rcp.c revision 178825
1/*
2 * Copyright (c) 1983, 1990, 1992, 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#include "rcp_locl.h"
35#include <getarg.h>
36
37#define RSH_PROGRAM "rsh"
38
39struct  passwd *pwd;
40uid_t	userid;
41int     errs, remin, remout;
42int     pflag, iamremote, iamrecursive, targetshouldbedirectory;
43int     doencrypt, noencrypt;
44int     usebroken, usekrb4, usekrb5, forwardtkt;
45char    *port;
46int     eflag = 0;
47
48#define	CMDNEEDS	64
49char cmd[CMDNEEDS];		/* must hold "rcp -r -p -d\0" */
50
51int	 response (void);
52void	 rsource (char *, struct stat *);
53void	 sink (int, char *[]);
54void	 source (int, char *[]);
55void	 tolocal (int, char *[]);
56void	 toremote (char *, int, char *[]);
57
58int      do_cmd(char *host, char *remuser, char *cmd, int *fdin, int *fdout);
59
60static int fflag, tflag;
61
62static int version_flag, help_flag;
63
64struct getargs args[] = {
65    { NULL,	'4', arg_flag,		&usekrb4,	"use Kerberos 4 authentication" },
66    { NULL,	'5', arg_flag,		&usekrb5,	"use Kerberos 5 authentication" },
67    { NULL,	'F', arg_flag,		&forwardtkt,	"forward credentials" },
68    { NULL,	'K', arg_flag,		&usebroken,	"use BSD authentication" },
69    { NULL,	'P', arg_string,	&port,		"non-default port", "port" },
70    { NULL,	'p', arg_flag,		&pflag,	"preserve file permissions" },
71    { NULL,	'r', arg_flag,		&iamrecursive,	"recursive mode" },
72    { NULL,	'x', arg_flag,		&doencrypt,	"use encryption" },
73    { NULL,	'z', arg_flag,		&noencrypt,	"don't encrypt" },
74    { NULL,	'd', arg_flag,		&targetshouldbedirectory },
75    { NULL,	'e', arg_flag,		&eflag, 	"passed to rsh" },
76    { NULL,	'f', arg_flag,		&fflag },
77    { NULL,	't', arg_flag,		&tflag },
78    { "version", 0,  arg_flag,		&version_flag },
79    { "help",	 0,  arg_flag,		&help_flag }
80};
81
82static void
83usage (int ret)
84{
85    arg_printusage (args,
86		    sizeof(args) / sizeof(args[0]),
87		    NULL,
88		    "file1 file2|file... directory");
89    exit (ret);
90}
91
92int
93main(int argc, char **argv)
94{
95	char *targ;
96	int optind = 0;
97
98	setprogname(argv[0]);
99	if (getarg (args, sizeof(args) / sizeof(args[0]), argc, argv,
100		    &optind))
101	    usage (1);
102	if(help_flag)
103	    usage(0);
104	if (version_flag) {
105	    print_version (NULL);
106	    return 0;
107	}
108
109	iamremote = (fflag || tflag);
110
111	argc -= optind;
112	argv += optind;
113
114	if ((pwd = getpwuid(userid = getuid())) == NULL)
115		errx(1, "unknown user %d", (int)userid);
116
117	remin = STDIN_FILENO;		/* XXX */
118	remout = STDOUT_FILENO;
119
120	if (fflag) {			/* Follow "protocol", send data. */
121		response();
122		if (setuid(userid) < 0)
123			errx(1, "setuid failed");
124		source(argc, argv);
125		exit(errs);
126	}
127
128	if (tflag) {			/* Receive data. */
129		if (setuid(userid) < 0)
130			errx(1, "setuid failed");
131		sink(argc, argv);
132		exit(errs);
133	}
134
135	if (argc < 2)
136	    usage(1);
137	if (argc > 2)
138		targetshouldbedirectory = 1;
139
140	remin = remout = -1;
141	/* Command to be executed on remote system using "rsh". */
142	snprintf(cmd, sizeof(cmd),
143		 "rcp%s%s%s", iamrecursive ? " -r" : "",
144		 pflag ? " -p" : "", targetshouldbedirectory ? " -d" : "");
