tftpd.c revision 241848 
1/*
2 * Copyright (c) 1983, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *	This product includes software developed by the University of
16 *	California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#ifndef lint
35static const char copyright[] =
36"@(#) Copyright (c) 1983, 1993\n\
37	The Regents of the University of California.  All rights reserved.\n";
38#endif /* not lint */
39
40#ifndef lint
41#if 0
42static char sccsid[] = "@(#)tftpd.c	8.1 (Berkeley) 6/4/93";
43#endif
44#endif /* not lint */
45#include <sys/cdefs.h>
46__FBSDID("$FreeBSD: head/libexec/tftpd/tftpd.c 241848 2012-10-22 03:07:05Z eadler $");
47
48/*
49 * Trivial file transfer protocol server.
50 *
51 * This version includes many modifications by Jim Guyton
52 * <guyton@rand-unix>.
53 */
54
55#include <sys/param.h>
56#include <sys/ioctl.h>
57#include <sys/stat.h>
58#include <sys/socket.h>
59
60#include <netinet/in.h>
61#include <arpa/tftp.h>
62
63#include <ctype.h>
64#include <errno.h>
65#include <fcntl.h>
66#include <netdb.h>
67#include <pwd.h>
68#include <stdio.h>
69#include <stdlib.h>
70#include <string.h>
71#include <syslog.h>
72#include <tcpd.h>
73#include <unistd.h>
74
75#include "tftp-file.h"
76#include "tftp-io.h"
77#include "tftp-utils.h"
78#include "tftp-transfer.h"
79#include "tftp-options.h"
80
81static void	tftp_wrq(int peer, char *, ssize_t);
82static void	tftp_rrq(int peer, char *, ssize_t);
83
84/*
85 * Null-terminated directory prefix list for absolute pathname requests and
86 * search list for relative pathname requests.
87 *
88 * MAXDIRS should be at least as large as the number of arguments that
89 * inetd allows (currently 20).
90 */
91#define MAXDIRS	20
92static struct dirlist {
93	const char	*name;
94	int	len;
95} dirs[MAXDIRS+1];
96static int	suppress_naks;
97static int	logging;
98static int	ipchroot;
99static int	create_new = 0;
100static const char *newfile_format = "%Y%m%d";
101static int	increase_name = 0;
102static mode_t	mask = S_IWGRP | S_IWOTH;
103
104struct formats;
105static void	tftp_recvfile(int peer, const char *mode);
106static void	tftp_xmitfile(int peer, const char *mode);
107static int	validate_access(int peer, char **, int);
108static char	peername[NI_MAXHOST];
109
110static FILE *file;
111
112static struct formats {
113	const char	*f_mode;
114	int	f_convert;
115} formats[] = {
116	{ "netascii",	1 },
117	{ "octet",	0 },
118	{ NULL,		0 }
119};
120
121int
122main(int argc, char *argv[])
123{
124	struct tftphdr *tp;
125	int		peer;
126	socklen_t	peerlen, len;
127	ssize_t		n;
128	int		ch;
129	char		*chroot_dir = NULL;
130	struct passwd	*nobody;
131	const char	*chuser = "nobody";
132	char		recvbuffer[MAXPKTSIZE];
133	int		allow_ro = 1, allow_wo = 1;
134
135	tzset();			/* syslog in localtime */
136	acting_as_client = 0;
137
138	tftp_openlog("tftpd", LOG_PID | LOG_NDELAY, LOG_FTP);
139	while ((ch = getopt(argc, argv, "cCd:F:lnoOp:s:u:U:wW")) != -1) {
140		switch (ch) {
141		case 'c':
142			ipchroot = 1;
143			break;
144		case 'C':
145			ipchroot = 2;
146			break;
147		case 'd':
148			if (atoi(optarg) != 0)
149				debug += atoi(optarg);
150			else
151				debug |= debug_finds(optarg);
152			break;
153		case 'F':
154			newfile_format = optarg;
155			break;
156		case 'l':
157			logging = 1;
158			break;
159		case 'n':
160			suppress_naks = 1;
161			break;
162		case 'o':
163			options_rfc_enabled = 0;
164			break;
165		case 'O':
166			options_extra_enabled = 0;
167			break;
168		case 'p':
169			packetdroppercentage = atoi(optarg);
170			tftp_log(LOG_INFO,
171			    "Randomly dropping %d out of 100 packets",
172			    packetdroppercentage);
173			break;
