/*
* Copyright (c) 1983, 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. 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
static const char copyright[] =
"@(#) Copyright (c) 1983, 1993\n\
The Regents of the University of California. All rights reserved.\n";
#endif /* not lint */
#ifndef lint
#if 0
static char sccsid[] = "@(#)rexecd.c 8.1 (Berkeley) 6/4/93";
#endif
static const char rcsid[] =
"$Id: rexecd.c,v 1.15 1997/11/26 07:29:04 charnier Exp $";
#endif /* not lint */
#include <sys/param.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <err.h>
#include <netdb.h>
#include <libutil.h>
#include <paths.h>
#include <pwd.h>
#include <signal.h>
#include <stdio.h>
#include <skey.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <unistd.h>
char username[MAXLOGNAME + 5 + 1] = "USER=";
char homedir[MAXPATHLEN + 5 + 1] = "HOME=";
char shell[MAXPATHLEN + 6 + 1] = "SHELL=";
char path[sizeof(_PATH_DEFPATH) + sizeof("PATH=")] = "PATH=";
char *envinit[] =
{homedir, shell, path, username, 0};
char **environ;
char remote[MAXHOSTNAMELEN + 1];
struct sockaddr_in asin = { AF_INET };
void doit __P((int, struct sockaddr_in *));
void getstr __P((char *, int, char *));
/*VARARGS1*/
void error __P(());
/*
* remote execute server:
* username\0
* password\0
* command\0
* data
*/
/*ARGSUSED*/
int
main(argc, argv)
int argc;
char **argv;
{
struct sockaddr_in from;
int fromlen;
struct hostent *hp;
openlog(argv[0], LOG_PID, LOG_AUTH);
fromlen = sizeof (from);
if (getpeername(0, (struct sockaddr *)&from, &fromlen) < 0)
err(1, "getpeername");
realhostname(remote, sizeof remote - 1, &from.sin_addr);
doit(0, &from);
return(0);
}
void
doit(f, fromp)
int f;
struct sockaddr_in *fromp;
{
FILE *fp;
char cmdbuf[NCARGS+1], *cp, *namep;
#ifdef SKEY
char user[16], pass[100];
#else /* SKEY */
char user[16], pass[16];
#endif /* SKEY */
struct passwd *pwd;
int s;
u_short port;
int pv[2], pid, ready, readfrom, cc;
char buf[BUFSIZ], sig;
int one = 1;
(void) signal(SIGINT, SIG_DFL);
(void) signal(SIGQUIT, SIG_DFL);
(void) signal(SIGTERM, SIG_DFL);
#ifdef DEBUG
{ int t = open(_PATH_TTY, 2);
if (t >= 0) {
ioctl(t, TIOCNOTTY, (char *)0);
(void) close(t);
}
}
#endif
dup2(f, 0);
dup2(f, 1);
dup2(f, 2);
(void) alarm(60);
port = 0;
for (;;) {
char c;
if (read(f, &c, 1) != 1)
exit(1);
if (c == 0)
break;
port = port * 10 + c - '0';
}
(void) alarm(0);
if (port != 0) {
s = socket(AF_INET, SOCK_STREAM, 0);
if (s < 0)
exit(1);
if (bind(s, (struct sockaddr *)&asin, sizeof (asin)) < 0)
exit(1);
(void) alarm(60);
fromp->sin_port = htons(port);
if (connect(s, (struct sockaddr *)fromp, sizeof (*fromp)) < 0)
exit(1);
(void) alarm(0);
}
getstr(user, sizeof(user), "username");
getstr(pass, sizeof(pass), "password");
getstr(cmdbuf, sizeof(cmdbuf), "command");
setpwent();
pwd = getpwnam(user);
if (pwd == NULL) {