145
146	signal(SIGPIPE, lostconn);
147
148	if ((targ = colon(argv[argc - 1])))	/* Dest is remote host. */
149		toremote(targ, argc, argv);
150	else {
151		tolocal(argc, argv);		/* Dest is local host. */
152		if (targetshouldbedirectory)
153			verifydir(argv[argc - 1]);
154	}
155	exit(errs);
156}
157
158void
159toremote(char *targ, int argc, char **argv)
160{
161	int i;
162	char *bp, *host, *src, *suser, *thost, *tuser;
163
164	*targ++ = 0;
165	if (*targ == 0)
166		targ = ".";
167
168	if ((thost = strchr(argv[argc - 1], '@'))) {
169		/* user@host */
170		*thost++ = 0;
171		tuser = argv[argc - 1];
172		if (*tuser == '\0')
173			tuser = NULL;
174		else if (!okname(tuser))
175			exit(1);
176	} else {
177		thost = argv[argc - 1];
178		tuser = NULL;
179	}
180
181	for (i = 0; i < argc - 1; i++) {
182		src = colon(argv[i]);
183		if (src) {			/* remote to remote */
184			int ret;
185			*src++ = 0;
186			if (*src == 0)
187				src = ".";
188			host = strchr(argv[i], '@');
189			if (host) {
190				*host++ = '\0';
191				suser = argv[i];
192				if (*suser == '\0')
193					suser = pwd->pw_name;
194				else if (!okname(suser))
195					continue;
196				ret = asprintf(&bp,
197				    "%s%s %s -l %s -n %s %s '%s%s%s:%s'",
198					 _PATH_RSH, eflag ? " -e" : "",
199					 host, suser, cmd, src,
200				    tuser ? tuser : "", tuser ? "@" : "",
201				    thost, targ);
202			} else {
203				ret = asprintf(&bp,
204					 "exec %s%s %s -n %s %s '%s%s%s:%s'",
205					 _PATH_RSH, eflag ? " -e" : "",
206					 argv[i], cmd, src,
207					 tuser ? tuser : "", tuser ? "@" : "",
208					 thost, targ);
209			}
210			if (ret == -1)
211				err (1, "malloc");
212			susystem(bp, userid);
213			free(bp);
214		} else {			/* local to remote */
215			if (remin == -1) {
216				if (asprintf(&bp, "%s -t %s", cmd, targ) == -1)
217					err (1, "malloc");
218				host = thost;
219
220				if (do_cmd(host, tuser, bp, &remin, &remout) < 0)
221					exit(1);
222
223				if (response() < 0)
224					exit(1);
225				free(bp);
226				if (setuid(userid) < 0)
227					errx(1, "setuid failed");
228			}
229			source(1, argv+i);
230		}
231	}
232}
233
234void
235tolocal(int argc, char **argv)
236{
237	int i;
238	char *bp, *host, *src, *suser;
239
240	for (i = 0; i < argc - 1; i++) {
241		int ret;
242
243		if (!(src = colon(argv[i]))) {		/* Local to local. */
244			ret = asprintf(&bp, "exec %s%s%s %s %s", _PATH_CP,
245			    iamrecursive ? " -PR" : "", pflag ? " -p" : "",
246			    argv[i], argv[argc - 1]);
247			if (ret == -1)
248				err (1, "malloc");
249			if (susystem(bp, userid))
250				++errs;
251			free(bp);
252			continue;
253		}
254		*src++ = 0;
255		if (*src == 0)
256			src = ".";
257		if ((host = strchr(argv[i], '@')) == NULL) {
258			host = argv[i];
259			suser = pwd->pw_name;
260		} else {
261			*host++ = 0;
262			suser = argv[i];
263			if (*suser == '\0')
264				suser = pwd->pw_name;
265			else if (!okname(suser))
266				continue;
267		}
268		ret = asprintf(&bp, "%s -f %s", cmd, src);
269		if (ret == -1)
270			err (1, "malloc");
271		if (do_cmd(host, suser, bp, &remin, &remout) < 0) {
272			free(bp);
273			++errs;
274			continue;
275		}
276		free(bp);
277		sink(1, argv + argc - 1);
278		if (seteuid(0) < 0)
279			exit(1);
280		close(remin);
