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ftpd.c revision 1.185
      1 /*	$NetBSD: ftpd.c,v 1.185 2008/06/09 00:33:39 lukem Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1997-2008 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Luke Mewburn.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     29  * POSSIBILITY OF SUCH DAMAGE.
     30  */
     31 
     32 /*
     33  * Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994
     34  *	The Regents of the University of California.  All rights reserved.
     35  *
     36  * Redistribution and use in source and binary forms, with or without
     37  * modification, are permitted provided that the following conditions
     38  * are met:
     39  * 1. Redistributions of source code must retain the above copyright
     40  *    notice, this list of conditions and the following disclaimer.
     41  * 2. Redistributions in binary form must reproduce the above copyright
     42  *    notice, this list of conditions and the following disclaimer in the
     43  *    documentation and/or other materials provided with the distribution.
     44  * 3. Neither the name of the University nor the names of its contributors
     45  *    may be used to endorse or promote products derived from this software
     46  *    without specific prior written permission.
     47  *
     48  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     49  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     50  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     51  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     52  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     53  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     54  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     55  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     56  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     57  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     58  * SUCH DAMAGE.
     59  */
     60 
     61 /*
     62  * Copyright (C) 1997 and 1998 WIDE Project.
     63  * All rights reserved.
     64  *
     65  * Redistribution and use in source and binary forms, with or without
     66  * modification, are permitted provided that the following conditions
     67  * are met:
     68  * 1. Redistributions of source code must retain the above copyright
     69  *    notice, this list of conditions and the following disclaimer.
     70  * 2. Redistributions in binary form must reproduce the above copyright
     71  *    notice, this list of conditions and the following disclaimer in the
     72  *    documentation and/or other materials provided with the distribution.
     73  * 3. Neither the name of the project nor the names of its contributors
     74  *    may be used to endorse or promote products derived from this software
     75  *    without specific prior written permission.
     76  *
     77  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
     78  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     79  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     80  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
     81  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     82  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     83  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     84  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     85  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     86  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     87  * SUCH DAMAGE.
     88  */
     89 
     90 #include <sys/cdefs.h>
     91 #ifndef lint
     92 __COPYRIGHT(
     93 "@(#) Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994\n\
     94 	The Regents of the University of California.  All rights reserved.\n");
     95 #endif /* not lint */
     96 
     97 #ifndef lint
     98 #if 0
     99 static char sccsid[] = "@(#)ftpd.c	8.5 (Berkeley) 4/28/95";
    100 #else
    101 __RCSID("$NetBSD: ftpd.c,v 1.185 2008/06/09 00:33:39 lukem Exp $");
    102 #endif
    103 #endif /* not lint */
    104 
    105 /*
    106  * FTP server.
    107  */
    108 #include <sys/param.h>
    109 #include <sys/stat.h>
    110 #include <sys/ioctl.h>
    111 #include <sys/socket.h>
    112 #include <sys/wait.h>
    113 #include <sys/mman.h>
    114 #include <sys/resource.h>
    115 
    116 #include <netinet/in.h>
    117 #include <netinet/in_systm.h>
    118 #include <netinet/ip.h>
    119 
    120 #define	FTP_NAMES
    121 #include <arpa/ftp.h>
    122 #include <arpa/inet.h>
    123 #include <arpa/telnet.h>
    124 
    125 #include <ctype.h>
    126 #include <dirent.h>
    127 #include <err.h>
    128 #include <errno.h>
    129 #include <fcntl.h>
    130 #include <fnmatch.h>
    131 #include <glob.h>
    132 #include <grp.h>
    133 #include <limits.h>
    134 #include <netdb.h>
    135 #include <pwd.h>
    136 #include <poll.h>
    137 #include <signal.h>
    138 #include <stdarg.h>
    139 #include <stdio.h>
    140 #include <stdlib.h>
    141 #include <string.h>
    142 #include <syslog.h>
    143 #include <time.h>
    144 #include <tzfile.h>
    145 #include <unistd.h>
    146 #include <util.h>
    147 #ifdef SUPPORT_UTMP
    148 #include <utmp.h>
    149 #endif
    150 #ifdef SUPPORT_UTMPX
    151 #include <utmpx.h>
    152 #endif
    153 #ifdef SKEY
    154 #include <skey.h>
    155 #endif
    156 #ifdef KERBEROS5
    157 #include <com_err.h>
    158 #include <krb5/krb5.h>
    159 #endif
    160 
    161 #ifdef	LOGIN_CAP
    162 #include <login_cap.h>
    163 #endif
    164 
    165 #ifdef USE_PAM
    166 #include <security/pam_appl.h>
    167 #endif
    168 
    169 #define	GLOBAL
    170 #include "extern.h"
    171 #include "pathnames.h"
    172 #include "version.h"
    173 
    174 static sig_atomic_t	transflag;
    175 static sig_atomic_t	urgflag;
    176 
    177 int	data;
    178 int	Dflag;
    179 int	sflag;
    180 int	stru;			/* avoid C keyword */
    181 int	mode;
    182 int	dataport;		/* use specific data port */
    183 int	dopidfile;		/* maintain pid file */
    184 int	doutmp;			/* update utmp file */
    185 int	dowtmp;			/* update wtmp file */
    186 int	doxferlog;		/* syslog/write wu-ftpd style xferlog entries */
    187 int	xferlogfd;		/* fd to write wu-ftpd xferlog entries to */
    188 int	getnameopts;		/* flags for use with getname() */
    189 int	dropprivs;		/* if privileges should or have been dropped */
    190 int	mapped;			/* IPv4 connection on AF_INET6 socket */
    191 off_t	file_size;
    192 off_t	byte_count;
    193 static char ttyline[20];
    194 
    195 #ifdef USE_PAM
    196 static int	auth_pam(void);
    197 pam_handle_t	*pamh = NULL;
    198 #endif
    199 
    200 #ifdef SUPPORT_UTMP
    201 static struct utmp utmp;	/* for utmp */
    202 #endif
    203 #ifdef SUPPORT_UTMPX
    204 static struct utmpx utmpx;	/* for utmpx */
    205 #endif
    206 
    207 static const char *anondir = NULL;
    208 static const char *confdir = _DEFAULT_CONFDIR;
    209 
    210 static char	*curname;		/* current USER name */
    211 static size_t	curname_len;		/* length of curname (include NUL) */
    212 
    213 #if defined(KERBEROS) || defined(KERBEROS5)
    214 int	has_ccache = 0;
    215 int	notickets = 1;
    216 char	*krbtkfile_env = NULL;
    217 char	*tty = ttyline;
    218 int	login_krb5_forwardable_tgt = 0;
    219 #endif
    220 
    221 int epsvall = 0;
    222 
    223 /*
    224  * Timeout intervals for retrying connections
    225  * to hosts that don't accept PORT cmds.  This
    226  * is a kludge, but given the problems with TCP...
    227  */
    228 #define	SWAITMAX	90	/* wait at most 90 seconds */
    229 #define	SWAITINT	5	/* interval between retries */
    230 
    231 int	swaitmax = SWAITMAX;
    232 int	swaitint = SWAITINT;
    233 
    234 enum send_status {
    235 	SS_SUCCESS,
    236 	SS_ABORTED,			/* transfer aborted */
    237 	SS_NO_TRANSFER,			/* no transfer made yet */
    238 	SS_FILE_ERROR,			/* file read error */
    239 	SS_DATA_ERROR			/* data send error */
    240 };
    241 
    242 static int	 bind_pasv_addr(void);
    243 static int	 checkuser(const char *, const char *, int, int, char **);
    244 static int	 checkaccess(const char *);
    245 static int	 checkpassword(const struct passwd *, const char *);
    246 static void	 do_pass(int, int, const char *);
    247 static void	 end_login(void);
    248 static FILE	*getdatasock(const char *);
    249 static char	*gunique(const char *);
    250 static void	 login_utmp(const char *, const char *, const char *,
    251 		     struct sockinet *);
    252 static void	 logremotehost(struct sockinet *);
    253 static void	 lostconn(int);
    254 static void	 toolong(int);
    255 static void	 sigquit(int);
    256 static void	 sigurg(int);
    257 static int	 handleoobcmd(void);
    258 static int	 receive_data(FILE *, FILE *);
    259 static int	 send_data(FILE *, FILE *, const struct stat *, int);
    260 static struct passwd *sgetpwnam(const char *);
    261 static int	 write_data(int, char *, size_t, off_t *, struct timeval *,
    262 		     int);
    263 static enum send_status
    264 		 send_data_with_read(int, int, const struct stat *, int);
    265 static enum send_status
    266 		 send_data_with_mmap(int, int, const struct stat *, int);
    267 static void	 logrusage(const struct rusage *, const struct rusage *);
    268 static void	 logout_utmp(void);
    269 
    270 int	main(int, char *[]);
    271 
    272 #if defined(KERBEROS)
    273 int	klogin(struct passwd *, char *, char *, char *);
    274 void	kdestroy(void);
    275 #endif
    276 #if defined(KERBEROS5)
    277 int	k5login(struct passwd *, char *, char *, char *);
    278 void	k5destroy(void);
    279 #endif
    280 
    281 int
    282 main(int argc, char *argv[])
    283 {
    284 	int		ch, on = 1, tos, keepalive;
    285 	socklen_t	addrlen;
    286 #ifdef KERBEROS5
    287 	krb5_error_code	kerror;
    288 #endif
    289 	char		*p;
    290 	const char	*xferlogname = NULL;
    291 	long		l;
    292 	struct sigaction sa;
    293 	sa_family_t	af = AF_UNSPEC;
    294 
    295 	connections = 1;
    296 	ftpd_debug = 0;
    297 	logging = 0;
    298 	pdata = -1;
    299 	Dflag = 0;
    300 	sflag = 0;
    301 	dataport = 0;
    302 	dopidfile = 1;		/* default: DO use a pid file to count users */
    303 	doutmp = 0;		/* default: Do NOT log to utmp */
    304 	dowtmp = 1;		/* default: DO log to wtmp */
    305 	doxferlog = 0;		/* default: Do NOT syslog xferlog */
    306 	xferlogfd = -1;		/* default: Do NOT write xferlog file */
    307 	getnameopts = 0;	/* default: xlate addrs to name */
    308 	dropprivs = 0;
    309 	mapped = 0;
    310 	usedefault = 1;
    311 	emailaddr = NULL;
    312 	hostname[0] = '\0';
    313 	homedir[0] = '\0';
    314 	gidcount = 0;
    315 	is_oob = 0;
    316 	version = FTPD_VERSION;
    317 
    318 	/*
    319 	 * LOG_NDELAY sets up the logging connection immediately,
    320 	 * necessary for anonymous ftp's that chroot and can't do it later.
    321 	 */
    322 	openlog("ftpd", LOG_PID | LOG_NDELAY, LOG_FTP);
    323 
    324 	while ((ch = getopt(argc, argv,
    325 	    "46a:c:C:Dde:h:HlL:nP:qQrst:T:uUvV:wWX")) != -1) {
    326 		switch (ch) {
    327 		case '4':
    328 			af = AF_INET;
    329 			break;
    330 
    331 		case '6':
    332 			af = AF_INET6;
    333 			break;
    334 
    335 		case 'a':
    336 			anondir = optarg;
    337 			break;
    338 
    339 		case 'c':
    340 			confdir = optarg;
    341 			break;
    342 
    343 		case 'C':
    344 			pw = sgetpwnam(optarg);
    345 			exit(checkaccess(optarg) ? 0 : 1);
    346 			/* NOTREACHED */
    347 
    348 		case 'D':
    349 			Dflag = 1;
    350 			break;
    351 
    352 		case 'd':
    353 		case 'v':		/* deprecated */
    354 			ftpd_debug = 1;
    355 			break;
    356 
    357 		case 'e':
    358 			emailaddr = optarg;
    359 			break;
    360 
    361 		case 'h':
    362 			strlcpy(hostname, optarg, sizeof(hostname));
    363 			break;
    364 
    365 		case 'H':
    366 			if (gethostname(hostname, sizeof(hostname)) == -1)
    367 				hostname[0] = '\0';
    368 			hostname[sizeof(hostname) - 1] = '\0';
    369 			break;
    370 
    371 		case 'l':
    372 			logging++;	/* > 1 == extra logging */
    373 			break;
    374 
    375 		case 'L':
    376 			xferlogname = optarg;
    377 			break;
    378 
    379 		case 'n':
    380 			getnameopts = NI_NUMERICHOST;
    381 			break;
    382 
    383 		case 'P':
    384 			errno = 0;
    385 			p = NULL;
    386 			l = strtol(optarg, &p, 10);
    387 			if (errno || *optarg == '\0' || *p != '\0' ||
    388 			    l < IPPORT_RESERVED ||
    389 			    l > IPPORT_ANONMAX) {
    390 				syslog(LOG_WARNING, "Invalid dataport %s",
    391 				    optarg);
    392 				dataport = 0;
    393 			}
    394 			dataport = (int)l;
    395 			break;
    396 
    397 		case 'q':
    398 			dopidfile = 1;
    399 			break;
    400 
    401 		case 'Q':
    402 			dopidfile = 0;
    403 			break;
    404 
    405 		case 'r':
    406 			dropprivs = 1;
    407 			break;
    408 
    409 		case 's':
    410 			sflag = 1;
    411 			break;
    412 
    413 		case 't':
    414 		case 'T':
    415 			syslog(LOG_WARNING,
    416 			    "-%c has been deprecated in favour of ftpd.conf",
    417 			    ch);
    418 			break;
    419 
    420 		case 'u':
    421 			doutmp = 1;
    422 			break;
    423 
    424 		case 'U':
    425 			doutmp = 0;
    426 			break;
    427 
    428 		case 'V':
    429 			if (EMPTYSTR(optarg) || strcmp(optarg, "-") == 0)
    430 				version = NULL;
    431 			else
    432 				version = ftpd_strdup(optarg);
    433 			break;
    434 
    435 		case 'w':
    436 			dowtmp = 1;
    437 			break;
    438 
    439 		case 'W':
    440 			dowtmp = 0;
    441 			break;
    442 
    443 		case 'X':
    444 			doxferlog |= 1;
    445 			break;
    446 
    447 		default:
    448 			if (optopt == 'a' || optopt == 'C')
    449 				exit(1);
    450 			syslog(LOG_WARNING, "unknown flag -%c ignored", optopt);
    451 			break;
    452 		}
    453 	}
    454 	if (EMPTYSTR(confdir))
    455 		confdir = _DEFAULT_CONFDIR;
    456 
    457 	if (dowtmp) {
    458 #ifdef SUPPORT_UTMPX
    459 		ftpd_initwtmpx();
    460 #endif
    461 #ifdef SUPPORT_UTMP
    462 		ftpd_initwtmp();
    463 #endif
    464 	}
    465 	errno = 0;
    466 	l = sysconf(_SC_LOGIN_NAME_MAX);
    467 	if (l == -1 && errno != 0) {
    468 		syslog(LOG_ERR, "sysconf _SC_LOGIN_NAME_MAX: %m");
    469 		exit(1);
    470 	} else if (l <= 0) {
    471 		syslog(LOG_WARNING, "using conservative LOGIN_NAME_MAX value");
    472 		curname_len = _POSIX_LOGIN_NAME_MAX;
    473 	} else
    474 		curname_len = (size_t)l;
    475 	curname = malloc(curname_len);
    476 	if (curname == NULL) {
    477 		syslog(LOG_ERR, "malloc: %m");
    478 		exit(1);
    479 	}
    480 	curname[0] = '\0';
    481 
    482 	if (Dflag) {
    483 		int error, fd, i, n, *socks;
    484 		struct pollfd *fds;
    485 		struct addrinfo hints, *res, *res0;
    486 
    487 		if (daemon(1, 0) == -1) {
    488 			syslog(LOG_ERR, "failed to daemonize: %m");
    489 			exit(1);
    490 		}
    491 		(void)memset(&sa, 0, sizeof(sa));
    492 		sa.sa_handler = SIG_IGN;
    493 		sa.sa_flags = SA_NOCLDWAIT;
    494 		sigemptyset(&sa.sa_mask);
    495 		(void)sigaction(SIGCHLD, &sa, NULL);
    496 
    497 		(void)memset(&hints, 0, sizeof(hints));
    498 		hints.ai_flags = AI_PASSIVE;
    499 		hints.ai_family = af;
    500 		hints.ai_socktype = SOCK_STREAM;
    501 		error = getaddrinfo(NULL, "ftp", &hints, &res0);
    502 		if (error) {
    503 			syslog(LOG_ERR, "getaddrinfo: %s", gai_strerror(error));
    504 			exit(1);
    505 		}
    506 
    507 		for (n = 0, res = res0; res != NULL; res = res->ai_next)
    508 			n++;
    509 		if (n == 0) {
    510 			syslog(LOG_ERR, "no addresses available");
    511 			exit(1);
    512 		}
    513 		socks = malloc(n * sizeof(int));
    514 		fds = malloc(n * sizeof(struct pollfd));
    515 		if (socks == NULL || fds == NULL) {
    516 			syslog(LOG_ERR, "malloc: %m");
    517 			exit(1);
    518 		}
    519 
    520 		for (n = 0, res = res0; res != NULL; res = res->ai_next) {
    521 			socks[n] = socket(res->ai_family, res->ai_socktype,
    522 			    res->ai_protocol);
    523 			if (socks[n] == -1)
    524 				continue;
    525 			(void)setsockopt(socks[n], SOL_SOCKET, SO_REUSEADDR,
    526 			    &on, sizeof(on));
    527 			if (bind(socks[n], res->ai_addr, res->ai_addrlen)
    528 			    == -1) {
    529 				(void)close(socks[n]);
    530 				continue;
    531 			}
    532 			if (listen(socks[n], 12) == -1) {
    533 				(void)close(socks[n]);
    534 				continue;
    535 			}
    536 
    537 			fds[n].fd = socks[n];
    538 			fds[n].events = POLLIN;
    539 			n++;
    540 		}
    541 		if (n == 0) {
    542 			syslog(LOG_ERR, "%m");
    543 			exit(1);
    544 		}
    545 		freeaddrinfo(res0);
    546 
    547 		if (pidfile(NULL) == -1)
    548 			syslog(LOG_ERR, "failed to write a pid file: %m");
    549 
    550 		for (;;) {
    551 			if (poll(fds, n, INFTIM) == -1) {
    552 				if (errno == EINTR)
    553 					continue;
    554 				syslog(LOG_ERR, "poll: %m");
    555 				exit(1);
    556 			}
    557 			for (i = 0; i < n; i++) {
    558 				if (fds[i].revents & POLLIN) {
    559 					fd = accept(fds[i].fd, NULL, NULL);
    560 					if (fd == -1) {
    561 						syslog(LOG_ERR, "accept: %m");
    562 						continue;
    563 					}
    564 					switch (fork()) {
    565 					case -1:
    566 						syslog(LOG_ERR, "fork: %m");
    567 						break;
    568 					case 0:
    569 						goto child;
    570 						/* NOTREACHED */
    571 					}
    572 					(void)close(fd);
    573 				}
    574 			}
    575 		}
    576  child:
    577 		(void)dup2(fd, STDIN_FILENO);
    578 		(void)dup2(fd, STDOUT_FILENO);
    579 		(void)dup2(fd, STDERR_FILENO);
    580 		for (i = 0; i < n; i++)
    581 			(void)close(socks[i]);
    582 	}
    583 
    584 	memset((char *)&his_addr, 0, sizeof(his_addr));
    585 	addrlen = sizeof(his_addr.si_su);
    586 	if (getpeername(0, (struct sockaddr *)&his_addr.si_su, &addrlen) < 0) {
    587 		syslog(LOG_ERR, "getpeername (%s): %m",argv[0]);
    588 		exit(1);
    589 	}
    590 	his_addr.su_len = addrlen;
    591 	memset((char *)&ctrl_addr, 0, sizeof(ctrl_addr));
    592 	addrlen = sizeof(ctrl_addr.si_su);
    593 	if (getsockname(0, (struct sockaddr *)&ctrl_addr, &addrlen) < 0) {
    594 		syslog(LOG_ERR, "getsockname (%s): %m",argv[0]);
    595 		exit(1);
    596 	}
    597 	ctrl_addr.su_len = addrlen;
    598 #ifdef INET6
    599 	if (his_addr.su_family == AF_INET6
    600 	 && IN6_IS_ADDR_V4MAPPED(&his_addr.su_6addr)) {
    601 #if 1
    602 		/*
    603 		 * IPv4 control connection arrived to AF_INET6 socket.
