ftpd.c revision 262435
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. Neither the name of the University nor the names of its contributors
14 *    may be used to endorse or promote products derived from this software
15 *    without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#if 0
31#ifndef lint
32static char copyright[] =
33"@(#) Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994\n\
34	The Regents of the University of California.  All rights reserved.\n";
35#endif /* not lint */
36#endif
37
38#ifndef lint
39#if 0
40static char sccsid[] = "@(#)ftpd.c	8.4 (Berkeley) 4/16/94";
41#endif
42#endif /* not lint */
43
44#include <sys/cdefs.h>
45__FBSDID("$FreeBSD: stable/10/libexec/ftpd/ftpd.c 262435 2014-02-24 08:21:49Z brueffer $");
46
47/*
48 * FTP server.
49 */
50#include <sys/param.h>
51#include <sys/ioctl.h>
52#include <sys/mman.h>
53#include <sys/socket.h>
54#include <sys/stat.h>
55#include <sys/time.h>
56#include <sys/wait.h>
57
58#include <netinet/in.h>
59#include <netinet/in_systm.h>
60#include <netinet/ip.h>
61#include <netinet/tcp.h>
62
63#define	FTP_NAMES
64#include <arpa/ftp.h>
65#include <arpa/inet.h>
66#include <arpa/telnet.h>
67
68#include <ctype.h>
69#include <dirent.h>
70#include <err.h>
71#include <errno.h>
72#include <fcntl.h>
73#include <glob.h>
74#include <limits.h>
75#include <netdb.h>
76#include <pwd.h>
77#include <grp.h>
78#include <opie.h>
79#include <signal.h>
80#include <stdint.h>
81#include <stdio.h>
82#include <stdlib.h>
83#include <string.h>
84#include <syslog.h>
85#include <time.h>
86#include <unistd.h>
87#include <libutil.h>
88#ifdef	LOGIN_CAP
89#include <login_cap.h>
90#endif
91
92#ifdef USE_PAM
93#include <security/pam_appl.h>
94#endif
95
96#include "pathnames.h"
97#include "extern.h"
98
99#include <stdarg.h>
100
101static char version[] = "Version 6.00LS";
102#undef main
103
104union sockunion ctrl_addr;
105union sockunion data_source;
106union sockunion data_dest;
107union sockunion his_addr;
108union sockunion pasv_addr;
109
110int	daemon_mode;
111int	data;
112int	dataport;
113int	hostinfo = 1;	/* print host-specific info in messages */
114int	logged_in;
115struct	passwd *pw;
116char	*homedir;
117int	ftpdebug;
118int	timeout = 900;    /* timeout after 15 minutes of inactivity */
119int	maxtimeout = 7200;/* don't allow idle time to be set beyond 2 hours */
120int	logging;
121int	restricted_data_ports = 1;
122int	paranoid = 1;	  /* be extra careful about security */
123int	anon_only = 0;    /* Only anonymous ftp allowed */
124int	assumeutf8 = 0;   /* Assume that server file names are in UTF-8 */
125int	guest;
126int	dochroot;
127char	*chrootdir;
128int	dowtmp = 1;
129int	stats;
130int	statfd = -1;
131int	type;
132int	form;
133int	stru;			/* avoid C keyword */
134int	mode;
135int	usedefault = 1;		/* for data transfers */
136int	pdata = -1;		/* for passive mode */
137int	readonly = 0;		/* Server is in readonly mode.	*/
138int	noepsv = 0;		/* EPSV command is disabled.	*/
139int	noretr = 0;		/* RETR command is disabled.	*/
140int	noguestretr = 0;	/* RETR command is disabled for anon users. */
141int	noguestmkd = 0;		/* MKD command is disabled for anon users. */
142int	noguestmod = 1;		/* anon users may not modify existing files. */
143
144off_t	file_size;
145off_t	byte_count;
146#if !defined(CMASK) || CMASK == 0
147#undef CMASK
148#define CMASK 027
149#endif
150int	defumask = CMASK;		/* default umask value */
151char	tmpline[7];
152char	*hostname;
153int	epsvall = 0;
154
155#ifdef VIRTUAL_HOSTING
156char	*ftpuser;
157
158static struct ftphost {
159	struct ftphost	*next;
160	struct addrinfo *hostinfo;
161	char		*hostname;
162	char		*anonuser;
163	char		*statfile;
164	char		*welcome;
165	char		*loginmsg;
166} *thishost, *firsthost;
167
168#endif
169char	remotehost[NI_MAXHOST];
170char	*ident = NULL;
171
172static char	wtmpid[20];
173
174#ifdef USE_PAM
175static int	auth_pam(struct passwd**, const char*);
176pam_handle_t	*pamh = NULL;
177#endif
178
179static struct opie	opiedata;
180static char		opieprompt[OPIE_CHALLENGE_MAX+1];
181static int		pwok;
182
183char	*pid_file = NULL; /* means default location to pidfile(3) */
184
185/*
186 * Limit number of pathnames that glob can return.
187 * A limit of 0 indicates the number of pathnames is unlimited.
188 */
189#define MAXGLOBARGS	16384
190#
191
192/*
193 * Timeout intervals for retrying connections
194 * to hosts that don't accept PORT cmds.  This
195 * is a kludge, but given the problems with TCP...
196 */
197#define	SWAITMAX	90	/* wait at most 90 seconds */
198#define	SWAITINT	5	/* interval between retries */
199
200int	swaitmax = SWAITMAX;
201int	swaitint = SWAITINT;
202
203#ifdef SETPROCTITLE
204#ifdef OLD_SETPROCTITLE
205char	**Argv = NULL;		/* pointer to argument vector */
206char	*LastArgv = NULL;	/* end of argv */
207#endif /* OLD_SETPROCTITLE */
208char	proctitle[LINE_MAX];	/* initial part of title */
209#endif /* SETPROCTITLE */
210
211#define LOGCMD(cmd, file)		logcmd((cmd), (file), NULL, -1)
212#define LOGCMD2(cmd, file1, file2)	logcmd((cmd), (file1), (file2), -1)
213#define LOGBYTES(cmd, file, cnt)	logcmd((cmd), (file), NULL, (cnt))
214
215static	volatile sig_atomic_t recvurg;
216static	int transflag;		/* NB: for debugging only */
217
218#define STARTXFER	flagxfer(1)
219#define ENDXFER		flagxfer(0)
220
221#define START_UNSAFE	maskurg(1)
222#define END_UNSAFE	maskurg(0)
223
224/* It's OK to put an `else' clause after this macro. */
225#define CHECKOOB(action)						\
226	if (recvurg) {							\
227		recvurg = 0;						\
228		if (myoob()) {						\
229			ENDXFER;					\
230			action;						\
231		}							\
232	}
233
234#ifdef VIRTUAL_HOSTING
235static void	 inithosts(int);
236static void	 selecthost(union sockunion *);
237#endif
238static void	 ack(char *);
239static void	 sigurg(int);
240static void	 maskurg(int);
241static void	 flagxfer(int);
242static int	 myoob(void);
243static int	 checkuser(char *, char *, int, char **, int *);
244static FILE	*dataconn(char *, off_t, char *);
245static void	 dolog(struct sockaddr *);
246static void	 end_login(void);
247static FILE	*getdatasock(char *);
248static int	 guniquefd(char *, char **);
249static void	 lostconn(int);
250static void	 sigquit(int);
251static int	 receive_data(FILE *, FILE *);
252static int	 send_data(FILE *, FILE *, size_t, off_t, int);
253static struct passwd *
254		 sgetpwnam(char *);
255static char	*sgetsave(char *);
256static void	 reapchild(int);
257static void	 appendf(char **, char *, ...) __printflike(2, 3);
258static void	 logcmd(char *, char *, char *, off_t);
259static void      logxfer(char *, off_t, time_t);
260static char	*doublequote(char *);
261static int	*socksetup(int, char *, const char *);
262
263int
264main(int argc, char *argv[], char **envp)
265{
266	socklen_t addrlen;
267	int ch, on = 1, tos;
268	char *cp, line[LINE_MAX];
269	FILE *fd;
270	char	*bindname = NULL;
271	const char *bindport = "ftp";
272	int	family = AF_UNSPEC;
273	struct sigaction sa;
274
275	tzset();		/* in case no timezone database in ~ftp */
276	sigemptyset(&sa.sa_mask);
277	sa.sa_flags = SA_RESTART;
278
279#ifdef OLD_SETPROCTITLE
280	/*
281	 *  Save start and extent of argv for setproctitle.
282	 */
283	Argv = argv;
284	while (*envp)
285		envp++;
286	LastArgv = envp[-1] + strlen(envp[-1]);
287#endif /* OLD_SETPROCTITLE */
288
289	/*
290	 * Prevent diagnostic messages from appearing on stderr.
291	 * We run as a daemon or from inetd; in both cases, there's
292	 * more reason in logging to syslog.
293	 */
294	(void) freopen(_PATH_DEVNULL, "w", stderr);
295	opterr = 0;
296
297	/*
298	 * LOG_NDELAY sets up the logging connection immediately,
299	 * necessary for anonymous ftp's that chroot and can't do it later.
300	 */
301	openlog("ftpd", LOG_PID | LOG_NDELAY, LOG_FTP);
302
303	while ((ch = getopt(argc, argv,
304	                    "468a:AdDEhlmMoOp:P:rRSt:T:u:UvW")) != -1) {
305		switch (ch) {
306		case '4':
307			family = (family == AF_INET6) ? AF_UNSPEC : AF_INET;
308			break;
309
310		case '6':
311			family = (family == AF_INET) ? AF_UNSPEC : AF_INET6;
312			break;
313
314		case '8':
315			assumeutf8 = 1;
316			break;
317
318		case 'a':
319			bindname = optarg;
320			break;
321
322		case 'A':
323			anon_only = 1;
324			break;
325
326		case 'd':
327			ftpdebug++;
328			break;
329
330		case 'D':
331			daemon_mode++;
332			break;
333
334		case 'E':
335			noepsv = 1;
336			break;
337
338		case 'h':
339			hostinfo = 0;
340			break;
341
342		case 'l':
343			logging++;	/* > 1 == extra logging */
344			break;
345
346		case 'm':
347			noguestmod = 0;
348			break;
349
350		case 'M':
351			noguestmkd = 1;
352			break;
353
354		case 'o':
355			noretr = 1;
356			break;
357
358		case 'O':
359			noguestretr = 1;
360			break;
361
362		case 'p':
363			pid_file = optarg;
364			break;
365
366		case 'P':
367			bindport = optarg;
368			break;
369
370		case 'r':
371			readonly = 1;
372			break;
373
374		case 'R':
375			paranoid = 0;
376			break;
377
378		case 'S':
379			stats++;
380			break;
381
382		case 't':
383			timeout = atoi(optarg);
384			if (maxtimeout < timeout)
385				maxtimeout = timeout;
386			break;
387
388		case 'T':
389			maxtimeout = atoi(optarg);
390			if (timeout > maxtimeout)
391				timeout = maxtimeout;
392			break;
393
394		case 'u':
395		    {
396			long val = 0;
397
398			val = strtol(optarg, &optarg, 8);
399			if (*optarg != '\0' || val < 0)
400				syslog(LOG_WARNING, "bad value for -u");
401			else
402				defumask = val;
403			break;
404		    }
405		case 'U':
406			restricted_data_ports = 0;
407			break;
408
409		case 'v':
410			ftpdebug++;
411			break;
412
413		case 'W':
414			dowtmp = 0;
415			break;
416
417		default:
418			syslog(LOG_WARNING, "unknown flag -%c ignored", optopt);
419			break;
420		}
421	}
422
423	if (daemon_mode) {
424		int *ctl_sock, fd, maxfd = -1, nfds, i;
425		fd_set defreadfds, readfds;
426		pid_t pid;
427		struct pidfh *pfh;
428
429		if ((pfh = pidfile_open(pid_file, 0600, &pid)) == NULL) {
430			if (errno == EEXIST) {
431				syslog(LOG_ERR, "%s already running, pid %d",
432				       getprogname(), (int)pid);
433				exit(1);
434			}
435			syslog(LOG_WARNING, "pidfile_open: %m");
436		}
437
438		/*
439		 * Detach from parent.
440		 */
441		if (daemon(1, 1) < 0) {
442			syslog(LOG_ERR, "failed to become a daemon");
443			exit(1);
444		}
445
446		if (pfh != NULL && pidfile_write(pfh) == -1)
447			syslog(LOG_WARNING, "pidfile_write: %m");
448
449		sa.sa_handler = reapchild;
450		(void)sigaction(SIGCHLD, &sa, NULL);
451
452#ifdef VIRTUAL_HOSTING
453		inithosts(family);
454#endif
455
456		/*
457		 * Open a socket, bind it to the FTP port, and start
458		 * listening.
459		 */
460		ctl_sock = socksetup(family, bindname, bindport);
461		if (ctl_sock == NULL)
462			exit(1);
463
464		FD_ZERO(&defreadfds);
465		for (i = 1; i <= *ctl_sock; i++) {
466			FD_SET(ctl_sock[i], &defreadfds);
467			if (listen(ctl_sock[i], 32) < 0) {
468				syslog(LOG_ERR, "control listen: %m");
469				exit(1);
470			}
471			if (maxfd < ctl_sock[i])
472				maxfd = ctl_sock[i];
473		}
474
475		/*
476		 * Loop forever accepting connection requests and forking off
477		 * children to handle them.
