138 lines
3.5 KiB
C
138 lines
3.5 KiB
C
/*
|
|
* General front end for stream and datagram IP services. This program logs
|
|
* the remote host name and then invokes the real daemon. For example,
|
|
* install as /usr/etc/{tftpd,fingerd,telnetd,ftpd,rlogind,rshd,rexecd},
|
|
* after saving the real daemons in the directory specified with the
|
|
* REAL_DAEMON_DIR macro. This arrangement requires that the network daemons
|
|
* are started by inetd or something similar. Connections and diagnostics
|
|
* are logged through syslog(3).
|
|
*
|
|
* Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
|
|
*
|
|
* $FreeBSD$
|
|
*/
|
|
|
|
#ifndef lint
|
|
static char sccsid[] = "@(#) tcpd.c 1.10 96/02/11 17:01:32";
|
|
#endif
|
|
|
|
/* System libraries. */
|
|
|
|
#include <sys/types.h>
|
|
#include <sys/param.h>
|
|
#include <sys/stat.h>
|
|
#include <sys/socket.h>
|
|
#include <netinet/in.h>
|
|
#include <stdio.h>
|
|
#include <syslog.h>
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
|
|
#ifndef MAXPATHNAMELEN
|
|
#define MAXPATHNAMELEN BUFSIZ
|
|
#endif
|
|
|
|
#ifndef STDIN_FILENO
|
|
#define STDIN_FILENO 0
|
|
#endif
|
|
|
|
/* Local stuff. */
|
|
|
|
#include "patchlevel.h"
|
|
#include "tcpd.h"
|
|
|
|
int allow_severity = SEVERITY; /* run-time adjustable */
|
|
int deny_severity = LOG_WARNING; /* ditto */
|
|
|
|
main(argc, argv)
|
|
int argc;
|
|
char **argv;
|
|
{
|
|
struct request_info request;
|
|
char path[MAXPATHNAMELEN];
|
|
|
|
/* Attempt to prevent the creation of world-writable files. */
|
|
|
|
#ifdef DAEMON_UMASK
|
|
umask(DAEMON_UMASK);
|
|
#endif
|
|
|
|
/*
|
|
* If argv[0] is an absolute path name, ignore REAL_DAEMON_DIR, and strip
|
|
* argv[0] to its basename.
|
|
*/
|
|
|
|
if (argv[0][0] == '/') {
|
|
strlcpy(path, argv[0], sizeof(path));
|
|
argv[0] = strrchr(argv[0], '/') + 1;
|
|
} else {
|
|
snprintf(path, sizeof(path), "%s/%s", REAL_DAEMON_DIR, argv[0]);
|
|
}
|
|
|
|
/*
|
|
* Open a channel to the syslog daemon. Older versions of openlog()
|
|
* require only two arguments.
|
|
*/
|
|
|
|
#ifdef LOG_MAIL
|
|
(void) openlog(argv[0], LOG_PID, FACILITY);
|
|
#else
|
|
(void) openlog(argv[0], LOG_PID);
|
|
#endif
|
|
|
|
/*
|
|
* Find out the endpoint addresses of this conversation. Host name
|
|
* lookups and double checks will be done on demand.
|
|
*/
|
|
|
|
request_init(&request, RQ_DAEMON, argv[0], RQ_FILE, STDIN_FILENO, 0);
|
|
fromhost(&request);
|
|
|
|
/*
|
|
* Optionally look up and double check the remote host name. Sites
|
|
* concerned with security may choose to refuse connections from hosts
|
|
* that pretend to have someone elses host name.
|
|
*/
|
|
|
|
#ifdef PARANOID
|
|
if (STR_EQ(eval_hostname(request.client), paranoid))
|
|
refuse(&request);
|
|
#endif
|
|
|
|
/*
|
|
* The BSD rlogin and rsh daemons that came out after 4.3 BSD disallow
|
|
* socket options at the IP level. They do so for a good reason.
|
|
* Unfortunately, we cannot use this with SunOS 4.1.x because the
|
|
* getsockopt() system call can panic the system.
|
|
*/
|
|
|
|
#ifdef KILL_IP_OPTIONS
|
|
fix_options(&request);
|
|
#endif
|
|
|
|
/*
|
|
* Check whether this host can access the service in argv[0]. The
|
|
* access-control code invokes optional shell commands as specified in
|
|
* the access-control tables.
|
|
*/
|
|
|
|
#ifdef HOSTS_ACCESS
|
|
if (!hosts_access(&request))
|
|
refuse(&request);
|
|
#endif
|
|
|
|
/* Report request and invoke the real daemon program. */
|
|
|
|
#ifdef INET6
|
|
syslog(allow_severity, "connect from %s (%s)",
|
|
eval_client(&request), eval_hostaddr(request.client));
|
|
#else
|
|
syslog(allow_severity, "connect from %s", eval_client(&request));
|
|
#endif
|
|
closelog();
|
|
(void) execv(path, argv);
|
|
syslog(LOG_ERR, "error: cannot execute %s: %m", path);
|
|
clean_exit(&request);
|
|
/* NOTREACHED */
|
|
}
|