    604 		 * I hate to do this, but this is the easiest solution.
    605 		 *
    606 		 * The assumption is untrue on SIIT environment.
    607 		 */
    608 		struct sockinet tmp_addr;
    609 		const int off = sizeof(struct in6_addr) - sizeof(struct in_addr);
    610 
    611 		tmp_addr = his_addr;
    612 		memset(&his_addr, 0, sizeof(his_addr));
    613 		his_addr.su_family = AF_INET;
    614 		his_addr.su_len = sizeof(his_addr.si_su.su_sin);
    615 		memcpy(&his_addr.su_addr, &tmp_addr.su_6addr.s6_addr[off],
    616 		    sizeof(his_addr.su_addr));
    617 		his_addr.su_port = tmp_addr.su_port;
    618 
    619 		tmp_addr = ctrl_addr;
    620 		memset(&ctrl_addr, 0, sizeof(ctrl_addr));
    621 		ctrl_addr.su_family = AF_INET;
    622 		ctrl_addr.su_len = sizeof(ctrl_addr.si_su.su_sin);
    623 		memcpy(&ctrl_addr.su_addr, &tmp_addr.su_6addr.s6_addr[off],
    624 		    sizeof(ctrl_addr.su_addr));
    625 		ctrl_addr.su_port = tmp_addr.su_port;
    626 #else
    627 		while (fgets(line, sizeof(line), fd) != NULL) {
    628 			if ((cp = strchr(line, '\n')) != NULL)
    629 				*cp = '\0';
    630 			reply(-530, "%s", line);
    631 		}
    632 		(void) fflush(stdout);
    633 		(void) fclose(fd);
    634 		reply(530,
    635 		    "Connection from IPv4 mapped address is not supported.");
    636 		exit(0);
    637 #endif
    638 
    639 		mapped = 1;
    640 	} else
    641 #endif /* INET6 */
    642 		mapped = 0;
    643 #ifdef IP_TOS
    644 	if (!mapped && his_addr.su_family == AF_INET) {
    645 		tos = IPTOS_LOWDELAY;
    646 		if (setsockopt(0, IPPROTO_IP, IP_TOS, (char *)&tos,
    647 			       sizeof(int)) < 0)
    648 			syslog(LOG_WARNING, "setsockopt (IP_TOS): %m");
    649 	}
    650 #endif
    651 	/* if the hostname hasn't been given, attempt to determine it */
    652 	if (hostname[0] == '\0') {
    653 		if (getnameinfo((struct sockaddr *)&ctrl_addr.si_su,
    654 		    ctrl_addr.su_len, hostname, sizeof(hostname), NULL, 0,
    655 			getnameopts) != 0)
    656 			(void)gethostname(hostname, sizeof(hostname));
    657 		hostname[sizeof(hostname) - 1] = '\0';
    658 	}
    659 
    660 	/* set this here so klogin can use it... */
    661 	(void)snprintf(ttyline, sizeof(ttyline), "ftp%d", getpid());
    662 
    663 	(void) freopen(_PATH_DEVNULL, "w", stderr);
    664 
    665 	memset(&sa, 0, sizeof(sa));
    666 	sa.sa_handler = SIG_DFL;
    667 	sa.sa_flags = SA_RESTART;
    668 	sigemptyset(&sa.sa_mask);
    669 	(void) sigaction(SIGCHLD, &sa, NULL);
    670 
    671 	sa.sa_handler = sigquit;
    672 	sa.sa_flags = SA_RESTART;
    673 	sigfillset(&sa.sa_mask);	/* block all sigs in these handlers */
    674 	(void) sigaction(SIGHUP, &sa, NULL);
    675 	(void) sigaction(SIGINT, &sa, NULL);
    676 	(void) sigaction(SIGQUIT, &sa, NULL);
    677 	(void) sigaction(SIGTERM, &sa, NULL);
    678 	sa.sa_handler = lostconn;
    679 	(void) sigaction(SIGPIPE, &sa, NULL);
    680 	sa.sa_handler = toolong;
    681 	(void) sigaction(SIGALRM, &sa, NULL);
    682 	sa.sa_handler = sigurg;
    683 	(void) sigaction(SIGURG, &sa, NULL);
    684 
    685 	/* Try to handle urgent data inline */
    686 #ifdef SO_OOBINLINE
    687 	if (setsockopt(0, SOL_SOCKET, SO_OOBINLINE, (char *)&on, sizeof(on)) < 0)
    688 		syslog(LOG_WARNING, "setsockopt: %m");
    689 #endif
    690 	/* Set keepalives on the socket to detect dropped connections.  */
    691 #ifdef SO_KEEPALIVE
    692 	keepalive = 1;
    693 	if (setsockopt(0, SOL_SOCKET, SO_KEEPALIVE, (char *)&keepalive,
    694 	    sizeof(int)) < 0)
    695 		syslog(LOG_WARNING, "setsockopt (SO_KEEPALIVE): %m");
    696 #endif
    697 
    698 #ifdef	F_SETOWN
    699 	if (fcntl(fileno(stdin), F_SETOWN, getpid()) == -1)
    700 		syslog(LOG_WARNING, "fcntl F_SETOWN: %m");
    701 #endif
    702 	logremotehost(&his_addr);
    703 	/*
    704 	 * Set up default state
    705 	 */
    706 	data = -1;
    707 	type = TYPE_A;
    708 	form = FORM_N;
    709 	stru = STRU_F;
    710 	mode = MODE_S;
    711 	tmpline[0] = '\0';
    712 	hasyyerrored = 0;
    713 
    714 #ifdef KERBEROS5
    715 	kerror = krb5_init_context(&kcontext);
    716 	if (kerror) {
    717 		syslog(LOG_ERR, "%s when initializing Kerberos context",
    718 		    error_message(kerror));
    719 		exit(0);
    720 	}
    721 #endif /* KERBEROS5 */
    722 
    723 	init_curclass();
    724 	curclass.timeout = 300;		/* 5 minutes, as per login(1) */
    725 	curclass.type = CLASS_REAL;
    726 
    727 	/* If logins are disabled, print out the message. */
    728 	if (display_file(_PATH_NOLOGIN, 530)) {
    729 		reply(530, "System not available.");
    730 		exit(0);
    731 	}
    732 	(void)display_file(conffilename(_NAME_FTPWELCOME), 220);
    733 		/* reply(220,) must follow */
    734 	if (EMPTYSTR(version))
    735 		reply(220, "%s FTP server ready.", hostname);
    736 	else
    737 		reply(220, "%s FTP server (%s) ready.", hostname, version);
    738 
    739 	if (xferlogname != NULL) {
    740 		xferlogfd = open(xferlogname, O_WRONLY | O_APPEND | O_CREAT,
    741 		    0660);
    742 		if (xferlogfd == -1)
    743 			syslog(LOG_WARNING, "open xferlog `%s': %m",
    744 			    xferlogname);
    745 		else
    746 			doxferlog |= 2;
    747 	}
    748 
    749 	ftp_loop();
    750 	/* NOTREACHED */
    751 }
    752 
    753 static void
    754 lostconn(int signo __unused)
    755 {
    756 
    757 	if (ftpd_debug)
    758 		syslog(LOG_DEBUG, "lost connection");
    759 	dologout(1);
    760 }
    761 
    762 static void
    763 toolong(int signo __unused)
    764 {
    765 
    766 		/* XXXSIGRACE */
    767 	reply(421,
    768 	    "Timeout (" LLF " seconds): closing control connection.",
    769 	    (LLT)curclass.timeout);
    770 	if (logging)
    771 		syslog(LOG_INFO, "User %s timed out after " LLF " seconds",
    772 		    (pw ? pw->pw_name : "unknown"), (LLT)curclass.timeout);
    773 	dologout(1);
    774 }
    775 
    776 static void
    777 sigquit(int signo)
    778 {
    779 
    780 	if (ftpd_debug)
    781 		syslog(LOG_DEBUG, "got signal %d", signo);
    782 	dologout(1);
    783 }
    784 
    785 static void
    786 sigurg(int signo __unused)
    787 {
    788 
    789 	urgflag = 1;
    790 }
    791 
    792 
    793 /*
    794  * Save the result of a getpwnam.  Used for USER command, since
    795  * the data returned must not be clobbered by any other command
    796  * (e.g., globbing).
    797  */
    798 static struct passwd *
    799 sgetpwnam(const char *name)
    800 {
    801 	static struct passwd save;
    802 	struct passwd *p;
    803 
    804 	if ((p = getpwnam(name)) == NULL)
    805 		return (p);
    806 	if (save.pw_name) {
    807 		free((char *)save.pw_name);
    808 		memset(save.pw_passwd, 0, strlen(save.pw_passwd));
    809 		free((char *)save.pw_passwd);
    810 		free((char *)save.pw_gecos);
    811 		free((char *)save.pw_dir);
    812 		free((char *)save.pw_shell);
    813 	}
    814 	save = *p;
    815 	save.pw_name = ftpd_strdup(p->pw_name);
    816 	save.pw_passwd = ftpd_strdup(p->pw_passwd);
    817 	save.pw_gecos = ftpd_strdup(p->pw_gecos);
    818 	save.pw_dir = ftpd_strdup(p->pw_dir);
    819 	save.pw_shell = ftpd_strdup(p->pw_shell);
    820 	return (&save);
    821 }
    822 
    823 static int	login_attempts;	/* number of failed login attempts */
    824 static int	askpasswd;	/* had USER command, ask for PASSwd */
    825 static int	permitted;	/* USER permitted */
    826 
    827 /*
    828  * USER command.
    829  * Sets global passwd pointer pw if named account exists and is acceptable;
    830  * sets askpasswd if a PASS command is expected.  If logged in previously,
    831  * need to reset state.  If name is "ftp" or "anonymous", the name is not in
    832  * _NAME_FTPUSERS, and ftp account exists, set guest and pw, then just return.
    833  * If account doesn't exist, ask for passwd anyway.  Otherwise, check user
    834  * requesting login privileges.  Disallow anyone who does not have a standard
    835  * shell as returned by getusershell().  Disallow anyone mentioned in the file
    836  * _NAME_FTPUSERS to allow people such as root and uucp to be avoided.
    837  */
    838 void
    839 user(const char *name)
    840 {
    841 	char	*class;
    842 #ifdef	LOGIN_CAP
    843 	login_cap_t *lc = NULL;
    844 #endif
    845 #ifdef USE_PAM
    846 	int e;
    847 #endif
    848 
    849 	class = NULL;
    850 	if (logged_in) {
    851 		switch (curclass.type) {
    852 		case CLASS_GUEST:
    853 			reply(530, "Can't change user from guest login.");
    854 			return;
    855 		case CLASS_CHROOT:
    856 			reply(530, "Can't change user from chroot user.");
    857 			return;
    858 		case CLASS_REAL:
    859 			if (dropprivs) {
    860 				reply(530, "Can't change user.");
    861 				return;
    862 			}
    863 			end_login();
    864 			break;
    865 		default:
    866 			abort();
    867 		}
    868 	}
    869 
    870 #if defined(KERBEROS)
    871 	kdestroy();
    872 #endif
    873 #if defined(KERBEROS5)
    874 	k5destroy();
    875 #endif
    876 
    877 	curclass.type = CLASS_REAL;
    878 	askpasswd = 0;
    879 	permitted = 0;
    880 
    881 	if (strcmp(name, "ftp") == 0 || strcmp(name, "anonymous") == 0) {
    882 			/* need `pw' setup for checkaccess() and checkuser () */
    883 		if ((pw = sgetpwnam("ftp")) == NULL)
    884 			reply(530, "User %s unknown.", name);
    885 		else if (! checkaccess("ftp") || ! checkaccess("anonymous"))
    886 			reply(530, "User %s access denied.", name);
    887 		else {
    888 			curclass.type = CLASS_GUEST;
    889 			askpasswd = 1;
    890 			reply(331,
    891 			    "Guest login ok, type your name as password.");
    892 		}
    893 		if (!askpasswd) {
    894 			if (logging)
    895 				syslog(LOG_NOTICE,
    896 				    "ANONYMOUS FTP LOGIN REFUSED FROM %s",
    897 				    remotehost);
    898 			end_login();
    899 			goto cleanup_user;
    900 		}
    901 		name = "ftp";
    902 	} else
    903 		pw = sgetpwnam(name);
    904 
    905 	strlcpy(curname, name, curname_len);
    906 
    907 			/* check user in /etc/ftpusers, and setup class */
    908 	permitted = checkuser(_NAME_FTPUSERS, curname, 1, 0, &class);
    909 
    910 			/* check user in /etc/ftpchroot */
    911 #ifdef	LOGIN_CAP
    912 	lc = login_getpwclass(pw);
    913 #endif
    914 	if (checkuser(_NAME_FTPCHROOT, curname, 0, 0, NULL)
    915 #ifdef	LOGIN_CAP	/* Allow login.conf configuration as well */
    916 	    || login_getcapbool(lc, "ftp-chroot", 0)
    917 #endif
    918 	) {
    919 		if (curclass.type == CLASS_GUEST) {
    920 			syslog(LOG_NOTICE,
    921 	    "Can't change guest user to chroot class; remove entry in %s",
    922 			    _NAME_FTPCHROOT);
    923 			exit(1);
    924 		}
    925 		curclass.type = CLASS_CHROOT;
    926 	}
    927 
    928 			/* determine default class */
    929 	if (class == NULL) {
    930 		switch (curclass.type) {
    931 		case CLASS_GUEST:
    932 			class = ftpd_strdup("guest");
    933 			break;
    934 		case CLASS_CHROOT:
    935 			class = ftpd_strdup("chroot");
    936 			break;
    937 		case CLASS_REAL:
    938 			class = ftpd_strdup("real");
    939 			break;
    940 		default:
    941 			syslog(LOG_ERR, "unknown curclass.type %d; aborting",
    942 			    curclass.type);
    943 			abort();
    944 		}
    945 	}
    946 			/* parse ftpd.conf, setting up various parameters */
    947 	parse_conf(class);
    948 			/* if not guest user, check for valid shell */
    949 	if (pw == NULL)
    950 		permitted = 0;
    951 	else {
    952 		const char	*cp, *shell;
    953 
    954 		if ((shell = pw->pw_shell) == NULL || *shell == 0)
    955 			shell = _PATH_BSHELL;
    956 		while ((cp = getusershell()) != NULL)
    957 			if (strcmp(cp, shell) == 0)
    958 				break;
    959 		endusershell();
    960 		if (cp == NULL && curclass.type != CLASS_GUEST)
    961 			permitted = 0;
    962 	}
    963 
    964 			/* deny quickly (after USER not PASS) if requested */
    965 	if (CURCLASS_FLAGS_ISSET(denyquick) && !permitted) {
    966 		reply(530, "User %s may not use FTP.", curname);
    967 		if (logging)
    968 			syslog(LOG_NOTICE, "FTP LOGIN REFUSED FROM %s, %s",
    969 			    remotehost, curname);
    970 		end_login();
    971 		goto cleanup_user;
    972 	}
    973 
    974 			/* if haven't asked yet (i.e, not anon), ask now */
    975 	if (!askpasswd) {
    976 		askpasswd = 1;
    977 #ifdef USE_PAM
    978 		e = auth_pam();		/* this does reply(331, ...) */
    979 		do_pass(1, e, "");
    980 		goto cleanup_user;
    981 #else /* !USE_PAM */
    982 #ifdef SKEY
    983 		if (skey_haskey(curname) == 0) {
    984 			const char *myskey;
    985 
    986 			myskey = skey_keyinfo(curname);
    987 			reply(331, "Password [ %s ] required for %s.",
    988 			    myskey ? myskey : "error getting challenge",
    989 			    curname);
    990 		} else
    991 #endif
    992 			reply(331, "Password required for %s.", curname);
    993 #endif /* !USE_PAM */
    994 	}
    995 
    996  cleanup_user:
    997 #ifdef LOGIN_CAP
    998 	login_close(lc);
    999 #endif
   1000 	/*
   1001 	 * Delay before reading passwd after first failed
   1002 	 * attempt to slow down passwd-guessing programs.
   1003 	 */
   1004 	if (login_attempts)
   1005 		sleep((unsigned) login_attempts);
   1006 
   1007 	if (class)
   1008 		free(class);
   1009 }
   1010 
   1011 /*
   1012  * Determine whether something is to happen (allow access, chroot)
   1013  * for a user. Each line is a shell-style glob followed by
   1014  * `yes' or `no'.
   1015  *
   1016  * For backward compatibility, `allow' and `deny' are synonymns
   1017  * for `yes' and `no', respectively.
   1018  *
   1019  * Each glob is matched against the username in turn, and the first
   1020  * match found is used. If no match is found, the result is the
   1021  * argument `def'. If a match is found but without and explicit
   1022  * `yes'/`no', the result is the opposite of def.
   1023  *
   1024  * If the file doesn't exist at all, the result is the argument
   1025  * `nofile'
   1026  *
   1027  * Any line starting with `#' is considered a comment and ignored.
   1028  *
   1029  * Returns 0 if the user is denied, or 1 if they are allowed.
   1030  *
   1031  * NOTE: needs struct passwd *pw setup before use.