478		 */
479		while (1) {
480			FD_COPY(&defreadfds, &readfds);
481			nfds = select(maxfd + 1, &readfds, NULL, NULL, 0);
482			if (nfds <= 0) {
483				if (nfds < 0 && errno != EINTR)
484					syslog(LOG_WARNING, "select: %m");
485				continue;
486			}
487
488			pid = -1;
489                        for (i = 1; i <= *ctl_sock; i++)
490				if (FD_ISSET(ctl_sock[i], &readfds)) {
491					addrlen = sizeof(his_addr);
492					fd = accept(ctl_sock[i],
493					    (struct sockaddr *)&his_addr,
494					    &addrlen);
495					if (fd == -1) {
496						syslog(LOG_WARNING,
497						       "accept: %m");
498						continue;
499					}
500					switch (pid = fork()) {
501					case 0:
502						/* child */
503						(void) dup2(fd, 0);
504						(void) dup2(fd, 1);
505						(void) close(fd);
506						for (i = 1; i <= *ctl_sock; i++)
507							close(ctl_sock[i]);
508						if (pfh != NULL)
509							pidfile_close(pfh);
510						goto gotchild;
511					case -1:
512						syslog(LOG_WARNING, "fork: %m");
513						/* FALLTHROUGH */
514					default:
515						close(fd);
516					}
517				}
518		}
519	} else {
520		addrlen = sizeof(his_addr);
521		if (getpeername(0, (struct sockaddr *)&his_addr, &addrlen) < 0) {
522			syslog(LOG_ERR, "getpeername (%s): %m",argv[0]);
523			exit(1);
524		}
525
526#ifdef VIRTUAL_HOSTING
527		if (his_addr.su_family == AF_INET6 &&
528		    IN6_IS_ADDR_V4MAPPED(&his_addr.su_sin6.sin6_addr))
529			family = AF_INET;
530		else
531			family = his_addr.su_family;
532		inithosts(family);
533#endif
534	}
535
536gotchild:
537	sa.sa_handler = SIG_DFL;
538	(void)sigaction(SIGCHLD, &sa, NULL);
539
540	sa.sa_handler = sigurg;
541	sa.sa_flags = 0;		/* don't restart syscalls for SIGURG */
542	(void)sigaction(SIGURG, &sa, NULL);
543
544	sigfillset(&sa.sa_mask);	/* block all signals in handler */
545	sa.sa_flags = SA_RESTART;
546	sa.sa_handler = sigquit;
547	(void)sigaction(SIGHUP, &sa, NULL);
548	(void)sigaction(SIGINT, &sa, NULL);
549	(void)sigaction(SIGQUIT, &sa, NULL);
550	(void)sigaction(SIGTERM, &sa, NULL);
551
552	sa.sa_handler = lostconn;
553	(void)sigaction(SIGPIPE, &sa, NULL);
554
555	addrlen = sizeof(ctrl_addr);
556	if (getsockname(0, (struct sockaddr *)&ctrl_addr, &addrlen) < 0) {
557		syslog(LOG_ERR, "getsockname (%s): %m",argv[0]);
558		exit(1);
559	}
560	dataport = ntohs(ctrl_addr.su_port) - 1; /* as per RFC 959 */
561#ifdef VIRTUAL_HOSTING
562	/* select our identity from virtual host table */
563	selecthost(&ctrl_addr);
564#endif
565#ifdef IP_TOS
566	if (ctrl_addr.su_family == AF_INET)
567      {
568	tos = IPTOS_LOWDELAY;
569	if (setsockopt(0, IPPROTO_IP, IP_TOS, &tos, sizeof(int)) < 0)
570		syslog(LOG_WARNING, "control setsockopt (IP_TOS): %m");
571      }
572#endif
573	/*
574	 * Disable Nagle on the control channel so that we don't have to wait
575	 * for peer's ACK before issuing our next reply.
576	 */
577	if (setsockopt(0, IPPROTO_TCP, TCP_NODELAY, &on, sizeof(on)) < 0)
578		syslog(LOG_WARNING, "control setsockopt (TCP_NODELAY): %m");
579
580	data_source.su_port = htons(ntohs(ctrl_addr.su_port) - 1);
581
582	(void)snprintf(wtmpid, sizeof(wtmpid), "%xftpd", getpid());
583
584	/* Try to handle urgent data inline */
585#ifdef SO_OOBINLINE
586	if (setsockopt(0, SOL_SOCKET, SO_OOBINLINE, &on, sizeof(on)) < 0)
587		syslog(LOG_WARNING, "control setsockopt (SO_OOBINLINE): %m");
588#endif
589
590#ifdef	F_SETOWN
591	if (fcntl(fileno(stdin), F_SETOWN, getpid()) == -1)
592		syslog(LOG_ERR, "fcntl F_SETOWN: %m");
593#endif
594	dolog((struct sockaddr *)&his_addr);
595	/*
596	 * Set up default state
597	 */
598	data = -1;
599	type = TYPE_A;
600	form = FORM_N;
601	stru = STRU_F;
602	mode = MODE_S;
603	tmpline[0] = '\0';
604
605	/* If logins are disabled, print out the message. */
606	if ((fd = fopen(_PATH_NOLOGIN,"r")) != NULL) {
607		while (fgets(line, sizeof(line), fd) != NULL) {
608			if ((cp = strchr(line, '\n')) != NULL)
609				*cp = '\0';
610			lreply(530, "%s", line);
611		}
612		(void) fflush(stdout);
613		(void) fclose(fd);
614		reply(530, "System not available.");
615		exit(0);
616	}
617#ifdef VIRTUAL_HOSTING
618	fd = fopen(thishost->welcome, "r");
619#else
620	fd = fopen(_PATH_FTPWELCOME, "r");
621#endif
622	if (fd != NULL) {
623		while (fgets(line, sizeof(line), fd) != NULL) {
624			if ((cp = strchr(line, '\n')) != NULL)
625				*cp = '\0';
626			lreply(220, "%s", line);
627		}
628		(void) fflush(stdout);
629		(void) fclose(fd);
630		/* reply(220,) must follow */
631	}
632#ifndef VIRTUAL_HOSTING
633	if ((hostname = malloc(MAXHOSTNAMELEN)) == NULL)
634		fatalerror("Ran out of memory.");
635	if (gethostname(hostname, MAXHOSTNAMELEN - 1) < 0)
636		hostname[0] = '\0';
637	hostname[MAXHOSTNAMELEN - 1] = '\0';
638#endif
639	if (hostinfo)
640		reply(220, "%s FTP server (%s) ready.", hostname, version);
641	else
642		reply(220, "FTP server ready.");
643	for (;;)
644		(void) yyparse();
645	/* NOTREACHED */
646}
647
648static void
649lostconn(int signo)
650{
651
652	if (ftpdebug)
653		syslog(LOG_DEBUG, "lost connection");
654	dologout(1);
655}
656
657static void
658sigquit(int signo)
659{
660
661	syslog(LOG_ERR, "got signal %d", signo);
662	dologout(1);
663}
664
665#ifdef VIRTUAL_HOSTING
666/*
667 * read in virtual host tables (if they exist)
668 */
669
670static void
671inithosts(int family)
672{
673	int insert;
674	size_t len;
675	FILE *fp;
676	char *cp, *mp, *line;
677	char *hostname;
678	char *vhost, *anonuser, *statfile, *welcome, *loginmsg;
679	struct ftphost *hrp, *lhrp;
680	struct addrinfo hints, *res, *ai;
681
682	/*
683	 * Fill in the default host information
684	 */
685	if ((hostname = malloc(MAXHOSTNAMELEN)) == NULL)
686		fatalerror("Ran out of memory.");
687	if (gethostname(hostname, MAXHOSTNAMELEN - 1) < 0)
688		hostname[0] = '\0';
689	hostname[MAXHOSTNAMELEN - 1] = '\0';
690	if ((hrp = malloc(sizeof(struct ftphost))) == NULL)
691		fatalerror("Ran out of memory.");
692	hrp->hostname = hostname;
693	hrp->hostinfo = NULL;
694
695	memset(&hints, 0, sizeof(hints));
696	hints.ai_flags = AI_PASSIVE;
697	hints.ai_family = family;
698	hints.ai_socktype = SOCK_STREAM;
699	if (getaddrinfo(hrp->hostname, NULL, &hints, &res) == 0)
700		hrp->hostinfo = res;
701	hrp->statfile = _PATH_FTPDSTATFILE;
702	hrp->welcome  = _PATH_FTPWELCOME;
703	hrp->loginmsg = _PATH_FTPLOGINMESG;
704	hrp->anonuser = "ftp";
705	hrp->next = NULL;
706	thishost = firsthost = lhrp = hrp;
707	if ((fp = fopen(_PATH_FTPHOSTS, "r")) != NULL) {
708		int addrsize, gothost;
709		void *addr;
710		struct hostent *hp;
711
712		while ((line = fgetln(fp, &len)) != NULL) {
713			int	i, hp_error;
714
715			/* skip comments */
716			if (line[0] == '#')
717				continue;
718			if (line[len - 1] == '\n') {
719				line[len - 1] = '\0';
720				mp = NULL;
721			} else {
722				if ((mp = malloc(len + 1)) == NULL)
723					fatalerror("Ran out of memory.");
724				memcpy(mp, line, len);
725				mp[len] = '\0';
726				line = mp;
727			}
728			cp = strtok(line, " \t");
729			/* skip empty lines */
730			if (cp == NULL)
731				goto nextline;
732			vhost = cp;
733
734			/* set defaults */
735			anonuser = "ftp";
736			statfile = _PATH_FTPDSTATFILE;
737			welcome  = _PATH_FTPWELCOME;
738			loginmsg = _PATH_FTPLOGINMESG;
739
740			/*
741			 * Preparse the line so we can use its info
742			 * for all the addresses associated with
743			 * the virtual host name.
744			 * Field 0, the virtual host name, is special:
745			 * it's already parsed off and will be strdup'ed
746			 * later, after we know its canonical form.
747			 */
748			for (i = 1; i < 5 && (cp = strtok(NULL, " \t")); i++)
749				if (*cp != '-' && (cp = strdup(cp)))
750					switch (i) {
751					case 1:	/* anon user permissions */
752						anonuser = cp;
753						break;
754					case 2: /* statistics file */
755						statfile = cp;
756						break;
757					case 3: /* welcome message */
758						welcome  = cp;
759						break;
760					case 4: /* login message */
761						loginmsg = cp;
762						break;
763					default: /* programming error */
764						abort();
765						/* NOTREACHED */
766					}
767
768			hints.ai_flags = AI_PASSIVE;
769			hints.ai_family = family;
770			hints.ai_socktype = SOCK_STREAM;
771			if (getaddrinfo(vhost, NULL, &hints, &res) != 0)
772				goto nextline;
773			for (ai = res; ai != NULL && ai->ai_addr != NULL;
774			     ai = ai->ai_next) {
775
776			gothost = 0;
777			for (hrp = firsthost; hrp != NULL; hrp = hrp->next) {
778				struct addrinfo *hi;
779
780				for (hi = hrp->hostinfo; hi != NULL;
781				     hi = hi->ai_next)
782					if (hi->ai_addrlen == ai->ai_addrlen &&
783					    memcmp(hi->ai_addr,
784						   ai->ai_addr,
785						   ai->ai_addr->sa_len) == 0) {
786						gothost++;
787						break;
788					}
789				if (gothost)
790					break;
791			}
792			if (hrp == NULL) {
793				if ((hrp = malloc(sizeof(struct ftphost))) == NULL)
794					goto nextline;
795				hrp->hostname = NULL;
796				insert = 1;
797			} else {
798				if (hrp->hostinfo && hrp->hostinfo != res)
799					freeaddrinfo(hrp->hostinfo);
800				insert = 0; /* host already in the chain */
801			}
802			hrp->hostinfo = res;
803
804			/*
805			 * determine hostname to use.
806			 * force defined name if there is a valid alias
807			 * otherwise fallback to primary hostname
808			 */
809			/* XXX: getaddrinfo() can't do alias check */
810			switch(hrp->hostinfo->ai_family) {
811			case AF_INET:
812				addr = &((struct sockaddr_in *)hrp->hostinfo->ai_addr)->sin_addr;
813				addrsize = sizeof(struct in_addr);
814				break;
815			case AF_INET6:
816				addr = &((struct sockaddr_in6 *)hrp->hostinfo->ai_addr)->sin6_addr;
817				addrsize = sizeof(struct in6_addr);
818				break;
819			default:
820				/* should not reach here */
821				freeaddrinfo(hrp->hostinfo);
822				if (insert)
823					free(hrp); /*not in chain, can free*/
824				else
825					hrp->hostinfo = NULL; /*mark as blank*/
826				goto nextline;
827				/* NOTREACHED */
828			}
829			if ((hp = getipnodebyaddr(addr, addrsize,
830						  hrp->hostinfo->ai_family,
831						  &hp_error)) != NULL) {
832				if (strcmp(vhost, hp->h_name) != 0) {
833					if (hp->h_aliases == NULL)
834						vhost = hp->h_name;
835					else {
836						i = 0;
837						while (hp->h_aliases[i] &&
838						       strcmp(vhost, hp->h_aliases[i]) != 0)
839							++i;
840						if (hp->h_aliases[i] == NULL)
841							vhost = hp->h_name;
842					}
843				}
844			}
845			if (hrp->hostname &&
846			    strcmp(hrp->hostname, vhost) != 0) {
847				free(hrp->hostname);
848				hrp->hostname = NULL;
849			}
850			if (hrp->hostname == NULL &&
851			    (hrp->hostname = strdup(vhost)) == NULL) {
852				freeaddrinfo(hrp->hostinfo);
853				hrp->hostinfo = NULL; /* mark as blank */
854				if (hp)
855					freehostent(hp);
856				goto nextline;
857			}
858			hrp->anonuser = anonuser;
859			hrp->statfile = statfile;
860			hrp->welcome  = welcome;
861			hrp->loginmsg = loginmsg;
862			if (insert) {
863				hrp->next  = NULL;
864				lhrp->next = hrp;
865				lhrp = hrp;
866			}
867			if (hp)
868				freehostent(hp);
869		      }
870nextline:
871			if (mp)
872				free(mp);
873		}
874		(void) fclose(fp);
875	}
876}
877
878static void
879selecthost(union sockunion *su)
880{
881	struct ftphost	*hrp;
882	u_int16_t port;
883#ifdef INET6
884	struct in6_addr *mapped_in6 = NULL;
885#endif
886	struct addrinfo *hi;
887
888#ifdef INET6
889	/*
890	 * XXX IPv4 mapped IPv6 addr consideraton,
891	 * specified in rfc2373.