174		case 's':
175			chroot_dir = optarg;
176			break;
177		case 'u':
178			chuser = optarg;
179			break;
180		case 'U':
181			mask = strtol(optarg, NULL, 0);
182			break;
183		case 'w':
184			create_new = 1;
185			break;
186		case 'W':
187			create_new = 1;
188			increase_name = 1;
189			break;
190		default:
191			tftp_log(LOG_WARNING,
192				"ignoring unknown option -%c", ch);
193		}
194	}
195	if (optind < argc) {
196		struct dirlist *dirp;
197
198		/* Get list of directory prefixes. Skip relative pathnames. */
199		for (dirp = dirs; optind < argc && dirp < &dirs[MAXDIRS];
200		     optind++) {
201			if (argv[optind][0] == '/') {
202				dirp->name = argv[optind];
203				dirp->len  = strlen(dirp->name);
204				dirp++;
205			}
206		}
207	}
208	else if (chroot_dir) {
209		dirs->name = "/";
210		dirs->len = 1;
211	}
212	if (ipchroot > 0 && chroot_dir == NULL) {
213		tftp_log(LOG_ERR, "-c requires -s");
214		exit(1);
215	}
216
217	umask(mask);
218
219	{
220		int on = 1;
221		if (ioctl(0, FIONBIO, &on) < 0) {
222			tftp_log(LOG_ERR, "ioctl(FIONBIO): %s", strerror(errno));
223			exit(1);
224		}
225	}
226
227	/* Find out who we are talking to and what we are going to do */
228	peerlen = sizeof(peer_sock);
229	n = recvfrom(0, recvbuffer, MAXPKTSIZE, 0,
230	    (struct sockaddr *)&peer_sock, &peerlen);
231	if (n < 0) {
232		tftp_log(LOG_ERR, "recvfrom: %s", strerror(errno));
233		exit(1);
234	}
235	getnameinfo((struct sockaddr *)&peer_sock, peer_sock.ss_len,
236	    peername, sizeof(peername), NULL, 0, NI_NUMERICHOST);
237
238	/*
239	 * Now that we have read the message out of the UDP
240	 * socket, we fork and exit.  Thus, inetd will go back
241	 * to listening to the tftp port, and the next request
242	 * to come in will start up a new instance of tftpd.
243	 *
244	 * We do this so that inetd can run tftpd in "wait" mode.
245	 * The problem with tftpd running in "nowait" mode is that
246	 * inetd may get one or more successful "selects" on the
247	 * tftp port before we do our receive, so more than one
248	 * instance of tftpd may be started up.  Worse, if tftpd
249	 * break before doing the above "recvfrom", inetd would
250	 * spawn endless instances, clogging the system.
251	 */
252	{
253		int i, pid;
254
255		for (i = 1; i < 20; i++) {
256		    pid = fork();
257		    if (pid < 0) {
258				sleep(i);
259				/*
260				 * flush out to most recently sent request.
261				 *
262				 * This may drop some request, but those
263				 * will be resent by the clients when
264				 * they timeout.  The positive effect of
265				 * this flush is to (try to) prevent more
266				 * than one tftpd being started up to service
267				 * a single request from a single client.
268				 */
269				peerlen = sizeof peer_sock;
270				i = recvfrom(0, recvbuffer, MAXPKTSIZE, 0,
271				    (struct sockaddr *)&peer_sock, &peerlen);
272				if (i > 0) {
273					n = i;
274				}
275		    } else {
276				break;
277		    }
278		}
279		if (pid < 0) {
280			tftp_log(LOG_ERR, "fork: %s", strerror(errno));
281			exit(1);
282		} else if (pid != 0) {
283			exit(0);
284		}
285	}
286
287	/*
288	 * See if the client is allowed to talk to me.
289	 * (This needs to be done before the chroot())
290	 */
291	{
292		struct request_info req;
293
294		request_init(&req, RQ_CLIENT_ADDR, peername, 0);
295		request_set(&req, RQ_DAEMON, "tftpd", 0);
296
297		if (hosts_access(&req) == 0) {
298			if (debug&DEBUG_ACCESS)
299				tftp_log(LOG_WARNING,
300				    "Access denied by 'tftpd' entry "
301				    "in /etc/hosts.allow");
302
303			/*
304			 * Full access might be disabled, but maybe the
305			 * client is allowed to do read-only access.
