blob: ee313da55930a8b1b7401cf7bc3093d54a6a0ab9 [file] [log] [blame]
Damien Miller7acefbb2014-07-18 14:11:24 +10001/* $Id: platform.c,v 1.22 2014/07/18 04:11:26 djm Exp $ */
Damien Miller1b06dc32006-08-31 03:24:41 +10002
3/*
4 * Copyright (c) 2006 Darren Tucker. All rights reserved.
5 *
6 * Permission to use, copy, modify, and distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
9 *
10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17 */
18
Darren Tuckerd1ece6e2010-11-07 18:05:54 +110019#include "includes.h"
Darren Tuckerb12fe272010-11-05 14:47:01 +110020
21#include <sys/types.h>
Darren Tucker9283d8c2010-11-05 18:56:08 +110022
23#include <stdarg.h>
Darren Tuckerb12fe272010-11-05 14:47:01 +110024#include <unistd.h>
25
Darren Tucker9283d8c2010-11-05 18:56:08 +110026#include "log.h"
27#include "buffer.h"
Damien Miller7acefbb2014-07-18 14:11:24 +100028#include "misc.h"
Darren Tucker9283d8c2010-11-05 18:56:08 +110029#include "servconf.h"
Damien Miller81ad4b12011-01-11 17:02:23 +110030#include "key.h"
31#include "hostfile.h"
32#include "auth.h"
33#include "auth-pam.h"
Damien Miller1b06dc32006-08-31 03:24:41 +100034#include "platform.h"
35
36#include "openbsd-compat/openbsd-compat.h"
37
Darren Tucker728d8372010-11-05 13:00:05 +110038extern int use_privsep;
Darren Tucker9283d8c2010-11-05 18:56:08 +110039extern ServerOptions options;
Darren Tucker728d8372010-11-05 13:00:05 +110040
Damien Miller1b06dc32006-08-31 03:24:41 +100041void
Darren Tuckerc8802aa2009-12-08 13:39:48 +110042platform_pre_listen(void)
43{
44#ifdef LINUX_OOM_ADJUST
45 /* Adjust out-of-memory killer so listening process is not killed */
46 oom_adjust_setup();
47#endif
48}
49
50void
Damien Miller1b06dc32006-08-31 03:24:41 +100051platform_pre_fork(void)
52{
53#ifdef USE_SOLARIS_PROCESS_CONTRACTS
54 solaris_contract_pre_fork();
55#endif
56}
57
58void
Darren Tuckerf2bf36c2013-09-22 19:02:40 +100059platform_pre_restart(void)
60{
61#ifdef LINUX_OOM_ADJUST
62 oom_adjust_restore();
63#endif
64}
65
66void
Damien Miller1b06dc32006-08-31 03:24:41 +100067platform_post_fork_parent(pid_t child_pid)
68{
69#ifdef USE_SOLARIS_PROCESS_CONTRACTS
70 solaris_contract_post_fork_parent(child_pid);
71#endif
72}
73
74void
75platform_post_fork_child(void)
76{
77#ifdef USE_SOLARIS_PROCESS_CONTRACTS
78 solaris_contract_post_fork_child();
79#endif
Darren Tuckerc8802aa2009-12-08 13:39:48 +110080#ifdef LINUX_OOM_ADJUST
81 oom_adjust_restore();
82#endif
Damien Miller1b06dc32006-08-31 03:24:41 +100083}
Darren Tucker1bf35032009-12-21 10:49:21 +110084
Darren Tuckerb12fe272010-11-05 14:47:01 +110085/* return 1 if we are running with privilege to swap UIDs, 0 otherwise */
86int
87platform_privileged_uidswap(void)
88{
89#ifdef HAVE_CYGWIN
90 /* uid 0 is not special on Cygwin so always try */
91 return 1;
92#else
93 return (getuid() == 0 || geteuid() == 0);
94#endif
95}
96
Darren Tucker920612e2010-11-05 12:36:15 +110097/*
98 * This gets called before switching UIDs, and is called even when sshd is
99 * not running as root.
