File: [local] / src / usr.bin / rsh / Attic / rsh.c (download)
Revision 1.25, Tue Feb 19 19:39:39 2002 UTC (22 years, 3 months ago) by millert
Branch: MAIN
CVS Tags: OPENBSD_3_1_BASE, OPENBSD_3_1 Changes since 1.24: +2 -19 lines
We live in an ANSI C world. Remove lots of gratuitous #ifdef __STDC__ cruft.
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/* $OpenBSD: rsh.c,v 1.25 2002/02/19 19:39:39 millert Exp $ */
/*-
* Copyright (c) 1983, 1990 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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.
*/
#ifndef lint
char copyright[] =
"@(#) Copyright (c) 1983, 1990 The Regents of the University of California.\n\
All rights reserved.\n";
#endif /* not lint */
#ifndef lint
/*static char sccsid[] = "from: @(#)rsh.c 5.24 (Berkeley) 7/1/91";*/
static char rcsid[] = "$OpenBSD: rsh.c,v 1.25 2002/02/19 19:39:39 millert Exp $";
#endif /* not lint */
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <sys/file.h>
#include <netinet/in.h>
#include <netdb.h>
#include <pwd.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <stdarg.h>
#include "pathnames.h"
#ifdef KERBEROS
#include <des.h>
#include <kerberosIV/krb.h>
CREDENTIALS cred;
Key_schedule schedule;
int use_kerberos = 1, doencrypt;
char dst_realm_buf[REALM_SZ], *dest_realm;
void warning(const char *, ...);
void desrw_set_key(des_cblock *, des_key_schedule *);
int des_read(int, char *, int);
int des_write(int, char *, int);
int krcmd(char **, u_short, char *, char *, int *, char *);
int krcmd_mutual(char **, u_short, char *, char *, int *, char *,
CREDENTIALS *, Key_schedule);
#endif
void usage(void);
void talk(int, sigset_t *, int, int);
/*
* rsh - remote shell
*/
int rfd2;
int
main(argc, argv)
int argc;
char **argv;
{
extern char *optarg;
extern int optind;
struct passwd *pw;
struct servent *sp;
sigset_t mask, omask;
int argoff, asrsh, ch, dflag, nflag, one, pid = 0, rem, uid;
char *p;
char *args, *host, *user, *copyargs();
void sendsig();
argoff = asrsh = dflag = nflag = 0;
one = 1;
host = user = NULL;
/* if called as something other than "rsh", use it as the host name */
if ((p = strrchr(argv[0], '/')))
++p;
else
p = argv[0];
if (strcmp(p, "rsh"))
host = p;
else
asrsh = 1;
/* handle "rsh host flags" */
if (!host && argc > 2 && argv[1][0] != '-') {
host = argv[1];
argoff = 1;
}
#ifdef KERBEROS
#define OPTIONS "8KLdek:l:nwx"
#else
#define OPTIONS "8KLdel:nw"
#endif
while ((ch = getopt(argc - argoff, argv + argoff, OPTIONS)) != -1)
switch(ch) {
case 'K':
#ifdef KERBEROS
use_kerberos = 0;
#endif
break;
case 'L': /* -8Lew are ignored to allow rlogin aliases */
case 'e':
case 'w':
case '8':
break;
case 'd':
dflag = 1;
break;
case 'l':
user = optarg;
break;
#ifdef KERBEROS
case 'k':
dest_realm = dst_realm_buf;
strncpy(dest_realm, optarg, REALM_SZ);
break;
#endif
case 'n':
nflag = 1;
break;
#ifdef KERBEROS
case 'x':
doencrypt = 1;
desrw_set_key(&cred.session, &schedule);
break;
#endif