306			 */
307			request_set(&req, RQ_DAEMON, "tftpd-ro", 0);
308			allow_ro = hosts_access(&req);
309
310			request_set(&req, RQ_DAEMON, "tftpd-wo", 0);
311			allow_wo = hosts_access(&req);
312
313			if (allow_ro == 0 && allow_wo == 0) {
314				tftp_log(LOG_WARNING,
315				    "Unauthorized access from %s", peername);
316				exit(1);
317			}
318
319			if (debug&DEBUG_ACCESS) {
320				if (allow_ro)
321					tftp_log(LOG_WARNING,
322					    "But allowed readonly access "
323					    "via 'tftpd-ro' entry");
324				if (allow_wo)
325					tftp_log(LOG_WARNING,
326					    "But allowed writeonly access "
327					    "via 'tftpd-wo' entry");
328			}
329		} else
330			if (debug&DEBUG_ACCESS)
331				tftp_log(LOG_WARNING,
332				    "Full access allowed"
333				    "in /etc/hosts.allow");
334	}
335
336	/*
337	 * Since we exit here, we should do that only after the above
338	 * recvfrom to keep inetd from constantly forking should there
339	 * be a problem.  See the above comment about system clogging.
340	 */
341	if (chroot_dir) {
342		if (ipchroot > 0) {
343			char *tempchroot;
344			struct stat sb;
345			int statret;
346			struct sockaddr_storage ss;
347			char hbuf[NI_MAXHOST];
348
349			statret = -1;
350			memcpy(&ss, &peer_sock, peer_sock.ss_len);
351			unmappedaddr((struct sockaddr_in6 *)&ss);
352			getnameinfo((struct sockaddr *)&ss, ss.ss_len,
353				    hbuf, sizeof(hbuf), NULL, 0,
354				    NI_NUMERICHOST);
355			asprintf(&tempchroot, "%s/%s", chroot_dir, hbuf);
356			if (ipchroot == 2)
357				statret = stat(tempchroot, &sb);
358			if (ipchroot == 1 ||
359			    (statret == 0 && (sb.st_mode & S_IFDIR)))
360				chroot_dir = tempchroot;
361		}
362		/* Must get this before chroot because /etc might go away */
363		if ((nobody = getpwnam(chuser)) == NULL) {
364			tftp_log(LOG_ERR, "%s: no such user", chuser);
365			exit(1);
366		}
367		if (chroot(chroot_dir)) {
368			tftp_log(LOG_ERR, "chroot: %s: %s",
369			    chroot_dir, strerror(errno));
370			exit(1);
371		}
372		chdir("/");
373		setgroups(1, &nobody->pw_gid);
374		if (setuid(nobody->pw_uid) != 0) {
375			tftp_log(LOG_ERR, "setuid failed");
376			exit(1);
377		}
378	}
379
380	len = sizeof(me_sock);
381	if (getsockname(0, (struct sockaddr *)&me_sock, &len) == 0) {
382		switch (me_sock.ss_family) {
383		case AF_INET:
384			((struct sockaddr_in *)&me_sock)->sin_port = 0;
385			break;
386		case AF_INET6:
387			((struct sockaddr_in6 *)&me_sock)->sin6_port = 0;
388			break;
389		default:
390			/* unsupported */
391			break;
392		}
393	} else {
394		memset(&me_sock, 0, sizeof(me_sock));
395		me_sock.ss_family = peer_sock.ss_family;
396		me_sock.ss_len = peer_sock.ss_len;
397	}
398	close(0);
399	close(1);
400	peer = socket(peer_sock.ss_family, SOCK_DGRAM, 0);
401	if (peer < 0) {
402		tftp_log(LOG_ERR, "socket: %s", strerror(errno));
403		exit(1);
404	}
405	if (bind(peer, (struct sockaddr *)&me_sock, me_sock.ss_len) < 0) {
406		tftp_log(LOG_ERR, "bind: %s", strerror(errno));
407		exit(1);
408	}
409
410	tp = (struct tftphdr *)recvbuffer;
411	tp->th_opcode = ntohs(tp->th_opcode);
412	if (tp->th_opcode == RRQ) {
413		if (allow_ro)
414			tftp_rrq(peer, tp->th_stuff, n - 1);
415		else {
416			tftp_log(LOG_WARNING,
417			    "%s read access denied", peername);
418			exit(1);
419		}
420	}
421	if (tp->th_opcode == WRQ) {
422		if (allow_wo)
423			tftp_wrq(peer, tp->th_stuff, n - 1);
424		else {
425			tftp_log(LOG_WARNING,
426			    "%s write access denied", peername);
427			exit(1);
428		}
429	}
430	exit(1);
431}
432
433static void
434reduce_path(char *fn)
435{
436	char *slash, *ptr;
437
438	/* Reduce all "/+./" to "/" (just in case we've got "/./../" later */
439	while ((slash = strstr(fn, "/./")) != NULL) {
440		for (ptr = slash; ptr > fn && ptr[-1] == '/'; ptr--)
441			;
442		slash += 2;
443		while (*slash)
444			*++ptr = *++slash;
445	}
446