   1032  */
   1033 static int
   1034 checkuser(const char *fname, const char *name, int def, int nofile,
   1035 	    char **retclass)
   1036 {
   1037 	FILE	*fd;
   1038 	int	 retval;
   1039 	char	*word, *perm, *class, *buf, *p;
   1040 	size_t	 len, line;
   1041 
   1042 	retval = def;
   1043 	if (retclass != NULL)
   1044 		*retclass = NULL;
   1045 	if ((fd = fopen(conffilename(fname), "r")) == NULL)
   1046 		return nofile;
   1047 
   1048 	line = 0;
   1049 	for (;
   1050 	    (buf = fparseln(fd, &len, &line, NULL, FPARSELN_UNESCCOMM |
   1051 			    FPARSELN_UNESCCONT | FPARSELN_UNESCESC)) != NULL;
   1052 	    free(buf), buf = NULL) {
   1053 		word = perm = class = NULL;
   1054 		p = buf;
   1055 		if (len < 1)
   1056 			continue;
   1057 		if (p[len - 1] == '\n')
   1058 			p[--len] = '\0';
   1059 		if (EMPTYSTR(p))
   1060 			continue;
   1061 
   1062 		NEXTWORD(p, word);
   1063 		NEXTWORD(p, perm);
   1064 		NEXTWORD(p, class);
   1065 		if (EMPTYSTR(word))
   1066 			continue;
   1067 		if (!EMPTYSTR(class)) {
   1068 			if (strcasecmp(class, "all") == 0 ||
   1069 			    strcasecmp(class, "none") == 0) {
   1070 				syslog(LOG_WARNING,
   1071 		"%s line %d: illegal user-defined class `%s' - skipping entry",
   1072 					    fname, (int)line, class);
   1073 				continue;
   1074 			}
   1075 		}
   1076 
   1077 					/* have a host specifier */
   1078 		if ((p = strchr(word, '@')) != NULL) {
   1079 			unsigned long	net, mask, addr;
   1080 			int		bits;
   1081 
   1082 			*p++ = '\0';
   1083 					/* check against network or CIDR */
   1084 			if (isdigit((unsigned char)*p) &&
   1085 			    (bits = inet_net_pton(AF_INET, p,
   1086 			    &net, sizeof(net))) != -1) {
   1087 				net = ntohl(net);
   1088 				mask = 0xffffffffU << (32 - bits);
   1089 				addr = ntohl(his_addr.su_addr.s_addr);
   1090 				if ((addr & mask) != net)
   1091 					continue;
   1092 
   1093 					/* check against hostname glob */
   1094 			} else if (fnmatch(p, remotehost, FNM_CASEFOLD) != 0)
   1095 				continue;
   1096 		}
   1097 
   1098 					/* have a group specifier */
   1099 		if ((p = strchr(word, ':')) != NULL) {
   1100 			gid_t	*groups, *ng;
   1101 			int	 gsize, i, found;
   1102 
   1103 			if (pw == NULL)
   1104 				continue;	/* no match for unknown user */
   1105 			*p++ = '\0';
   1106 			groups = NULL;
   1107 			gsize = 16;
   1108 			do {
   1109 				ng = realloc(groups, gsize * sizeof(gid_t));
   1110 				if (ng == NULL)
   1111 					fatal(
   1112 					    "Local resource failure: realloc");
   1113 				groups = ng;
   1114 			} while (getgrouplist(pw->pw_name, pw->pw_gid,
   1115 						groups, &gsize) == -1);
   1116 			found = 0;
   1117 			for (i = 0; i < gsize; i++) {
   1118 				struct group *g;
   1119 
   1120 				if ((g = getgrgid(groups[i])) == NULL)
   1121 					continue;
   1122 				if (fnmatch(p, g->gr_name, 0) == 0) {
   1123 					found = 1;
   1124 					break;
   1125 				}
   1126 			}
   1127 			free(groups);
   1128 			if (!found)
   1129 				continue;
   1130 		}
   1131 
   1132 					/* check against username glob */
   1133 		if (fnmatch(word, name, 0) != 0)
   1134 			continue;
   1135 
   1136 		if (perm != NULL &&
   1137 		    ((strcasecmp(perm, "allow") == 0) ||
   1138 		     (strcasecmp(perm, "yes") == 0)))
   1139 			retval = 1;
   1140 		else if (perm != NULL &&
   1141 		    ((strcasecmp(perm, "deny") == 0) ||
   1142 		     (strcasecmp(perm, "no") == 0)))
   1143 			retval = 0;
   1144 		else
   1145 			retval = !def;
   1146 		if (!EMPTYSTR(class) && retclass != NULL)
   1147 			*retclass = ftpd_strdup(class);
   1148 		free(buf);
   1149 		break;
   1150 	}
   1151 	(void) fclose(fd);
   1152 	return (retval);
   1153 }
   1154 
   1155 /*
   1156  * Check if user is allowed by /etc/ftpusers
   1157  * returns 1 for yes, 0 for no
   1158  *
   1159  * NOTE: needs struct passwd *pw setup (for checkuser())
   1160  */
   1161 static int
   1162 checkaccess(const char *name)
   1163 {
   1164 
   1165 	return (checkuser(_NAME_FTPUSERS, name, 1, 0, NULL));
   1166 }
   1167 
   1168 static void
   1169 login_utmp(const char *line, const char *name, const char *host,
   1170     struct sockinet *haddr)
   1171 {
   1172 #if defined(SUPPORT_UTMPX) || defined(SUPPORT_UTMP)
   1173 	struct timeval tv;
   1174 	(void)gettimeofday(&tv, NULL);
   1175 #endif
   1176 #ifdef SUPPORT_UTMPX
   1177 	if (doutmp) {
   1178 		(void)memset(&utmpx, 0, sizeof(utmpx));
   1179 		utmpx.ut_tv = tv;
   1180 		utmpx.ut_pid = getpid();
   1181 		utmpx.ut_id[0] = 'f';
   1182 		utmpx.ut_id[1] = 't';
   1183 		utmpx.ut_id[2] = 'p';
   1184 		utmpx.ut_id[3] = '*';
   1185 		utmpx.ut_type = USER_PROCESS;
   1186 		(void)strncpy(utmpx.ut_name, name, sizeof(utmpx.ut_name));
   1187 		(void)strncpy(utmpx.ut_line, line, sizeof(utmpx.ut_line));
   1188 		(void)strncpy(utmpx.ut_host, host, sizeof(utmpx.ut_host));
   1189 		(void)memcpy(&utmpx.ut_ss, &haddr->si_su, haddr->su_len);
   1190 		ftpd_loginx(&utmpx);
   1191 	}
   1192 	if (dowtmp)
   1193 		ftpd_logwtmpx(line, name, host, haddr, 0, USER_PROCESS);
   1194 #endif
   1195 #ifdef SUPPORT_UTMP
   1196 	if (doutmp) {
   1197 		(void)memset(&utmp, 0, sizeof(utmp));
   1198 		(void)time(&utmp.ut_time);
   1199 		(void)strncpy(utmp.ut_name, name, sizeof(utmp.ut_name));
   1200 		(void)strncpy(utmp.ut_line, line, sizeof(utmp.ut_line));
   1201 		(void)strncpy(utmp.ut_host, host, sizeof(utmp.ut_host));
   1202 		ftpd_login(&utmp);
   1203 	}
   1204 	if (dowtmp)
   1205 		ftpd_logwtmp(line, name, host);
   1206 #endif
   1207 }
   1208 
   1209 static void
   1210 logout_utmp(void)
   1211 {
   1212 #ifdef SUPPORT_UTMPX
   1213 	int okwtmpx = dowtmp;
   1214 #endif
   1215 #ifdef SUPPORT_UTMP
   1216 	int okwtmp = dowtmp;
   1217 #endif
   1218 	if (logged_in) {
   1219 #ifdef SUPPORT_UTMPX
   1220 		if (doutmp)
   1221 			okwtmpx &= ftpd_logoutx(ttyline, 0, DEAD_PROCESS);
   1222 		if (okwtmpx)
   1223 			ftpd_logwtmpx(ttyline, "", "", NULL, 0, DEAD_PROCESS);
   1224 #endif
   1225 #ifdef SUPPORT_UTMP
   1226 		if (doutmp)
   1227 			okwtmp &= ftpd_logout(ttyline);
   1228 		if (okwtmp)
   1229 			ftpd_logwtmp(ttyline, "", "");
   1230 #endif
   1231 	}
   1232 }
   1233 
   1234 /*
   1235  * Terminate login as previous user (if any), resetting state;
   1236  * used when USER command is given or login fails.
   1237  */
   1238 static void
   1239 end_login(void)
   1240 {
   1241 #ifdef USE_PAM
   1242 	int e;
   1243 #endif
   1244 	logout_utmp();
   1245 	show_chdir_messages(-1);		/* flush chdir cache */
   1246 	if (pw != NULL && pw->pw_passwd != NULL)
   1247 		memset(pw->pw_passwd, 0, strlen(pw->pw_passwd));
   1248 	pw = NULL;
   1249 	logged_in = 0;
   1250 	askpasswd = 0;
   1251 	permitted = 0;
   1252 	quietmessages = 0;
   1253 	gidcount = 0;
   1254 	curclass.type = CLASS_REAL;
   1255 	(void) seteuid((uid_t)0);
   1256 #ifdef	LOGIN_CAP
   1257 	setusercontext(NULL, getpwuid(0), 0,
   1258 		       LOGIN_SETPRIORITY|LOGIN_SETRESOURCES|LOGIN_SETUMASK);
   1259 #endif
   1260 #ifdef USE_PAM
   1261 	if (pamh) {
   1262 		if ((e = pam_setcred(pamh, PAM_DELETE_CRED)) != PAM_SUCCESS)
   1263 			syslog(LOG_ERR, "pam_setcred: %s",
   1264 			    pam_strerror(pamh, e));
   1265 		if ((e = pam_close_session(pamh,0)) != PAM_SUCCESS)
   1266 			syslog(LOG_ERR, "pam_close_session: %s",
   1267 			    pam_strerror(pamh, e));
   1268 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS)
   1269 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
   1270 		pamh = NULL;
   1271 	}
   1272 #endif
   1273 }
   1274 
   1275 void
   1276 pass(const char *passwd)
   1277 {
   1278 	do_pass(0, 0, passwd);
   1279 }
   1280 
   1281 /*
   1282  * Perform the passwd confirmation and login.
   1283  *
   1284  * If pass_checked is zero, confirm passwd is correct, & ignore pass_rval.
   1285  * This is the traditional PASS implementation.
   1286  *
   1287  * If pass_checked is non-zero, use pass_rval and ignore passwd.
   1288  * This is used by auth_pam() which has already parsed PASS.
   1289  * This only applies to curclass.type != CLASS_GUEST.
   1290  */
   1291 static void
   1292 do_pass(int pass_checked, int pass_rval, const char *passwd)
   1293 {
   1294 	int		 rval;
   1295 	char		 root[MAXPATHLEN];
   1296 #ifdef	LOGIN_CAP
   1297 	login_cap_t *lc = NULL;
   1298 #endif
   1299 #ifdef USE_PAM
   1300 	int e;
   1301 #endif
   1302 
   1303 	rval = 1;
   1304 
   1305 	if (logged_in || askpasswd == 0) {
   1306 		reply(503, "Login with USER first.");
   1307 		return;
   1308 	}
   1309 	askpasswd = 0;
   1310 	if (curclass.type != CLASS_GUEST) {
   1311 			/* "ftp" is the only account allowed with no password */
   1312 		if (pw == NULL) {
   1313 			rval = 1;	/* failure below */
   1314 			goto skip;
   1315 		}
   1316 		if (pass_checked) {	/* password validated in user() */
   1317 			rval = pass_rval;
   1318 			goto skip;
   1319 		}
   1320 #ifdef USE_PAM
   1321 		syslog(LOG_ERR, "do_pass: USE_PAM shouldn't get here");
   1322 		rval = 1;
   1323 		goto skip;
   1324 #endif
   1325 #if defined(KERBEROS)
   1326 		if (klogin(pw, "", hostname, (char *)passwd) == 0) {
   1327 			rval = 0;
   1328 			goto skip;
   1329 		}
   1330 #endif
   1331 #if defined(KERBEROS5)
   1332 		if (k5login(pw, "", hostname, (char *)passwd) == 0) {
   1333 			rval = 0;
   1334 			goto skip;
   1335 		}
   1336 #endif
   1337 #ifdef SKEY
   1338 		if (skey_haskey(pw->pw_name) == 0) {
   1339 			char *p;
   1340 			int r;
   1341 
   1342 			p = ftpd_strdup(passwd);
   1343 			r = skey_passcheck(pw->pw_name, p);
   1344 			free(p);
   1345 			if (r != -1) {
   1346 				rval = 0;
   1347 				goto skip;
   1348 			}
   1349 		}
   1350 #endif
   1351 		if (!sflag)
   1352 			rval = checkpassword(pw, passwd);
   1353 		else
   1354 			rval = 1;
   1355 
   1356  skip:
   1357 
   1358 			/*
   1359 			 * If rval > 0, the user failed the authentication check
   1360 			 * above.  If rval == 0, either Kerberos or local
   1361 			 * authentication succeeded.
   1362 			 */
   1363 		if (rval) {
   1364 			reply(530, "%s", rval == 2 ? "Password expired." :
   1365 			    "Login incorrect.");
   1366 			if (logging) {
   1367 				syslog(LOG_NOTICE,
   1368 				    "FTP LOGIN FAILED FROM %s", remotehost);
   1369 				syslog(LOG_AUTHPRIV | LOG_NOTICE,
   1370 				    "FTP LOGIN FAILED FROM %s, %s",
   1371 				    remotehost, curname);
   1372 			}
   1373 			pw = NULL;
   1374 			if (login_attempts++ >= 5) {
   1375 				syslog(LOG_NOTICE,
   1376 				    "repeated login failures from %s",
   1377 				    remotehost);
   1378 				exit(0);
   1379 			}
   1380 			return;
   1381 		}
   1382 	}
   1383 
   1384 			/* password ok; check if anything else prevents login */
   1385 	if (! permitted) {
   1386 		reply(530, "User %s may not use FTP.", pw->pw_name);
   1387 		if (logging)
   1388 			syslog(LOG_NOTICE, "FTP LOGIN REFUSED FROM %s, %s",
   1389 			    remotehost, pw->pw_name);
   1390 		goto bad;
   1391 	}
   1392 
   1393 	login_attempts = 0;		/* this time successful */
   1394 	if (setegid((gid_t)pw->pw_gid) < 0) {
   1395 		reply(550, "Can't set gid.");
   1396 		goto bad;
   1397 	}
   1398 #ifdef	LOGIN_CAP
   1399 	if ((lc = login_getpwclass(pw)) != NULL) {
   1400 #ifdef notyet
   1401 		char	remote_ip[NI_MAXHOST];
   1402 
   1403 		if (getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len,
   1404 			remote_ip, sizeof(remote_ip) - 1, NULL, 0,
   1405 			NI_NUMERICHOST))
   1406 				*remote_ip = 0;
   1407 		remote_ip[sizeof(remote_ip) - 1] = 0;
   1408 		if (!auth_hostok(lc, remotehost, remote_ip)) {
   1409 			syslog(LOG_INFO|LOG_AUTH,
   1410 			    "FTP LOGIN FAILED (HOST) as %s: permission denied.",
   1411 			    pw->pw_name);
   1412 			reply(530, "Permission denied.");
   1413 			pw = NULL;
   1414 			return;
   1415 		}
   1416 		if (!auth_timeok(lc, time(NULL))) {
   1417 			reply(530, "Login not available right now.");
   1418 			pw = NULL;
   1419 			return;
   1420 		}
   1421 #endif
   1422 	}
   1423 	setsid();
   1424 	setusercontext(lc, pw, 0,
   1425 		LOGIN_SETLOGIN|LOGIN_SETGROUP|LOGIN_SETPRIORITY|
   1426 		LOGIN_SETRESOURCES|LOGIN_SETUMASK);
   1427 #else
   1428 	(void) initgroups(pw->pw_name, pw->pw_gid);
   1429 			/* cache groups for cmds.c::matchgroup() */
   1430 #endif
   1431 #ifdef USE_PAM
   1432 	if (pamh) {
   1433 		if ((e = pam_open_session(pamh, 0)) != PAM_SUCCESS) {
   1434 			syslog(LOG_ERR, "pam_open_session: %s",
   1435 			    pam_strerror(pamh, e));
   1436 		} else if ((e = pam_setcred(pamh, PAM_ESTABLISH_CRED))
   1437 		    != PAM_SUCCESS) {
   1438 			syslog(LOG_ERR, "pam_setcred: %s",
   1439 			    pam_strerror(pamh, e));
   1440 		}
   1441 	}
   1442 #endif
   1443 	gidcount = getgroups(0, NULL);
   1444 	if (gidlist)
   1445 		free(gidlist);
   1446 	gidlist = malloc(gidcount * sizeof *gidlist);
   1447 	gidcount = getgroups(gidcount, gidlist);
   1448 
   1449 	/* open utmp/wtmp before chroot */
   1450 	login_utmp(ttyline, pw->pw_name, remotehost, &his_addr);
   1451 
   1452 	logged_in = 1;
   1453 
   1454 	connections = 1;
   1455 	if (dopidfile)
   1456 		count_users();
   1457 	if (curclass.limit != -1 && connections > curclass.limit) {
   1458 		if (! EMPTYSTR(curclass.limitfile))
   1459 			(void)display_file(conffilename(curclass.limitfile),
   1460 			    530);
   1461 		reply(530,
   1462 		    "User %s access denied, connection limit of " LLF
   1463 		    " reached.",
   1464 		    pw->pw_name, (LLT)curclass.limit);
   1465 		syslog(LOG_NOTICE,
   1466 		    "Maximum connection limit of " LLF
   1467 		    " for class %s reached, login refused for %s",
   1468 		    (LLT)curclass.limit, curclass.classname, pw->pw_name);
   1469 		goto bad;
   1470 	}
   1471 
   1472 	homedir[0] = '/';
   1473 	switch (curclass.type) {
   1474 	case CLASS_GUEST:
   1475 			/*
   1476 			 * We MUST do a chdir() after the chroot. Otherwise
   1477 			 * the old current directory will be accessible as "."
   1478 			 * outside the new root!
