1 /* $NetBSD: main.c,v 1.2 2017/01/28 21:31:44 christos Exp $ */
2
3 /*
4 * Copyright (c) 1997-2005 Kungliga Tekniska Högskolan
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
47 sig_atomic_t exit_flag = 0;
48
49 int detach_from_console = -1;
50 int daemon_child = -1;
51 int do_bonjour = -1;
52
53 static RETSIGTYPE
sigchld(int sig)54 sigchld(int sig)
55 {
56 }
57
58 static RETSIGTYPE
sigterm(int sig)59 sigterm(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
71 static void
switch_environment(void)72 switch_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
115 int
main(int argc,char ** argv)116 main(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