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/* $NetBSD: rexec.c,v 1.16 2003/08/07 16:44:16 agc Exp $ */
/*
* 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/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
#if 0
static char sccsid[] = "@(#)rexec.c 8.1 (Berkeley) 6/4/93";
#else
__RCSID("$NetBSD: rexec.c,v 1.16 2003/08/07 16:44:16 agc Exp $");
#endif
#endif /* LIBC_SCCS and not lint */
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <assert.h>
#include <err.h>
#include <errno.h>
#include <netdb.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
int rexecoptions;
int ruserpass __P((const char *, char **, char **));
int rexec __P((char **, int, char *, char *, char *, int *));
int
rexec(ahost, rport, name, pass, cmd, fd2p)
char **ahost;
int rport;
char *name, *pass, *cmd;
int *fd2p;
{
struct sockaddr_in rsin, from;
socklen_t fromlen;
struct hostent *hp;
u_short port;
size_t len;
unsigned int timo = 1;
int s, s3;
char c;
_DIAGASSERT(ahost != NULL);
_DIAGASSERT(name != NULL);
_DIAGASSERT(pass != NULL);
_DIAGASSERT(cmd != NULL);
/* fd2p may be NULL */
hp = gethostbyname(*ahost);
if (hp == 0) {
warnx("Error resolving %s (%s)", *ahost, hstrerror(h_errno));
return -1;
}
*ahost = hp->h_name;
(void)ruserpass(hp->h_name, &name, &pass);
retry:
if ((s = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
warn("Cannot create socket");
return (-1);
}
rsin.sin_family = hp->h_addrtype;
rsin.sin_len = sizeof(rsin);
rsin.sin_port = rport;
/* Avoid data corruption from bogus DNS results */
if (hp->h_length > (int) sizeof(rsin.sin_addr))
len = sizeof(rsin.sin_addr);
else
len = hp->h_length;
memcpy(&rsin.sin_addr, hp->h_addr, len);
if (connect(s, (struct sockaddr *)(void *)&rsin, sizeof(rsin)) == -1) {
if (errno == ECONNREFUSED && timo <= 16) {
(void)close(s);
sleep(timo);
timo *= 2;
goto retry;
}
warn("Cannot connect to %s", hp->h_name);
return -1;
}
port = 0;
if (fd2p == 0) {
(void)write(s, "", 1);
} else {
char num[8];
int s2;
struct sockaddr_in sin2;
socklen_t sin2len;
s2 = socket(AF_INET, SOCK_STREAM, 0);
if (s2 == -1) {
warn("Error creating socket");
(void)close(s);
return -1;
}
listen(s2, 1);
sin2len = sizeof(sin2);
if (getsockname(s2, (struct sockaddr *)(void *)&sin2,
&sin2len) == -1 || sin2len != sizeof(sin2)) {
warn("Failed to get socket name");
(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);
fromlen = sizeof(from);
s3 = accept(s2, (struct sockaddr *)(void *)&from, &fromlen);
(void)close(s2);
if (s3 == -1) {
warn("Error accepting connection");
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, 1) != 1) {
warn("Error reading from %s", *ahost);
goto bad;
}
if (c != 0) {
while (read(s, &c, 1) == 1) {
(void) write(2, &c, 1);
if (c == '\n')
break;
}
goto bad;
}
return s;
bad:
if (port)
(void)close(*fd2p);
(void)close(s);
return -1;
}
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