   1479 			 */
   1480 		format_path(root,
   1481 		    curclass.chroot ? curclass.chroot :
   1482 		    anondir ? anondir :
   1483 		    pw->pw_dir);
   1484 		format_path(homedir,
   1485 		    curclass.homedir ? curclass.homedir :
   1486 		    "/");
   1487 		if (EMPTYSTR(homedir))
   1488 			homedir[0] = '/';
   1489 		if (EMPTYSTR(root) || chroot(root) < 0) {
   1490 			syslog(LOG_NOTICE,
   1491 			    "GUEST user %s: can't chroot to %s: %m",
   1492 			    pw->pw_name, root);
   1493 			goto bad_guest;
   1494 		}
   1495 		if (chdir(homedir) < 0) {
   1496 			syslog(LOG_NOTICE,
   1497 			    "GUEST user %s: can't chdir to %s: %m",
   1498 			    pw->pw_name, homedir);
   1499  bad_guest:
   1500 			reply(550, "Can't set guest privileges.");
   1501 			goto bad;
   1502 		}
   1503 		break;
   1504 	case CLASS_CHROOT:
   1505 		format_path(root,
   1506 		    curclass.chroot ? curclass.chroot :
   1507 		    pw->pw_dir);
   1508 		format_path(homedir,
   1509 		    curclass.homedir ? curclass.homedir :
   1510 		    "/");
   1511 		if (EMPTYSTR(homedir))
   1512 			homedir[0] = '/';
   1513 		if (EMPTYSTR(root) || chroot(root) < 0) {
   1514 			syslog(LOG_NOTICE,
   1515 			    "CHROOT user %s: can't chroot to %s: %m",
   1516 			    pw->pw_name, root);
   1517 			goto bad_chroot;
   1518 		}
   1519 		if (chdir(homedir) < 0) {
   1520 			syslog(LOG_NOTICE,
   1521 			    "CHROOT user %s: can't chdir to %s: %m",
   1522 			    pw->pw_name, homedir);
   1523  bad_chroot:
   1524 			reply(550, "Can't change root.");
   1525 			goto bad;
   1526 		}
   1527 		break;
   1528 	case CLASS_REAL:
   1529 			/* only chroot REAL if explicitly requested */
   1530 		if (! EMPTYSTR(curclass.chroot)) {
   1531 			format_path(root, curclass.chroot);
   1532 			if (EMPTYSTR(root) || chroot(root) < 0) {
   1533 				syslog(LOG_NOTICE,
   1534 				    "REAL user %s: can't chroot to %s: %m",
   1535 				    pw->pw_name, root);
   1536 				goto bad_chroot;
   1537 			}
   1538 		}
   1539 		format_path(homedir,
   1540 		    curclass.homedir ? curclass.homedir :
   1541 		    pw->pw_dir);
   1542 		if (EMPTYSTR(homedir) || chdir(homedir) < 0) {
   1543 			if (chdir("/") < 0) {
   1544 				syslog(LOG_NOTICE,
   1545 				    "REAL user %s: can't chdir to %s: %m",
   1546 				    pw->pw_name,
   1547 				    !EMPTYSTR(homedir) ?  homedir : "/");
   1548 				reply(530,
   1549 				    "User %s: can't change directory to %s.",
   1550 				    pw->pw_name,
   1551 				    !EMPTYSTR(homedir) ? homedir : "/");
   1552 				goto bad;
   1553 			} else {
   1554 				reply(-230,
   1555 				    "No directory! Logging in with home=/");
   1556 				homedir[0] = '/';
   1557 			}
   1558 		}
   1559 		break;
   1560 	}
   1561 #ifndef LOGIN_CAP
   1562 	setsid();
   1563 	setlogin(pw->pw_name);
   1564 #endif
   1565 	if (dropprivs ||
   1566 	    (curclass.type != CLASS_REAL &&
   1567 	    ntohs(ctrl_addr.su_port) > IPPORT_RESERVED + 1)) {
   1568 		dropprivs++;
   1569 		if (setgid((gid_t)pw->pw_gid) < 0) {
   1570 			reply(550, "Can't set gid.");
   1571 			goto bad;
   1572 		}
   1573 		if (setuid((uid_t)pw->pw_uid) < 0) {
   1574 			reply(550, "Can't set uid.");
   1575 			goto bad;
   1576 		}
   1577 	} else {
   1578 		if (seteuid((uid_t)pw->pw_uid) < 0) {
   1579 			reply(550, "Can't set uid.");
   1580 			goto bad;
   1581 		}
   1582 	}
   1583 	setenv("HOME", homedir, 1);
   1584 
   1585 	if (curclass.type == CLASS_GUEST && passwd[0] == '-')
   1586 		quietmessages = 1;
   1587 
   1588 			/*
   1589 			 * Display a login message, if it exists.
   1590 			 * N.B. reply(230,) must follow the message.
   1591 			 */
   1592 	if (! EMPTYSTR(curclass.motd))
   1593 		(void)display_file(conffilename(curclass.motd), 230);
   1594 	show_chdir_messages(230);
   1595 	if (curclass.type == CLASS_GUEST) {
   1596 		char *p;
   1597 
   1598 		reply(230, "Guest login ok, access restrictions apply.");
   1599 #if defined(HAVE_SETPROCTITLE)
   1600 		snprintf(proctitle, sizeof(proctitle),
   1601 		    "%s: anonymous/%s", remotehost, passwd);
   1602 		setproctitle("%s", proctitle);
   1603 #endif /* defined(HAVE_SETPROCTITLE) */
   1604 		if (logging)
   1605 			syslog(LOG_INFO,
   1606 			"ANONYMOUS FTP LOGIN FROM %s, %s (class: %s, type: %s)",
   1607 			    remotehost, passwd,
   1608 			    curclass.classname, CURCLASSTYPE);
   1609 			/* store guest password reply into pw_passwd */
   1610 		REASSIGN(pw->pw_passwd, ftpd_strdup(passwd));
   1611 		for (p = pw->pw_passwd; *p; p++)
   1612 			if (!isgraph((unsigned char)*p))
   1613 				*p = '_';
   1614 	} else {
   1615 		reply(230, "User %s logged in.", pw->pw_name);
   1616 #if defined(HAVE_SETPROCTITLE)
   1617 		snprintf(proctitle, sizeof(proctitle),
   1618 		    "%s: %s", remotehost, pw->pw_name);
   1619 		setproctitle("%s", proctitle);
   1620 #endif /* defined(HAVE_SETPROCTITLE) */
   1621 		if (logging)
   1622 			syslog(LOG_INFO,
   1623 			    "FTP LOGIN FROM %s as %s (class: %s, type: %s)",
   1624 			    remotehost, pw->pw_name,
   1625 			    curclass.classname, CURCLASSTYPE);
   1626 	}
   1627 	(void) umask(curclass.umask);
   1628 #ifdef	LOGIN_CAP
   1629 	login_close(lc);
   1630 #endif
   1631 	return;
   1632 
   1633  bad:
   1634 #ifdef	LOGIN_CAP
   1635 	login_close(lc);
   1636 #endif
   1637 			/* Forget all about it... */
   1638 	end_login();
   1639 }
   1640 
   1641 void
   1642 retrieve(char *argv[], const char *name)
   1643 {
   1644 	FILE *fin, *dout;
   1645 	struct stat st;
   1646 	int (*closefunc)(FILE *) = NULL;
   1647 	int dolog, sendrv, closerv, stderrfd, isconversion, isdata, isls;
   1648 	struct timeval start, finish, td, *tdp;
   1649 	struct rusage rusage_before, rusage_after;
   1650 	const char *dispname;
   1651 	char *error;
   1652 
   1653 	sendrv = closerv = stderrfd = -1;
   1654 	isconversion = isdata = isls = dolog = 0;
   1655 	tdp = NULL;
   1656 	dispname = name;
   1657 	fin = dout = NULL;
   1658 	error = NULL;
   1659 	if (argv == NULL) {		/* if not running a command ... */
   1660 		dolog = 1;
   1661 		isdata = 1;
   1662 		fin = fopen(name, "r");
   1663 		closefunc = fclose;
   1664 		if (fin == NULL)	/* doesn't exist?; try a conversion */
   1665 			argv = do_conversion(name);
   1666 		if (argv != NULL) {
   1667 			isconversion++;
   1668 			syslog(LOG_DEBUG, "get command: '%s' on '%s'",
   1669 			    argv[0], name);
   1670 		}
   1671 	}
   1672 	if (argv != NULL) {
   1673 		char temp[MAXPATHLEN];
   1674 
   1675 		if (strcmp(argv[0], INTERNAL_LS) == 0) {
   1676 			isls = 1;
   1677 			stderrfd = -1;
   1678 		} else {
   1679 			(void)snprintf(temp, sizeof(temp), "%s", TMPFILE);
   1680 			stderrfd = mkstemp(temp);
   1681 			if (stderrfd != -1)
   1682 				(void)unlink(temp);
   1683 		}
   1684 		dispname = argv[0];
   1685 		fin = ftpd_popen(argv, "r", stderrfd);
   1686 		closefunc = ftpd_pclose;
   1687 		st.st_size = -1;
   1688 		st.st_blksize = BUFSIZ;
   1689 	}
   1690 	if (fin == NULL) {
   1691 		if (errno != 0) {
   1692 			perror_reply(550, dispname);
   1693 			if (dolog)
   1694 				logxfer("get", -1, name, NULL, NULL,
   1695 				    strerror(errno));
   1696 		}
   1697 		goto cleanupretrieve;
   1698 	}
   1699 	byte_count = -1;
   1700 	if (argv == NULL
   1701 	    && (fstat(fileno(fin), &st) < 0 || !S_ISREG(st.st_mode))) {
   1702 		error = "Not a plain file";
   1703 		reply(550, "%s: %s.", dispname, error);
   1704 		goto done;
   1705 	}
   1706 	if (restart_point) {
   1707 		if (type == TYPE_A) {
   1708 			off_t i;
   1709 			int c;
   1710 
   1711 			for (i = 0; i < restart_point; i++) {
   1712 				if ((c=getc(fin)) == EOF) {
   1713 					error = strerror(errno);
   1714 					perror_reply(550, dispname);
   1715 					goto done;
   1716 				}
   1717 				if (c == '\n')
   1718 					i++;
   1719 			}
   1720 		} else if (lseek(fileno(fin), restart_point, SEEK_SET) < 0) {
   1721 			error = strerror(errno);
   1722 			perror_reply(550, dispname);
   1723 			goto done;
   1724 		}
   1725 	}
   1726 	dout = dataconn(dispname, st.st_size, "w");
   1727 	if (dout == NULL)
   1728 		goto done;
   1729 
   1730 	(void)getrusage(RUSAGE_SELF, &rusage_before);
   1731 	(void)gettimeofday(&start, NULL);
   1732 	sendrv = send_data(fin, dout, &st, isdata);
   1733 	(void)gettimeofday(&finish, NULL);
   1734 	(void)getrusage(RUSAGE_SELF, &rusage_after);
   1735 	closedataconn(dout);		/* close now to affect timing stats */
   1736 	timersub(&finish, &start, &td);
   1737 	tdp = &td;
   1738  done:
   1739 	if (dolog) {
   1740 		logxfer("get", byte_count, name, NULL, tdp, error);
   1741 		if (tdp != NULL)
   1742 			logrusage(&rusage_before, &rusage_after);
   1743 	}
   1744 	closerv = (*closefunc)(fin);
   1745 	if (sendrv == 0) {
   1746 		FILE *errf;
   1747 		struct stat sb;
   1748 
   1749 		if (!isls && argv != NULL && closerv != 0) {
   1750 			reply(-226,
   1751 			    "Command returned an exit status of %d",
   1752 			    closerv);
   1753 			if (isconversion)
   1754 				syslog(LOG_WARNING,
   1755 				    "retrieve command: '%s' returned %d",
   1756 				    argv[0], closerv);
   1757 		}
   1758 		if (!isls && argv != NULL && stderrfd != -1 &&
   1759 		    (fstat(stderrfd, &sb) == 0) && sb.st_size > 0 &&
   1760 		    ((errf = fdopen(stderrfd, "r")) != NULL)) {
   1761 			char *cp, line[LINE_MAX];
   1762 
   1763 			reply(-226, "Command error messages:");
   1764 			rewind(errf);
   1765 			while (fgets(line, sizeof(line), errf) != NULL) {
   1766 				if ((cp = strchr(line, '\n')) != NULL)
   1767 					*cp = '\0';
   1768 				reply(0, "  %s", line);
   1769 			}
   1770 			(void) fflush(stdout);
   1771 			(void) fclose(errf);
   1772 				/* a reply(226,) must follow */
   1773 		}
   1774 		reply(226, "Transfer complete.");
   1775 	}
   1776  cleanupretrieve:
   1777 	if (stderrfd != -1)
   1778 		(void)close(stderrfd);
   1779 	if (isconversion)
   1780 		free(argv);
   1781 }
   1782 
   1783 void
   1784 store(const char *name, const char *fmode, int unique)
   1785 {
   1786 	FILE *fout, *din;
   1787 	struct stat st;
   1788 	int (*closefunc)(FILE *);
   1789 	struct timeval start, finish, td, *tdp;
   1790 	char *desc, *error;
   1791 
   1792 	din = NULL;
   1793 	desc = (*fmode == 'w') ? "put" : "append";
   1794 	error = NULL;
   1795 	if (unique && stat(name, &st) == 0 &&
   1796 	    (name = gunique(name)) == NULL) {
   1797 		logxfer(desc, -1, name, NULL, NULL,
   1798 		    "cannot create unique file");
   1799 		goto cleanupstore;
   1800 	}
   1801 
   1802 	if (restart_point)
   1803 		fmode = "r+";
   1804 	fout = fopen(name, fmode);
   1805 	closefunc = fclose;
   1806 	tdp = NULL;
   1807 	if (fout == NULL) {
   1808 		perror_reply(553, name);
   1809 		logxfer(desc, -1, name, NULL, NULL, strerror(errno));
   1810 		goto cleanupstore;
   1811 	}
   1812 	byte_count = -1;
   1813 	if (restart_point) {
   1814 		if (type == TYPE_A) {
   1815 			off_t i;
   1816 			int c;
   1817 
   1818 			for (i = 0; i < restart_point; i++) {
   1819 				if ((c=getc(fout)) == EOF) {
   1820 					error = strerror(errno);
   1821 					perror_reply(550, name);
   1822 					goto done;
   1823 				}
   1824 				if (c == '\n')
   1825 					i++;
   1826 			}
   1827 			/*
   1828 			 * We must do this seek to "current" position
   1829 			 * because we are changing from reading to
   1830 			 * writing.
   1831 			 */
   1832 			if (fseek(fout, 0L, SEEK_CUR) < 0) {
   1833 				error = strerror(errno);
   1834 				perror_reply(550, name);
   1835 				goto done;
   1836 			}
   1837 		} else if (lseek(fileno(fout), restart_point, SEEK_SET) < 0) {
   1838 			error = strerror(errno);
   1839 			perror_reply(550, name);
   1840 			goto done;
   1841 		}
   1842 	}
   1843 	din = dataconn(name, (off_t)-1, "r");
   1844 	if (din == NULL)
   1845 		goto done;
   1846 	(void)gettimeofday(&start, NULL);
   1847 	if (receive_data(din, fout) == 0) {
   1848 		if (unique)
   1849 			reply(226, "Transfer complete (unique file name:%s).",
   1850 			    name);
   1851 		else
   1852 			reply(226, "Transfer complete.");
   1853 	}
   1854 	(void)gettimeofday(&finish, NULL);
   1855 	closedataconn(din);		/* close now to affect timing stats */
   1856 	timersub(&finish, &start, &td);
   1857 	tdp = &td;
   1858  done:
   1859 	logxfer(desc, byte_count, name, NULL, tdp, error);
   1860 	(*closefunc)(fout);
   1861  cleanupstore:
   1862 	;
   1863 }
   1864 
   1865 static FILE *
   1866 getdatasock(const char *fmode)
   1867 {
   1868 	int		on, s, t, tries;
   1869 	in_port_t	port;
   1870 
   1871 	on = 1;
   1872 	if (data >= 0)
   1873 		return (fdopen(data, fmode));
   1874 	if (! dropprivs)
   1875 		(void) seteuid((uid_t)0);
   1876 	s = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
   1877 	if (s < 0)
   1878 		goto bad;
   1879 	if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR,
   1880 	    (char *) &on, sizeof(on)) < 0)
   1881 		goto bad;
   1882 	if (setsockopt(s, SOL_SOCKET, SO_KEEPALIVE,
   1883 	    (char *) &on, sizeof(on)) < 0)
   1884 		goto bad;
   1885 			/* anchor socket to avoid multi-homing problems */
   1886 	data_source = ctrl_addr;
   1887 			/*
   1888 			 * By default source port for PORT connctions is
   1889 			 * ctrlport-1 (see RFC959 section 5.2).
   1890 			 * However, if privs have been dropped and that
   1891 			 * would be < IPPORT_RESERVED, use a random port
   1892 			 * instead.