892	 */
893	if (su->su_family == AF_INET6 &&
894	    IN6_IS_ADDR_V4MAPPED(&su->su_sin6.sin6_addr))
895		mapped_in6 = &su->su_sin6.sin6_addr;
896#endif
897
898	hrp = thishost = firsthost;	/* default */
899	port = su->su_port;
900	su->su_port = 0;
901	while (hrp != NULL) {
902	    for (hi = hrp->hostinfo; hi != NULL; hi = hi->ai_next) {
903		if (memcmp(su, hi->ai_addr, hi->ai_addrlen) == 0) {
904			thishost = hrp;
905			goto found;
906		}
907#ifdef INET6
908		/* XXX IPv4 mapped IPv6 addr consideraton */
909		if (hi->ai_addr->sa_family == AF_INET && mapped_in6 != NULL &&
910		    (memcmp(&mapped_in6->s6_addr[12],
911			    &((struct sockaddr_in *)hi->ai_addr)->sin_addr,
912			    sizeof(struct in_addr)) == 0)) {
913			thishost = hrp;
914			goto found;
915		}
916#endif
917	    }
918	    hrp = hrp->next;
919	}
920found:
921	su->su_port = port;
922	/* setup static variables as appropriate */
923	hostname = thishost->hostname;
924	ftpuser = thishost->anonuser;
925}
926#endif
927
928/*
929 * Helper function for sgetpwnam().
930 */
931static char *
932sgetsave(char *s)
933{
934	char *new = malloc(strlen(s) + 1);
935
936	if (new == NULL) {
937		reply(421, "Ran out of memory.");
938		dologout(1);
939		/* NOTREACHED */
940	}
941	(void) strcpy(new, s);
942	return (new);
943}
944
945/*
946 * Save the result of a getpwnam.  Used for USER command, since
947 * the data returned must not be clobbered by any other command
948 * (e.g., globbing).
949 * NB: The data returned by sgetpwnam() will remain valid until
950 * the next call to this function.  Its difference from getpwnam()
951 * is that sgetpwnam() is known to be called from ftpd code only.
952 */
953static struct passwd *
954sgetpwnam(char *name)
955{
956	static struct passwd save;
957	struct passwd *p;
958
959	if ((p = getpwnam(name)) == NULL)
960		return (p);
961	if (save.pw_name) {
962		free(save.pw_name);
963		free(save.pw_passwd);
964		free(save.pw_class);
965		free(save.pw_gecos);
966		free(save.pw_dir);
967		free(save.pw_shell);
968	}
969	save = *p;
970	save.pw_name = sgetsave(p->pw_name);
971	save.pw_passwd = sgetsave(p->pw_passwd);
972	save.pw_class = sgetsave(p->pw_class);
973	save.pw_gecos = sgetsave(p->pw_gecos);
974	save.pw_dir = sgetsave(p->pw_dir);
975	save.pw_shell = sgetsave(p->pw_shell);
976	return (&save);
977}
978
979static int login_attempts;	/* number of failed login attempts */
980static int askpasswd;		/* had user command, ask for passwd */
981static char curname[MAXLOGNAME];	/* current USER name */
982
983/*
984 * USER command.
985 * Sets global passwd pointer pw if named account exists and is acceptable;
986 * sets askpasswd if a PASS command is expected.  If logged in previously,
987 * need to reset state.  If name is "ftp" or "anonymous", the name is not in
988 * _PATH_FTPUSERS, and ftp account exists, set guest and pw, then just return.
989 * If account doesn't exist, ask for passwd anyway.  Otherwise, check user
990 * requesting login privileges.  Disallow anyone who does not have a standard
991 * shell as returned by getusershell().  Disallow anyone mentioned in the file
992 * _PATH_FTPUSERS to allow people such as root and uucp to be avoided.
993 */
994void
995user(char *name)
996{
997	int ecode;
998	char *cp, *shell;
999
1000	if (logged_in) {
1001		if (guest) {
1002			reply(530, "Can't change user from guest login.");
1003			return;
1004		} else if (dochroot) {
1005			reply(530, "Can't change user from chroot user.");
1006			return;
1007		}
1008		end_login();
1009	}
1010
1011	guest = 0;
1012#ifdef VIRTUAL_HOSTING
1013	pw = sgetpwnam(thishost->anonuser);
1014#else
1015	pw = sgetpwnam("ftp");
1016#endif
1017	if (strcmp(name, "ftp") == 0 || strcmp(name, "anonymous") == 0) {
1018		if (checkuser(_PATH_FTPUSERS, "ftp", 0, NULL, &ecode) ||
1019		    (ecode != 0 && ecode != ENOENT))
1020			reply(530, "User %s access denied.", name);
1021		else if (checkuser(_PATH_FTPUSERS, "anonymous", 0, NULL, &ecode) ||
1022		    (ecode != 0 && ecode != ENOENT))
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 ||
1051		    (checkuser(_PATH_FTPUSERS, name, 1, NULL, &ecode) ||
1052		    (ecode != 0 && ecode != ENOENT))) {
1053			reply(530, "User %s access denied.", name);
1054			if (logging)
1055				syslog(LOG_NOTICE,
1056				    "FTP LOGIN REFUSED FROM %s, %s",
1057				    remotehost, name);
1058			pw = NULL;
1059			return;
1060		}
1061	}
1062	if (logging)
1063		strncpy(curname, name, sizeof(curname)-1);
1064
1065	pwok = 0;
1066#ifdef USE_PAM
1067	/* XXX Kluge! The conversation mechanism needs to be fixed. */
1068#endif
1069	if (opiechallenge(&opiedata, name, opieprompt) == 0) {
1070		pwok = (pw != NULL) &&
1071		       opieaccessfile(remotehost) &&
1072		       opiealways(pw->pw_dir);
1073		reply(331, "Response to %s %s for %s.",
1074		      opieprompt, pwok ? "requested" : "required", name);
1075	} else {
1076		pwok = 1;
1077		reply(331, "Password required for %s.", name);
1078	}
1079	askpasswd = 1;
1080	/*
1081	 * Delay before reading passwd after first failed
1082	 * attempt to slow down passwd-guessing programs.
1083	 */
1084	if (login_attempts)
1085		sleep(login_attempts);
1086}
1087
1088/*
1089 * Check if a user is in the file "fname",
1090 * return a pointer to a malloc'd string with the rest
1091 * of the matching line in "residue" if not NULL.
1092 */
1093static int
1094checkuser(char *fname, char *name, int pwset, char **residue, int *ecode)
1095{
1096	FILE *fd;
1097	int found = 0;
1098	size_t len;
1099	char *line, *mp, *p;
1100
1101	if (ecode != NULL)
1102		*ecode = 0;
1103	if ((fd = fopen(fname, "r")) != NULL) {
1104		while (!found && (line = fgetln(fd, &len)) != NULL) {
1105			/* skip comments */
1106			if (line[0] == '#')
1107				continue;
1108			if (line[len - 1] == '\n') {
1109				line[len - 1] = '\0';
1110				mp = NULL;
1111			} else {
1112				if ((mp = malloc(len + 1)) == NULL)
1113					fatalerror("Ran out of memory.");
1114				memcpy(mp, line, len);
1115				mp[len] = '\0';
1116				line = mp;
1117			}
1118			/* avoid possible leading and trailing whitespace */
1119			p = strtok(line, " \t");
1120			/* skip empty lines */
1121			if (p == NULL)
1122				goto nextline;
1123			/*
1124			 * if first chr is '@', check group membership
1125			 */
1126			if (p[0] == '@') {
1127				int i = 0;
1128				struct group *grp;
1129
1130				if (p[1] == '\0') /* single @ matches anyone */
1131					found = 1;
1132				else {
1133					if ((grp = getgrnam(p+1)) == NULL)
1134						goto nextline;
1135					/*
1136					 * Check user's default group
1137					 */
1138					if (pwset && grp->gr_gid == pw->pw_gid)
1139						found = 1;
1140					/*
1141					 * Check supplementary groups
1142					 */
1143					while (!found && grp->gr_mem[i])
1144						found = strcmp(name,
1145							grp->gr_mem[i++])
1146							== 0;
1147				}
1148			}
1149			/*
1150			 * Otherwise, just check for username match
1151			 */
1152			else
1153				found = strcmp(p, name) == 0;
1154			/*
1155			 * Save the rest of line to "residue" if matched
1156			 */
1157			if (found && residue) {
1158				if ((p = strtok(NULL, "")) != NULL)
1159					p += strspn(p, " \t");
1160				if (p && *p) {
1161				 	if ((*residue = strdup(p)) == NULL)
1162						fatalerror("Ran out of memory.");
1163				} else
1164					*residue = NULL;
1165			}
1166nextline:
1167			if (mp)
1168				free(mp);
1169		}
1170		(void) fclose(fd);
1171	} else if (ecode != NULL)
1172		*ecode = errno;
1173	return (found);
1174}
1175
1176/*
1177 * Terminate login as previous user, if any, resetting state;
1178 * used when USER command is given or login fails.
1179 */
1180static void
1181end_login(void)
1182{
1183#ifdef USE_PAM
1184	int e;
1185#endif
1186
1187	(void) seteuid(0);
1188	if (logged_in && dowtmp)
1189		ftpd_logwtmp(wtmpid, NULL, NULL);
1190	pw = NULL;
1191#ifdef	LOGIN_CAP
1192	setusercontext(NULL, getpwuid(0), 0, LOGIN_SETALL & ~(LOGIN_SETLOGIN |
1193		       LOGIN_SETUSER | LOGIN_SETGROUP | LOGIN_SETPATH |
1194		       LOGIN_SETENV));
1195#endif
1196#ifdef USE_PAM
1197	if (pamh) {
1198		if ((e = pam_setcred(pamh, PAM_DELETE_CRED)) != PAM_SUCCESS)
1199			syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, e));
1200		if ((e = pam_close_session(pamh,0)) != PAM_SUCCESS)
1201			syslog(LOG_ERR, "pam_close_session: %s", pam_strerror(pamh, e));
1202		if ((e = pam_end(pamh, e)) != PAM_SUCCESS)
1203			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1204		pamh = NULL;
1205	}
1206#endif
1207	logged_in = 0;
1208	guest = 0;
1209	dochroot = 0;
1210}
1211
1212#ifdef USE_PAM
1213
1214/*
1215 * the following code is stolen from imap-uw PAM authentication module and
1216 * login.c
1217 */
1218#define COPY_STRING(s) (s ? strdup(s) : NULL)
1219
1220struct cred_t {
1221	const char *uname;		/* user name */
1222	const char *pass;		/* password */
1223};
1224typedef struct cred_t cred_t;
1225
1226static int
1227auth_conv(int num_msg, const struct pam_message **msg,
1228	  struct pam_response **resp, void *appdata)
1229{
1230	int i;
1231	cred_t *cred = (cred_t *) appdata;
1232	struct pam_response *reply;
1233
1234	reply = calloc(num_msg, sizeof *reply);
1235	if (reply == NULL)
1236		return PAM_BUF_ERR;
1237
1238	for (i = 0; i < num_msg; i++) {
1239		switch (msg[i]->msg_style) {
1240		case PAM_PROMPT_ECHO_ON:	/* assume want user name */
1241			reply[i].resp_retcode = PAM_SUCCESS;
1242			reply[i].resp = COPY_STRING(cred->uname);
1243			/* PAM frees resp. */
1244			break;
1245		case PAM_PROMPT_ECHO_OFF:	/* assume want password */
1246			reply[i].resp_retcode = PAM_SUCCESS;
1247			reply[i].resp = COPY_STRING(cred->pass);
1248			/* PAM frees resp. */
1249			break;
1250		case PAM_TEXT_INFO:
1251		case PAM_ERROR_MSG:
1252			reply[i].resp_retcode = PAM_SUCCESS;
1253			reply[i].resp = NULL;
1254			break;
1255		default:			/* unknown message style */
1256			free(reply);
1257			return PAM_CONV_ERR;
1258		}
1259	}
1260
1261	*resp = reply;
1262	return PAM_SUCCESS;
1263}
1264
1265/*
1266 * Attempt to authenticate the user using PAM.  Returns 0 if the user is
1267 * authenticated, or 1 if not authenticated.  If some sort of PAM system
1268 * error occurs (e.g., the "/etc/pam.conf" file is missing) then this
1269 * function returns -1.  This can be used as an indication that we should
1270 * fall back to a different authentication mechanism.
1271 */
1272static int
1273auth_pam(struct passwd **ppw, const char *pass)
1274{
1275	const char *tmpl_user;
1276	const void *item;
1277	int rval;
1278	int e;
1279	cred_t auth_cred = { (*ppw)->pw_name, pass };
1280	struct pam_conv conv = { &auth_conv, &auth_cred };
1281
1282	e = pam_start("ftpd", (*ppw)->pw_name, &conv, &pamh);
1283	if (e != PAM_SUCCESS) {
1284		/*
1285		 * In OpenPAM, it's OK to pass NULL to pam_strerror()
1286		 * if context creation has failed in the first place.
1287		 */
1288		syslog(LOG_ERR, "pam_start: %s", pam_strerror(NULL, e));
1289		return -1;
1290	}
1291
1292	e = pam_set_item(pamh, PAM_RHOST, remotehost);
1293	if (e != PAM_SUCCESS) {
1294		syslog(LOG_ERR, "pam_set_item(PAM_RHOST): %s",
1295			pam_strerror(pamh, e));
1296		if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
1297			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1298		}
1299		pamh = NULL;
1300		return -1;
1301	}
1302
1303	e = pam_authenticate(pamh, 0);
1304	switch (e) {
1305	case PAM_SUCCESS:
1306		/*
1307		 * With PAM we support the concept of a "template"
1308		 * user.  The user enters a login name which is
1309		 * authenticated by PAM, usually via a remote service
1310		 * such as RADIUS or TACACS+.  If authentication
1311		 * succeeds, a different but related "template" name
1312		 * is used for setting the credentials, shell, and
1313		 * home directory.  The name the user enters need only
1314		 * exist on the remote authentication server, but the
1315		 * template name must be present in the local password
1316		 * database.
1317		 *
1318		 * This is supported by two various mechanisms in the
1319		 * individual modules.  However, from the application's
1320		 * point of view, the template user is always passed
1321		 * back as a changed value of the PAM_USER item.