case '?':
default:
usage();
}
optind += argoff;
/* if haven't gotten a host yet, do so */
if (!host && !(host = argv[optind++]))
usage();
/* if no further arguments, must have been called as rlogin. */
if (!argv[optind]) {
if (asrsh)
*argv = "rlogin";
seteuid(getuid());
setuid(getuid());
execv(_PATH_RLOGIN, argv);
(void)fprintf(stderr, "rsh: can't exec %s.\n", _PATH_RLOGIN);
exit(1);
}
argc -= optind;
argv += optind;
if (geteuid()) {
(void)fprintf(stderr, "rsh: must be setuid root.\n");
exit(1);
}
if (!(pw = getpwuid(uid = getuid()))) {
(void)fprintf(stderr, "rsh: unknown user id.\n");
exit(1);
}
if (!user)
user = pw->pw_name;
#ifdef KERBEROS
/* -x turns off -n */
if (doencrypt)
nflag = 0;
#endif
args = copyargs(argv);
sp = NULL;
#ifdef KERBEROS
if (use_kerberos) {
sp = getservbyname((doencrypt ? "ekshell" : "kshell"), "tcp");
if (sp == NULL) {
use_kerberos = 0;
warning("can't get entry for %s/tcp service",
doencrypt ? "ekshell" : "kshell");
}
}
#endif
if (sp == NULL)
sp = getservbyname("shell", "tcp");
if (sp == NULL) {
(void)fprintf(stderr, "rsh: shell/tcp: unknown service.\n");
exit(1);
}
(void) unsetenv("RSH"); /* no tricks with rcmd(3) */
#ifdef KERBEROS
try_connect:
if (use_kerberos) {
rem = KSUCCESS;
errno = 0;
if (dest_realm == NULL)
dest_realm = krb_realmofhost(host);
if (doencrypt)
rem = krcmd_mutual(&host, sp->s_port, user, args,
&rfd2, dest_realm, &cred, schedule);
else
rem = krcmd(&host, sp->s_port, user, args, &rfd2,
dest_realm);
if (rem < 0) {
use_kerberos = 0;
sp = getservbyname("shell", "tcp");
if (sp == NULL) {
(void)fprintf(stderr,
"rsh: unknown service shell/tcp.\n");
exit(1);
}
if (errno == ECONNREFUSED)
warning("remote host doesn't support Kerberos");
if (errno == ENOENT)
warning("can't provide Kerberos auth data");
goto try_connect;
}
} else {
if (doencrypt) {
(void)fprintf(stderr,
"rsh: the -x flag requires Kerberos authentication.\n");
exit(1);
}
rem = rcmd_af(&host, sp->s_port, pw->pw_name, user, args,
&rfd2, PF_UNSPEC);
}
#else
rem = rcmd_af(&host, sp->s_port, pw->pw_name, user, args, &rfd2,
PF_UNSPEC);
#endif
if (rem < 0)
exit(1);
if (rfd2 < 0) {
(void)fprintf(stderr, "rsh: can't establish stderr.\n");
exit(1);
}
if (dflag) {
if (setsockopt(rem, SOL_SOCKET, SO_DEBUG, &one,
sizeof(one)) < 0)
(void)fprintf(stderr, "rsh: setsockopt: %s.\n",
strerror(errno));
if (setsockopt(rfd2, SOL_SOCKET, SO_DEBUG, &one,
sizeof(one)) < 0)
(void)fprintf(stderr, "rsh: setsockopt: %s.\n",
strerror(errno));
}
(void)seteuid(uid);
(void)setuid(uid);
sigemptyset(&mask);
sigaddset(&mask, SIGINT);
sigaddset(&mask, SIGQUIT);
sigaddset(&mask, SIGTERM);
sigprocmask(SIG_BLOCK, &mask, &omask);
if (signal(SIGINT, SIG_IGN) != SIG_IGN)
(void)signal(SIGINT, sendsig);
if (signal(SIGQUIT, SIG_IGN) != SIG_IGN)
(void)signal(SIGQUIT, sendsig);
if (signal(SIGTERM, SIG_IGN) != SIG_IGN)
(void)signal(SIGTERM, sendsig);
if (!nflag) {
pid = fork();
if (pid < 0) {
(void)fprintf(stderr,
"rsh: fork: %s.\n", strerror(errno));