   1893 			 */
   1894 	if (dataport)
   1895 		port = dataport;
   1896 	else
   1897 		port = ntohs(ctrl_addr.su_port) - 1;
   1898 	if (dropprivs && port < IPPORT_RESERVED)
   1899 		port = 0;		/* use random port */
   1900 	data_source.su_port = htons(port);
   1901 
   1902 	for (tries = 1; ; tries++) {
   1903 		if (bind(s, (struct sockaddr *)&data_source.si_su,
   1904 		    data_source.su_len) >= 0)
   1905 			break;
   1906 		if (errno != EADDRINUSE || tries > 10)
   1907 			goto bad;
   1908 		sleep(tries);
   1909 	}
   1910 	if (! dropprivs)
   1911 		(void) seteuid((uid_t)pw->pw_uid);
   1912 #ifdef IP_TOS
   1913 	if (!mapped && ctrl_addr.su_family == AF_INET) {
   1914 		on = IPTOS_THROUGHPUT;
   1915 		if (setsockopt(s, IPPROTO_IP, IP_TOS, (char *)&on,
   1916 			       sizeof(int)) < 0)
   1917 			syslog(LOG_WARNING, "setsockopt (IP_TOS): %m");
   1918 	}
   1919 #endif
   1920 	return (fdopen(s, fmode));
   1921  bad:
   1922 		/* Return the real value of errno (close may change it) */
   1923 	t = errno;
   1924 	if (! dropprivs)
   1925 		(void) seteuid((uid_t)pw->pw_uid);
   1926 	(void) close(s);
   1927 	errno = t;
   1928 	return (NULL);
   1929 }
   1930 
   1931 FILE *
   1932 dataconn(const char *name, off_t size, const char *fmode)
   1933 {
   1934 	char sizebuf[32];
   1935 	FILE *file;
   1936 	int retry, tos, keepalive, conerrno;
   1937 
   1938 	file_size = size;
   1939 	byte_count = 0;
   1940 	if (size != (off_t) -1)
   1941 		(void)snprintf(sizebuf, sizeof(sizebuf), " (" LLF " byte%s)",
   1942 		    (LLT)size, PLURAL(size));
   1943 	else
   1944 		sizebuf[0] = '\0';
   1945 	if (pdata >= 0) {
   1946 		struct sockinet from;
   1947 		int s;
   1948 		socklen_t fromlen = sizeof(from.su_len);
   1949 
   1950 		(void) alarm(curclass.timeout);
   1951 		s = accept(pdata, (struct sockaddr *)&from.si_su, &fromlen);
   1952 		(void) alarm(0);
   1953 		if (s < 0) {
   1954 			reply(425, "Can't open data connection.");
   1955 			(void) close(pdata);
   1956 			pdata = -1;
   1957 			return (NULL);
   1958 		}
   1959 		(void) close(pdata);
   1960 		pdata = s;
   1961 		switch (from.su_family) {
   1962 		case AF_INET:
   1963 #ifdef IP_TOS
   1964 			if (!mapped) {
   1965 				tos = IPTOS_THROUGHPUT;
   1966 				(void) setsockopt(s, IPPROTO_IP, IP_TOS,
   1967 				    (char *)&tos, sizeof(int));
   1968 			}
   1969 			break;
   1970 #endif
   1971 		}
   1972 		/* Set keepalives on the socket to detect dropped conns. */
   1973 #ifdef SO_KEEPALIVE
   1974 		keepalive = 1;
   1975 		(void) setsockopt(s, SOL_SOCKET, SO_KEEPALIVE,
   1976 		    (char *)&keepalive, sizeof(int));
   1977 #endif
   1978 		reply(150, "Opening %s mode data connection for '%s'%s.",
   1979 		     type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
   1980 		return (fdopen(pdata, fmode));
   1981 	}
   1982 	if (data >= 0) {
   1983 		reply(125, "Using existing data connection for '%s'%s.",
   1984 		    name, sizebuf);
   1985 		usedefault = 1;
   1986 		return (fdopen(data, fmode));
   1987 	}
   1988 	if (usedefault)
   1989 		data_dest = his_addr;
   1990 	usedefault = 1;
   1991 	retry = conerrno = 0;
   1992 	do {
   1993 		file = getdatasock(fmode);
   1994 		if (file == NULL) {
   1995 			char hbuf[NI_MAXHOST];
   1996 			char pbuf[NI_MAXSERV];
   1997 
   1998 			if (getnameinfo((struct sockaddr *)&data_source.si_su,
   1999 			    data_source.su_len, hbuf, sizeof(hbuf), pbuf,
   2000 			    sizeof(pbuf), NI_NUMERICHOST | NI_NUMERICSERV))
   2001 				strlcpy(hbuf, "?", sizeof(hbuf));
   2002 			reply(425, "Can't create data socket (%s,%s): %s.",
   2003 			      hbuf, pbuf, strerror(errno));
   2004 			return (NULL);
   2005 		}
   2006 		data = fileno(file);
   2007 		conerrno = 0;
   2008 		if (connect(data, (struct sockaddr *)&data_dest.si_su,
   2009 		    data_dest.su_len) == 0)
   2010 			break;
   2011 		conerrno = errno;
   2012 		(void) fclose(file);
   2013 		file = NULL;
   2014 		data = -1;
   2015 		if (conerrno == EADDRINUSE) {
   2016 			sleep((unsigned) swaitint);
   2017 			retry += swaitint;
   2018 		} else {
   2019 			break;
   2020 		}
   2021 	} while (retry <= swaitmax);
   2022 	if (conerrno != 0) {
   2023 		perror_reply(425, "Can't build data connection");
   2024 		return (NULL);
   2025 	}
   2026 	reply(150, "Opening %s mode data connection for '%s'%s.",
   2027 	     type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf);
   2028 	return (file);
   2029 }
   2030 
   2031 void
   2032 closedataconn(FILE *fd)
   2033 {
   2034 
   2035 	if (fd == NULL)
   2036 		return;
   2037 	(void)fclose(fd);
   2038 	data = -1;
   2039 	if (pdata >= 0)
   2040 		(void)close(pdata);
   2041 	pdata = -1;
   2042 }
   2043 
   2044 int
   2045 write_data(int fd, char *buf, size_t size, off_t *bufrem,
   2046     struct timeval *then, int isdata)
   2047 {
   2048 	struct timeval now, td;
   2049 	ssize_t c;
   2050 
   2051 	while (size > 0) {
   2052 		c = size;
   2053 		if (curclass.writesize) {
   2054 			if (curclass.writesize < c)
   2055 				c = curclass.writesize;
   2056 		}
   2057 		if (curclass.rateget) {
   2058 			if (*bufrem < c)
   2059 				c = *bufrem;
   2060 		}
   2061 		(void) alarm(curclass.timeout);
   2062 		c = write(fd, buf, c);
   2063 		if (c <= 0)
   2064 			return (1);
   2065 		buf += c;
   2066 		size -= c;
   2067 		byte_count += c;
   2068 		if (isdata) {
   2069 			total_data_out += c;
   2070 			total_data += c;
   2071 		}
   2072 		total_bytes_out += c;
   2073 		total_bytes += c;
   2074 		if (curclass.rateget) {
   2075 			*bufrem -= c;
   2076 			if (*bufrem == 0) {
   2077 				(void)gettimeofday(&now, NULL);
   2078 				timersub(&now, then, &td);
   2079 				if (td.tv_sec == 0) {
   2080 					usleep(1000000 - td.tv_usec);
   2081 					(void)gettimeofday(then, NULL);
   2082 				} else
   2083 					*then = now;
   2084 				*bufrem = curclass.rateget;
   2085 			}
   2086 		}
   2087 	}
   2088 	return (0);
   2089 }
   2090 
   2091 static enum send_status
   2092 send_data_with_read(int filefd, int netfd, const struct stat *st, int isdata)
   2093 {
   2094 	struct timeval then;
   2095 	off_t bufrem;
   2096 	size_t readsize;
   2097 	char *buf;
   2098 	int c, error;
   2099 
   2100 	if (curclass.readsize)
   2101 		readsize = curclass.readsize;
   2102 	else
   2103 		readsize = (size_t)st->st_blksize;
   2104 	if ((buf = malloc(readsize)) == NULL) {
   2105 		perror_reply(451, "Local resource failure: malloc");
   2106 		return (SS_NO_TRANSFER);
   2107 	}
   2108 
   2109 	if (curclass.rateget) {
   2110 		bufrem = curclass.rateget;
   2111 		(void)gettimeofday(&then, NULL);
   2112 	}
   2113 	while (1) {
   2114 		(void) alarm(curclass.timeout);
   2115 		c = read(filefd, buf, readsize);
   2116 		if (c == 0)
   2117 			error = SS_SUCCESS;
   2118 		else if (c < 0)
   2119 			error = SS_FILE_ERROR;
   2120 		else if (write_data(netfd, buf, c, &bufrem, &then, isdata))
   2121 			error = SS_DATA_ERROR;
   2122 		else if (urgflag && handleoobcmd())
   2123 			error = SS_ABORTED;
   2124 		else
   2125 			continue;
   2126 
   2127 		free(buf);
   2128 		return (error);
   2129 	}
   2130 }
   2131 
   2132 static enum send_status
   2133 send_data_with_mmap(int filefd, int netfd, const struct stat *st, int isdata)
   2134 {
   2135 	struct timeval then;
   2136 	off_t bufrem, filesize, off, origoff;
   2137 	size_t mapsize, winsize;
   2138 	int error, sendbufsize, sendlowat;
   2139 	void *win;
   2140 
   2141 	if (curclass.sendbufsize) {
   2142 		sendbufsize = curclass.sendbufsize;
   2143 		if (setsockopt(netfd, SOL_SOCKET, SO_SNDBUF,
   2144 		    &sendbufsize, sizeof(int)) == -1)
   2145 			syslog(LOG_WARNING, "setsockopt(SO_SNDBUF, %d): %m",
   2146 			    sendbufsize);
   2147 	}
   2148 
   2149 	if (curclass.sendlowat) {
   2150 		sendlowat = curclass.sendlowat;
   2151 		if (setsockopt(netfd, SOL_SOCKET, SO_SNDLOWAT,
   2152 		    &sendlowat, sizeof(int)) == -1)
   2153 			syslog(LOG_WARNING, "setsockopt(SO_SNDLOWAT, %d): %m",
   2154 			    sendlowat);
   2155 	}
   2156 
   2157 	winsize = curclass.mmapsize;
   2158 	filesize = st->st_size;
   2159 	if (ftpd_debug)
   2160 		syslog(LOG_INFO, "mmapsize = %ld, writesize = %ld",
   2161 		    (long)winsize, (long)curclass.writesize);
   2162 	if (winsize == 0)
   2163 		goto try_read;
   2164 
   2165 	off = lseek(filefd, (off_t)0, SEEK_CUR);
   2166 	if (off == -1)
   2167 		goto try_read;
   2168 
   2169 	origoff = off;
   2170 	if (curclass.rateget) {
   2171 		bufrem = curclass.rateget;
   2172 		(void)gettimeofday(&then, NULL);
   2173 	}
   2174 	while (1) {
   2175 		mapsize = MIN(filesize - off, winsize);
   2176 		if (mapsize == 0)
   2177 			break;
   2178 		win = mmap(NULL, mapsize, PROT_READ,
   2179 		    MAP_FILE|MAP_SHARED, filefd, off);
   2180 		if (win == MAP_FAILED) {
   2181 			if (off == origoff)
   2182 				goto try_read;
   2183 			return (SS_FILE_ERROR);
   2184 		}
   2185 		(void) madvise(win, mapsize, MADV_SEQUENTIAL);
   2186 		error = write_data(netfd, win, mapsize, &bufrem, &then,
   2187 		    isdata);
   2188 		(void) madvise(win, mapsize, MADV_DONTNEED);
   2189 		munmap(win, mapsize);
   2190 		if (urgflag && handleoobcmd())
   2191 			return (SS_ABORTED);
   2192 		if (error)
   2193 			return (SS_DATA_ERROR);
   2194 		off += mapsize;
   2195 	}
   2196 	return (SS_SUCCESS);
   2197 
   2198  try_read:
   2199 	return (send_data_with_read(filefd, netfd, st, isdata));
   2200 }
   2201 
   2202 /*
   2203  * Transfer the contents of "instr" to "outstr" peer using the appropriate
   2204  * encapsulation of the data subject to Mode, Structure, and Type.
   2205  *
   2206  * NB: Form isn't handled.
   2207  */
   2208 static int
   2209 send_data(FILE *instr, FILE *outstr, const struct stat *st, int isdata)
   2210 {
   2211 	int	 c, filefd, netfd, rval;
   2212 
   2213 	urgflag = 0;
   2214 	transflag = 1;
   2215 	rval = -1;
   2216 
   2217 	switch (type) {
   2218 
   2219 	case TYPE_A:
   2220  /* XXXLUKEM: rate limit ascii send (get) */
   2221 		(void) alarm(curclass.timeout);
   2222 		while ((c = getc(instr)) != EOF) {
   2223 			if (urgflag && handleoobcmd())
   2224 				goto cleanup_send_data;
   2225 			byte_count++;
   2226 			if (c == '\n') {
   2227 				if (ferror(outstr))
   2228 					goto data_err;
   2229 				(void) putc('\r', outstr);
   2230 				if (isdata) {
   2231 					total_data_out++;
   2232 					total_data++;
   2233 				}
   2234 				total_bytes_out++;
   2235 				total_bytes++;
   2236 			}
   2237 			(void) putc(c, outstr);
   2238 			if (isdata) {
   2239 				total_data_out++;
   2240 				total_data++;
   2241 			}
   2242 			total_bytes_out++;
   2243 			total_bytes++;
   2244 			if ((byte_count % 4096) == 0)
   2245 				(void) alarm(curclass.timeout);
   2246 		}
   2247 		(void) alarm(0);
   2248 		fflush(outstr);
   2249 		if (ferror(instr))
   2250 			goto file_err;
   2251 		if (ferror(outstr))
   2252 			goto data_err;
   2253 		rval = 0;
   2254 		goto cleanup_send_data;
   2255 
   2256 	case TYPE_I:
   2257 	case TYPE_L:
   2258 		filefd = fileno(instr);
   2259 		netfd = fileno(outstr);
   2260 		switch (send_data_with_mmap(filefd, netfd, st, isdata)) {
   2261 
   2262 		case SS_SUCCESS:
   2263 			break;
   2264 
   2265 		case SS_ABORTED:
   2266 		case SS_NO_TRANSFER:
   2267 			goto cleanup_send_data;
   2268 
   2269 		case SS_FILE_ERROR:
   2270 			goto file_err;
   2271 
   2272 		case SS_DATA_ERROR:
   2273 			goto data_err;
   2274 		}
   2275 		rval = 0;
   2276 		goto cleanup_send_data;
   2277 
   2278 	default:
   2279 		reply(550, "Unimplemented TYPE %d in send_data", type);
   2280 		goto cleanup_send_data;
   2281 	}
   2282 
   2283  data_err:
   2284 	(void) alarm(0);
   2285 	perror_reply(426, "Data connection");
   2286 	goto cleanup_send_data;
   2287 
   2288  file_err:
   2289 	(void) alarm(0);
   2290 	perror_reply(551, "Error on input file");
   2291 	goto cleanup_send_data;
   2292 
   2293  cleanup_send_data:
   2294 	(void) alarm(0);
   2295 	transflag = 0;
   2296 	urgflag = 0;
   2297 	if (isdata) {
   2298 		total_files_out++;
   2299 		total_files++;
   2300 	}
   2301 	total_xfers_out++;
   2302 	total_xfers++;
   2303 	return (rval);
   2304 }
   2305 
   2306 /*
   2307  * Transfer data from peer to "outstr" using the appropriate encapulation of
   2308  * the data subject to Mode, Structure, and Type.
   2309  *
   2310  * N.B.: Form isn't handled.
   2311  */
   2312 static int
   2313 receive_data(FILE *instr, FILE *outstr)
   2314 {
   2315 	int	c, netfd, filefd, rval;
   2316 	int	volatile bare_lfs;
   2317 	off_t	byteswritten;
   2318 	char	*buf;
   2319 	size_t	readsize;
   2320 	struct sigaction sa, sa_saved;
   2321 	struct stat st;
   2322 
   2323 	memset(&sa, 0, sizeof(sa));
   2324 	sigfillset(&sa.sa_mask);
   2325 	sa.sa_flags = SA_RESTART;
   2326 	sa.sa_handler = lostconn;
   2327 	(void) sigaction(SIGALRM, &sa, &sa_saved);
   2328 
   2329 	bare_lfs = 0;
   2330 	urgflag = 0;
   2331 	transflag = 1;
   2332 	rval = -1;
   2333 	byteswritten = 0;
   2334 	buf = NULL;
   2335 
   2336 #define FILESIZECHECK(x) \
   2337 			do { \
   2338 				if (curclass.maxfilesize != -1 && \
   2339 				    (x) > curclass.maxfilesize) { \
   2340 					errno = EFBIG; \
   2341 					goto file_err; \
   2342 				} \
   2343 			} while (0)
   2344 
   2345 	switch (type) {
   2346 
   2347 	case TYPE_I:
   2348 	case TYPE_L:
   2349 		netfd = fileno(instr);
   2350 		filefd = fileno(outstr);
   2351 		(void) alarm(curclass.timeout);
   2352 		if (curclass.readsize)
   2353 			readsize = curclass.readsize;
   2354 		else if (fstat(filefd, &st))
   2355 			readsize = (size_t)st.st_blksize;
   2356 		else
   2357 			readsize = BUFSIZ;
   2358 		if ((buf = malloc(readsize)) == NULL) {
   2359 			perror_reply(451, "Local resource failure: malloc");
   2360 			goto cleanup_recv_data;
   2361 		}
   2362 		if (curclass.rateput) {
   2363 			while (1) {
   2364 				int d;
   2365 				struct timeval then, now, td;
   2366 				off_t bufrem;
   2367 
   2368 				(void)gettimeofday(&then, NULL);
   2369 				errno = c = d = 0;
   2370 				for (bufrem = curclass.rateput; bufrem > 0; ) {
   2371 					if ((c = read(netfd, buf,
   2372 					    MIN(readsize, bufrem))) <= 0)
   2373 						goto recvdone;
   2374 					if (urgflag && handleoobcmd())
   2375 						goto cleanup_recv_data;
   2376 					FILESIZECHECK(byte_count + c);
   2377 					if ((d = write(filefd, buf, c)) != c)
   2378 						goto file_err;
   2379 					(void) alarm(curclass.timeout);
   2380 					bufrem -= c;
   2381 					byte_count += c;
   2382 					total_data_in += c;
   2383 					total_data += c;
   2384 					total_bytes_in += c;
   2385 					total_bytes += c;
   2386 				}
   2387 				(void)gettimeofday(&now, NULL);
   2388 				timersub(&now, &then, &td);
   2389 				if (td.tv_sec == 0)
   2390 					usleep(1000000 - td.tv_usec);
   2391 			}
   2392 		} else {
   2393 			while ((c = read(netfd, buf, readsize)) > 0) {
   2394 				if (urgflag && handleoobcmd())
   2395 					goto cleanup_recv_data;
   2396 				FILESIZECHECK(byte_count + c);
   2397 				if (write(filefd, buf, c) != c)
   2398 					goto file_err;
   2399 				(void) alarm(curclass.timeout);
   2400 				byte_count += c;
   2401 				total_data_in += c;
   2402 				total_data += c;
   2403 				total_bytes_in += c;
   2404 				total_bytes += c;
   2405 			}
   2406 		}
   2407  recvdone:
   2408 		if (c < 0)
   2409 			goto data_err;
   2410 		rval = 0;
   2411 		goto cleanup_recv_data;
   2412 
   2413 	case TYPE_E:
   2414 		reply(553, "TYPE E not implemented.");
   2415 		goto cleanup_recv_data;
   2416 
   2417 	case TYPE_A:
   2418 		(void) alarm(curclass.timeout);
   2419  /* XXXLUKEM: rate limit ascii receive (put) */
   2420 		while ((c = getc(instr)) != EOF) {
   2421 			if (urgflag && handleoobcmd())
   2422 				goto cleanup_recv_data;
   2423 			byte_count++;
   2424 			total_data_in++;
   2425 			total_data++;
   2426 			total_bytes_in++;
   2427 			total_bytes++;
   2428 			if ((byte_count % 4096) == 0)
   2429 				(void) alarm(curclass.timeout);
   2430 			if (c == '\n')
   2431 				bare_lfs++;
   2432 			while (c == '\r') {
   2433 				if (ferror(outstr))
   2434 					goto data_err;