1322		 */
1323		if ((e = pam_get_item(pamh, PAM_USER, &item)) ==
1324		    PAM_SUCCESS) {
1325			tmpl_user = (const char *) item;
1326			if (strcmp((*ppw)->pw_name, tmpl_user) != 0)
1327				*ppw = getpwnam(tmpl_user);
1328		} else
1329			syslog(LOG_ERR, "Couldn't get PAM_USER: %s",
1330			    pam_strerror(pamh, e));
1331		rval = 0;
1332		break;
1333
1334	case PAM_AUTH_ERR:
1335	case PAM_USER_UNKNOWN:
1336	case PAM_MAXTRIES:
1337		rval = 1;
1338		break;
1339
1340	default:
1341		syslog(LOG_ERR, "pam_authenticate: %s", pam_strerror(pamh, e));
1342		rval = -1;
1343		break;
1344	}
1345
1346	if (rval == 0) {
1347		e = pam_acct_mgmt(pamh, 0);
1348		if (e != PAM_SUCCESS) {
1349			syslog(LOG_ERR, "pam_acct_mgmt: %s",
1350						pam_strerror(pamh, e));
1351			rval = 1;
1352		}
1353	}
1354
1355	if (rval != 0) {
1356		if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
1357			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
1358		}
1359		pamh = NULL;
1360	}
1361	return rval;
1362}
1363
1364#endif /* USE_PAM */
1365
1366void
1367pass(char *passwd)
1368{
1369	int rval, ecode;
1370	FILE *fd;
1371#ifdef	LOGIN_CAP
1372	login_cap_t *lc = NULL;
1373#endif
1374#ifdef USE_PAM
1375	int e;
1376#endif
1377	char *residue = NULL;
1378	char *xpasswd;
1379
1380	if (logged_in || askpasswd == 0) {
1381		reply(503, "Login with USER first.");
1382		return;
1383	}
1384	askpasswd = 0;
1385	if (!guest) {		/* "ftp" is only account allowed no password */
1386		if (pw == NULL) {
1387			rval = 1;	/* failure below */
1388			goto skip;
1389		}
1390#ifdef USE_PAM
1391		rval = auth_pam(&pw, passwd);
1392		if (rval >= 0) {
1393			opieunlock();
1394			goto skip;
1395		}
1396#endif
1397		if (opieverify(&opiedata, passwd) == 0)
1398			xpasswd = pw->pw_passwd;
1399		else if (pwok) {
1400			xpasswd = crypt(passwd, pw->pw_passwd);
1401			if (passwd[0] == '\0' && pw->pw_passwd[0] != '\0')
1402				xpasswd = ":";
1403		} else {
1404			rval = 1;
1405			goto skip;
1406		}
1407		rval = strcmp(pw->pw_passwd, xpasswd);
1408		if (pw->pw_expire && time(NULL) >= pw->pw_expire)
1409			rval = 1;	/* failure */
1410skip:
1411		/*
1412		 * If rval == 1, the user failed the authentication check
1413		 * above.  If rval == 0, either PAM or local authentication
1414		 * succeeded.
1415		 */
1416		if (rval) {
1417			reply(530, "Login incorrect.");
1418			if (logging) {
1419				syslog(LOG_NOTICE,
1420				    "FTP LOGIN FAILED FROM %s",
1421				    remotehost);
1422				syslog(LOG_AUTHPRIV | LOG_NOTICE,
1423				    "FTP LOGIN FAILED FROM %s, %s",
1424				    remotehost, curname);
1425			}
1426			pw = NULL;
1427			if (login_attempts++ >= 5) {
1428				syslog(LOG_NOTICE,
1429				    "repeated login failures from %s",
1430				    remotehost);
1431				exit(0);
1432			}
1433			return;
1434		}
1435	}
1436	login_attempts = 0;		/* this time successful */
1437	if (setegid(pw->pw_gid) < 0) {
1438		reply(550, "Can't set gid.");
1439		return;
1440	}
1441	/* May be overridden by login.conf */
1442	(void) umask(defumask);
1443#ifdef	LOGIN_CAP
1444	if ((lc = login_getpwclass(pw)) != NULL) {
1445		char	remote_ip[NI_MAXHOST];
1446
1447		if (getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
1448			remote_ip, sizeof(remote_ip) - 1, NULL, 0,
1449			NI_NUMERICHOST))
1450				*remote_ip = 0;
1451		remote_ip[sizeof(remote_ip) - 1] = 0;
1452		if (!auth_hostok(lc, remotehost, remote_ip)) {
1453			syslog(LOG_INFO|LOG_AUTH,
1454			    "FTP LOGIN FAILED (HOST) as %s: permission denied.",
1455			    pw->pw_name);
1456			reply(530, "Permission denied.");
1457			pw = NULL;
1458			return;
1459		}
1460		if (!auth_timeok(lc, time(NULL))) {
1461			reply(530, "Login not available right now.");
1462			pw = NULL;
1463			return;
1464		}
1465	}
1466	setusercontext(lc, pw, 0, LOGIN_SETALL &
1467		       ~(LOGIN_SETUSER | LOGIN_SETPATH | LOGIN_SETENV));
1468#else
1469	setlogin(pw->pw_name);
1470	(void) initgroups(pw->pw_name, pw->pw_gid);
1471#endif
1472
1473#ifdef USE_PAM
1474	if (pamh) {
1475		if ((e = pam_open_session(pamh, 0)) != PAM_SUCCESS) {
1476			syslog(LOG_ERR, "pam_open_session: %s", pam_strerror(pamh, e));
1477		} else if ((e = pam_setcred(pamh, PAM_ESTABLISH_CRED)) != PAM_SUCCESS) {
1478			syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, e));
1479		}
1480	}
1481#endif
1482
1483	dochroot =
1484		checkuser(_PATH_FTPCHROOT, pw->pw_name, 1, &residue, &ecode)
1485#ifdef	LOGIN_CAP	/* Allow login.conf configuration as well */
1486		|| login_getcapbool(lc, "ftp-chroot", 0)
1487#endif
1488	;
1489	/*
1490	 * It is possible that checkuser() failed to open the chroot file.
1491	 * If this is the case, report that logins are un-available, since we
1492	 * have no way of checking whether or not the user should be chrooted.
1493	 * We ignore ENOENT since it is not required that this file be present.
1494	 */
1495	if (ecode != 0 && ecode != ENOENT) {
1496		reply(530, "Login not available right now.");
1497		return;
1498	}
1499	chrootdir = NULL;
1500
1501	/* Disable wtmp logging when chrooting. */
1502	if (dochroot || guest)
1503		dowtmp = 0;
1504	if (dowtmp)
1505		ftpd_logwtmp(wtmpid, pw->pw_name,
1506		    (struct sockaddr *)&his_addr);
1507	logged_in = 1;
1508
1509	if (guest && stats && statfd < 0)
1510#ifdef VIRTUAL_HOSTING
1511		statfd = open(thishost->statfile, O_WRONLY|O_APPEND);
1512#else
1513		statfd = open(_PATH_FTPDSTATFILE, O_WRONLY|O_APPEND);
1514#endif
1515		if (statfd < 0)
1516			stats = 0;
1517
1518	/*
1519	 * For a chrooted local user,
1520	 * a) see whether ftpchroot(5) specifies a chroot directory,
1521	 * b) extract the directory pathname from the line,
1522	 * c) expand it to the absolute pathname if necessary.
1523	 */
1524	if (dochroot && residue &&
1525	    (chrootdir = strtok(residue, " \t")) != NULL) {
1526		if (chrootdir[0] != '/')
1527			asprintf(&chrootdir, "%s/%s", pw->pw_dir, chrootdir);
1528		else
1529			chrootdir = strdup(chrootdir); /* make it permanent */
1530		if (chrootdir == NULL)
1531			fatalerror("Ran out of memory.");
1532	}
1533	if (guest || dochroot) {
1534		/*
1535		 * If no chroot directory set yet, use the login directory.
1536		 * Copy it so it can be modified while pw->pw_dir stays intact.
1537		 */
1538		if (chrootdir == NULL &&
1539		    (chrootdir = strdup(pw->pw_dir)) == NULL)
1540			fatalerror("Ran out of memory.");
1541		/*
1542		 * Check for the "/chroot/./home" syntax,
1543		 * separate the chroot and home directory pathnames.
1544		 */
1545		if ((homedir = strstr(chrootdir, "/./")) != NULL) {
1546			*(homedir++) = '\0';	/* wipe '/' */
1547			homedir++;		/* skip '.' */
1548		} else {
1549			/*
1550			 * We MUST do a chdir() after the chroot. Otherwise
1551			 * the old current directory will be accessible as "."
1552			 * outside the new root!
1553			 */
1554			homedir = "/";
1555		}
1556		/*
1557		 * Finally, do chroot()
1558		 */
1559		if (chroot(chrootdir) < 0) {
1560			reply(550, "Can't change root.");
1561			goto bad;
1562		}
1563		__FreeBSD_libc_enter_restricted_mode();
1564	} else	/* real user w/o chroot */
1565		homedir = pw->pw_dir;
1566	/*
1567	 * Set euid *before* doing chdir() so
1568	 * a) the user won't be carried to a directory that he couldn't reach
1569	 *    on his own due to no permission to upper path components,
1570	 * b) NFS mounted homedirs w/restrictive permissions will be accessible
1571	 *    (uid 0 has no root power over NFS if not mapped explicitly.)
1572	 */
1573	if (seteuid(pw->pw_uid) < 0) {
1574		reply(550, "Can't set uid.");
1575		goto bad;
1576	}
1577	if (chdir(homedir) < 0) {
1578		if (guest || dochroot) {
1579			reply(550, "Can't change to base directory.");
1580			goto bad;
1581		} else {
1582			if (chdir("/") < 0) {
1583				reply(550, "Root is inaccessible.");
1584				goto bad;
1585			}
1586			lreply(230, "No directory! Logging in with home=/.");
1587		}
1588	}
1589
1590	/*
1591	 * Display a login message, if it exists.
1592	 * N.B. reply(230,) must follow the message.
1593	 */
1594#ifdef VIRTUAL_HOSTING
1595	fd = fopen(thishost->loginmsg, "r");
1596#else
1597	fd = fopen(_PATH_FTPLOGINMESG, "r");
1598#endif
1599	if (fd != NULL) {
1600		char *cp, line[LINE_MAX];
1601
1602		while (fgets(line, sizeof(line), fd) != NULL) {
1603			if ((cp = strchr(line, '\n')) != NULL)
1604				*cp = '\0';
1605			lreply(230, "%s", line);
1606		}
1607		(void) fflush(stdout);
1608		(void) fclose(fd);
1609	}
1610	if (guest) {
1611		if (ident != NULL)
1612			free(ident);
1613		ident = strdup(passwd);
1614		if (ident == NULL)
1615			fatalerror("Ran out of memory.");
1616
1617		reply(230, "Guest login ok, access restrictions apply.");
1618#ifdef SETPROCTITLE
1619#ifdef VIRTUAL_HOSTING
1620		if (thishost != firsthost)
1621			snprintf(proctitle, sizeof(proctitle),
1622				 "%s: anonymous(%s)/%s", remotehost, hostname,
1623				 passwd);
1624		else
1625#endif
1626			snprintf(proctitle, sizeof(proctitle),
1627				 "%s: anonymous/%s", remotehost, passwd);
1628		setproctitle("%s", proctitle);
1629#endif /* SETPROCTITLE */
1630		if (logging)
1631			syslog(LOG_INFO, "ANONYMOUS FTP LOGIN FROM %s, %s",
1632			    remotehost, passwd);
1633	} else {
1634		if (dochroot)
1635			reply(230, "User %s logged in, "
1636				   "access restrictions apply.", pw->pw_name);
1637		else
1638			reply(230, "User %s logged in.", pw->pw_name);
1639
1640#ifdef SETPROCTITLE
1641		snprintf(proctitle, sizeof(proctitle),
1642			 "%s: user/%s", remotehost, pw->pw_name);
1643		setproctitle("%s", proctitle);
1644#endif /* SETPROCTITLE */
1645		if (logging)
1646			syslog(LOG_INFO, "FTP LOGIN FROM %s as %s",
1647			    remotehost, pw->pw_name);
1648	}
1649	if (logging && (guest || dochroot))
1650		syslog(LOG_INFO, "session root changed to %s", chrootdir);
1651#ifdef	LOGIN_CAP
1652	login_close(lc);
1653#endif
1654	if (residue)
1655		free(residue);
1656	return;
1657bad:
1658	/* Forget all about it... */
1659#ifdef	LOGIN_CAP
1660	login_close(lc);
1661#endif
1662	if (residue)
1663		free(residue);
1664	end_login();
1665}
1666
1667void
1668retrieve(char *cmd, char *name)
1669{
1670	FILE *fin, *dout;
1671	struct stat st;
1672	int (*closefunc)(FILE *);
1673	time_t start;
1674
1675	if (cmd == 0) {
1676		fin = fopen(name, "r"), closefunc = fclose;
1677		st.st_size = 0;
1678	} else {
1679		char line[BUFSIZ];
1680
1681		(void) snprintf(line, sizeof(line), cmd, name), name = line;
1682		fin = ftpd_popen(line, "r"), closefunc = ftpd_pclose;
1683		st.st_size = -1;
1684		st.st_blksize = BUFSIZ;
1685	}
1686	if (fin == NULL) {
1687		if (errno != 0) {
1688			perror_reply(550, name);
1689			if (cmd == 0) {
1690				LOGCMD("get", name);
1691			}
1692		}
1693		return;
1694	}
1695	byte_count = -1;
1696	if (cmd == 0) {
1697		if (fstat(fileno(fin), &st) < 0) {
1698			perror_reply(550, name);
1699			goto done;
1700		}
1701		if (!S_ISREG(st.st_mode)) {
1702			/*
1703			 * Never sending a raw directory is a workaround
1704			 * for buggy clients that will attempt to RETR
1705			 * a directory before listing it, e.g., Mozilla.
1706			 * Preventing a guest from getting irregular files
1707			 * is a simple security measure.