281		remin = remout = -1;
282	}
283}
284
285void
286source(int argc, char **argv)
287{
288	struct stat stb;
289	static BUF buffer;
290	BUF *bp;
291	off_t i;
292	int amt, fd, haderr, indx, result;
293	char *last, *name, buf[BUFSIZ];
294
295	for (indx = 0; indx < argc; ++indx) {
296                name = argv[indx];
297		if ((fd = open(name, O_RDONLY, 0)) < 0)
298			goto syserr;
299		if (fstat(fd, &stb)) {
300syserr:			run_err("%s: %s", name, strerror(errno));
301			goto next;
302		}
303		switch (stb.st_mode & S_IFMT) {
304		case S_IFREG:
305			break;
306		case S_IFDIR:
307			if (iamrecursive) {
308				rsource(name, &stb);
309				goto next;
310			}
311			/* FALLTHROUGH */
312		default:
313			run_err("%s: not a regular file", name);
314			goto next;
315		}
316		if ((last = strrchr(name, '/')) == NULL)
317			last = name;
318		else
319			++last;
320		if (pflag) {
321			/*
322			 * Make it compatible with possible future
323			 * versions expecting microseconds.
324			 */
325			snprintf(buf, sizeof(buf), "T%ld 0 %ld 0\n",
326			    (long)stb.st_mtime,
327			    (long)stb.st_atime);
328			write(remout, buf, strlen(buf));
329			if (response() < 0)
330				goto next;
331		}
332#undef MODEMASK
333#define	MODEMASK	(S_ISUID|S_ISGID|S_ISVTX|S_IRWXU|S_IRWXG|S_IRWXO)
334		snprintf(buf, sizeof(buf), "C%04o %lu %s\n",
335			 stb.st_mode & MODEMASK,
336			 (unsigned long)stb.st_size,
337			 last);
338		write(remout, buf, strlen(buf));
339		if (response() < 0)
340			goto next;
341		if ((bp = allocbuf(&buffer, fd, BUFSIZ)) == NULL) {
342next:			close(fd);
343			continue;
344		}
345
346		/* Keep writing after an error so that we stay sync'd up. */
347		for (haderr = i = 0; i < stb.st_size; i += bp->cnt) {
348			amt = bp->cnt;
349			if (i + amt > stb.st_size)
350				amt = stb.st_size - i;
351			if (!haderr) {
352				result = read(fd, bp->buf, amt);
353				if (result != amt)
354					haderr = result >= 0 ? EIO : errno;
355			}
356			if (haderr)
357				write(remout, bp->buf, amt);
358			else {
359				result = write(remout, bp->buf, amt);
360				if (result != amt)
361					haderr = result >= 0 ? EIO : errno;
362			}
363		}
364		if (close(fd) && !haderr)
365			haderr = errno;
366		if (!haderr)
367			write(remout, "", 1);
368		else
369			run_err("%s: %s", name, strerror(haderr));
370		response();
371	}
372}
373
374void
375rsource(char *name, struct stat *statp)
376{
377	DIR *dirp;
378	struct dirent *dp;
379	char *last, *vect[1], path[MAXPATHLEN];
380
381	if (!(dirp = opendir(name))) {
382		run_err("%s: %s", name, strerror(errno));
383		return;
384	}
385	last = strrchr(name, '/');
386	if (last == 0)
387		last = name;
388	else
389		last++;
390	if (pflag) {
391		snprintf(path, sizeof(path), "T%ld 0 %ld 0\n",
392		    (long)statp->st_mtime,
393		    (long)statp->st_atime);
394		write(remout, path, strlen(path));
395		if (response() < 0) {
396			closedir(dirp);
397			return;
398		}
399	}
400	snprintf(path, sizeof(path),
401	    "D%04o %d %s\n", statp->st_mode & MODEMASK, 0, last);
402	write(remout, path, strlen(path));
403	if (response() < 0) {
404		closedir(dirp);
405		return;
406	}
407	while ((dp = readdir(dirp))) {
408		if (dp->d_ino == 0)
409			continue;
410		if (!strcmp(dp->d_name, ".") || !strcmp(dp->d_name, ".."))
