225d233deb
Now when tcp_wrapper is enabled by inetd -wW,
several accesses which should be permitted are refused only for IPv6,
if hostname is used to decide the host to be allowed.
IPv6 users will be just upset.
About security related concern.
-All extensions are wrapped by #ifdef INET6, so people can completely
disable the extension by recompile libwrap without INET6 option.
-Access via IPv6 is not enabled by default.
People need to enable IPv6 access by changing /etc/inetd.conf at first,
by adding tcp6 and/or tcp46 entries.
-The base of patches are from KAME package and are actually daily used
for more than a year in several Japanese IPv6 environments.
-Patches are reviewed by markm.
Approved by: jkh
Submitted by: Hajimu UMEMOTO <ume@mahoroba.org>
Reviewed by: markm
Obtained from: KAME project
137 lines
3.4 KiB
C
137 lines
3.4 KiB
C
/*
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* General front end for stream and datagram IP services. This program logs
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* the remote host name and then invokes the real daemon. For example,
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* install as /usr/etc/{tftpd,fingerd,telnetd,ftpd,rlogind,rshd,rexecd},
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* after saving the real daemons in the directory specified with the
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* REAL_DAEMON_DIR macro. This arrangement requires that the network daemons
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* are started by inetd or something similar. Connections and diagnostics
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* are logged through syslog(3).
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*
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* Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
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*
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* $FreeBSD$
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*/
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#ifndef lint
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static char sccsid[] = "@(#) tcpd.c 1.10 96/02/11 17:01:32";
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#endif
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/* System libraries. */
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#include <sys/types.h>
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#include <sys/param.h>
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#include <sys/stat.h>
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#include <sys/socket.h>
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#include <netinet/in.h>
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#include <stdio.h>
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#include <syslog.h>
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#include <string.h>
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#ifndef MAXPATHNAMELEN
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#define MAXPATHNAMELEN BUFSIZ
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#endif
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#ifndef STDIN_FILENO
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#define STDIN_FILENO 0
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#endif
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/* Local stuff. */
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#include "patchlevel.h"
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#include "tcpd.h"
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int allow_severity = SEVERITY; /* run-time adjustable */
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int deny_severity = LOG_WARNING; /* ditto */
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main(argc, argv)
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int argc;
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char **argv;
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{
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struct request_info request;
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char path[MAXPATHNAMELEN];
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/* Attempt to prevent the creation of world-writable files. */
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#ifdef DAEMON_UMASK
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umask(DAEMON_UMASK);
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#endif
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/*
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* If argv[0] is an absolute path name, ignore REAL_DAEMON_DIR, and strip
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* argv[0] to its basename.
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*/
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if (argv[0][0] == '/') {
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strcpy(path, argv[0]);
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argv[0] = strrchr(argv[0], '/') + 1;
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} else {
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sprintf(path, "%s/%s", REAL_DAEMON_DIR, argv[0]);
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}
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/*
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* Open a channel to the syslog daemon. Older versions of openlog()
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* require only two arguments.
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*/
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#ifdef LOG_MAIL
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(void) openlog(argv[0], LOG_PID, FACILITY);
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#else
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(void) openlog(argv[0], LOG_PID);
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#endif
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/*
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* Find out the endpoint addresses of this conversation. Host name
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* lookups and double checks will be done on demand.
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*/
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request_init(&request, RQ_DAEMON, argv[0], RQ_FILE, STDIN_FILENO, 0);
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fromhost(&request);
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/*
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* Optionally look up and double check the remote host name. Sites
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* concerned with security may choose to refuse connections from hosts
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* that pretend to have someone elses host name.
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*/
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#ifdef PARANOID
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if (STR_EQ(eval_hostname(request.client), paranoid))
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refuse(&request);
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#endif
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/*
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* The BSD rlogin and rsh daemons that came out after 4.3 BSD disallow
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* socket options at the IP level. They do so for a good reason.
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* Unfortunately, we cannot use this with SunOS 4.1.x because the
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* getsockopt() system call can panic the system.
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*/
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#ifdef KILL_IP_OPTIONS
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fix_options(&request);
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#endif
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/*
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* Check whether this host can access the service in argv[0]. The
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* access-control code invokes optional shell commands as specified in
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* the access-control tables.
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*/
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#ifdef HOSTS_ACCESS
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if (!hosts_access(&request))
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refuse(&request);
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#endif
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/* Report request and invoke the real daemon program. */
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#ifdef INET6
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syslog(allow_severity, "connect from %s (%s)",
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eval_client(&request), eval_hostaddr(request.client));
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#else
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syslog(allow_severity, "connect from %s", eval_client(&request));
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#endif
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closelog();
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(void) execv(path, argv);
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syslog(LOG_ERR, "error: cannot execute %s: %m", path);
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clean_exit(&request);
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/* NOTREACHED */
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}
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