/*
 * Copyright (c) 1980, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <sys/types.h>
#include <sys/socket.h>

#include <netinet/in.h>

#include <stdio.h>
#include <netdb.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>

int	rexecoptions;

void ruserpass(const char *, char **, char **);

int
rexec(char **ahost, int rport, char *name, char *pass, char *cmd, int *fd2p)
{
	struct sockaddr_in sin, sin2, from;
	struct hostent *hp;
	unsigned timo = 1;
	u_short port;
	int s, s3;
	char c;

	hp = gethostbyname(*ahost);
	if (hp == 0) {
		herror(*ahost);
		return (-1);
	}
	*ahost = hp->h_name;
	ruserpass(hp->h_name, &name, &pass);
retry:
	s = socket(AF_INET, SOCK_STREAM, 0);
	if (s < 0) {
		perror("rexec: socket");
		return (-1);
	}
	sin.sin_family = hp->h_addrtype;
	sin.sin_len = sizeof(sin);
	sin.sin_port = rport;
	bcopy(hp->h_addr, &sin.sin_addr, (size_t)hp->h_length);
	if (connect(s, (struct sockaddr *)&sin, sizeof(sin)) < 0) {
		if (errno == ECONNREFUSED && timo <= 16) {
			(void) close(s);
			sleep(timo);
			timo *= 2;
			goto retry;
		}
		perror(hp->h_name);
		return (-1);
	}
	port = 0;
	if (fd2p == 0) {
		(void) write(s, "", (size_t)1);
	} else {
		char num[8];
		int s2, sin2len;
		
		s2 = socket(AF_INET, SOCK_STREAM, 0);
		if (s2 < 0) {
			(void) close(s);
			return (-1);
		}
		listen(s2, 1);
		sin2len = sizeof (sin2);
		if (getsockname(s2, (struct sockaddr *)&sin2, &sin2len) < 0 ||
		    sin2len != sizeof (sin2)) {
			perror("getsockname");
			(void) close(s2);
			goto bad;
		}
		port = ntohs((u_short)sin2.sin_port);
		(void) snprintf(num, sizeof num, "%u", port);
		(void) write(s, num, strlen(num)+1);
		{
			int len = sizeof (from);

			s3 = accept(s2, (struct sockaddr *)&from, &len);
			close(s2);
			if (s3 < 0) {
				perror("accept");
				port = 0;
				goto bad;
			}
		}
		*fd2p = s3;
	}
	(void) write(s, name, strlen(name) + 1);
	/* should public key encypt the password here */
	(void) write(s, pass, strlen(pass) + 1);
	(void) write(s, cmd, strlen(cmd) + 1);
	if (read(s, &c, (size_t)1) != 1) {
		perror(*ahost);
		goto bad;
	}
	if (c != 0) {
		while (read(s, &c, (size_t)1) == 1) {
			(void) write(2, &c, (size_t)1);
			if (c == '\n')
				break;
		}
		goto bad;
	}
	return (s);
bad:
	if (port)
		(void) close(*fd2p);
	(void) close(s);
	return (-1);
}