447	/* Now reduce all "/something/+../" to "/" */
448	while ((slash = strstr(fn, "/../")) != NULL) {
449		if (slash == fn)
450			break;
451		for (ptr = slash; ptr > fn && ptr[-1] == '/'; ptr--)
452			;
453		for (ptr--; ptr >= fn; ptr--)
454			if (*ptr == '/')
455				break;
456		if (ptr < fn)
457			break;
458		slash += 3;
459		while (*slash)
460			*++ptr = *++slash;
461	}
462}
463
464static char *
465parse_header(int peer, char *recvbuffer, ssize_t size,
466	char **filename, char **mode)
467{
468	char	*cp;
469	int	i;
470	struct formats *pf;
471
472	*mode = NULL;
473	cp = recvbuffer;
474
475	i = get_field(peer, recvbuffer, size);
476	if (i >= PATH_MAX) {
477		tftp_log(LOG_ERR, "Bad option - filename too long");
478		send_error(peer, EBADOP);
479		exit(1);
480	}
481	*filename = recvbuffer;
482	tftp_log(LOG_INFO, "Filename: '%s'", *filename);
483	cp += i;
484
485	i = get_field(peer, cp, size);
486	*mode = cp;
487	cp += i;
488
489	/* Find the file transfer mode */
490	for (cp = *mode; *cp; cp++)
491		if (isupper(*cp))
492			*cp = tolower(*cp);
493	for (pf = formats; pf->f_mode; pf++)
494		if (strcmp(pf->f_mode, *mode) == 0)
495			break;
496	if (pf->f_mode == NULL) {
497		tftp_log(LOG_ERR,
498		    "Bad option - Unknown transfer mode (%s)", *mode);
499		send_error(peer, EBADOP);
500		exit(1);
501	}
502	tftp_log(LOG_INFO, "Mode: '%s'", *mode);
503
504	return (cp + 1);
505}
506
507/*
508 * WRQ - receive a file from the client
509 */
510void
511tftp_wrq(int peer, char *recvbuffer, ssize_t size)
512{
513	char *cp;
514	int has_options = 0, ecode;
515	char *filename, *mode;
516	char fnbuf[PATH_MAX];
517
518	cp = parse_header(peer, recvbuffer, size, &filename, &mode);
519	size -= (cp - recvbuffer) + 1;
520
521	strcpy(fnbuf, filename);
522	reduce_path(fnbuf);
523	filename = fnbuf;
524
525	if (size > 0) {
526		if (options_rfc_enabled)
527			has_options = !parse_options(peer, cp, size);
528		else
529			tftp_log(LOG_INFO, "Options found but not enabled");
530	}
531
532	ecode = validate_access(peer, &filename, WRQ);
533	if (ecode == 0) {
534		if (has_options)
535			send_oack(peer);
536		else
537			send_ack(peer, 0);
538	}
539	if (logging) {
540		tftp_log(LOG_INFO, "%s: write request for %s: %s", peername,
541			    filename, errtomsg(ecode));
542	}
543
544	tftp_recvfile(peer, mode);
545	exit(0);
546}
547
548/*
549 * RRQ - send a file to the client
550 */
551void
552tftp_rrq(int peer, char *recvbuffer, ssize_t size)
553{
554	char *cp;
555	int has_options = 0, ecode;
556	char *filename, *mode;
557	char	fnbuf[PATH_MAX];
558
559	cp = parse_header(peer, recvbuffer, size, &filename, &mode);
560	size -= (cp - recvbuffer) + 1;
561
562	strcpy(fnbuf, filename);
563	reduce_path(fnbuf);
564	filename = fnbuf;
565
566	if (size > 0) {
567		if (options_rfc_enabled)
568			has_options = !parse_options(peer, cp, size);
569		else
570			tftp_log(LOG_INFO, "Options found but not enabled");
571	}
572
573	ecode = validate_access(peer, &filename, RRQ);
574	if (ecode == 0) {
575		if (has_options) {
576			int n;
577			char lrecvbuffer[MAXPKTSIZE];
578			struct tftphdr *rp = (struct tftphdr *)lrecvbuffer;
579
580			send_oack(peer);
581			n = receive_packet(peer, lrecvbuffer, MAXPKTSIZE,
582				NULL, timeoutpacket);
583			if (n < 0) {
584				if (debug&DEBUG_SIMPLE)
585					tftp_log(LOG_DEBUG, "Aborting: %s",
586					    rp_strerror(n));
587				return;
588			}
589			if (rp->th_opcode != ACK) {
590				if (debug&DEBUG_SIMPLE)
591					tftp_log(LOG_DEBUG,
592					    "Expected ACK, got %s on OACK",
593					    packettype(rp->th_opcode));
594				return;
595			}
596		}
597	}
598
599	if (logging)
600		tftp_log(LOG_INFO, "%s: read request for %s: %s", peername,
601			    filename, errtomsg(ecode));
602
603	if (ecode) {
604		/*
605		 * Avoid storms of naks to a RRQ broadcast for a relative
606		 * bootfile pathname from a diskless Sun.