411			continue;
412		if (strlen(name) + 1 + strlen(dp->d_name) >= MAXPATHLEN - 1) {
413			run_err("%s/%s: name too long", name, dp->d_name);
414			continue;
415		}
416		snprintf(path, sizeof(path), "%s/%s", name, dp->d_name);
417		vect[0] = path;
418		source(1, vect);
419	}
420	closedir(dirp);
421	write(remout, "E\n", 2);
422	response();
423}
424
425void
426sink(int argc, char **argv)
427{
428	static BUF buffer;
429	struct stat stb;
430	struct timeval tv[2];
431	enum { YES, NO, DISPLAYED } wrerr;
432	BUF *bp;
433	off_t i, j, size;
434	int amt, count, exists, first, mask, mode, ofd, omode;
435	int setimes, targisdir, wrerrno = 0;
436	char ch, *cp, *np, *targ, *why, *vect[1], buf[BUFSIZ];
437
438#define	atime	tv[0]
439#define	mtime	tv[1]
440#define	SCREWUP(str)	{ why = str; goto screwup; }
441
442	setimes = targisdir = 0;
443	mask = umask(0);
444	if (!pflag)
445		umask(mask);
446	if (argc != 1) {
447		run_err("ambiguous target");
448		exit(1);
449	}
450	targ = *argv;
451	if (targetshouldbedirectory)
452		verifydir(targ);
453	write(remout, "", 1);
454	if (stat(targ, &stb) == 0 && S_ISDIR(stb.st_mode))
455		targisdir = 1;
456	for (first = 1;; first = 0) {
457		cp = buf;
458		if (read(remin, cp, 1) <= 0)
459			return;
460		if (*cp++ == '\n')
461			SCREWUP("unexpected <newline>");
462		do {
463			if (read(remin, &ch, sizeof(ch)) != sizeof(ch))
464				SCREWUP("lost connection");
465			*cp++ = ch;
466		} while (cp < &buf[BUFSIZ - 1] && ch != '\n');
467		*cp = 0;
468
469		if (buf[0] == '\01' || buf[0] == '\02') {
470			if (iamremote == 0)
471				write(STDERR_FILENO,
472				    buf + 1, strlen(buf + 1));
473			if (buf[0] == '\02')
474				exit(1);
475			++errs;
476			continue;
477		}
478		if (buf[0] == 'E') {
479			write(remout, "", 1);
480			return;
481		}
482
483		if (ch == '\n')
484			*--cp = 0;
485
486		cp = buf;
487		if (*cp == 'T') {
488			setimes++;
489			cp++;
490			mtime.tv_sec = strtol(cp, &cp, 10);
491			if (!cp || *cp++ != ' ')
492				SCREWUP("mtime.sec not delimited");
493			mtime.tv_usec = strtol(cp, &cp, 10);
494			if (!cp || *cp++ != ' ')
495				SCREWUP("mtime.usec not delimited");
496			atime.tv_sec = strtol(cp, &cp, 10);
497			if (!cp || *cp++ != ' ')
498				SCREWUP("atime.sec not delimited");
499			atime.tv_usec = strtol(cp, &cp, 10);
500			if (!cp || *cp++ != '\0')
501				SCREWUP("atime.usec not delimited");
502			write(remout, "", 1);
503			continue;
504		}
505		if (*cp != 'C' && *cp != 'D') {
506			/*
507			 * Check for the case "rcp remote:foo\* local:bar".
508			 * In this case, the line "No match." can be returned
509			 * by the shell before the rcp command on the remote is
510			 * executed so the ^Aerror_message convention isn't
511			 * followed.