   2435 				if ((c = getc(instr)) != '\n') {
   2436 					byte_count++;
   2437 					total_data_in++;
   2438 					total_data++;
   2439 					total_bytes_in++;
   2440 					total_bytes++;
   2441 					if ((byte_count % 4096) == 0)
   2442 						(void) alarm(curclass.timeout);
   2443 					byteswritten++;
   2444 					FILESIZECHECK(byteswritten);
   2445 					(void) putc ('\r', outstr);
   2446 					if (c == '\0' || c == EOF)
   2447 						goto contin2;
   2448 				}
   2449 			}
   2450 			byteswritten++;
   2451 			FILESIZECHECK(byteswritten);
   2452 			(void) putc(c, outstr);
   2453  contin2:	;
   2454 		}
   2455 		(void) alarm(0);
   2456 		fflush(outstr);
   2457 		if (ferror(instr))
   2458 			goto data_err;
   2459 		if (ferror(outstr))
   2460 			goto file_err;
   2461 		if (bare_lfs) {
   2462 			reply(-226,
   2463 			    "WARNING! %d bare linefeeds received in ASCII mode",
   2464 			    bare_lfs);
   2465 			reply(0, "File may not have transferred correctly.");
   2466 		}
   2467 		rval = 0;
   2468 		goto cleanup_recv_data;
   2469 
   2470 	default:
   2471 		reply(550, "Unimplemented TYPE %d in receive_data", type);
   2472 		goto cleanup_recv_data;
   2473 	}
   2474 #undef FILESIZECHECK
   2475 
   2476  data_err:
   2477 	(void) alarm(0);
   2478 	perror_reply(426, "Data Connection");
   2479 	goto cleanup_recv_data;
   2480 
   2481  file_err:
   2482 	(void) alarm(0);
   2483 	perror_reply(452, "Error writing file");
   2484 	goto cleanup_recv_data;
   2485 
   2486  cleanup_recv_data:
   2487 	(void) alarm(0);
   2488 	(void) sigaction(SIGALRM, &sa_saved, NULL);
   2489 	if (buf)
   2490 		free(buf);
   2491 	transflag = 0;
   2492 	urgflag = 0;
   2493 	total_files_in++;
   2494 	total_files++;
   2495 	total_xfers_in++;
   2496 	total_xfers++;
   2497 	return (rval);
   2498 }
   2499 
   2500 void
   2501 statcmd(void)
   2502 {
   2503 	struct sockinet *su = NULL;
   2504 	static char hbuf[NI_MAXHOST], sbuf[NI_MAXSERV];
   2505 	unsigned char *a, *p;
   2506 	int ispassive, af;
   2507 	off_t otbi, otbo, otb;
   2508 
   2509 	a = p = (unsigned char *)NULL;
   2510 
   2511 	reply(-211, "%s FTP server status:", hostname);
   2512 	reply(0, "Version: %s", EMPTYSTR(version) ? "<suppressed>" : version);
   2513 	hbuf[0] = '\0';
   2514 	if (!getnameinfo((struct sockaddr *)&his_addr.si_su, his_addr.su_len,
   2515 			hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST)
   2516 	    && strcmp(remotehost, hbuf) != 0)
   2517 		reply(0, "Connected to %s (%s)", remotehost, hbuf);
   2518 	else
   2519 		reply(0, "Connected to %s", remotehost);
   2520 
   2521 	if (logged_in) {
   2522 		if (curclass.type == CLASS_GUEST)
   2523 			reply(0, "Logged in anonymously");
   2524 		else
   2525 			reply(0, "Logged in as %s%s", pw->pw_name,
   2526 			    curclass.type == CLASS_CHROOT ? " (chroot)" : "");
   2527 	} else if (askpasswd)
   2528 		reply(0, "Waiting for password");
   2529 	else
   2530 		reply(0, "Waiting for user name");
   2531 	cprintf(stdout, "    TYPE: %s", typenames[type]);
   2532 	if (type == TYPE_A || type == TYPE_E)
   2533 		cprintf(stdout, ", FORM: %s", formnames[form]);
   2534 	if (type == TYPE_L) {
   2535 #if NBBY == 8
   2536 		cprintf(stdout, " %d", NBBY);
   2537 #else
   2538 			/* XXX: `bytesize' needs to be defined in this case */
   2539 		cprintf(stdout, " %d", bytesize);
   2540 #endif
   2541 	}
   2542 	cprintf(stdout, "; STRUcture: %s; transfer MODE: %s\r\n",
   2543 	    strunames[stru], modenames[mode]);
   2544 	ispassive = 0;
   2545 	if (data != -1) {
   2546 		reply(0, "Data connection open");
   2547 		su = NULL;
   2548 	} else if (pdata != -1) {
   2549 		reply(0, "in Passive mode");
   2550 		if (curclass.advertise.su_len != 0)
   2551 			su = &curclass.advertise;
   2552 		else
   2553 			su = &pasv_addr;
   2554 		ispassive = 1;
   2555 		goto printaddr;
   2556 	} else if (usedefault == 0) {
   2557 		su = (struct sockinet *)&data_dest;
   2558 
   2559 		if (epsvall) {
   2560 			reply(0, "EPSV only mode (EPSV ALL)");
   2561 			goto epsvonly;
   2562 		}
   2563  printaddr:
   2564 							/* PASV/PORT */
   2565 		if (su->su_family == AF_INET) {
   2566 			a = (unsigned char *) &su->su_addr;
   2567 			p = (unsigned char *) &su->su_port;
   2568 #define UC(b) (((int) b) & 0xff)
   2569 			reply(0, "%s (%d,%d,%d,%d,%d,%d)",
   2570 				ispassive ? "PASV" : "PORT" ,
   2571 				UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
   2572 				UC(p[0]), UC(p[1]));
   2573 		}
   2574 
   2575 							/* LPSV/LPRT */
   2576 	    {
   2577 		int alen, i;
   2578 
   2579 		alen = 0;
   2580 		switch (su->su_family) {
   2581 		case AF_INET:
   2582 			a = (unsigned char *) &su->su_addr;
   2583 			p = (unsigned char *) &su->su_port;
   2584 			alen = sizeof(su->su_addr);
   2585 			af = 4;
   2586 			break;
   2587 #ifdef INET6
   2588 		case AF_INET6:
   2589 			a = (unsigned char *) &su->su_6addr;
   2590 			p = (unsigned char *) &su->su_port;
   2591 			alen = sizeof(su->su_6addr);
   2592 			af = 6;
   2593 			break;
   2594 #endif
   2595 		default:
   2596 			af = 0;
   2597 			break;
   2598 		}
   2599 		if (af) {
   2600 			cprintf(stdout, "    %s (%d,%d",
   2601 			    ispassive ? "LPSV" : "LPRT", af, alen);
   2602 			for (i = 0; i < alen; i++)
   2603 				cprintf(stdout, ",%d", UC(a[i]));
   2604 			cprintf(stdout, ",%d,%d,%d)\r\n",
   2605 			    2, UC(p[0]), UC(p[1]));
   2606 #undef UC
   2607 		}
   2608 	    }
   2609 
   2610 		/* EPRT/EPSV */
   2611  epsvonly:
   2612 		af = af2epsvproto(su->su_family);
   2613 		hbuf[0] = '\0';
   2614 		if (af > 0) {
   2615 			struct sockinet tmp;
   2616 
   2617 			tmp = *su;
   2618 #ifdef INET6
   2619 			if (tmp.su_family == AF_INET6)
   2620 				tmp.su_scope_id = 0;
   2621 #endif
   2622 			if (getnameinfo((struct sockaddr *)&tmp.si_su,
   2623 			    tmp.su_len, hbuf, sizeof(hbuf), sbuf, sizeof(sbuf),
   2624 			    NI_NUMERICHOST | NI_NUMERICSERV) == 0)
   2625 				reply(0, "%s (|%d|%s|%s|)",
   2626 				    ispassive ? "EPSV" : "EPRT",
   2627 				    af, hbuf, sbuf);
   2628 		}
   2629 	} else
   2630 		reply(0, "No data connection");
   2631 
   2632 	if (logged_in) {
   2633 		reply(0,
   2634 		    "Data sent:        " LLF " byte%s in " LLF " file%s",
   2635 		    (LLT)total_data_out, PLURAL(total_data_out),
   2636 		    (LLT)total_files_out, PLURAL(total_files_out));
   2637 		reply(0,
   2638 		    "Data received:    " LLF " byte%s in " LLF " file%s",
   2639 		    (LLT)total_data_in, PLURAL(total_data_in),
   2640 		    (LLT)total_files_in, PLURAL(total_files_in));
   2641 		reply(0,
   2642 		    "Total data:       " LLF " byte%s in " LLF " file%s",
   2643 		    (LLT)total_data, PLURAL(total_data),
   2644 		    (LLT)total_files, PLURAL(total_files));
   2645 	}
   2646 	otbi = total_bytes_in;
   2647 	otbo = total_bytes_out;
   2648 	otb = total_bytes;
   2649 	reply(0, "Traffic sent:     " LLF " byte%s in " LLF " transfer%s",
   2650 	    (LLT)otbo, PLURAL(otbo),
   2651 	    (LLT)total_xfers_out, PLURAL(total_xfers_out));
   2652 	reply(0, "Traffic received: " LLF " byte%s in " LLF " transfer%s",
   2653 	    (LLT)otbi, PLURAL(otbi),
   2654 	    (LLT)total_xfers_in, PLURAL(total_xfers_in));
   2655 	reply(0, "Total traffic:    " LLF " byte%s in " LLF " transfer%s",
   2656 	    (LLT)otb, PLURAL(otb),
   2657 	    (LLT)total_xfers, PLURAL(total_xfers));
   2658 
   2659 	if (logged_in && !CURCLASS_FLAGS_ISSET(private)) {
   2660 		struct ftpconv *cp;
   2661 
   2662 		reply(0, "%s", "");
   2663 		reply(0, "Class: %s, type: %s",
   2664 		    curclass.classname, CURCLASSTYPE);
   2665 		reply(0, "Check PORT/LPRT commands: %sabled",
   2666 		    CURCLASS_FLAGS_ISSET(checkportcmd) ? "en" : "dis");
   2667 		if (! EMPTYSTR(curclass.display))
   2668 			reply(0, "Display file: %s", curclass.display);
   2669 		if (! EMPTYSTR(curclass.notify))
   2670 			reply(0, "Notify fileglob: %s", curclass.notify);
   2671 		reply(0, "Idle timeout: " LLF ", maximum timeout: " LLF,
   2672 		    (LLT)curclass.timeout, (LLT)curclass.maxtimeout);
   2673 		reply(0, "Current connections: %d", connections);
   2674 		if (curclass.limit == -1)
   2675 			reply(0, "Maximum connections: unlimited");
   2676 		else
   2677 			reply(0, "Maximum connections: " LLF,
   2678 			    (LLT)curclass.limit);
   2679 		if (curclass.limitfile)
   2680 			reply(0, "Connection limit exceeded message file: %s",
   2681 			    conffilename(curclass.limitfile));
   2682 		if (! EMPTYSTR(curclass.chroot))
   2683 			reply(0, "Chroot format: %s", curclass.chroot);
   2684 		reply(0, "Deny bad ftpusers(5) quickly: %sabled",
   2685 		    CURCLASS_FLAGS_ISSET(denyquick) ? "en" : "dis");
   2686 		if (! EMPTYSTR(curclass.homedir))
   2687 			reply(0, "Homedir format: %s", curclass.homedir);
   2688 		if (curclass.maxfilesize == -1)
   2689 			reply(0, "Maximum file size: unlimited");
   2690 		else
   2691 			reply(0, "Maximum file size: " LLF,
   2692 			    (LLT)curclass.maxfilesize);
   2693 		if (! EMPTYSTR(curclass.motd))
   2694 			reply(0, "MotD file: %s", conffilename(curclass.motd));
   2695 		reply(0,
   2696 	    "Modify commands (CHMOD, DELE, MKD, RMD, RNFR, UMASK): %sabled",
   2697 		    CURCLASS_FLAGS_ISSET(modify) ? "en" : "dis");
   2698 		reply(0, "Upload commands (APPE, STOR, STOU): %sabled",
   2699 		    CURCLASS_FLAGS_ISSET(upload) ? "en" : "dis");
   2700 		reply(0, "Sanitize file names: %sabled",
   2701 		    CURCLASS_FLAGS_ISSET(sanenames) ? "en" : "dis");
   2702 		reply(0, "PASV/LPSV/EPSV connections: %sabled",
   2703 		    CURCLASS_FLAGS_ISSET(passive) ? "en" : "dis");
   2704 		if (curclass.advertise.su_len != 0) {
   2705 			char buf[50];	/* big enough for IPv6 address */
   2706 			const char *bp;
   2707 
   2708 			bp = inet_ntop(curclass.advertise.su_family,
   2709 			    (void *)&curclass.advertise.su_addr,
   2710 			    buf, sizeof(buf));
   2711 			if (bp != NULL)
   2712 				reply(0, "PASV advertise address: %s", bp);
   2713 		}
   2714 		if (curclass.portmin && curclass.portmax)
   2715 			reply(0, "PASV port range: " LLF " - " LLF,
   2716 			    (LLT)curclass.portmin, (LLT)curclass.portmax);
   2717 		if (curclass.rateget)
   2718 			reply(0, "Rate get limit: " LLF " bytes/sec",
   2719 			    (LLT)curclass.rateget);
   2720 		else
   2721 			reply(0, "Rate get limit: disabled");
   2722 		if (curclass.rateput)
   2723 			reply(0, "Rate put limit: " LLF " bytes/sec",
   2724 			    (LLT)curclass.rateput);
   2725 		else
   2726 			reply(0, "Rate put limit: disabled");
   2727 		if (curclass.mmapsize)
   2728 			reply(0, "Mmap size: " LLF, (LLT)curclass.mmapsize);
   2729 		else
   2730 			reply(0, "Mmap size: disabled");
   2731 		if (curclass.readsize)
   2732 			reply(0, "Read size: " LLF, (LLT)curclass.readsize);
   2733 		else
   2734 			reply(0, "Read size: default");
   2735 		if (curclass.writesize)
   2736 			reply(0, "Write size: " LLF, (LLT)curclass.writesize);
   2737 		else
   2738 			reply(0, "Write size: default");
   2739 		if (curclass.recvbufsize)
   2740 			reply(0, "Receive buffer size: " LLF,
   2741 			    (LLT)curclass.recvbufsize);
   2742 		else
   2743 			reply(0, "Receive buffer size: default");
   2744 		if (curclass.sendbufsize)
   2745 			reply(0, "Send buffer size: " LLF,
   2746 			    (LLT)curclass.sendbufsize);
   2747 		else
   2748 			reply(0, "Send buffer size: default");
   2749 		if (curclass.sendlowat)
   2750 			reply(0, "Send low water mark: " LLF,
   2751 			    (LLT)curclass.sendlowat);
   2752 		else
   2753 			reply(0, "Send low water mark: default");
   2754 		reply(0, "Umask: %.04o", curclass.umask);
   2755 		for (cp = curclass.conversions; cp != NULL; cp=cp->next) {
   2756 			if (cp->suffix == NULL || cp->types == NULL ||
   2757 			    cp->command == NULL)
   2758 				continue;
   2759 			reply(0, "Conversion: %s [%s] disable: %s, command: %s",
   2760 			    cp->suffix, cp->types, cp->disable, cp->command);
   2761 		}
   2762 	}
   2763 
   2764 	reply(211, "End of status");
   2765 }
   2766 
   2767 void
   2768 fatal(const char *s)
   2769 {
   2770 
   2771 	reply(451, "Error in server: %s\n", s);
   2772 	reply(221, "Closing connection due to server error.");
   2773 	dologout(0);
   2774 	/* NOTREACHED */
   2775 }
   2776 
   2777 /*
   2778  * reply() --
   2779  *	depending on the value of n, display fmt with a trailing CRLF and
   2780  *	prefix of:
   2781  *	n < -1		prefix the message with abs(n) + "-"	(initial line)
   2782  *	n == 0		prefix the message with 4 spaces	(middle lines)
   2783  *	n >  0		prefix the message with n + " "		(final line)
   2784  */
   2785 void
   2786 reply(int n, const char *fmt, ...)
   2787 {
   2788 	char	msg[MAXPATHLEN * 2 + 100];
   2789 	size_t	b;
   2790 	va_list	ap;
   2791 
   2792 	b = 0;
   2793 	if (n == 0)
   2794 		b = snprintf(msg, sizeof(msg), "    ");
   2795 	else if (n < 0)
   2796 		b = snprintf(msg, sizeof(msg), "%d-", -n);
   2797 	else
   2798 		b = snprintf(msg, sizeof(msg), "%d ", n);
   2799 	va_start(ap, fmt);
   2800 	vsnprintf(msg + b, sizeof(msg) - b, fmt, ap);
   2801 	va_end(ap);
   2802 	cprintf(stdout, "%s\r\n", msg);
   2803 	(void)fflush(stdout);
   2804 	if (ftpd_debug)
   2805 		syslog(LOG_DEBUG, "<--- %s", msg);
   2806 }
   2807 
   2808 static void
   2809 logremotehost(struct sockinet *who)
   2810 {
   2811 
   2812 	if (getnameinfo((struct sockaddr *)&who->si_su,
   2813 	    who->su_len, remotehost, sizeof(remotehost), NULL, 0,
   2814 	    getnameopts))
   2815 		strlcpy(remotehost, "?", sizeof(remotehost));
   2816 
   2817 #if defined(HAVE_SETPROCTITLE)
   2818 	snprintf(proctitle, sizeof(proctitle), "%s: connected", remotehost);
   2819 	setproctitle("%s", proctitle);
   2820 #endif /* defined(HAVE_SETPROCTITLE) */
   2821 	if (logging)
   2822 		syslog(LOG_INFO, "connection from %s to %s",
   2823 		    remotehost, hostname);
   2824 }
   2825 
   2826 /*
   2827  * Record logout in wtmp file and exit with supplied status.
   2828  * NOTE: because this is called from signal handlers it cannot
   2829  *       use stdio (or call other functions that use stdio).
   2830  */
   2831 void
   2832 dologout(int status)
   2833 {
   2834 	/*
   2835 	* Prevent reception of SIGURG from resulting in a resumption
   2836 	* back to the main program loop.
   2837 	*/
   2838 	transflag = 0;
   2839 	logout_utmp();
   2840 	if (logged_in) {
   2841 #ifdef KERBEROS
   2842 		if (!notickets && krbtkfile_env)
   2843 			unlink(krbtkfile_env);
   2844 #endif
   2845 	}
   2846 	/* beware of flushing buffers after a SIGPIPE */
   2847 	if (xferlogfd != -1)
   2848 		close(xferlogfd);
   2849 	_exit(status);
   2850 }
   2851 
   2852 void
   2853 abor(void)
   2854 {
   2855 
   2856 	if (!transflag)
   2857 		return;
   2858 	tmpline[0] = '\0';
   2859 	is_oob = 0;
   2860 	reply(426, "Transfer aborted. Data connection closed.");
   2861 	reply(226, "Abort successful");
   2862 	transflag = 0;		/* flag that the transfer has aborted */
   2863 }
   2864 
   2865 void
   2866 statxfer(void)
   2867 {
   2868 
   2869 	if (!transflag)
   2870 		return;
   2871 	tmpline[0] = '\0';
   2872 	is_oob = 0;
   2873 	if (file_size != (off_t) -1)
   2874 		reply(213,
   2875 		    "Status: " LLF " of " LLF " byte%s transferred",
   2876 		    (LLT)byte_count, (LLT)file_size,
   2877 		    PLURAL(byte_count));
   2878 	else
   2879 		reply(213, "Status: " LLF " byte%s transferred",
   2880 		    (LLT)byte_count, PLURAL(byte_count));
   2881 }
   2882 
   2883 /*
   2884  * Call when urgflag != 0 to handle Out Of Band commands.
   2885  * Returns non zero if the OOB command aborted the transfer
   2886  * by setting transflag to 0. (c.f., "ABOR").
   2887  */
   2888 static int
   2889 handleoobcmd()
   2890 {
   2891 	char *cp;
   2892 
   2893 	if (!urgflag)
   2894 		return (0);
   2895 	urgflag = 0;
   2896 	/* only process if transfer occurring */
   2897 	if (!transflag)
   2898 		return (0);
   2899 	cp = tmpline;
   2900 	if (getline(cp, sizeof(tmpline), stdin) == NULL) {
   2901 		reply(221, "You could at least say goodbye.");
   2902 		dologout(0);
   2903 	}
   2904 		/*
   2905 		 * Manually parse OOB commands, because we can't
   2906 		 * recursively call the yacc parser...