error("Login incorrect.\n");
exit(1);
}
endpwent();
if (*pwd->pw_passwd != '\0') {
#ifdef SKEY
namep = skey_crypt(pass, pwd->pw_passwd, pwd,
skeyaccess(user, NULL, remote, NULL));
#else /* SKEY */
namep = crypt(pass, pwd->pw_passwd);
#endif /* SKEY */
if (strcmp(namep, pwd->pw_passwd)) {
syslog(LOG_ERR, "LOGIN FAILURE from %s, %s",
remote, user);
error("Login incorrect.\n");
exit(1);
}
}
if (pwd->pw_uid == 0 || *pwd->pw_passwd == '\0' ||
(pwd->pw_expire && time(NULL) >= pwd->pw_expire)) {
syslog(LOG_ERR, "%s LOGIN REFUSED from %s", user, remote);
error("Login incorrect.\n");
exit(1);
}
if ((fp = fopen(_PATH_FTPUSERS, "r")) != NULL) {
while (fgets(buf, sizeof(buf), fp) != NULL) {
if ((cp = index(buf, '\n')) != NULL)
*cp = '\0';
if (strcmp(buf, pwd->pw_name) == 0) {
syslog(LOG_ERR, "%s LOGIN REFUSED from %s",
user, remote);
error("Login incorrect.\n");
exit(1);
}
}
}
(void) fclose(fp);
syslog(LOG_INFO, "login from %s as %s", remote, user);
(void) write(2, "\0", 1);
if (port) {
(void) pipe(pv);
pid = fork();
if (pid == -1) {
error("Try again.\n");
exit(1);
}
if (pid) {
(void) close(0); (void) close(1); (void) close(2);
(void) close(f); (void) close(pv[1]);
readfrom = (1<<s) | (1<<pv[0]);
ioctl(pv[1], FIONBIO, (char *)&one);
/* should set s nbio! */
do {
ready = readfrom;
(void) select(16, (fd_set *)&ready,
(fd_set *)NULL, (fd_set *)NULL,
(struct timeval *)NULL);
if (ready & (1<<s)) {
if (read(s, &sig, 1) <= 0)
readfrom &= ~(1<<s);
else
killpg(pid, sig);
}
if (ready & (1<<pv[0])) {
cc = read(pv[0], buf, sizeof (buf));
if (cc <= 0) {
shutdown(s, 1+1);
readfrom &= ~(1<<pv[0]);
} else
(void) write(s, buf, cc);
}
} while (readfrom);
exit(0);
}
setpgrp(0, getpid());
(void) close(s); (void)close(pv[0]);
dup2(pv[1], 2);
}
if (*pwd->pw_shell == '\0')
pwd->pw_shell = _PATH_BSHELL;
if (f > 2)
(void) close(f);
if (setlogin(pwd->pw_name) < 0)
syslog(LOG_ERR, "setlogin() failed: %m");
(void) setgid((gid_t)pwd->pw_gid);
initgroups(pwd->pw_name, pwd->pw_gid);
(void) setuid((uid_t)pwd->pw_uid);
(void)strcat(path, _PATH_DEFPATH);
environ = envinit;
strncat(homedir, pwd->pw_dir, sizeof(homedir)-6);
strncat(shell, pwd->pw_shell, sizeof(shell)-7);
strncat(username, pwd->pw_name, sizeof(username)-6);
cp = strrchr(pwd->pw_shell, '/');
if (cp)
cp++;
else
cp = pwd->pw_shell;
if (chdir(pwd->pw_dir) < 0) {
error("No remote directory.\n");
exit(1);
}
execl(pwd->pw_shell, cp, "-c", cmdbuf, 0);
err(1, "%s", pwd->pw_shell);
}
/*VARARGS1*/
void
error(fmt, a1, a2, a3)
char *fmt;
int a1, a2, a3;
{
char buf[BUFSIZ];
buf[0] = 1;
(void) snprintf(buf+1, sizeof(buf) - 1, fmt, a1, a2, a3);
(void) write(2, buf, strlen(buf));
}
void
getstr(buf, cnt, err)
char *buf;
int cnt;
char *err;
{
char c;
do {
if (read(0, &c, 1) != 1)
exit(1);
*buf++ = c;
if (--cnt == 0) {
error("%s too long\n", err);
exit(1);
}
} while (c != 0);
}