exit(1);
}
}
#ifdef KERBEROS
if (!doencrypt)
#endif
{
(void)ioctl(rfd2, FIONBIO, &one);
(void)ioctl(rem, FIONBIO, &one);
}
talk(nflag, &omask, pid, rem);
if (!nflag)
(void)kill(pid, SIGKILL);
return 0;
}
void
talk(nflag, omask, pid, rem)
int nflag, pid;
sigset_t *omask;
int rem;
{
int cc, wc;
char *bp;
fd_set readfrom, ready, rembits;
char buf[BUFSIZ];
if (!nflag && pid == 0) {
(void)close(rfd2);
reread: errno = 0;
if ((cc = read(0, buf, sizeof buf)) <= 0)
goto done;
bp = buf;
rewrite: FD_ZERO(&rembits);
FD_SET(rem, &rembits);
if (select(rem + 1, 0, &rembits, 0, 0) < 0) {
if (errno != EINTR) {
(void)fprintf(stderr,
"rsh: select: %s.\n", strerror(errno));
exit(1);
}
goto rewrite;
}
if (!FD_ISSET(rem, &rembits))
goto rewrite;
#ifdef KERBEROS
if (doencrypt)
wc = des_write(rem, bp, cc);
else
#endif
wc = write(rem, bp, cc);
if (wc < 0) {
if (errno == EWOULDBLOCK)
goto rewrite;
goto done;
}
bp += wc;
cc -= wc;
if (cc == 0)
goto reread;
goto rewrite;
done:
(void)shutdown(rem, 1);
exit(0);
}
sigprocmask(SIG_SETMASK, omask, NULL);
FD_ZERO(&readfrom);
FD_SET(rfd2, &readfrom);
FD_SET(rem, &readfrom);
do {
FD_COPY(&readfrom, &ready);
if (select(MAX(rfd2, rem) + 1, &ready, 0, 0, 0) < 0) {
if (errno != EINTR) {
(void)fprintf(stderr,
"rsh: select: %s.\n", strerror(errno));
exit(1);
}
continue;
}
if (FD_ISSET(rfd2, &ready)) {
errno = 0;
#ifdef KERBEROS
if (doencrypt)
cc = des_read(rfd2, buf, sizeof buf);
else
#endif
cc = read(rfd2, buf, sizeof buf);
if (cc <= 0) {
if (errno != EWOULDBLOCK)
FD_CLR(rfd2, &readfrom);
} else
(void)write(2, buf, cc);
}
if (FD_ISSET(rem, &ready)) {
errno = 0;
#ifdef KERBEROS
if (doencrypt)
cc = des_read(rem, buf, sizeof buf);
else
#endif
cc = read(rem, buf, sizeof buf);
if (cc <= 0) {
if (errno != EWOULDBLOCK)
FD_CLR(rem, &readfrom);
} else
(void)write(1, buf, cc);
}
} while (FD_ISSET(rem, &readfrom) || FD_ISSET(rfd2, &readfrom));
}
void
sendsig(signo)
char signo;
{
int save_errno = errno;
#ifdef KERBEROS
if (doencrypt)
(void)des_write(rfd2, &signo, 1);
else
#endif
(void)write(rfd2, &signo, 1);
errno = save_errno;
}
#ifdef KERBEROS
/* VARARGS */
void
warning(const char *fmt, ...)
{
va_list ap;
char myrealm[REALM_SZ];
if (krb_get_lrealm(myrealm, 0) != KSUCCESS)
return;
(void)fprintf(stderr, "rsh: warning, using standard rsh: ");
va_start(ap, fmt);
vfprintf(stderr, fmt, ap);
va_end(ap);
(void)fprintf(stderr, ".\n");
}
#endif
char *
copyargs(argv)
char **argv;
{
int cc;
char **ap, *p;
char *args, *malloc();
cc = 0;
for (ap = argv; *ap; ++ap)
cc += strlen(*ap) + 1;
if (!(args = malloc((u_int)cc))) {
(void)fprintf(stderr, "rsh: %s.\n", strerror(ENOMEM));
exit(1);
}
for (p = args, ap = argv; *ap; ++ap) {
(void)strcpy(p, *ap);
for (p = strcpy(p, *ap); *p; ++p);
if (ap[1])
*p++ = ' ';
}
return(args);
}
void
usage(void)
{
(void)fprintf(stderr,
"usage: rsh [-nd%s]%s[-l login] host [command]\n",
#ifdef KERBEROS
"x", " [-k realm] ");
#else
"", " ");
#endif
exit(1);
}