1708			 */
1709			if (S_ISDIR(st.st_mode) || guest) {
1710				reply(550, "%s: not a plain file.", name);
1711				goto done;
1712			}
1713			st.st_size = -1;
1714			/* st.st_blksize is set for all descriptor types */
1715		}
1716	}
1717	if (restart_point) {
1718		if (type == TYPE_A) {
1719			off_t i, n;
1720			int c;
1721
1722			n = restart_point;
1723			i = 0;
1724			while (i++ < n) {
1725				if ((c=getc(fin)) == EOF) {
1726					perror_reply(550, name);
1727					goto done;
1728				}
1729				if (c == '\n')
1730					i++;
1731			}
1732		} else if (lseek(fileno(fin), restart_point, L_SET) < 0) {
1733			perror_reply(550, name);
1734			goto done;
1735		}
1736	}
1737	dout = dataconn(name, st.st_size, "w");
1738	if (dout == NULL)
1739		goto done;
1740	time(&start);
1741	send_data(fin, dout, st.st_blksize, st.st_size,
1742		  restart_point == 0 && cmd == 0 && S_ISREG(st.st_mode));
1743	if (cmd == 0 && guest && stats && byte_count > 0)
1744		logxfer(name, byte_count, start);
1745	(void) fclose(dout);
1746	data = -1;
1747	pdata = -1;
1748done:
1749	if (cmd == 0)
1750		LOGBYTES("get", name, byte_count);
1751	(*closefunc)(fin);
1752}
1753
1754void
1755store(char *name, char *mode, int unique)
1756{
1757	int fd;
1758	FILE *fout, *din;
1759	int (*closefunc)(FILE *);
1760
1761	if (*mode == 'a') {		/* APPE */
1762		if (unique) {
1763			/* Programming error */
1764			syslog(LOG_ERR, "Internal: unique flag to APPE");
1765			unique = 0;
1766		}
1767		if (guest && noguestmod) {
1768			reply(550, "Appending to existing file denied.");
1769			goto err;
1770		}
1771		restart_point = 0;	/* not affected by preceding REST */
1772	}
1773	if (unique)			/* STOU overrides REST */
1774		restart_point = 0;
1775	if (guest && noguestmod) {
1776		if (restart_point) {	/* guest STOR w/REST */
1777			reply(550, "Modifying existing file denied.");
1778			goto err;
1779		} else			/* treat guest STOR as STOU */
1780			unique = 1;
1781	}
1782
1783	if (restart_point)
1784		mode = "r+";	/* so ASCII manual seek can work */
1785	if (unique) {
1786		if ((fd = guniquefd(name, &name)) < 0)
1787			goto err;
1788		fout = fdopen(fd, mode);
1789	} else
1790		fout = fopen(name, mode);
1791	closefunc = fclose;
1792	if (fout == NULL) {
1793		perror_reply(553, name);
1794		goto err;
1795	}
1796	byte_count = -1;
1797	if (restart_point) {
1798		if (type == TYPE_A) {
1799			off_t i, n;
1800			int c;
1801
1802			n = restart_point;
1803			i = 0;
1804			while (i++ < n) {
1805				if ((c=getc(fout)) == EOF) {
1806					perror_reply(550, name);
1807					goto done;
1808				}
1809				if (c == '\n')
1810					i++;
1811			}
1812			/*
1813			 * We must do this seek to "current" position
1814			 * because we are changing from reading to
1815			 * writing.
1816			 */
1817			if (fseeko(fout, 0, SEEK_CUR) < 0) {
1818				perror_reply(550, name);
1819				goto done;
1820			}
1821		} else if (lseek(fileno(fout), restart_point, L_SET) < 0) {
1822			perror_reply(550, name);
1823			goto done;
1824		}
1825	}
1826	din = dataconn(name, -1, "r");
1827	if (din == NULL)
1828		goto done;
1829	if (receive_data(din, fout) == 0) {
1830		if (unique)
1831			reply(226, "Transfer complete (unique file name:%s).",
1832			    name);
1833		else
1834			reply(226, "Transfer complete.");
1835	}
1836	(void) fclose(din);
1837	data = -1;
1838	pdata = -1;
1839done:
1840	LOGBYTES(*mode == 'a' ? "append" : "put", name, byte_count);
1841	(*closefunc)(fout);
1842	return;
1843err:
1844	LOGCMD(*mode == 'a' ? "append" : "put" , name);
1845	return;
1846}
1847
1848static FILE *
1849getdatasock(char *mode)
1850{
1851	int on = 1, s, t, tries;
1852
1853	if (data >= 0)
1854		return (fdopen(data, mode));
1855
1856	s = socket(data_dest.su_family, SOCK_STREAM, 0);
1857	if (s < 0)
1858		goto bad;
1859	if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
1860		syslog(LOG_WARNING, "data setsockopt (SO_REUSEADDR): %m");
1861	/* anchor socket to avoid multi-homing problems */
1862	data_source = ctrl_addr;
1863	data_source.su_port = htons(dataport);
1864	(void) seteuid(0);
1865	for (tries = 1; ; tries++) {
1866		/*
1867		 * We should loop here since it's possible that
1868		 * another ftpd instance has passed this point and is
1869		 * trying to open a data connection in active mode now.
1870		 * Until the other connection is opened, we'll be getting
1871		 * EADDRINUSE because no SOCK_STREAM sockets in the system
1872		 * can share both local and remote addresses, localIP:20
1873		 * and *:* in this case.
1874		 */
1875		if (bind(s, (struct sockaddr *)&data_source,
1876		    data_source.su_len) >= 0)
1877			break;
1878		if (errno != EADDRINUSE || tries > 10)
1879			goto bad;
1880		sleep(tries);
1881	}
1882	(void) seteuid(pw->pw_uid);
1883#ifdef IP_TOS
1884	if (data_source.su_family == AF_INET)
1885      {
1886	on = IPTOS_THROUGHPUT;
1887	if (setsockopt(s, IPPROTO_IP, IP_TOS, &on, sizeof(int)) < 0)
1888		syslog(LOG_WARNING, "data setsockopt (IP_TOS): %m");
1889      }
1890#endif
1891#ifdef TCP_NOPUSH
1892	/*
1893	 * Turn off push flag to keep sender TCP from sending short packets
1894	 * at the boundaries of each write().
1895	 */
1896	on = 1;
1897	if (setsockopt(s, IPPROTO_TCP, TCP_NOPUSH, &on, sizeof on) < 0)
1898		syslog(LOG_WARNING, "data setsockopt (TCP_NOPUSH): %m");
1899#endif
1900	return (fdopen(s, mode));
1901bad:
1902	/* Return the real value of errno (close may change it) */
1903	t = errno;
1904	(void) seteuid(pw->pw_uid);
1905	(void) close(s);
1906	errno = t;
1907	return (NULL);
1908}
1909
1910static FILE *
1911dataconn(char *name, off_t size, char *mode)
1912{
1913	char sizebuf[32];
1914	FILE *file;
1915	int retry = 0, tos, conerrno;
1916
1917	file_size = size;
1918	byte_count = 0;
1919	if (size != -1)
1920		(void) snprintf(sizebuf, sizeof(sizebuf),
1921				" (%jd bytes)", (intmax_t)size);
1922	else
1923		*sizebuf = '\0';
1924	if (pdata >= 0) {
1925		union sockunion from;
1926		socklen_t fromlen = ctrl_addr.su_len;
1927		int flags, s;
1928		struct timeval timeout;
1929		fd_set set;
1930
1931		FD_ZERO(&set);
1932		FD_SET(pdata, &set);
1933
1934		timeout.tv_usec = 0;
1935		timeout.tv_sec = 120;
1936
1937		/*
1938		 * Granted a socket is in the blocking I/O mode,
1939		 * accept() will block after a successful select()
1940		 * if the selected connection dies in between.
1941		 * Therefore set the non-blocking I/O flag here.
1942		 */
1943		if ((flags = fcntl(pdata, F_GETFL, 0)) == -1 ||
1944		    fcntl(pdata, F_SETFL, flags | O_NONBLOCK) == -1)
1945			goto pdata_err;
1946		if (select(pdata+1, &set, NULL, NULL, &timeout) <= 0 ||
1947		    (s = accept(pdata, (struct sockaddr *) &from, &fromlen)) < 0)
1948			goto pdata_err;
1949		(void) close(pdata);
1950		pdata = s;
1951		/*
1952		 * Unset the inherited non-blocking I/O flag
1953		 * on the child socket so stdio can work on it.
1954		 */
1955		if ((flags = fcntl(pdata, F_GETFL, 0)) == -1 ||
1956		    fcntl(pdata, F_SETFL, flags & ~O_NONBLOCK) == -1)
1957			goto pdata_err;
1958#ifdef IP_TOS
1959		if (from.su_family == AF_INET)
1960	      {
1961		tos = IPTOS_THROUGHPUT;
1962		if (setsockopt(s, IPPROTO_IP, IP_TOS, &tos, sizeof(int)) < 0)
1963			syslog(LOG_WARNING, "pdata setsockopt (IP_TOS): %m");
1964	      }
1965#endif
1966		reply(150, "Opening %s mode data connection for '%s'%s.",
1967		     type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
1968		return (fdopen(pdata, mode));
1969pdata_err:
1970		reply(425, "Can't open data connection.");
1971		(void) close(pdata);
1972		pdata = -1;
1973		return (NULL);
1974	}
1975	if (data >= 0) {
1976		reply(125, "Using existing data connection for '%s'%s.",
1977		    name, sizebuf);
1978		usedefault = 1;
1979		return (fdopen(data, mode));
1980	}
1981	if (usedefault)
1982		data_dest = his_addr;
1983	usedefault = 1;
1984	do {
1985		file = getdatasock(mode);
1986		if (file == NULL) {
1987			char hostbuf[NI_MAXHOST], portbuf[NI_MAXSERV];
1988
1989			if (getnameinfo((struct sockaddr *)&data_source,
1990				data_source.su_len,
1991				hostbuf, sizeof(hostbuf) - 1,
1992				portbuf, sizeof(portbuf) - 1,
1993				NI_NUMERICHOST|NI_NUMERICSERV))
1994					*hostbuf = *portbuf = 0;
1995			hostbuf[sizeof(hostbuf) - 1] = 0;
1996			portbuf[sizeof(portbuf) - 1] = 0;
1997			reply(425, "Can't create data socket (%s,%s): %s.",
1998				hostbuf, portbuf, strerror(errno));
1999			return (NULL);
2000		}
2001		data = fileno(file);
2002		conerrno = 0;
2003		if (connect(data, (struct sockaddr *)&data_dest,
2004		    data_dest.su_len) == 0)
2005			break;
2006		conerrno = errno;
2007		(void) fclose(file);
2008		data = -1;
2009		if (conerrno == EADDRINUSE) {
2010			sleep(swaitint);
2011			retry += swaitint;
2012		} else {
2013			break;
2014		}
2015	} while (retry <= swaitmax);
2016	if (conerrno != 0) {
2017		reply(425, "Can't build data connection: %s.",
2018			   strerror(conerrno));
2019		return (NULL);
2020	}
2021	reply(150, "Opening %s mode data connection for '%s'%s.",
2022	     type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
2023	return (file);
2024}
2025
2026/*
2027 * A helper macro to avoid code duplication
2028 * in send_data() and receive_data().
2029 *
2030 * XXX We have to block SIGURG during putc() because BSD stdio
2031 * is unable to restart interrupted write operations and hence
2032 * the entire buffer contents will be lost as soon as a write()
2033 * call indicates EINTR to stdio.
2034 */
2035#define FTPD_PUTC(ch, file, label)					\
2036	do {								\
2037		int ret;						\
2038									\
2039		do {							\
2040			START_UNSAFE;					\
2041			ret = putc((ch), (file));			\
2042			END_UNSAFE;					\
2043			CHECKOOB(return (-1))				\
2044			else if (ferror(file))				\
2045				goto label;				\
2046			clearerr(file);					\
2047		} while (ret == EOF);					\
2048	} while (0)
2049
2050/*
2051 * Tranfer the contents of "instr" to "outstr" peer using the appropriate
2052 * encapsulation of the data subject to Mode, Structure, and Type.
2053 *
2054 * NB: Form isn't handled.
2055 */
2056static int
2057send_data(FILE *instr, FILE *outstr, size_t blksize, off_t filesize, int isreg)
2058{
2059	int c, cp, filefd, netfd;
2060	char *buf;
2061
2062	STARTXFER;
2063
2064	switch (type) {
2065
2066	case TYPE_A:
2067		cp = EOF;
2068		for (;;) {
2069			c = getc(instr);
2070			CHECKOOB(return (-1))
2071			else if (c == EOF && ferror(instr))
2072				goto file_err;
2073			if (c == EOF) {
2074				if (ferror(instr)) {	/* resume after OOB */
2075					clearerr(instr);
2076					continue;
2077				}
2078				if (feof(instr))	/* EOF */
2079					break;
2080				syslog(LOG_ERR, "Internal: impossible condition"
2081						" on file after getc()");
2082				goto file_err;
2083			}
2084			if (c == '\n' && cp != '\r') {
2085				FTPD_PUTC('\r', outstr, data_err);
2086				byte_count++;
2087			}
2088			FTPD_PUTC(c, outstr, data_err);
2089			byte_count++;
2090			cp = c;
2091		}
2092#ifdef notyet	/* BSD stdio isn't ready for that */
2093		while (fflush(outstr) == EOF) {
2094			CHECKOOB(return (-1))
2095			else
2096				goto data_err;
2097			clearerr(outstr);
2098		}
2099		ENDXFER;
2100#else
2101		ENDXFER;
2102		if (fflush(outstr) == EOF)
2103			goto data_err;
2104#endif
2105		reply(226, "Transfer complete.");
2106		return (0);
2107
2108	case TYPE_I:
2109	case TYPE_L:
2110		/*
2111		 * isreg is only set if we are not doing restart and we
2112		 * are sending a regular file
2113		 */
2114		netfd = fileno(outstr);
2115		filefd = fileno(instr);
2116
2117		if (isreg) {
2118			char *msg = "Transfer complete.";
2119			off_t cnt, offset;
2120			int err;
2121
2122			cnt = offset = 0;
2123
2124			while (filesize > 0) {
2125				err = sendfile(filefd, netfd, offset, 0,
2126					       NULL, &cnt, 0);
2127				/*
2128				 * Calculate byte_count before OOB processing.
2129				 * It can be used in myoob() later.
2130				 */
2131				byte_count += cnt;
2132				offset += cnt;
2133				filesize -= cnt;
2134				CHECKOOB(return (-1))
2135				else if (err == -1) {
2136					if (errno != EINTR &&
2137					    cnt == 0 && offset == 0)
2138						goto oldway;
2139					goto data_err;
2140				}
2141				if (err == -1)	/* resume after OOB */
2142					continue;
2143				/*
2144				 * We hit the EOF prematurely.
2145				 * Perhaps the file was externally truncated.