607		 */
608		if (suppress_naks && *filename != '/' && ecode == ENOTFOUND)
609			exit(0);
610		send_error(peer, ecode);
611		exit(1);
612	}
613	tftp_xmitfile(peer, mode);
614}
615
616/*
617 * Find the next value for YYYYMMDD.nn when the file to be written should
618 * be unique. Due to the limitations of nn, we will fail if nn reaches 100.
619 * Besides, that is four updates per hour on a file, which is kind of
620 * execessive anyway.
621 */
622static int
623find_next_name(char *filename, int *fd)
624{
625	int i;
626	time_t tval;
627	size_t len;
628	struct tm lt;
629	char yyyymmdd[MAXPATHLEN];
630	char newname[MAXPATHLEN];
631
632	/* Create the YYYYMMDD part of the filename */
633	time(&tval);
634	lt = *localtime(&tval);
635	len = strftime(yyyymmdd, sizeof(yyyymmdd), newfile_format, &lt);
636	if (len == 0) {
637		syslog(LOG_WARNING,
638			"Filename suffix too long (%d characters maximum)",
639			MAXPATHLEN);
640		return (EACCESS);
641	}
642
643	/* Make sure the new filename is not too long */
644	if (strlen(filename) > MAXPATHLEN - len - 5) {
645		syslog(LOG_WARNING,
646			"Filename too long (%zd characters, %zd maximum)",
647			strlen(filename), MAXPATHLEN - len - 5);
648		return (EACCESS);
649	}
650
651	/* Find the first file which doesn't exist */
652	for (i = 0; i < 100; i++) {
653		sprintf(newname, "%s.%s.%02d", filename, yyyymmdd, i);
654		*fd = open(newname,
655		    O_WRONLY | O_CREAT | O_EXCL,
656		    S_IRUSR | S_IWUSR | S_IRGRP |
657		    S_IWGRP | S_IROTH | S_IWOTH);
658		if (*fd > 0)
659			return 0;
660	}
661
662	return (EEXIST);
663}
664
665/*
666 * Validate file access.  Since we
667 * have no uid or gid, for now require
668 * file to exist and be publicly
669 * readable/writable.
670 * If we were invoked with arguments
671 * from inetd then the file must also be
672 * in one of the given directory prefixes.
673 * Note also, full path name must be
674 * given as we have no login directory.
675 */
676int
677validate_access(int peer, char **filep, int mode)
678{
679	struct stat stbuf;
680	int	fd;
681	int	error;
682	struct dirlist *dirp;
683	static char pathname[MAXPATHLEN];
684	char *filename = *filep;
685
686	/*
687	 * Prevent tricksters from getting around the directory restrictions
688	 */
689	if (strstr(filename, "/../"))
690		return (EACCESS);
691
692	if (*filename == '/') {
693		/*
694		 * Allow the request if it's in one of the approved locations.
695		 * Special case: check the null prefix ("/") by looking
696		 * for length = 1 and relying on the arg. processing that
697		 * it's a /.