   2907 		 */
   2908 	if (strcasecmp(cp, "ABOR\r\n") == 0) {
   2909 		abor();
   2910 	} else if (strcasecmp(cp, "STAT\r\n") == 0) {
   2911 		statxfer();
   2912 	} else {
   2913 		/* XXX: error with "500 unknown command" ? */
   2914 	}
   2915 	return (transflag == 0);
   2916 }
   2917 
   2918 static int
   2919 bind_pasv_addr(void)
   2920 {
   2921 	static int passiveport;
   2922 	int port, len;
   2923 
   2924 	len = pasv_addr.su_len;
   2925 	if (curclass.portmin == 0 && curclass.portmax == 0) {
   2926 		pasv_addr.su_port = 0;
   2927 		return (bind(pdata, (struct sockaddr *)&pasv_addr.si_su, len));
   2928 	}
   2929 
   2930 	if (passiveport == 0) {
   2931 		srand(getpid());
   2932 		passiveport = rand() % (curclass.portmax - curclass.portmin)
   2933 		    + curclass.portmin;
   2934 	}
   2935 
   2936 	port = passiveport;
   2937 	while (1) {
   2938 		port++;
   2939 		if (port > curclass.portmax)
   2940 			port = curclass.portmin;
   2941 		else if (port == passiveport) {
   2942 			errno = EAGAIN;
   2943 			return (-1);
   2944 		}
   2945 		pasv_addr.su_port = htons(port);
   2946 		if (bind(pdata, (struct sockaddr *)&pasv_addr.si_su, len) == 0)
   2947 			break;
   2948 		if (errno != EADDRINUSE)
   2949 			return (-1);
   2950 	}
   2951 	passiveport = port;
   2952 	return (0);
   2953 }
   2954 
   2955 /*
   2956  * Note: a response of 425 is not mentioned as a possible response to
   2957  *	the PASV command in RFC959. However, it has been blessed as
   2958  *	a legitimate response by Jon Postel in a telephone conversation
   2959  *	with Rick Adams on 25 Jan 89.
   2960  */
   2961 void
   2962 passive(void)
   2963 {
   2964 	socklen_t len, recvbufsize;
   2965 	char *p, *a;
   2966 
   2967 	if (pdata >= 0)
   2968 		close(pdata);
   2969 	pdata = socket(AF_INET, SOCK_STREAM, 0);
   2970 	if (pdata < 0 || !logged_in) {
   2971 		perror_reply(425, "Can't open passive connection");
   2972 		return;
   2973 	}
   2974 	pasv_addr = ctrl_addr;
   2975 
   2976 	if (bind_pasv_addr() < 0)
   2977 		goto pasv_error;
   2978 	len = pasv_addr.su_len;
   2979 	if (getsockname(pdata, (struct sockaddr *) &pasv_addr.si_su, &len) < 0)
   2980 		goto pasv_error;
   2981 	pasv_addr.su_len = len;
   2982 	if (curclass.recvbufsize) {
   2983 		recvbufsize = curclass.recvbufsize;
   2984 		if (setsockopt(pdata, SOL_SOCKET, SO_RCVBUF, &recvbufsize,
   2985 			       sizeof(int)) == -1)
   2986 			syslog(LOG_WARNING, "setsockopt(SO_RCVBUF, %d): %m",
   2987 			       recvbufsize);
   2988 	}
   2989 	if (listen(pdata, 1) < 0)
   2990 		goto pasv_error;
   2991 	if (curclass.advertise.su_len != 0)
   2992 		a = (char *) &curclass.advertise.su_addr;
   2993 	else
   2994 		a = (char *) &pasv_addr.su_addr;
   2995 	p = (char *) &pasv_addr.su_port;
   2996 
   2997 #define UC(b) (((int) b) & 0xff)
   2998 
   2999 	reply(227, "Entering Passive Mode (%d,%d,%d,%d,%d,%d)", UC(a[0]),
   3000 		UC(a[1]), UC(a[2]), UC(a[3]), UC(p[0]), UC(p[1]));
   3001 	return;
   3002 
   3003  pasv_error:
   3004 	(void) close(pdata);
   3005 	pdata = -1;
   3006 	perror_reply(425, "Can't open passive connection");
   3007 	return;
   3008 }
   3009 
   3010 /*
   3011  * convert protocol identifier to/from AF
   3012  */
   3013 int
   3014 lpsvproto2af(int proto)
   3015 {
   3016 
   3017 	switch (proto) {
   3018 	case 4:
   3019 		return AF_INET;
   3020 #ifdef INET6
   3021 	case 6:
   3022 		return AF_INET6;
   3023 #endif
   3024 	default:
   3025 		return -1;
   3026 	}
   3027 }
   3028 
   3029 int
   3030 af2lpsvproto(int af)
   3031 {
   3032 
   3033 	switch (af) {
   3034 	case AF_INET:
   3035 		return 4;
   3036 #ifdef INET6
   3037 	case AF_INET6:
   3038 		return 6;
   3039 #endif
   3040 	default:
   3041 		return -1;
   3042 	}
   3043 }
   3044 
   3045 int
   3046 epsvproto2af(int proto)
   3047 {
   3048 
   3049 	switch (proto) {
   3050 	case 1:
   3051 		return AF_INET;
   3052 #ifdef INET6
   3053 	case 2:
   3054 		return AF_INET6;
   3055 #endif
   3056 	default:
   3057 		return -1;
   3058 	}
   3059 }
   3060 
   3061 int
   3062 af2epsvproto(int af)
   3063 {
   3064 
   3065 	switch (af) {
   3066 	case AF_INET:
   3067 		return 1;
   3068 #ifdef INET6
   3069 	case AF_INET6:
   3070 		return 2;
   3071 #endif
   3072 	default:
   3073 		return -1;
   3074 	}
   3075 }
   3076 
   3077 /*
   3078  * 228 Entering Long Passive Mode (af, hal, h1, h2, h3,..., pal, p1, p2...)
   3079  * 229 Entering Extended Passive Mode (|||port|)
   3080  */
   3081 void
   3082 long_passive(char *cmd, int pf)
   3083 {
   3084 	socklen_t len;
   3085 	char *p, *a;
   3086 
   3087 	if (!logged_in) {
   3088 		syslog(LOG_NOTICE, "long passive but not logged in");
   3089 		reply(503, "Login with USER first.");
   3090 		return;
   3091 	}
   3092 
   3093 	if (pf != PF_UNSPEC && ctrl_addr.su_family != pf) {
   3094 		/*
   3095 		 * XXX: only EPRT/EPSV ready clients will understand this
   3096 		 */
   3097 		if (strcmp(cmd, "EPSV") != 0)
   3098 			reply(501, "Network protocol mismatch"); /*XXX*/
   3099 		else
   3100 			epsv_protounsupp("Network protocol mismatch");
   3101 
   3102 		return;
   3103 	}
   3104 
   3105 	if (pdata >= 0)
   3106 		close(pdata);
   3107 	pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0);
   3108 	if (pdata < 0) {
   3109 		perror_reply(425, "Can't open passive connection");
   3110 		return;
   3111 	}
   3112 	pasv_addr = ctrl_addr;
   3113 	if (bind_pasv_addr() < 0)
   3114 		goto pasv_error;
   3115 	len = pasv_addr.su_len;
   3116 	if (getsockname(pdata, (struct sockaddr *) &pasv_addr.si_su, &len) < 0)
   3117 		goto pasv_error;
   3118 	pasv_addr.su_len = len;
   3119 	if (listen(pdata, 1) < 0)
   3120 		goto pasv_error;
   3121 	p = (char *) &pasv_addr.su_port;
   3122 
   3123 #define UC(b) (((int) b) & 0xff)
   3124 
   3125 	if (strcmp(cmd, "LPSV") == 0) {
   3126 		struct sockinet *advert;
   3127 
   3128 		if (curclass.advertise.su_len != 0)
   3129 			advert = &curclass.advertise;
   3130 		else
   3131 			advert = &pasv_addr;
   3132 		switch (advert->su_family) {
   3133 		case AF_INET:
   3134 			a = (char *) &advert->su_addr;
   3135 			reply(228,
   3136     "Entering Long Passive Mode (%d,%d,%d,%d,%d,%d,%d,%d,%d)",
   3137 				4, 4, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
   3138 				2, UC(p[0]), UC(p[1]));
   3139 			return;
   3140 #ifdef INET6
   3141 		case AF_INET6:
   3142 			a = (char *) &advert->su_6addr;
   3143 			reply(228,
   3144     "Entering Long Passive Mode (%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d)",
   3145 				6, 16,
   3146 				UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]),
   3147 				UC(a[4]), UC(a[5]), UC(a[6]), UC(a[7]),
   3148 				UC(a[8]), UC(a[9]), UC(a[10]), UC(a[11]),
   3149 				UC(a[12]), UC(a[13]), UC(a[14]), UC(a[15]),
   3150 				2, UC(p[0]), UC(p[1]));
   3151 			return;
   3152 #endif
   3153 		}
   3154 #undef UC
   3155 	} else if (strcmp(cmd, "EPSV") == 0) {
   3156 		switch (pasv_addr.su_family) {
   3157 		case AF_INET:
   3158 #ifdef INET6
   3159 		case AF_INET6:
   3160 #endif
   3161 			reply(229, "Entering Extended Passive Mode (|||%d|)",
   3162 			    ntohs(pasv_addr.su_port));
   3163 			return;
   3164 		}
   3165 	} else {
   3166 		/* more proper error code? */
   3167 	}
   3168 
   3169  pasv_error:
   3170 	(void) close(pdata);
   3171 	pdata = -1;
   3172 	perror_reply(425, "Can't open passive connection");
   3173 	return;
   3174 }
   3175 
   3176 int
   3177 extended_port(const char *arg)
   3178 {
   3179 	char *tmp = NULL;
   3180 	char *result[3];
   3181 	char *p, *q;
   3182 	char delim;
   3183 	struct addrinfo hints;
   3184 	struct addrinfo *res = NULL;
   3185 	int i;
   3186 	unsigned long proto;
   3187 
   3188 	tmp = ftpd_strdup(arg);
   3189 	p = tmp;
   3190 	delim = p[0];
   3191 	p++;
   3192 	memset(result, 0, sizeof(result));
   3193 	for (i = 0; i < 3; i++) {
   3194 		q = strchr(p, delim);
   3195 		if (!q || *q != delim)
   3196 			goto parsefail;
   3197 		*q++ = '\0';
   3198 		result[i] = p;
   3199 		p = q;
   3200 	}
   3201 
   3202 			/* some more sanity checks */
   3203 	errno = 0;
   3204 	p = NULL;
   3205 	(void)strtoul(result[2], &p, 10);
   3206 	if (errno || !*result[2] || *p)
   3207 		goto parsefail;
   3208 	errno = 0;
   3209 	p = NULL;
   3210 	proto = strtoul(result[0], &p, 10);
   3211 	if (errno || !*result[0] || *p)
   3212 		goto protounsupp;
   3213 
   3214 	memset(&hints, 0, sizeof(hints));
   3215 	hints.ai_family = epsvproto2af((int)proto);
   3216 	if (hints.ai_family < 0)
   3217 		goto protounsupp;
   3218 	hints.ai_socktype = SOCK_STREAM;
   3219 	hints.ai_flags = AI_NUMERICHOST;
   3220 	if (getaddrinfo(result[1], result[2], &hints, &res))
   3221 		goto parsefail;
   3222 	if (res->ai_next)
   3223 		goto parsefail;
   3224 	if (sizeof(data_dest) < res->ai_addrlen)
   3225 		goto parsefail;
   3226 	memcpy(&data_dest.si_su, res->ai_addr, res->ai_addrlen);
   3227 	data_dest.su_len = res->ai_addrlen;
   3228 #ifdef INET6
   3229 	if (his_addr.su_family == AF_INET6 &&
   3230 	    data_dest.su_family == AF_INET6) {
   3231 			/* XXX: more sanity checks! */
   3232 		data_dest.su_scope_id = his_addr.su_scope_id;
   3233 	}
   3234 #endif
   3235 
   3236 	if (tmp != NULL)
   3237 		free(tmp);
   3238 	if (res)
   3239 		freeaddrinfo(res);
   3240 	return 0;
   3241 
   3242  parsefail:
   3243 	reply(500, "Invalid argument, rejected.");
   3244 	usedefault = 1;
   3245 	if (tmp != NULL)
   3246 		free(tmp);
   3247 	if (res)
   3248 		freeaddrinfo(res);
   3249 	return -1;
   3250 
   3251  protounsupp:
   3252 	epsv_protounsupp("Protocol not supported");
   3253 	usedefault = 1;
   3254 	if (tmp != NULL)
   3255 		free(tmp);
   3256 	return -1;
   3257 }
   3258 
   3259 /*
   3260  * 522 Protocol not supported (proto,...)
   3261  * as we assume address family for control and data connections are the same,
   3262  * we do not return the list of address families we support - instead, we
   3263  * return the address family of the control connection.
   3264  */
   3265 void
   3266 epsv_protounsupp(const char *message)
   3267 {
   3268 	int proto;
   3269 
   3270 	proto = af2epsvproto(ctrl_addr.su_family);
   3271 	if (proto < 0)
   3272 		reply(501, "%s", message);	/* XXX */
   3273 	else
   3274 		reply(522, "%s, use (%d)", message, proto);
   3275 }
   3276 
   3277 /*
   3278  * Generate unique name for file with basename "local".
   3279  * The file named "local" is already known to exist.
   3280  * Generates failure reply on error.
   3281  *
   3282  * XXX:	this function should under go changes similar to
   3283  *	the mktemp(3)/mkstemp(3) changes.
   3284  */
   3285 static char *
   3286 gunique(const char *local)
   3287 {
   3288 	static char new[MAXPATHLEN];
   3289 	struct stat st;
   3290 	char *cp;
   3291 	int count;
   3292 
   3293 	cp = strrchr(local, '/');
   3294 	if (cp)
   3295 		*cp = '\0';
   3296 	if (stat(cp ? local : ".", &st) < 0) {
   3297 		perror_reply(553, cp ? local : ".");
   3298 		return (NULL);
   3299 	}
   3300 	if (cp)
   3301 		*cp = '/';
   3302 	for (count = 1; count < 100; count++) {
   3303 		(void)snprintf(new, sizeof(new) - 1, "%s.%d", local, count);
   3304 		if (stat(new, &st) < 0)
   3305 			return (new);
   3306 	}
   3307 	reply(452, "Unique file name cannot be created.");
   3308 	return (NULL);
   3309 }
   3310 
   3311 /*
   3312  * Format and send reply containing system error number.
   3313  */
   3314 void
   3315 perror_reply(int code, const char *string)
   3316 {
   3317 	int save_errno;
   3318 
   3319 	save_errno = errno;
   3320 	reply(code, "%s: %s.", string, strerror(errno));
   3321 	errno = save_errno;
   3322 }
   3323 
   3324 static char *onefile[] = {
   3325 	"",
   3326 	0
   3327 };
   3328 
   3329 void
   3330 send_file_list(const char *whichf)
   3331 {
   3332 	struct stat st;
   3333 	DIR *dirp;
   3334 	struct dirent *dir;
   3335 	FILE *volatile dout;
   3336 	char **volatile dirlist;
   3337 	char *dirname, *p;
   3338 	char *notglob;
   3339 	int volatile simple;
   3340 	int volatile freeglob;
   3341 	glob_t gl;
   3342 
   3343 	dirp = NULL;
   3344 	dout = NULL;
   3345 	notglob = NULL;
   3346 	simple = 0;
   3347 	freeglob = 0;
   3348 	urgflag = 0;
   3349 
   3350 	p = NULL;
   3351 	if (strpbrk(whichf, "~{[*?") != NULL) {
   3352 		int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE|GLOB_LIMIT;
   3353 
   3354 		memset(&gl, 0, sizeof(gl));
   3355 		freeglob = 1;
   3356 		if (glob(whichf, flags, 0, &gl)) {
   3357 			reply(450, "Not found");
   3358 			goto cleanup_send_file_list;
   3359 		} else if (gl.gl_pathc == 0) {
   3360 			errno = ENOENT;
   3361 			perror_reply(450, whichf);
   3362 			goto cleanup_send_file_list;
   3363 		}
   3364 		dirlist = gl.gl_pathv;
   3365 	} else {
   3366 		notglob = ftpd_strdup(whichf);
   3367 		onefile[0] = notglob;
   3368 		dirlist = onefile;
   3369 		simple = 1;
   3370 	}
   3371 					/* XXX: } for vi sm */
   3372 
   3373 	while ((dirname = *dirlist++) != NULL) {
   3374 		int trailingslash = 0;
   3375 
   3376 		if (stat(dirname, &st) < 0) {
   3377 			/*
   3378 			 * If user typed "ls -l", etc, and the client
   3379 			 * used NLST, do what the user meant.
   3380 			 */
   3381 			/* XXX: nuke this support? */
   3382 			if (dirname[0] == '-' && *dirlist == NULL &&
   3383 			    transflag == 0) {
   3384 				char *argv[] = { INTERNAL_LS, "", NULL };
   3385 
   3386 				argv[1] = dirname;
   3387 				retrieve(argv, dirname);
   3388 				goto cleanup_send_file_list;
   3389 			}
   3390 			perror_reply(450, whichf);
   3391 			goto cleanup_send_file_list;
   3392 		}
   3393 
   3394 		if (S_ISREG(st.st_mode)) {
   3395 			/*
   3396 			 * XXXRFC:
   3397 			 *	should we follow RFC959 and not work
   3398 			 *	for non directories?
   3399 			 */
   3400 			if (dout == NULL) {
   3401 				dout = dataconn("file list", (off_t)-1, "w");
   3402 				if (dout == NULL)
   3403 					goto cleanup_send_file_list;
   3404 				transflag = 1;
   3405 			}
   3406 			cprintf(dout, "%s%s\n", dirname,
   3407 			    type == TYPE_A ? "\r" : "");
   3408 			continue;
   3409 		} else if (!S_ISDIR(st.st_mode))
   3410 			continue;
   3411 
   3412 		if (dirname[strlen(dirname) - 1] == '/')
   3413 			trailingslash++;
   3414 
   3415 		if ((dirp = opendir(dirname)) == NULL)
   3416 			continue;
   3417 
   3418 		while ((dir = readdir(dirp)) != NULL) {
   3419 			char nbuf[MAXPATHLEN];
   3420 
   3421 			if (urgflag && handleoobcmd())
   3422 				goto cleanup_send_file_list;
   3423 
   3424 			if (ISDOTDIR(dir->d_name) || ISDOTDOTDIR(dir->d_name))
   3425 				continue;
   3426 
   3427 			(void)snprintf(nbuf, sizeof(nbuf), "%s%s%s", dirname,
   3428 			    trailingslash ? "" : "/", dir->d_name);
   3429 
   3430 			/*
   3431 			 * We have to do a stat to ensure it's
   3432 			 * not a directory or special file.
   3433 			 */
   3434 			/*
   3435 			 * XXXRFC:
   3436 			 *	should we follow RFC959 and filter out
   3437 			 *	non files ?   lukem - NO!, or not until
   3438 			 *	our ftp client uses MLS{T,D} for completion.