2146				 */
2147				if (cnt == 0) {
2148					msg = "Transfer finished due to "
2149					      "premature end of file.";
2150					break;
2151				}
2152			}
2153			ENDXFER;
2154			reply(226, "%s", msg);
2155			return (0);
2156		}
2157
2158oldway:
2159		if ((buf = malloc(blksize)) == NULL) {
2160			ENDXFER;
2161			reply(451, "Ran out of memory.");
2162			return (-1);
2163		}
2164
2165		for (;;) {
2166			int cnt, len;
2167			char *bp;
2168
2169			cnt = read(filefd, buf, blksize);
2170			CHECKOOB(free(buf); return (-1))
2171			else if (cnt < 0) {
2172				free(buf);
2173				goto file_err;
2174			}
2175			if (cnt < 0)	/* resume after OOB */
2176				continue;
2177			if (cnt == 0)	/* EOF */
2178				break;
2179			for (len = cnt, bp = buf; len > 0;) {
2180				cnt = write(netfd, bp, len);
2181				CHECKOOB(free(buf); return (-1))
2182				else if (cnt < 0) {
2183					free(buf);
2184					goto data_err;
2185				}
2186				if (cnt <= 0)
2187					continue;
2188				len -= cnt;
2189				bp += cnt;
2190				byte_count += cnt;
2191			}
2192		}
2193		ENDXFER;
2194		free(buf);
2195		reply(226, "Transfer complete.");
2196		return (0);
2197	default:
2198		ENDXFER;
2199		reply(550, "Unimplemented TYPE %d in send_data.", type);
2200		return (-1);
2201	}
2202
2203data_err:
2204	ENDXFER;
2205	perror_reply(426, "Data connection");
2206	return (-1);
2207
2208file_err:
2209	ENDXFER;
2210	perror_reply(551, "Error on input file");
2211	return (-1);
2212}
2213
2214/*
2215 * Transfer data from peer to "outstr" using the appropriate encapulation of
2216 * the data subject to Mode, Structure, and Type.
2217 *
2218 * N.B.: Form isn't handled.
2219 */
2220static int
2221receive_data(FILE *instr, FILE *outstr)
2222{
2223	int c, cp;
2224	int bare_lfs = 0;
2225
2226	STARTXFER;
2227
2228	switch (type) {
2229
2230	case TYPE_I:
2231	case TYPE_L:
2232		for (;;) {
2233			int cnt, len;
2234			char *bp;
2235			char buf[BUFSIZ];
2236
2237			cnt = read(fileno(instr), buf, sizeof(buf));
2238			CHECKOOB(return (-1))
2239			else if (cnt < 0)
2240				goto data_err;
2241			if (cnt < 0)	/* resume after OOB */
2242				continue;
2243			if (cnt == 0)	/* EOF */
2244				break;
2245			for (len = cnt, bp = buf; len > 0;) {
2246				cnt = write(fileno(outstr), bp, len);
2247				CHECKOOB(return (-1))
2248				else if (cnt < 0)
2249					goto file_err;
2250				if (cnt <= 0)
2251					continue;
2252				len -= cnt;
2253				bp += cnt;
2254				byte_count += cnt;
2255			}
2256		}
2257		ENDXFER;
2258		return (0);
2259
2260	case TYPE_E:
2261		ENDXFER;
2262		reply(553, "TYPE E not implemented.");
2263		return (-1);
2264
2265	case TYPE_A:
2266		cp = EOF;
2267		for (;;) {
2268			c = getc(instr);
2269			CHECKOOB(return (-1))
2270			else if (c == EOF && ferror(instr))
2271				goto data_err;
2272			if (c == EOF && ferror(instr)) { /* resume after OOB */
2273				clearerr(instr);
2274				continue;
2275			}
2276
2277			if (cp == '\r') {
2278				if (c != '\n')
2279					FTPD_PUTC('\r', outstr, file_err);
2280			} else
2281				if (c == '\n')
2282					bare_lfs++;
2283			if (c == '\r') {
2284				byte_count++;
2285				cp = c;
2286				continue;
2287			}
2288
2289			/* Check for EOF here in order not to lose last \r. */
2290			if (c == EOF) {
2291				if (feof(instr))	/* EOF */
2292					break;
2293				syslog(LOG_ERR, "Internal: impossible condition"
2294						" on data stream after getc()");
2295				goto data_err;
2296			}
2297
2298			byte_count++;
2299			FTPD_PUTC(c, outstr, file_err);
2300			cp = c;
2301		}
2302#ifdef notyet	/* BSD stdio isn't ready for that */
2303		while (fflush(outstr) == EOF) {
2304			CHECKOOB(return (-1))
2305			else
2306				goto file_err;
2307			clearerr(outstr);
2308		}
2309		ENDXFER;
2310#else
2311		ENDXFER;
2312		if (fflush(outstr) == EOF)
2313			goto file_err;
2314#endif
2315		if (bare_lfs) {
2316			lreply(226,
2317		"WARNING! %d bare linefeeds received in ASCII mode.",
2318			    bare_lfs);
2319		(void)printf("   File may not have transferred correctly.\r\n");
2320		}
2321		return (0);
2322	default:
2323		ENDXFER;
2324		reply(550, "Unimplemented TYPE %d in receive_data.", type);
2325		return (-1);
2326	}
2327
2328data_err:
2329	ENDXFER;
2330	perror_reply(426, "Data connection");
2331	return (-1);
2332
2333file_err:
2334	ENDXFER;
2335	perror_reply(452, "Error writing to file");
2336	return (-1);
2337}
2338
2339void
2340statfilecmd(char *filename)
2341{
2342	FILE *fin;
2343	int atstart;
2344	int c, code;
2345	char line[LINE_MAX];
2346	struct stat st;
2347
2348	code = lstat(filename, &st) == 0 && S_ISDIR(st.st_mode) ? 212 : 213;
2349	(void)snprintf(line, sizeof(line), _PATH_LS " -lgA %s", filename);
2350	fin = ftpd_popen(line, "r");
2351	if (fin == NULL) {
2352		perror_reply(551, filename);
2353		return;
2354	}
2355	lreply(code, "Status of %s:", filename);
2356	atstart = 1;
2357	while ((c = getc(fin)) != EOF) {
2358		if (c == '\n') {
2359			if (ferror(stdout)){
2360				perror_reply(421, "Control connection");
2361				(void) ftpd_pclose(fin);
2362				dologout(1);
2363				/* NOTREACHED */
2364			}
2365			if (ferror(fin)) {
2366				perror_reply(551, filename);
2367				(void) ftpd_pclose(fin);
2368				return;
2369			}
2370			(void) putc('\r', stdout);
2371		}
2372		/*
2373		 * RFC 959 says neutral text should be prepended before
2374		 * a leading 3-digit number followed by whitespace, but
2375		 * many ftp clients can be confused by any leading digits,
2376		 * as a matter of fact.
2377		 */
2378		if (atstart && isdigit(c))
2379			(void) putc(' ', stdout);
2380		(void) putc(c, stdout);
2381		atstart = (c == '\n');
2382	}
2383	(void) ftpd_pclose(fin);
2384	reply(code, "End of status.");
2385}
2386
2387void
2388statcmd(void)
2389{
2390	union sockunion *su;
2391	u_char *a, *p;
2392	char hname[NI_MAXHOST];
2393	int ispassive;
2394
2395	if (hostinfo) {
2396		lreply(211, "%s FTP server status:", hostname);
2397		printf("     %s\r\n", version);
2398	} else
2399		lreply(211, "FTP server status:");
2400	printf("     Connected to %s", remotehost);
2401	if (!getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
2402			 hname, sizeof(hname) - 1, NULL, 0, NI_NUMERICHOST)) {
2403		hname[sizeof(hname) - 1] = 0;
2404		if (strcmp(hname, remotehost) != 0)
2405			printf(" (%s)", hname);
2406	}
2407	printf("\r\n");
2408	if (logged_in) {
2409		if (guest)
2410			printf("     Logged in anonymously\r\n");
2411		else
2412			printf("     Logged in as %s\r\n", pw->pw_name);
2413	} else if (askpasswd)
2414		printf("     Waiting for password\r\n");
2415	else
2416		printf("     Waiting for user name\r\n");
2417	printf("     TYPE: %s", typenames[type]);
2418	if (type == TYPE_A || type == TYPE_E)
2419		printf(", FORM: %s", formnames[form]);
2420	if (type == TYPE_L)
2421#if CHAR_BIT == 8
2422		printf(" %d", CHAR_BIT);
2423#else
2424		printf(" %d", bytesize);	/* need definition! */
2425#endif
2426	printf("; STRUcture: %s; transfer MODE: %s\r\n",
2427	    strunames[stru], modenames[mode]);
2428	if (data != -1)
2429		printf("     Data connection open\r\n");
2430	else if (pdata != -1) {
2431		ispassive = 1;
2432		su = &pasv_addr;
2433		goto printaddr;
2434	} else if (usedefault == 0) {
2435		ispassive = 0;
2436		su = &data_dest;
2437printaddr:
2438#define UC(b) (((int) b) & 0xff)
2439		if (epsvall) {
2440			printf("     EPSV only mode (EPSV ALL)\r\n");
2441			goto epsvonly;
2442		}
2443
2444		/* PORT/PASV */
2445		if (su->su_family == AF_INET) {
2446			a = (u_char *) &su->su_sin.sin_addr;
2447			p = (u_char *) &su->su_sin.sin_port;
2448			printf("     %s (%d,%d,%d,%d,%d,%d)\r\n",
2449				ispassive ? "PASV" : "PORT",
2450				UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
2451				UC(p[0]), UC(p[1]));
2452		}
2453
2454		/* LPRT/LPSV */
2455	    {
2456		int alen, af, i;
2457
2458		switch (su->su_family) {
2459		case AF_INET:
2460			a = (u_char *) &su->su_sin.sin_addr;
2461			p = (u_char *) &su->su_sin.sin_port;
2462			alen = sizeof(su->su_sin.sin_addr);
2463			af = 4;
2464			break;
2465		case AF_INET6:
2466			a = (u_char *) &su->su_sin6.sin6_addr;
2467			p = (u_char *) &su->su_sin6.sin6_port;
2468			alen = sizeof(su->su_sin6.sin6_addr);
2469			af = 6;
2470			break;
2471		default:
2472			af = 0;
2473			break;
2474		}
2475		if (af) {
2476			printf("     %s (%d,%d,", ispassive ? "LPSV" : "LPRT",
2477				af, alen);
2478			for (i = 0; i < alen; i++)
2479				printf("%d,", UC(a[i]));
2480			printf("%d,%d,%d)\r\n", 2, UC(p[0]), UC(p[1]));
2481		}
2482	    }
2483
2484epsvonly:;
2485		/* EPRT/EPSV */
2486	    {
2487		int af;
2488
2489		switch (su->su_family) {
2490		case AF_INET:
2491			af = 1;
2492			break;
2493		case AF_INET6:
2494			af = 2;
2495			break;
2496		default:
2497			af = 0;
2498			break;
2499		}
2500		if (af) {
2501			union sockunion tmp;
2502
2503			tmp = *su;
2504			if (tmp.su_family == AF_INET6)
2505				tmp.su_sin6.sin6_scope_id = 0;
2506			if (!getnameinfo((struct sockaddr *)&tmp, tmp.su_len,
2507					hname, sizeof(hname) - 1, NULL, 0,
2508					NI_NUMERICHOST)) {
2509				hname[sizeof(hname) - 1] = 0;
2510				printf("     %s |%d|%s|%d|\r\n",
2511					ispassive ? "EPSV" : "EPRT",
2512					af, hname, htons(tmp.su_port));
2513			}
2514		}
2515	    }
2516#undef UC
2517	} else
2518		printf("     No data connection\r\n");
2519	reply(211, "End of status.");
2520}
2521
2522void
2523fatalerror(char *s)
2524{
2525
2526	reply(451, "Error in server: %s", s);
2527	reply(221, "Closing connection due to server error.");
2528	dologout(0);
2529	/* NOTREACHED */
2530}
2531
2532void
2533reply(int n, const char *fmt, ...)
2534{
2535	va_list ap;
2536
2537	(void)printf("%d ", n);
2538	va_start(ap, fmt);
2539	(void)vprintf(fmt, ap);
2540	va_end(ap);
2541	(void)printf("\r\n");
2542	(void)fflush(stdout);
2543	if (ftpdebug) {
2544		syslog(LOG_DEBUG, "<--- %d ", n);
2545		va_start(ap, fmt);
2546		vsyslog(LOG_DEBUG, fmt, ap);
2547		va_end(ap);
2548	}
2549}
2550
2551void
2552lreply(int n, const char *fmt, ...)
