1/*	$NetBSD: main.c,v 1.2 2017/01/28 21:31:44 christos Exp $	*/
2
3/*
4 * Copyright (c) 1997-2005 Kungliga Tekniska H��gskolan
5 * (Royal Institute of Technology, Stockholm, Sweden).
6 * All rights reserved.
7 *
8 * Portions Copyright (c) 2009 Apple Inc. All rights reserved.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 *
14 * 1. Redistributions of source code must retain the above copyright
15 *    notice, this list of conditions and the following disclaimer.
16 *
17 * 2. Redistributions in binary form must reproduce the above copyright
18 *    notice, this list of conditions and the following disclaimer in the
19 *    documentation and/or other materials provided with the distribution.
20 *
21 * 3. Neither the name of the Institute nor the names of its contributors
22 *    may be used to endorse or promote products derived from this software
23 *    without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * SUCH DAMAGE.
36 */
37
38#include "kdc_locl.h"
39#ifdef HAVE_UTIL_H
40#include <util.h>
41#endif
42
43#ifdef HAVE_CAPNG
44#include <cap-ng.h>
45#endif
46
47sig_atomic_t exit_flag = 0;
48
49int detach_from_console = -1;
50int daemon_child = -1;
51int do_bonjour = -1;
52
53static RETSIGTYPE
54sigchld(int sig)
55{
56}
57
58static RETSIGTYPE
59sigterm(int sig)
60{
61    exit_flag = sig;
62}
63
64/*
65 * Allow dropping root bit, since heimdal reopens the database all the
66 * time the database needs to be owned by the user you are switched
67 * too. A better solution is to split the kdc in to more processes and
68 * run the network facing part with very low privilege.
69 */
70
71static void
72switch_environment(void)
73{
74#ifdef HAVE_GETEUID
75    if ((runas_string || chroot_string) && geteuid() != 0)
76	errx(1, "no running as root, can't switch user/chroot");
77
78    if (chroot_string) {
79	if (chroot(chroot_string))
80	    err(1, "chroot(%s) failed", chroot_string);
81	if (chdir("/"))
82	    err(1, "chdir(/) after chroot failed");
83    }
84
85    if (runas_string) {
86	struct passwd *pw;
87
88	pw = getpwnam(runas_string);
89	if (pw == NULL)
90	    errx(1, "unknown user %s", runas_string);
91
92	if (initgroups(pw->pw_name, pw->pw_gid) < 0)
93	    err(1, "initgroups failed");
94
95#ifndef HAVE_CAPNG
96	if (setgid(pw->pw_gid) < 0)
97	    err(1, "setgid(%s) failed", runas_string);
98
99	if (setuid(pw->pw_uid) < 0)
100	    err(1, "setuid(%s)", runas_string);
101#else
102	capng_clear (CAPNG_EFFECTIVE | CAPNG_PERMITTED);
103	if (capng_updatev (CAPNG_ADD, CAPNG_EFFECTIVE | CAPNG_PERMITTED,
104	                   CAP_NET_BIND_SERVICE, CAP_SETPCAP, -1) < 0)
105	    err(1, "capng_updateev");
106
107	if (capng_change_id(pw->pw_uid, pw->pw_gid,
108	                    CAPNG_CLEAR_BOUNDING) < 0)
109	    err(1, "capng_change_id(%s)", runas_string);
110#endif
111    }
112#endif
113}
114
115int
116main(int argc, char **argv)
117{
118    krb5_error_code ret;
119    krb5_context context;
120    krb5_kdc_configuration *config;
121    int optidx = 0;
122
123    setprogname(argv[0]);
124
125    ret = krb5_init_context(&context);
126    if (ret == KRB5_CONFIG_BADFORMAT)
127	errx (1, "krb5_init_context failed to parse configuration file");
128    else if (ret)
129	errx (1, "krb5_init_context failed: %d", ret);
130
131    ret = krb5_kt_register(context, &hdb_get_kt_ops);
132    if (ret)
133	errx (1, "krb5_kt_register(HDB) failed: %d", ret);
134
135    config = configure(context, argc, argv, &optidx);
136
137#ifdef HAVE_SIGACTION
138    {
139	struct sigaction sa;
140
141	sa.sa_flags = 0;
142	sa.sa_handler = sigterm;
143	sigemptyset(&sa.sa_mask);
144
145	sigaction(SIGINT, &sa, NULL);
146	sigaction(SIGTERM, &sa, NULL);
147#ifdef SIGXCPU
148	sigaction(SIGXCPU, &sa, NULL);
149#endif
150
151#ifdef SIGCHLD
152	sa.sa_handler = sigchld;
153	sigaction(SIGCHLD, &sa, NULL);
154#endif
155
156	sa.sa_handler = SIG_IGN;
157#ifdef SIGPIPE
158	sigaction(SIGPIPE, &sa, NULL);
159#endif
160    }
161#else
162    signal(SIGINT, sigterm);
163    signal(SIGTERM, sigterm);
164#ifdef SIGCHLD
165    signal(SIGCHLD, sigchld);
166#endif
167#ifdef SIGXCPU
168    signal(SIGXCPU, sigterm);
169#endif
170#ifdef SIGPIPE
171    signal(SIGPIPE, SIG_IGN);
172#endif
173#endif
174    rk_pidfile(NULL);
175
176    switch_environment();
177
178    start_kdc(context, config, argv[0]);
179    krb5_free_context(context);
180    return 0;
181}
182