512			 */
513			if (first) {
514				run_err("%s", cp);
515				exit(1);
516			}
517			SCREWUP("expected control record");
518		}
519		mode = 0;
520		for (++cp; cp < buf + 5; cp++) {
521			if (*cp < '0' || *cp > '7')
522				SCREWUP("bad mode");
523			mode = (mode << 3) | (*cp - '0');
524		}
525		if (*cp++ != ' ')
526			SCREWUP("mode not delimited");
527
528		for (size = 0; isdigit((unsigned char)*cp);)
529			size = size * 10 + (*cp++ - '0');
530		if (*cp++ != ' ')
531			SCREWUP("size not delimited");
532		if (targisdir) {
533			static char *namebuf;
534			static int cursize;
535			size_t need;
536
537			need = strlen(targ) + strlen(cp) + 250;
538			if (need > cursize) {
539				if (!(namebuf = malloc(need)))
540					run_err("%s", strerror(errno));
541			}
542			snprintf(namebuf, need, "%s%s%s", targ,
543			    *targ ? "/" : "", cp);
544			np = namebuf;
545		} else
546			np = targ;
547		exists = stat(np, &stb) == 0;
548		if (buf[0] == 'D') {
549			int mod_flag = pflag;
550			if (exists) {
551				if (!S_ISDIR(stb.st_mode)) {
552					errno = ENOTDIR;
553					goto bad;
554				}
555				if (pflag)
556					chmod(np, mode);
557			} else {
558				/* Handle copying from a read-only directory */
559				mod_flag = 1;
560				if (mkdir(np, mode | S_IRWXU) < 0)
561					goto bad;
562			}
563			vect[0] = np;
564			sink(1, vect);
565			if (setimes) {
566				setimes = 0;
567				if (utimes(np, tv) < 0)
568				    run_err("%s: set times: %s",
569					np, strerror(errno));
570			}
571			if (mod_flag)
572				chmod(np, mode);
573			continue;
574		}
575		omode = mode;
576		mode |= S_IWRITE;
577		if ((ofd = open(np, O_WRONLY|O_CREAT, mode)) < 0) {
578bad:			run_err("%s: %s", np, strerror(errno));
579			continue;
580		}
581		write(remout, "", 1);
582		if ((bp = allocbuf(&buffer, ofd, BUFSIZ)) == NULL) {
583			close(ofd);
584			continue;
585		}
586		cp = bp->buf;
587		wrerr = NO;
588		for (count = i = 0; i < size; i += BUFSIZ) {
589			amt = BUFSIZ;
590			if (i + amt > size)
591				amt = size - i;
592			count += amt;
593			if((j = net_read(remin, cp, amt)) != amt) {
594			    run_err("%s", j ? strerror(errno) :
595				    "dropped connection");
596			    exit(1);
597			}
598			amt -= j;
599			cp += j;
600			if (count == bp->cnt) {
601				/* Keep reading so we stay sync'd up. */
602				if (wrerr == NO) {
603					j = write(ofd, bp->buf, count);
604					if (j != count) {
605						wrerr = YES;
606						wrerrno = j >= 0 ? EIO : errno;
607					}
608				}
609				count = 0;
610				cp = bp->buf;
611			}
612		}
613		if (count != 0 && wrerr == NO &&
614		    (j = write(ofd, bp->buf, count)) != count) {
615			wrerr = YES;
616			wrerrno = j >= 0 ? EIO : errno;
617		}
618		if (ftruncate(ofd, size)) {
619			run_err("%s: truncate: %s", np, strerror(errno));
620			wrerr = DISPLAYED;
621		}
622		if (pflag) {
623			if (exists || omode != mode)
624				if (fchmod(ofd, omode))
625					run_err("%s: set mode: %s",
626					    np, strerror(errno));
627		} else {
628			if (!exists && omode != mode)
629				if (fchmod(ofd, omode & ~mask))
630					run_err("%s: set mode: %s",
631					    np, strerror(errno));
632		}
633		close(ofd);
634		response();
635		if (setimes && wrerr == NO) {
636			setimes = 0;
637			if (utimes(np, tv) < 0) {
638				run_err("%s: set times: %s",
639				    np, strerror(errno));
640				wrerr = DISPLAYED;
641			}
642		}
643		switch(wrerr) {
644		case YES:
645			run_err("%s: %s", np, strerror(wrerrno));
646			break;
647		case NO:
648			write(remout, "", 1);
649			break;
650		case DISPLAYED:
651			break;
652		}
653	}
654screwup:
655	run_err("protocol error: %s", why);
656	exit(1);
657}
658
659int
660response(void)
661{
662	char ch, *cp, resp, rbuf[BUFSIZ];
663
664	if (read(remin, &resp, sizeof(resp)) != sizeof(resp))
665		lostconn(0);
666
667	cp = rbuf;
668	switch(resp) {
669	case 0:				/* ok */
670		return (0);
671	default:
672		*cp++ = resp;
673		/* FALLTHROUGH */
674	case 1:				/* error, followed by error msg */
675	case 2:				/* fatal error, "" */
676		do {
677			if (read(remin, &ch, sizeof(ch)) != sizeof(ch))
678				lostconn(0);
679			*cp++ = ch;
680		} while (cp < &rbuf[BUFSIZ] && ch != '\n');
681
682		if (!iamremote)
683			write(STDERR_FILENO, rbuf, cp - rbuf);
684		++errs;
685		if (resp == 1)
686			return (-1);
687		exit(1);
688	}
689	/* NOTREACHED */
690}
691
692#include <stdarg.h>
693
694void
695run_err(const char *fmt, ...)
