	while (waitpid(-1, NULL, WNOHANG) > 0);
3271}
3272
3273#ifdef OLD_SETPROCTITLE
3274/*
3275 * Clobber argv so ps will show what we're doing.  (Stolen from sendmail.)
3276 * Warning, since this is usually started from inetd.conf, it often doesn't
3277 * have much of an environment or arglist to overwrite.
3278 */
3279void
3280setproctitle(const char *fmt, ...)
3281{
3282	int i;
3283	va_list ap;
3284	char *p, *bp, ch;
3285	char buf[LINE_MAX];
3286
3287	va_start(ap, fmt);
3288	(void)vsnprintf(buf, sizeof(buf), fmt, ap);
3289
3290	/* make ps print our process name */
3291	p = Argv[0];
3292	*p++ = '-';
3293
3294	i = strlen(buf);
3295	if (i > LastArgv - p - 2) {
3296		i = LastArgv - p - 2;
3297		buf[i] = '\0';
3298	}
3299	bp = buf;
3300	while (ch = *bp++)
3301		if (ch != '\n' && ch != '\r')
3302			*p++ = ch;
3303	while (p < LastArgv)
3304		*p++ = ' ';
3305}
3306#endif /* OLD_SETPROCTITLE */
3307
3308static void
3309appendf(char **strp, char *fmt, ...)
3310{
3311	va_list ap;
3312	char *ostr, *p;
3313
3314	va_start(ap, fmt);
3315	vasprintf(&p, fmt, ap);
3316	va_end(ap);
3317	if (p == NULL)
3318		fatalerror("Ran out of memory.");
3319	if (*strp == NULL)
3320		*strp = p;
3321	else {
3322		ostr = *strp;
3323		asprintf(strp, "%s%s", ostr, p);
3324		if (*strp == NULL)
3325			fatalerror("Ran out of memory.");
3326		free(ostr);
3327	}
3328}
3329
3330static void
3331logcmd(char *cmd, char *file1, char *file2, off_t cnt)
3332{
3333	char *msg = NULL;
3334	char wd[MAXPATHLEN + 1];
3335
3336	if (logging <= 1)
3337		return;
3338
3339	if (getcwd(wd, sizeof(wd) - 1) == NULL)
3340		strcpy(wd, strerror(errno));
3341
3342	appendf(&msg, "%s", cmd);
3343	if (file1)
3344		appendf(&msg, " %s", file1);
3345	if (file2)
3346		appendf(&msg, " %s", file2);
3347	if (cnt >= 0)
3348		appendf(&msg, " = %jd bytes", (intmax_t)cnt);
3349	appendf(&msg, " (wd: %s", wd);
3350	if (guest || dochroot)
3351		appendf(&msg, "; chrooted");
3352	appendf(&msg, ")");
3353	syslog(LOG_INFO, "%s", msg);
3354	free(msg);
3355}
3356
3357static void
3358logxfer(char *name, off_t size, time_t start)
3359{
3360	char buf[MAXPATHLEN + 1024];
3361	char path[MAXPATHLEN + 1];
3362	time_t now;
3363
3364	if (statfd >= 0) {
3365		time(&now);
3366		if (realpath(name, path) == NULL) {
3367			syslog(LOG_NOTICE, "realpath failed on %s: %m", path);
3368			return;
3369		}
3370		snprintf(buf, sizeof(buf), "%.20s!%s!%s!%s!%jd!%ld\n",
3371			ctime(&now)+4, ident, remotehost,
3372			path, (intmax_t)size,
3373			(long)(now - start + (now == start)));
3374		write(statfd, buf, strlen(buf));
3375	}
3376}
3377
3378static char *
3379doublequote(char *s)
3380{
3381	int n;
3382	char *p, *s2;
3383
3384	for (p = s, n = 0; *p; p++)
3385		if (*p == '"')
3386			n++;
3387
3388	if ((s2 = malloc(p - s + n + 1)) == NULL)
3389		return (NULL);
3390
3391	for (p = s2; *s; s++, p++) {
3392		if ((*p = *s) == '"')
3393			*(++p) = '"';
3394	}
3395	*p = '\0';
3396
3397	return (s2);
3398}
3399
3400/* setup server socket for specified address family */
3401/* if af is PF_UNSPEC more than one socket may be returned */
3402/* the returned list is dynamically allocated, so caller needs to free it */
3403static int *
3404socksetup(int af, char *bindname, const char *bindport)
3405{
3406	struct addrinfo hints, *res, *r;
3407	int error, maxs, *s, *socks;
3408	const int on = 1;
3409
3410	memset(&hints, 0, sizeof(hints));
3411	hints.ai_flags = AI_PASSIVE;
3412	hints.ai_family = af;
3413	hints.ai_socktype = SOCK_STREAM;
3414	error = getaddrinfo(bindname, bindport, &hints, &res);
3415	if (error) {
3416		syslog(LOG_ERR, "%s", gai_strerror(error));
3417		if (error == EAI_SYSTEM)
3418			syslog(LOG_ERR, "%s", strerror(errno));
3419		return NULL;
3420	}
3421
3422	/* Count max number of sockets we may open */
3423	for (maxs = 0, r = res; r; r = r->ai_next, maxs++)
3424		;
3425	socks = malloc((maxs + 1) * sizeof(int));
3426	if (!socks) {
3427		freeaddrinfo(res);
3428		syslog(LOG_ERR, "couldn't allocate memory for sockets");
3429		return NULL;
3430	}
3431
3432	*socks = 0;   /* num of sockets counter at start of array */
3433	s = socks + 1;
3434	for (r = res; r; r = r->ai_next) {
3435		*s = socket(r->ai_family, r->ai_socktype, r->ai_protocol);
3436		if (*s < 0) {
3437			syslog(LOG_DEBUG, "control socket: %m");
3438			continue;
3439		}
3440		if (setsockopt(*s, SOL_SOCKET, SO_REUSEADDR,
3441		    &on, sizeof(on)) < 0)
3442			syslog(LOG_WARNING,
3443			    "control setsockopt (SO_REUSEADDR): %m");
3444		if (r->ai_family == AF_INET6) {
3445			if (setsockopt(*s, IPPROTO_IPV6, IPV6_V6ONLY,
3446			    &on, sizeof(on)) < 0)
3447				syslog(LOG_WARNING,
3448				    "control setsockopt (IPV6_V6ONLY): %m");
3449		}
3450		if (bind(*s, r->ai_addr, r->ai_addrlen) < 0) {
3451			syslog(LOG_DEBUG, "control bind: %m");
3452			close(*s);
3453			continue;
3454		}
3455		(*socks)++;
3456		s++;
3457	}
3458
3459	if (res)
3460		freeaddrinfo(res);
3461
3462	if (*socks == 0) {
3463		syslog(LOG_ERR, "control socket: Couldn't bind to any socket");
3464		free(socks);
3465		return NULL;
3466	}
3467	return(socks);
3468}
3469