698		 */
699		for (dirp = dirs; dirp->name != NULL; dirp++) {
700			if (dirp->len == 1 ||
701			    (!strncmp(filename, dirp->name, dirp->len) &&
702			     filename[dirp->len] == '/'))
703				    break;
704		}
705		/* If directory list is empty, allow access to any file */
706		if (dirp->name == NULL && dirp != dirs)
707			return (EACCESS);
708		if (stat(filename, &stbuf) < 0)
709			return (errno == ENOENT ? ENOTFOUND : EACCESS);
710		if ((stbuf.st_mode & S_IFMT) != S_IFREG)
711			return (ENOTFOUND);
712		if (mode == RRQ) {
713			if ((stbuf.st_mode & S_IROTH) == 0)
714				return (EACCESS);
715		} else {
716			if ((stbuf.st_mode & S_IWOTH) == 0)
717				return (EACCESS);
718		}
719	} else {
720		int err;
721
722		/*
723		 * Relative file name: search the approved locations for it.
724		 * Don't allow write requests that avoid directory
725		 * restrictions.
726		 */
727
728		if (!strncmp(filename, "../", 3))
729			return (EACCESS);
730
731		/*
732		 * If the file exists in one of the directories and isn't
733		 * readable, continue looking. However, change the error code
734		 * to give an indication that the file exists.
735		 */
736		err = ENOTFOUND;
737		for (dirp = dirs; dirp->name != NULL; dirp++) {
738			snprintf(pathname, sizeof(pathname), "%s/%s",
739				dirp->name, filename);
740			if (stat(pathname, &stbuf) == 0 &&
741			    (stbuf.st_mode & S_IFMT) == S_IFREG) {
742				if ((stbuf.st_mode & S_IROTH) != 0) {
743					break;
744				}
745				err = EACCESS;
746			}
747		}
748		if (dirp->name != NULL)
749			*filep = filename = pathname;
750		else if (mode == RRQ)
751			return (err);
752	}
753
754	/*
755	 * This option is handled here because it (might) require(s) the
756	 * size of the file.
757	 */
758	option_tsize(peer, NULL, mode, &stbuf);
759
760	if (mode == RRQ)
761		fd = open(filename, O_RDONLY);
762	else {
763		if (create_new) {
764			if (increase_name) {
765				error = find_next_name(filename, &fd);
766				if (error > 0)
767					return (error + 100);
768			} else
769				fd = open(filename,
770				    O_WRONLY | O_TRUNC | O_CREAT,
771				    S_IRUSR | S_IWUSR | S_IRGRP |
772				    S_IWGRP | S_IROTH | S_IWOTH );
773		} else
774			fd = open(filename, O_WRONLY | O_TRUNC);
775	}
776	if (fd < 0)
777		return (errno + 100);
778	file = fdopen(fd, (mode == RRQ)? "r":"w");
779	if (file == NULL) {
780		close(fd);
781		return (errno + 100);
782	}
783	return (0);
784}
785
786static void
787tftp_xmitfile(int peer, const char *mode)
788{
789	uint16_t block;
790	time_t now;
791	struct tftp_stats ts;
792
793	now = time(NULL);
794	if (debug&DEBUG_SIMPLE)
795		tftp_log(LOG_DEBUG, "Transmitting file");
796
797	read_init(0, file, mode);
798	block = 1;
799	tftp_send(peer, &block, &ts);
800	read_close();
801	if (debug&DEBUG_SIMPLE)
802		tftp_log(LOG_INFO, "Sent %d bytes in %d seconds",
803		    ts.amount, time(NULL) - now);
804}
805
806static void
807tftp_recvfile(int peer, const char *mode)
808{
809	uint16_t block;
810	struct timeval now1, now2;
811	struct tftp_stats ts;
812
813	gettimeofday(&now1, NULL);
814	if (debug&DEBUG_SIMPLE)
815		tftp_log(LOG_DEBUG, "Receiving file");
816
817	write_init(0, file, mode);
818
819	block = 0;
820	tftp_receive(peer, &block, &ts, NULL, 0);
821
822	write_close();
823	gettimeofday(&now2, NULL);
824
825	if (debug&DEBUG_SIMPLE) {
826		double f;
827		if (now1.tv_usec > now2.tv_usec) {
828			now2.tv_usec += 1000000;
829			now2.tv_sec--;
830		}
831
832		f = now2.tv_sec - now1.tv_sec +
833		    (now2.tv_usec - now1.tv_usec) / 100000.0;
834		tftp_log(LOG_INFO,
835		    "Download of %d bytes in %d blocks completed after %0.1f seconds\n",
836		    ts.amount, block, f);
837	}
838
839	return;
840}
841