2553{
2554	va_list ap;
2555
2556	(void)printf("%d- ", n);
2557	va_start(ap, fmt);
2558	(void)vprintf(fmt, ap);
2559	va_end(ap);
2560	(void)printf("\r\n");
2561	(void)fflush(stdout);
2562	if (ftpdebug) {
2563		syslog(LOG_DEBUG, "<--- %d- ", n);
2564		va_start(ap, fmt);
2565		vsyslog(LOG_DEBUG, fmt, ap);
2566		va_end(ap);
2567	}
2568}
2569
2570static void
2571ack(char *s)
2572{
2573
2574	reply(250, "%s command successful.", s);
2575}
2576
2577void
2578nack(char *s)
2579{
2580
2581	reply(502, "%s command not implemented.", s);
2582}
2583
2584/* ARGSUSED */
2585void
2586yyerror(char *s)
2587{
2588	char *cp;
2589
2590	if ((cp = strchr(cbuf,'\n')))
2591		*cp = '\0';
2592	reply(500, "%s: command not understood.", cbuf);
2593}
2594
2595void
2596delete(char *name)
2597{
2598	struct stat st;
2599
2600	LOGCMD("delete", name);
2601	if (lstat(name, &st) < 0) {
2602		perror_reply(550, name);
2603		return;
2604	}
2605	if (S_ISDIR(st.st_mode)) {
2606		if (rmdir(name) < 0) {
2607			perror_reply(550, name);
2608			return;
2609		}
2610		goto done;
2611	}
2612	if (guest && noguestmod) {
2613		reply(550, "Operation not permitted.");
2614		return;
2615	}
2616	if (unlink(name) < 0) {
2617		perror_reply(550, name);
2618		return;
2619	}
2620done:
2621	ack("DELE");
2622}
2623
2624void
2625cwd(char *path)
2626{
2627
2628	if (chdir(path) < 0)
2629		perror_reply(550, path);
2630	else
2631		ack("CWD");
2632}
2633
2634void
2635makedir(char *name)
2636{
2637	char *s;
2638
2639	LOGCMD("mkdir", name);
2640	if (guest && noguestmkd)
2641		reply(550, "Operation not permitted.");
2642	else if (mkdir(name, 0777) < 0)
2643		perror_reply(550, name);
2644	else {
2645		if ((s = doublequote(name)) == NULL)
2646			fatalerror("Ran out of memory.");
2647		reply(257, "\"%s\" directory created.", s);
2648		free(s);
2649	}
2650}
2651
2652void
2653removedir(char *name)
2654{
2655
2656	LOGCMD("rmdir", name);
2657	if (rmdir(name) < 0)
2658		perror_reply(550, name);
2659	else
2660		ack("RMD");
2661}
2662
2663void
2664pwd(void)
2665{
2666	char *s, path[MAXPATHLEN + 1];
2667
2668	if (getcwd(path, sizeof(path)) == NULL)
2669		perror_reply(550, "Get current directory");
2670	else {
2671		if ((s = doublequote(path)) == NULL)
2672			fatalerror("Ran out of memory.");
2673		reply(257, "\"%s\" is current directory.", s);
2674		free(s);
2675	}
2676}
2677
2678char *
2679renamefrom(char *name)
2680{
2681	struct stat st;
2682
2683	if (guest && noguestmod) {
2684		reply(550, "Operation not permitted.");
2685		return (NULL);
2686	}
2687	if (lstat(name, &st) < 0) {
2688		perror_reply(550, name);
2689		return (NULL);
2690	}
2691	reply(350, "File exists, ready for destination name.");
2692	return (name);
2693}
2694
2695void
2696renamecmd(char *from, char *to)
2697{
2698	struct stat st;
2699
2700	LOGCMD2("rename", from, to);
2701
2702	if (guest && (stat(to, &st) == 0)) {
2703		reply(550, "%s: permission denied.", to);
2704		return;
2705	}
2706
2707	if (rename(from, to) < 0)
2708		perror_reply(550, "rename");
2709	else
2710		ack("RNTO");
2711}
2712
2713static void
2714dolog(struct sockaddr *who)
2715{
2716	char who_name[NI_MAXHOST];
2717
2718	realhostname_sa(remotehost, sizeof(remotehost) - 1, who, who->sa_len);
2719	remotehost[sizeof(remotehost) - 1] = 0;
2720	if (getnameinfo(who, who->sa_len,
2721		who_name, sizeof(who_name) - 1, NULL, 0, NI_NUMERICHOST))
2722			*who_name = 0;
2723	who_name[sizeof(who_name) - 1] = 0;
2724
2725#ifdef SETPROCTITLE
2726#ifdef VIRTUAL_HOSTING
2727	if (thishost != firsthost)
2728		snprintf(proctitle, sizeof(proctitle), "%s: connected (to %s)",
2729			 remotehost, hostname);
2730	else
2731#endif
2732		snprintf(proctitle, sizeof(proctitle), "%s: connected",
2733			 remotehost);
2734	setproctitle("%s", proctitle);
2735#endif /* SETPROCTITLE */
2736
2737	if (logging) {
2738#ifdef VIRTUAL_HOSTING
2739		if (thishost != firsthost)
2740			syslog(LOG_INFO, "connection from %s (%s) to %s",
2741			       remotehost, who_name, hostname);
2742		else
2743#endif
2744			syslog(LOG_INFO, "connection from %s (%s)",
2745			       remotehost, who_name);
2746	}
2747}
2748
2749/*
2750 * Record logout in wtmp file
2751 * and exit with supplied status.
2752 */
2753void
2754dologout(int status)
2755{
2756
2757	if (logged_in && dowtmp) {
2758		(void) seteuid(0);
2759		ftpd_logwtmp(wtmpid, NULL, NULL);
2760	}
2761	/* beware of flushing buffers after a SIGPIPE */
2762	_exit(status);
2763}
2764
2765static void
2766sigurg(int signo)
2767{
2768
2769	recvurg = 1;
2770}
2771
2772static void
2773maskurg(int flag)
2774{
2775	int oerrno;
2776	sigset_t sset;
2777
2778	if (!transflag) {
2779		syslog(LOG_ERR, "Internal: maskurg() while no transfer");
2780		return;
2781	}
2782	oerrno = errno;
2783	sigemptyset(&sset);
2784	sigaddset(&sset, SIGURG);
2785	sigprocmask(flag ? SIG_BLOCK : SIG_UNBLOCK, &sset, NULL);
2786	errno = oerrno;
2787}
2788
2789static void
2790flagxfer(int flag)
2791{
2792
2793	if (flag) {
2794		if (transflag)
2795			syslog(LOG_ERR, "Internal: flagxfer(1): "
2796					"transfer already under way");
2797		transflag = 1;
2798		maskurg(0);
2799		recvurg = 0;
2800	} else {
2801		if (!transflag)
2802			syslog(LOG_ERR, "Internal: flagxfer(0): "
2803					"no active transfer");
2804		maskurg(1);
2805		transflag = 0;
2806	}
2807}
2808
2809/*
2810 * Returns 0 if OK to resume or -1 if abort requested.
2811 */
2812static int
2813myoob(void)
2814{
2815	char *cp;
2816	int ret;
2817
2818	if (!transflag) {
2819		syslog(LOG_ERR, "Internal: myoob() while no transfer");
2820		return (0);
2821	}
2822	cp = tmpline;
2823	ret = getline(cp, 7, stdin);
2824	if (ret == -1) {
2825		reply(221, "You could at least say goodbye.");
2826		dologout(0);
2827	} else if (ret == -2) {
2828		/* Ignore truncated command. */
2829		return (0);
2830	}
2831	upper(cp);
2832	if (strcmp(cp, "ABOR\r\n") == 0) {
2833		tmpline[0] = '\0';
2834		reply(426, "Transfer aborted. Data connection closed.");
2835		reply(226, "Abort successful.");
2836		return (-1);
2837	}
2838	if (strcmp(cp, "STAT\r\n") == 0) {
2839		tmpline[0] = '\0';
2840		if (file_size != -1)
2841			reply(213, "Status: %jd of %jd bytes transferred.",
2842				   (intmax_t)byte_count, (intmax_t)file_size);
2843		else
2844			reply(213, "Status: %jd bytes transferred.",
2845				   (intmax_t)byte_count);
2846	}
2847	return (0);
2848}
2849
2850/*
2851 * Note: a response of 425 is not mentioned as a possible response to
2852 *	the PASV command in RFC959. However, it has been blessed as
2853 *	a legitimate response by Jon Postel in a telephone conversation
2854 *	with Rick Adams on 25 Jan 89.
2855 */
2856void
2857passive(void)
2858{
2859	socklen_t len;
2860	int on;
2861	char *p, *a;
2862
2863	if (pdata >= 0)		/* close old port if one set */
2864		close(pdata);
2865
2866	pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
2867	if (pdata < 0) {
2868		perror_reply(425, "Can't open passive connection");
2869		return;
2870	}
2871	on = 1;
2872	if (setsockopt(pdata, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
2873		syslog(LOG_WARNING, "pdata setsockopt (SO_REUSEADDR): %m");
2874
2875	(void) seteuid(0);
2876
2877#ifdef IP_PORTRANGE
2878	if (ctrl_addr.su_family == AF_INET) {
2879	    on = restricted_data_ports ? IP_PORTRANGE_HIGH
2880				       : IP_PORTRANGE_DEFAULT;
2881
2882	    if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE,
2883			    &on, sizeof(on)) < 0)
2884		    goto pasv_error;
2885	}
2886#endif
2887#ifdef IPV6_PORTRANGE
2888	if (ctrl_addr.su_family == AF_INET6) {
2889	    on = restricted_data_ports ? IPV6_PORTRANGE_HIGH
2890				       : IPV6_PORTRANGE_DEFAULT;
2891
2892	    if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE,
2893			    &on, sizeof(on)) < 0)
2894		    goto pasv_error;
2895	}
2896#endif
2897
2898	pasv_addr = ctrl_addr;
2899	pasv_addr.su_port = 0;
2900	if (bind(pdata, (struct sockaddr *)&pasv_addr, pasv_addr.su_len) < 0)
2901		goto pasv_error;
2902
2903	(void) seteuid(pw->pw_uid);
2904
2905	len = sizeof(pasv_addr);
2906	if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0)
2907		goto pasv_error;
2908	if (listen(pdata, 1) < 0)
2909		goto pasv_error;
2910	if (pasv_addr.su_family == AF_INET)
2911		a = (char *) &pasv_addr.su_sin.sin_addr;
2912	else if (pasv_addr.su_family == AF_INET6 &&
2913		 IN6_IS_ADDR_V4MAPPED(&pasv_addr.su_sin6.sin6_addr))
2914		a = (char *) &pasv_addr.su_sin6.sin6_addr.s6_addr[12];
2915	else
2916		goto pasv_error;
2917
2918	p = (char *) &pasv_addr.su_port;
2919
2920#define UC(b) (((int) b) & 0xff)
2921
2922	reply(227, "Entering Passive Mode (%d,%d,%d,%d,%d,%d)", UC(a[0]),
2923		UC(a[1]), UC(a[2]), UC(a[3]), UC(p[0]), UC(p[1]));
2924	return;
2925
2926pasv_error:
2927	(void) seteuid(pw->pw_uid);
2928	(void) close(pdata);
2929	pdata = -1;
2930	perror_reply(425, "Can't open passive connection");
2931	return;
2932}
2933
2934/*
2935 * Long Passive defined in RFC 1639.
2936 *     228 Entering Long Passive Mode
2937 *         (af, hal, h1, h2, h3,..., pal, p1, p2...)
2938 */
2939
2940void
2941long_passive(char *cmd, int pf)
2942{
2943	socklen_t len;
2944	int on;
2945	char *p, *a;
2946
2947	if (pdata >= 0)		/* close old port if one set */
2948		close(pdata);
2949
2950	if (pf != PF_UNSPEC) {
2951		if (ctrl_addr.su_family != pf) {
2952			switch (ctrl_addr.su_family) {
2953			case AF_INET:
2954				pf = 1;
2955				break;
2956			case AF_INET6:
2957				pf = 2;
2958				break;
2959			default:
2960				pf = 0;
2961				break;
2962			}
2963			/*
2964			 * XXX
2965			 * only EPRT/EPSV ready clients will understand this
2966			 */
2967			if (strcmp(cmd, "EPSV") == 0 && pf) {
2968				reply(522, "Network protocol mismatch, "
2969					"use (%d)", pf);
2970			} else
2971				reply(501, "Network protocol mismatch."); /*XXX*/
2972
2973			return;
2974		}
2975	}
2976
2977	pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
2978	if (pdata < 0) {
2979		perror_reply(425, "Can't open passive connection");
2980		return;
2981	}
2982	on = 1;
2983	if (setsockopt(pdata, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) < 0)
2984		syslog(LOG_WARNING, "pdata setsockopt (SO_REUSEADDR): %m");
2985
2986	(void) seteuid(0);
2987
2988	pasv_addr = ctrl_addr;
2989	pasv_addr.su_port = 0;
2990	len = pasv_addr.su_len;
2991
2992#ifdef IP_PORTRANGE
2993	if (ctrl_addr.su_family == AF_INET) {
2994	    on = restricted_data_ports ? IP_PORTRANGE_HIGH
2995				       : IP_PORTRANGE_DEFAULT;
2996
2997	    if (setsockopt(pdata, IPPROTO_IP, IP_PORTRANGE,
2998			    &on, sizeof(on)) < 0)
2999		    goto pasv_error;
3000	}
3001#endif
3002#ifdef IPV6_PORTRANGE
3003	if (ctrl_addr.su_family == AF_INET6) {
3004	    on = restricted_data_ports ? IPV6_PORTRANGE_HIGH
3005				       : IPV6_PORTRANGE_DEFAULT;
3006
3007	    if (setsockopt(pdata, IPPROTO_IPV6, IPV6_PORTRANGE,
3008			    &on, sizeof(on)) < 0)
3009		    goto pasv_error;
3010	}
3011#endif
3012
3013	if (bind(pdata, (struct sockaddr *)&pasv_addr, len) < 0)
3014		goto pasv_error;
3015
3016	(void) seteuid(pw->pw_uid);
3017
3018	if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0)
3019		goto pasv_error;
3020	if (listen(pdata, 1) < 0)
3021		goto pasv_error;
3022
3023#define UC(b) (((int) b) & 0xff)
3024
3025	if (strcmp(cmd, "LPSV") == 0) {
3026		p = (char *)&pasv_addr.su_port;
3027		switch (pasv_addr.su_family) {
3028		case AF_INET:
3029			a = (char *) &pasv_addr.su_sin.sin_addr;
3030		v4_reply:
3031			reply(228,
3032"Entering Long Passive Mode (%d,%d,%d,%d,%d,%d,%d,%d,%d)",
3033			      4, 4, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
3034			      2, UC(p[0]), UC(p[1]));
3035			return;
3036		case AF_INET6:
3037			if (IN6_IS_ADDR_V4MAPPED(&pasv_addr.su_sin6.sin6_addr)) {
3038				a = (char *) &pasv_addr.su_sin6.sin6_addr.s6_addr[12];
3039				goto v4_reply;
3040			}
3041			a = (char *) &pasv_addr.su_sin6.sin6_addr;
3042			reply(228,
3043"Entering Long Passive Mode "
3044"(%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d)",
3045			      6, 16, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
3046			      UC(a[4]), UC(a[5]), UC(a[6]), UC(a[7]),
3047			      UC(a[8]), UC(a[9]), UC(a[10]), UC(a[11]),
3048			      UC(a[12]), UC(a[13]), UC(a[14]), UC(a[15]),
3049			      2, UC(p[0]), UC(p[1]));
3050			return;
3051		}
3052	} else if (strcmp(cmd, "EPSV") == 0) {
3053		switch (pasv_addr.su_family) {
3054		case AF_INET:
3055		case AF_INET6:
3056			reply(229, "Entering Extended Passive Mode (|||%d|)",
3057				ntohs(pasv_addr.su_port));
3058			return;
3059		}
3060	} else {
3061		/* more proper error code? */
3062	}
3063
3064pasv_error:
3065	(void) seteuid(pw->pw_uid);
3066	(void) close(pdata);
3067	pdata = -1;
3068	perror_reply(425, "Can't open passive connection");
3069	return;
3070}
3071
3072/*
3073 * Generate unique name for file with basename "local"
3074 * and open the file in order to avoid possible races.