696{
697	static FILE *fp;
698	va_list ap;
699
700	++errs;
701	if (fp == NULL && !(fp = fdopen(remout, "w")))
702		return;
703	va_start(ap, fmt);
704	fprintf(fp, "%c", 0x01);
705	fprintf(fp, "rcp: ");
706	vfprintf(fp, fmt, ap);
707	fprintf(fp, "\n");
708	fflush(fp);
709	va_end(ap);
710
711	if (!iamremote) {
712	    va_start(ap, fmt);
713	    vwarnx(fmt, ap);
714	    va_end(ap);
715	}
716}
717
718/*
719 * This function executes the given command as the specified user on the
720 * given host.  This returns < 0 if execution fails, and >= 0 otherwise. This
721 * assigns the input and output file descriptors on success.
722 *
723 * If it cannot create necessary pipes it exits with error message.
724 */
725
726int
727do_cmd(char *host, char *remuser, char *cmd, int *fdin, int *fdout)
728{
729	int pin[2], pout[2], reserved[2];
730
731	/*
732	 * Reserve two descriptors so that the real pipes won't get
733	 * descriptors 0 and 1 because that will screw up dup2 below.
734	 */
735	pipe(reserved);
736
737	/* Create a socket pair for communicating with rsh. */
738	if (pipe(pin) < 0) {
739		perror("pipe");
740		exit(255);
741	}
742	if (pipe(pout) < 0) {
743		perror("pipe");
744		exit(255);
745	}
746
747	/* Free the reserved descriptors. */
748	close(reserved[0]);
749	close(reserved[1]);
750
751	/* For a child to execute the command on the remote host using rsh. */
752	if (fork() == 0) {
753		char *args[100];
754		unsigned int i;
755
756		/* Child. */
757		close(pin[1]);
758		close(pout[0]);
759		dup2(pin[0], 0);
760		dup2(pout[1], 1);
761		close(pin[0]);
762		close(pout[1]);
763
764		i = 0;
765		args[i++] = RSH_PROGRAM;
766		if (usekrb4)
767			args[i++] = "-4";
768		if (usekrb5)
769			args[i++] = "-5";
770		if (usebroken)
771			args[i++] = "-K";
772		if (doencrypt)
773			args[i++] = "-x";
774		if (forwardtkt)
775			args[i++] = "-F";
776		if (noencrypt)
777			args[i++] = "-z";
778		if (port != NULL) {
779			args[i++] = "-p";
780			args[i++] = port;
781		}
782		if (eflag)
783		    args[i++] = "-e";
784		if (remuser != NULL) {
785			args[i++] = "-l";
786			args[i++] = remuser;
787		}
788		args[i++] = host;
789		args[i++] = cmd;
790		args[i++] = NULL;
791
792		execvp(RSH_PROGRAM, args);
793		perror(RSH_PROGRAM);
794		exit(1);
795	}
796	/* Parent.  Close the other side, and return the local side. */
797	close(pin[0]);
798	*fdout = pin[1];
799	close(pout[1]);
800	*fdin = pout[0];
801	return 0;
802}
803