   3439 			 */
   3440 			if (simple || (stat(nbuf, &st) == 0 &&
   3441 			    S_ISREG(st.st_mode))) {
   3442 				if (dout == NULL) {
   3443 					dout = dataconn("file list", (off_t)-1,
   3444 						"w");
   3445 					if (dout == NULL)
   3446 						goto cleanup_send_file_list;
   3447 					transflag = 1;
   3448 				}
   3449 				p = nbuf;
   3450 				if (nbuf[0] == '.' && nbuf[1] == '/')
   3451 					p = &nbuf[2];
   3452 				cprintf(dout, "%s%s\n", p,
   3453 				    type == TYPE_A ? "\r" : "");
   3454 			}
   3455 		}
   3456 		(void) closedir(dirp);
   3457 	}
   3458 
   3459 	if (dout == NULL)
   3460 		reply(450, "No files found.");
   3461 	else if (ferror(dout) != 0)
   3462 		perror_reply(451, "Data connection");
   3463 	else
   3464 		reply(226, "Transfer complete.");
   3465 
   3466  cleanup_send_file_list:
   3467 	closedataconn(dout);
   3468 	transflag = 0;
   3469 	urgflag = 0;
   3470 	total_xfers++;
   3471 	total_xfers_out++;
   3472 	if (notglob)
   3473 		free(notglob);
   3474 	if (freeglob)
   3475 		globfree(&gl);
   3476 }
   3477 
   3478 char *
   3479 conffilename(const char *s)
   3480 {
   3481 	static char filename[MAXPATHLEN];
   3482 
   3483 	if (*s == '/')
   3484 		strlcpy(filename, s, sizeof(filename));
   3485 	else
   3486 		(void)snprintf(filename, sizeof(filename), "%s/%s", confdir ,s);
   3487 	return (filename);
   3488 }
   3489 
   3490 /*
   3491  * logxfer --
   3492  *	if logging > 1, then based on the arguments, syslog a message:
   3493  *	 if bytes != -1		"<command> <file1> = <bytes> bytes"
   3494  *	 else if file2 != NULL	"<command> <file1> <file2>"
   3495  *	 else			"<command> <file1>"
   3496  *	if elapsed != NULL, append "in xxx.yyy seconds"
   3497  *	if error != NULL, append ": " + error
   3498  *
   3499  *	if doxferlog != 0, bytes != -1, and command is "get", "put",
   3500  *	or "append", syslog and/or write a wu-ftpd style xferlog entry
   3501  */
   3502 void
   3503 logxfer(const char *command, off_t bytes, const char *file1, const char *file2,
   3504     const struct timeval *elapsed, const char *error)
   3505 {
   3506 	char		 buf[MAXPATHLEN * 2 + 100];
   3507 	char		 realfile1[MAXPATHLEN], realfile2[MAXPATHLEN];
   3508 	const char	*r1, *r2;
   3509 	char		 direction;
   3510 	size_t		 len;
   3511 	time_t		 now;
   3512 
   3513 	if (logging <=1 && !doxferlog)
   3514 		return;
   3515 
   3516 	r1 = r2 = NULL;
   3517 	if ((r1 = realpath(file1, realfile1)) == NULL)
   3518 		r1 = file1;
   3519 	if (file2 != NULL)
   3520 		if ((r2 = realpath(file2, realfile2)) == NULL)
   3521 			r2 = file2;
   3522 
   3523 		/*
   3524 		 * syslog command
   3525 		 */
   3526 	if (logging > 1) {
   3527 		len = snprintf(buf, sizeof(buf), "%s %s", command, r1);
   3528 		if (bytes != (off_t)-1)
   3529 			len += snprintf(buf + len, sizeof(buf) - len,
   3530 			    " = " LLF " byte%s", (LLT) bytes, PLURAL(bytes));
   3531 		else if (r2 != NULL)
   3532 			len += snprintf(buf + len, sizeof(buf) - len,
   3533 			    " %s", r2);
   3534 		if (elapsed != NULL)
   3535 			len += snprintf(buf + len, sizeof(buf) - len,
   3536 			    " in %ld.%.03d seconds", elapsed->tv_sec,
   3537 			    (int)(elapsed->tv_usec / 1000));
   3538 		if (error != NULL)
   3539 			len += snprintf(buf + len, sizeof(buf) - len,
   3540 			    ": %s", error);
   3541 		syslog(LOG_INFO, "%s", buf);
   3542 	}
   3543 
   3544 		/*
   3545 		 * syslog wu-ftpd style log entry, prefixed with "xferlog: "
   3546 		 */
   3547 	if (!doxferlog || bytes == -1)
   3548 		return;
   3549 
   3550 	if (strcmp(command, "get") == 0)
   3551 		direction = 'o';
   3552 	else if (strcmp(command, "put") == 0 || strcmp(command, "append") == 0)
   3553 		direction = 'i';
   3554 	else
   3555 		return;
   3556 
   3557 	time(&now);
   3558 	len = snprintf(buf, sizeof(buf),
   3559 	    "%.24s %ld %s " LLF " %s %c %s %c %c %s FTP 0 * %c\n",
   3560 
   3561 /*
   3562  * XXX: wu-ftpd puts ' (send)' or ' (recv)' in the syslog message, and removes
   3563  *	the full date.  This may be problematic for accurate log parsing,
   3564  *	given that syslog messages don't contain the full date.
   3565  */
   3566 	    ctime(&now),
   3567 	    elapsed == NULL ? 0 : elapsed->tv_sec + (elapsed->tv_usec > 0),
   3568 	    remotehost,
   3569 	    (LLT) bytes,
   3570 	    r1,
   3571 	    type == TYPE_A ? 'a' : 'b',
   3572 	    "_",		/* XXX: take conversions into account? */
   3573 	    direction,
   3574 
   3575 	    curclass.type == CLASS_GUEST ?  'a' :
   3576 	    curclass.type == CLASS_CHROOT ? 'g' :
   3577 	    curclass.type == CLASS_REAL ?   'r' : '?',
   3578 
   3579 	    curclass.type == CLASS_GUEST ? pw->pw_passwd : pw->pw_name,
   3580 	    error != NULL ? 'i' : 'c'
   3581 	    );
   3582 
   3583 	if ((doxferlog & 2) && xferlogfd != -1)
   3584 		write(xferlogfd, buf, len);
   3585 	if ((doxferlog & 1)) {
   3586 		buf[len-1] = '\n';	/* strip \n from syslog message */
   3587 		syslog(LOG_INFO, "xferlog: %s", buf);
   3588 	}
   3589 }
   3590 
   3591 /*
   3592  * Log the resource usage.
   3593  *
   3594  * XXX: more resource usage to logging?
   3595  */
   3596 void
   3597 logrusage(const struct rusage *rusage_before,
   3598     const struct rusage *rusage_after)
   3599 {
   3600 	struct timeval usrtime, systime;
   3601 
   3602 	if (logging <= 1)
   3603 		return;
   3604 
   3605 	timersub(&rusage_after->ru_utime, &rusage_before->ru_utime, &usrtime);
   3606 	timersub(&rusage_after->ru_stime, &rusage_before->ru_stime, &systime);
   3607 	syslog(LOG_INFO, "%ld.%.03du %ld.%.03ds %ld+%ldio %ldpf+%ldw",
   3608 	    usrtime.tv_sec, (int)(usrtime.tv_usec / 1000),
   3609 	    systime.tv_sec, (int)(systime.tv_usec / 1000),
   3610 	    rusage_after->ru_inblock - rusage_before->ru_inblock,
   3611 	    rusage_after->ru_oublock - rusage_before->ru_oublock,
   3612 	    rusage_after->ru_majflt - rusage_before->ru_majflt,
   3613 	    rusage_after->ru_nswap - rusage_before->ru_nswap);
   3614 }
   3615 
   3616 /*
   3617  * Determine if `password' is valid for user given in `pw'.
   3618  * Returns 2 if password expired, 1 if otherwise failed, 0 if ok
   3619  */
   3620 int
   3621 checkpassword(const struct passwd *pwent, const char *password)
   3622 {
   3623 	char	*orig, *new;
   3624 	time_t	 change, expire, now;
   3625 
   3626 	change = expire = 0;
   3627 	if (pwent == NULL)
   3628 		return 1;
   3629 
   3630 	time(&now);
   3631 	orig = pwent->pw_passwd;	/* save existing password */
   3632 	expire = pwent->pw_expire;
   3633 	change = (pwent->pw_change == _PASSWORD_CHGNOW)? now : pwent->pw_change;
   3634 
   3635 	if (orig[0] == '\0')		/* don't allow empty passwords */
   3636 		return 1;
   3637 
   3638 	new = crypt(password, orig);	/* encrypt given password */
   3639 	if (strcmp(new, orig) != 0)	/* compare */
   3640 		return 1;
   3641 
   3642 	if ((expire && now >= expire) || (change && now >= change))
   3643 		return 2;		/* check if expired */
   3644 
   3645 	return 0;			/* OK! */
   3646 }
   3647 
   3648 char *
   3649 ftpd_strdup(const char *s)
   3650 {
   3651 	char *new = strdup(s);
   3652 
   3653 	if (new == NULL)
   3654 		fatal("Local resource failure: malloc");
   3655 		/* NOTREACHED */
   3656 	return (new);
   3657 }
   3658 
   3659 /*
   3660  * As per fprintf(), but increment total_bytes and total_bytes_out,
   3661  * by the appropriate amount.
   3662  */
   3663 void
   3664 cprintf(FILE *fd, const char *fmt, ...)
   3665 {
   3666 	off_t b;
   3667 	va_list ap;
   3668 
   3669 	va_start(ap, fmt);
   3670 	b = vfprintf(fd, fmt, ap);
   3671 	va_end(ap);
   3672 	total_bytes += b;
   3673 	total_bytes_out += b;
   3674 }
   3675 
   3676 #ifdef USE_PAM
   3677 /*
   3678  * the following code is stolen from imap-uw PAM authentication module and
   3679  * login.c
   3680  */
   3681 typedef struct {
   3682 	const char *uname;	/* user name */
   3683 	int	    triedonce;	/* if non-zero, tried before */
   3684 } ftpd_cred_t;
   3685 
   3686 static int
   3687 auth_conv(int num_msg, const struct pam_message **msg,
   3688     struct pam_response **resp, void *appdata)
   3689 {
   3690 	int i;
   3691 	size_t n;
   3692 	ftpd_cred_t *cred = (ftpd_cred_t *) appdata;
   3693 	struct pam_response *myreply;
   3694 	char pbuf[FTP_BUFLEN];
   3695 
   3696 	if (num_msg <= 0 || num_msg > PAM_MAX_NUM_MSG)
   3697 		return (PAM_CONV_ERR);
   3698 	myreply = calloc(num_msg, sizeof *myreply);
   3699 	if (myreply == NULL)
   3700 		return PAM_BUF_ERR;
   3701 
   3702 	for (i = 0; i < num_msg; i++) {
   3703 		myreply[i].resp_retcode = 0;
   3704 		myreply[i].resp = NULL;
   3705 		switch (msg[i]->msg_style) {
   3706 		case PAM_PROMPT_ECHO_ON:	/* user */
   3707 			myreply[i].resp = ftpd_strdup(cred->uname);
   3708 			/* PAM frees resp. */
   3709 			break;
   3710 		case PAM_PROMPT_ECHO_OFF:	/* authtok (password) */
   3711 				/*
   3712 				 * Only send a single 331 reply and
   3713 				 * then expect a PASS.
   3714 				 */
   3715 			if (cred->triedonce) {
   3716 				syslog(LOG_ERR,
   3717 			"auth_conv: already performed PAM_PROMPT_ECHO_OFF");
   3718 				goto fail;
   3719 			}
   3720 			cred->triedonce++;
   3721 			if (msg[i]->msg[0] == '\0') {
   3722 				(void)strlcpy(pbuf, "password", sizeof(pbuf));
   3723 			} else {
   3724 					/* Uncapitalize msg */
   3725 				(void)strlcpy(pbuf, msg[i]->msg, sizeof(pbuf));
   3726 				if (isupper((unsigned char)pbuf[0]))
   3727 					pbuf[0] = tolower(
   3728 					    (unsigned char)pbuf[0]);
   3729 					/* Remove trailing ':' and whitespace */
   3730 				n = strlen(pbuf);
   3731 				while (n-- > 0) {
   3732 					if (isspace((unsigned char)pbuf[n]) ||
   3733 					    pbuf[n] == ':')
   3734 						pbuf[n] = '\0';
   3735 					else
   3736 						break;
   3737 				}
   3738 			}
   3739 				/* Send reply, wait for a response. */
   3740 			reply(331, "User %s accepted, provide %s.",
   3741 			    cred->uname, pbuf);
   3742 			(void) alarm(curclass.timeout);
   3743 			if (getline(pbuf, sizeof(pbuf)-1, stdin) == NULL) {
   3744 				reply(221, "You could at least say goodbye.");
   3745 				dologout(0);
   3746 			}
   3747 			(void) alarm(0);
   3748 				/* Ensure it is PASS */
   3749 			if (strncasecmp(pbuf, "PASS ", 5) != 0) {
   3750 			    syslog(LOG_ERR,
   3751 				"auth_conv: unexpected reply '%.4s'", pbuf);
   3752 			    /* XXX: should we do this reply(-530, ..) ? */
   3753 			    reply(-530, "Unexpected reply '%.4s'.", pbuf);
   3754 			    goto fail;
   3755 			}
   3756 				/* Strip CRLF from "PASS" reply */
   3757 			n = strlen(pbuf);
   3758 			while (--n >= 5 &&
   3759 			    (pbuf[n] == '\r' || pbuf[n] == '\n'))
   3760 			    pbuf[n] = '\0';
   3761 				/* Copy password into reply */
   3762 			myreply[i].resp = ftpd_strdup(pbuf+5);
   3763 				/* PAM frees resp. */
   3764 			break;
   3765 		case PAM_TEXT_INFO:
   3766 		case PAM_ERROR_MSG:
   3767 			break;
   3768 		default:			/* unknown message style */
   3769 			goto fail;
   3770 		}
   3771 	}
   3772 
   3773 	*resp = myreply;
   3774 	return PAM_SUCCESS;
   3775 
   3776  fail:
   3777 	free(myreply);
   3778 	*resp = NULL;
   3779 	return PAM_CONV_ERR;
   3780 }
   3781 
   3782 /*
   3783  * Attempt to authenticate the user using PAM.  Returns 0 if the user is
   3784  * authenticated, or 1 if not authenticated.  If some sort of PAM system
   3785  * error occurs (e.g., the "/etc/pam.conf" file is missing) then this
   3786  * function returns -1.  This can be used as an indication that we should
   3787  * fall back to a different authentication mechanism.
   3788  * pw maybe be updated to a new user if PAM_USER changes from curname.
   3789  */
   3790 static int
   3791 auth_pam(void)
   3792 {
   3793 	const char *tmpl_user;
   3794 	const void *item;
   3795 	int rval;
   3796 	int e;
   3797 	ftpd_cred_t auth_cred = { curname, 0 };
   3798 	struct pam_conv conv = { &auth_conv, &auth_cred };
   3799 
   3800 	e = pam_start("ftpd", curname, &conv, &pamh);
   3801 	if (e != PAM_SUCCESS) {
   3802 		/*
   3803 		 * In OpenPAM, it's OK to pass NULL to pam_strerror()
   3804 		 * if context creation has failed in the first place.
   3805 		 */
   3806 		syslog(LOG_ERR, "pam_start: %s", pam_strerror(NULL, e));
   3807 		return -1;
   3808 	}
   3809 
   3810 	e = pam_set_item(pamh, PAM_RHOST, remotehost);
   3811 	if (e != PAM_SUCCESS) {
   3812 		syslog(LOG_ERR, "pam_set_item(PAM_RHOST): %s",
   3813 			pam_strerror(pamh, e));
   3814 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
   3815 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
   3816 		}
   3817 		pamh = NULL;
   3818 		return -1;
   3819 	}
   3820 
   3821 	e = pam_set_item(pamh, PAM_SOCKADDR, &his_addr);
   3822 	if (e != PAM_SUCCESS) {
   3823 		syslog(LOG_ERR, "pam_set_item(PAM_SOCKADDR): %s",
   3824 			pam_strerror(pamh, e));
   3825 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
   3826 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
   3827 		}
   3828 		pamh = NULL;
   3829 		return -1;
   3830 	}
   3831 
   3832 	e = pam_authenticate(pamh, 0);
   3833 	if (ftpd_debug)
   3834 		syslog(LOG_DEBUG, "pam_authenticate: user '%s' returned %d",
   3835 		    curname, e);
   3836 	switch (e) {
   3837 	case PAM_SUCCESS:
   3838 		/*
   3839 		 * With PAM we support the concept of a "template"
   3840 		 * user.  The user enters a login name which is
   3841 		 * authenticated by PAM, usually via a remote service
   3842 		 * such as RADIUS or TACACS+.  If authentication
   3843 		 * succeeds, a different but related "template" name
   3844 		 * is used for setting the credentials, shell, and
   3845 		 * home directory.  The name the user enters need only
   3846 		 * exist on the remote authentication server, but the
   3847 		 * template name must be present in the local password
   3848 		 * database.
   3849 		 *
   3850 		 * This is supported by two various mechanisms in the
   3851 		 * individual modules.  However, from the application's
   3852 		 * point of view, the template user is always passed
   3853 		 * back as a changed value of the PAM_USER item.
   3854 		 */
   3855 		if ((e = pam_get_item(pamh, PAM_USER, &item)) ==
   3856 		    PAM_SUCCESS) {
   3857 			tmpl_user = (const char *) item;
   3858 			if (pw == NULL
   3859 			    || strcmp(pw->pw_name, tmpl_user) != 0) {
   3860 				pw = sgetpwnam(tmpl_user);
   3861 				if (ftpd_debug)
   3862 					syslog(LOG_DEBUG,
   3863 					    "auth_pam: PAM changed "
   3864 					    "user from '%s' to '%s'",
   3865 					    curname, pw->pw_name);
   3866 				(void)strlcpy(curname, pw->pw_name,
   3867 				    curname_len);
   3868 			}
   3869 		} else
   3870 			syslog(LOG_ERR, "Couldn't get PAM_USER: %s",
   3871 			    pam_strerror(pamh, e));
   3872 		rval = 0;
   3873 		break;
   3874 
   3875 	case PAM_AUTH_ERR:
   3876 	case PAM_USER_UNKNOWN:
   3877 	case PAM_MAXTRIES:
   3878 		rval = 1;
   3879 		break;
   3880 
   3881 	default:
   3882 		syslog(LOG_ERR, "pam_authenticate: %s", pam_strerror(pamh, e));
   3883 		rval = -1;
   3884 		break;
   3885 	}
   3886 
   3887 	if (rval == 0) {
   3888 		e = pam_acct_mgmt(pamh, 0);
   3889 		if (e != PAM_SUCCESS) {
   3890 			syslog(LOG_ERR, "pam_acct_mgmt: %s",
   3891 						pam_strerror(pamh, e));
   3892 			rval = 1;
   3893 		}
   3894 	}
   3895 
   3896 	if (rval != 0) {
   3897 		if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
   3898 			syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
   3899 		}
   3900 		pamh = NULL;
   3901 	}
   3902 	return rval;
   3903 }
   3904 
   3905 #endif /* USE_PAM */
   3906