3075 * Try "local" first, then "local.1", "local.2" etc, up to "local.99".
3076 * Return descriptor to the file, set "name" to its name.
3077 *
3078 * Generates failure reply on error.
3079 */
3080static int
3081guniquefd(char *local, char **name)
3082{
3083	static char new[MAXPATHLEN];
3084	struct stat st;
3085	char *cp;
3086	int count;
3087	int fd;
3088
3089	cp = strrchr(local, '/');
3090	if (cp)
3091		*cp = '\0';
3092	if (stat(cp ? local : ".", &st) < 0) {
3093		perror_reply(553, cp ? local : ".");
3094		return (-1);
3095	}
3096	if (cp) {
3097		/*
3098		 * Let not overwrite dirname with counter suffix.
3099		 * -4 is for /nn\0
3100		 * In this extreme case dot won't be put in front of suffix.
3101		 */
3102		if (strlen(local) > sizeof(new) - 4) {
3103			reply(553, "Pathname too long.");
3104			return (-1);
3105		}
3106		*cp = '/';
3107	}
3108	/* -4 is for the .nn<null> we put on the end below */
3109	(void) snprintf(new, sizeof(new) - 4, "%s", local);
3110	cp = new + strlen(new);
3111	/*
3112	 * Don't generate dotfile unless requested explicitly.
3113	 * This covers the case when basename gets truncated off
3114	 * by buffer size.
3115	 */
3116	if (cp > new && cp[-1] != '/')
3117		*cp++ = '.';
3118	for (count = 0; count < 100; count++) {
3119		/* At count 0 try unmodified name */
3120		if (count)
3121			(void)sprintf(cp, "%d", count);
3122		if ((fd = open(count ? new : local,
3123		    O_RDWR | O_CREAT | O_EXCL, 0666)) >= 0) {
3124			*name = count ? new : local;
3125			return (fd);
3126		}
3127		if (errno != EEXIST) {
3128			perror_reply(553, count ? new : local);
3129			return (-1);
3130		}
3131	}
3132	reply(452, "Unique file name cannot be created.");
3133	return (-1);
3134}
3135
3136/*
3137 * Format and send reply containing system error number.
3138 */
3139void
3140perror_reply(int code, char *string)
3141{
3142
3143	reply(code, "%s: %s.", string, strerror(errno));
3144}
3145
3146static char *onefile[] = {
3147	"",
3148	0
3149};
3150
3151void
3152send_file_list(char *whichf)
3153{
3154	struct stat st;
3155	DIR *dirp = NULL;
3156	struct dirent *dir;
3157	FILE *dout = NULL;
3158	char **dirlist, *dirname;
3159	int simple = 0;
3160	int freeglob = 0;
3161	glob_t gl;
3162
3163	if (strpbrk(whichf, "~{[*?") != NULL) {
3164		int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE;
3165
3166		memset(&gl, 0, sizeof(gl));
3167		gl.gl_matchc = MAXGLOBARGS;
3168		flags |= GLOB_LIMIT;
3169		freeglob = 1;
3170		if (glob(whichf, flags, 0, &gl)) {
3171			reply(550, "No matching files found.");
3172			goto out;
3173		} else if (gl.gl_pathc == 0) {
3174			errno = ENOENT;
3175			perror_reply(550, whichf);
3176			goto out;
3177		}
3178		dirlist = gl.gl_pathv;
3179	} else {
3180		onefile[0] = whichf;
3181		dirlist = onefile;
3182		simple = 1;
3183	}
3184
3185	while ((dirname = *dirlist++)) {
3186		if (stat(dirname, &st) < 0) {
3187			/*
3188			 * If user typed "ls -l", etc, and the client
3189			 * used NLST, do what the user meant.
3190			 */
3191			if (dirname[0] == '-' && *dirlist == NULL &&
3192			    dout == NULL)
3193				retrieve(_PATH_LS " %s", dirname);
3194			else
3195				perror_reply(550, whichf);
3196			goto out;
3197		}
3198
3199		if (S_ISREG(st.st_mode)) {
3200			if (dout == NULL) {
3201				dout = dataconn("file list", -1, "w");
3202				if (dout == NULL)
3203					goto out;
3204				STARTXFER;
3205			}
3206			START_UNSAFE;
3207			fprintf(dout, "%s%s\n", dirname,
3208				type == TYPE_A ? "\r" : "");
3209			END_UNSAFE;
3210			if (ferror(dout))
3211				goto data_err;
3212			byte_count += strlen(dirname) +
3213				      (type == TYPE_A ? 2 : 1);
3214			CHECKOOB(goto abrt);
3215			continue;
3216		} else if (!S_ISDIR(st.st_mode))
3217			continue;
3218
3219		if ((dirp = opendir(dirname)) == NULL)
3220			continue;
3221
3222		while ((dir = readdir(dirp)) != NULL) {
3223			char nbuf[MAXPATHLEN];
3224
3225			CHECKOOB(goto abrt);
3226
3227			if (dir->d_name[0] == '.' && dir->d_namlen == 1)
3228				continue;
3229			if (dir->d_name[0] == '.' && dir->d_name[1] == '.' &&
3230			    dir->d_namlen == 2)
3231				continue;
3232
3233			snprintf(nbuf, sizeof(nbuf),
3234				"%s/%s", dirname, dir->d_name);
3235
3236			/*
3237			 * We have to do a stat to insure it's
3238			 * not a directory or special file.
3239			 */
3240			if (simple || (stat(nbuf, &st) == 0 &&
3241			    S_ISREG(st.st_mode))) {
3242				if (dout == NULL) {
3243					dout = dataconn("file list", -1, "w");
3244					if (dout == NULL)
3245						goto out;
3246					STARTXFER;
3247				}
3248				START_UNSAFE;
3249				if (nbuf[0] == '.' && nbuf[1] == '/')
3250					fprintf(dout, "%s%s\n", &nbuf[2],
3251						type == TYPE_A ? "\r" : "");
3252				else
3253					fprintf(dout, "%s%s\n", nbuf,
3254						type == TYPE_A ? "\r" : "");
3255				END_UNSAFE;
3256				if (ferror(dout))
3257					goto data_err;
3258				byte_count += strlen(nbuf) +
3259					      (type == TYPE_A ? 2 : 1);
3260				CHECKOOB(goto abrt);
3261			}
3262		}
3263		(void) closedir(dirp);
3264		dirp = NULL;
3265	}
3266
3267	if (dout == NULL)
3268		reply(550, "No files found.");
3269	else if (ferror(dout))
3270data_err:	perror_reply(550, "Data connection");
3271	else
3272		reply(226, "Transfer complete.");
3273out:
3274	if (dout) {
3275		ENDXFER;
3276abrt:
3277		(void) fclose(dout);
3278		data = -1;
3279		pdata = -1;
3280	}
3281	if (dirp)
3282		(void) closedir(dirp);
3283	if (freeglob) {
3284		freeglob = 0;
3285		globfree(&gl);
3286	}
3287}
3288
3289void
3290reapchild(int signo)
3291{
3292	while (waitpid(-1, NULL, WNOHANG) > 0);
3293}
3294
3295#ifdef OLD_SETPROCTITLE
3296/*
3297 * Clobber argv so ps will show what we're doing.  (Stolen from sendmail.)
3298 * Warning, since this is usually started from inetd.conf, it often doesn't
3299 * have much of an environment or arglist to overwrite.
3300 */
3301void
3302setproctitle(const char *fmt, ...)
3303{
3304	int i;
3305	va_list ap;
3306	char *p, *bp, ch;
3307	char buf[LINE_MAX];
3308
3309	va_start(ap, fmt);
3310	(void)vsnprintf(buf, sizeof(buf), fmt, ap);
3311
3312	/* make ps print our process name */
3313	p = Argv[0];
3314	*p++ = '-';
3315
3316	i = strlen(buf);
3317	if (i > LastArgv - p - 2) {
3318		i = LastArgv - p - 2;
3319		buf[i] = '\0';
3320	}
3321	bp = buf;
3322	while (ch = *bp++)
3323		if (ch != '\n' && ch != '\r')
3324			*p++ = ch;
3325	while (p < LastArgv)
3326		*p++ = ' ';
3327}
3328#endif /* OLD_SETPROCTITLE */
3329
3330static void
3331appendf(char **strp, char *fmt, ...)
3332{
3333	va_list ap;
3334	char *ostr, *p;
3335
3336	va_start(ap, fmt);
3337	vasprintf(&p, fmt, ap);
3338	va_end(ap);
3339	if (p == NULL)
3340		fatalerror("Ran out of memory.");
3341	if (*strp == NULL)
3342		*strp = p;
3343	else {
3344		ostr = *strp;
3345		asprintf(strp, "%s%s", ostr, p);
3346		if (*strp == NULL)
3347			fatalerror("Ran out of memory.");
3348		free(ostr);
3349	}
3350}
3351
3352static void
3353logcmd(char *cmd, char *file1, char *file2, off_t cnt)
3354{
3355	char *msg = NULL;
3356	char wd[MAXPATHLEN + 1];
3357
3358	if (logging <= 1)
3359		return;
3360
3361	if (getcwd(wd, sizeof(wd) - 1) == NULL)
3362		strcpy(wd, strerror(errno));
3363
3364	appendf(&msg, "%s", cmd);
3365	if (file1)
3366		appendf(&msg, " %s", file1);
3367	if (file2)
3368		appendf(&msg, " %s", file2);
3369	if (cnt >= 0)
3370		appendf(&msg, " = %jd bytes", (intmax_t)cnt);
3371	appendf(&msg, " (wd: %s", wd);
3372	if (guest || dochroot)
3373		appendf(&msg, "; chrooted");
3374	appendf(&msg, ")");
3375	syslog(LOG_INFO, "%s", msg);
3376	free(msg);
3377}
3378
3379static void
3380logxfer(char *name, off_t size, time_t start)
3381{
3382	char buf[MAXPATHLEN + 1024];
3383	char path[MAXPATHLEN + 1];
3384	time_t now;
3385
3386	if (statfd >= 0) {
3387		time(&now);
3388		if (realpath(name, path) == NULL) {
3389			syslog(LOG_NOTICE, "realpath failed on %s: %m", path);
3390			return;
3391		}
3392		snprintf(buf, sizeof(buf), "%.20s!%s!%s!%s!%jd!%ld\n",
3393			ctime(&now)+4, ident, remotehost,
3394			path, (intmax_t)size,
3395			(long)(now - start + (now == start)));
3396		write(statfd, buf, strlen(buf));
3397	}
3398}
3399
3400static char *
3401doublequote(char *s)
3402{
3403	int n;
3404	char *p, *s2;
3405
3406	for (p = s, n = 0; *p; p++)
3407		if (*p == '"')
3408			n++;
3409
3410	if ((s2 = malloc(p - s + n + 1)) == NULL)
3411		return (NULL);
3412
3413	for (p = s2; *s; s++, p++) {
3414		if ((*p = *s) == '"')
3415			*(++p) = '"';
3416	}
3417	*p = '\0';
3418
3419	return (s2);
3420}
3421
3422/* setup server socket for specified address family */
3423/* if af is PF_UNSPEC more than one socket may be returned */
3424/* the returned list is dynamically allocated, so caller needs to free it */
3425static int *
3426socksetup(int af, char *bindname, const char *bindport)
3427{
3428	struct addrinfo hints, *res, *r;
3429	int error, maxs, *s, *socks;
3430	const int on = 1;
3431
3432	memset(&hints, 0, sizeof(hints));
3433	hints.ai_flags = AI_PASSIVE;
3434	hints.ai_family = af;
3435	hints.ai_socktype = SOCK_STREAM;
3436	error = getaddrinfo(bindname, bindport, &hints, &res);
3437	if (error) {
3438		syslog(LOG_ERR, "%s", gai_strerror(error));
3439		if (error == EAI_SYSTEM)
3440			syslog(LOG_ERR, "%s", strerror(errno));
3441		return NULL;
3442	}
3443
3444	/* Count max number of sockets we may open */
3445	for (maxs = 0, r = res; r; r = r->ai_next, maxs++)
3446		;
3447	socks = malloc((maxs + 1) * sizeof(int));
3448	if (!socks) {
3449		freeaddrinfo(res);
3450		syslog(LOG_ERR, "couldn't allocate memory for sockets");
3451		return NULL;
3452	}
3453
3454	*socks = 0;   /* num of sockets counter at start of array */
3455	s = socks + 1;
3456	for (r = res; r; r = r->ai_next) {
3457		*s = socket(r->ai_family, r->ai_socktype, r->ai_protocol);
3458		if (*s < 0) {
3459			syslog(LOG_DEBUG, "control socket: %m");
3460			continue;
3461		}
3462		if (setsockopt(*s, SOL_SOCKET, SO_REUSEADDR,
3463		    &on, sizeof(on)) < 0)
3464			syslog(LOG_WARNING,
3465			    "control setsockopt (SO_REUSEADDR): %m");
3466		if (r->ai_family == AF_INET6) {
3467			if (setsockopt(*s, IPPROTO_IPV6, IPV6_V6ONLY,
3468			    &on, sizeof(on)) < 0)
3469				syslog(LOG_WARNING,
3470				    "control setsockopt (IPV6_V6ONLY): %m");
3471		}
3472		if (bind(*s, r->ai_addr, r->ai_addrlen) < 0) {
3473			syslog(LOG_DEBUG, "control bind: %m");
3474			close(*s);
3475			continue;
3476		}
3477		(*socks)++;
3478		s++;
3479	}
3480
3481	if (res)
3482		freeaddrinfo(res);
3483
3484	if (*socks == 0) {
3485		syslog(LOG_ERR, "control socket: Couldn't bind to any socket");
3486		free(socks);
3487		return NULL;
3488	}
3489	return(socks);
3490}
3491