100 */
Darren Tucker97528352010-11-05 12:03:05 +1100101void
102platform_setusercontext(struct passwd *pw)
103{
Darren Tucker920612e2010-11-05 12:36:15 +1100104#ifdef WITH_SELINUX
105 /* Cache selinux status for later use */
106 (void)ssh_selinux_enabled();
107#endif
108
Darren Tucker97528352010-11-05 12:03:05 +1100109#ifdef USE_SOLARIS_PROJECTS
110 /* if solaris projects were detected, set the default now */
111 if (getuid() == 0 || geteuid() == 0)
112 solaris_set_default_project(pw);
113#endif
Darren Tucker44a97be2010-11-05 12:45:18 +1100114
115#if defined(HAVE_LOGIN_CAP) && defined (__bsdi__)
Darren Tuckerfd4d8aa2010-11-05 12:50:41 +1100116 if (getuid() == 0 || geteuid() == 0)
117 setpgid(0, 0);
Darren Tucker44a97be2010-11-05 12:45:18 +1100118# endif
Darren Tucker728d8372010-11-05 13:00:05 +1100119
120#if defined(HAVE_LOGIN_CAP) && defined(USE_PAM)
121 /*
122 * If we have both LOGIN_CAP and PAM, we want to establish creds
123 * before calling setusercontext (in session.c:do_setusercontext).
124 */
125 if (getuid() == 0 || geteuid() == 0) {
126 if (options.use_pam) {
127 do_pam_setcred(use_privsep);
128 }
129 }
130# endif /* USE_PAM */
Darren Tuckerd9957122010-11-24 10:09:13 +1100131
132#if !defined(HAVE_LOGIN_CAP) && defined(HAVE_GETLUID) && defined(HAVE_SETLUID)
133 if (getuid() == 0 || geteuid() == 0) {
134 /* Sets login uid for accounting */
135 if (getluid() == -1 && setluid(pw->pw_uid) == -1)
136 error("setluid: %s", strerror(errno));
137 }
138#endif
Darren Tucker97528352010-11-05 12:03:05 +1100139}
140
Darren Tucker920612e2010-11-05 12:36:15 +1100141/*
142 * This gets called after we've established the user's groups, and is only
143 * called if sshd is running as root.
144 */
145void
146platform_setusercontext_post_groups(struct passwd *pw)
147{
Darren Tuckercc124182010-11-05 13:32:52 +1100148#if !defined(HAVE_LOGIN_CAP) && defined(USE_PAM)
149 /*
150 * PAM credentials may take the form of supplementary groups.
151 * These will have been wiped by the above initgroups() call.
152 * Reestablish them here.
153 */
154 if (options.use_pam) {
155 do_pam_setcred(use_privsep);
156 }
157#endif /* USE_PAM */
158
Darren Tucker0b2ee642010-11-05 13:29:25 +1100159#if !defined(HAVE_LOGIN_CAP) && (defined(WITH_IRIX_PROJECT) || \
160 defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY))
161 irix_setusercontext(pw);
162#endif /* defined(WITH_IRIX_PROJECT) || defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY) */
163
Darren Tucker676b9122010-11-05 13:11:04 +1100164#ifdef _AIX
165 aix_usrinfo(pw);
166#endif /* _AIX */
167
Darren Tucker4db38072010-11-05 12:41:13 +1100168#ifdef HAVE_SETPCRED
169 /*
170 * If we have a chroot directory, we set all creds except real
171 * uid which we will need for chroot. If we don't have a
172 * chroot directory, we don't override anything.
173 */
174 {
175 char **creds = NULL, *chroot_creds[] =
176 { "REAL_USER=root", NULL };
177
178 if (options.chroot_directory != NULL &&
179 strcasecmp(options.chroot_directory, "none") != 0)
180 creds = chroot_creds;
181
182 if (setpcred(pw->pw_name, creds) == -1)
183 fatal("Failed to set process credentials");
184 }
185#endif /* HAVE_SETPCRED */
Darren Tucker920612e2010-11-05 12:36:15 +1100186#ifdef WITH_SELINUX
187 ssh_selinux_setup_exec_context(pw->pw_name);
188#endif
189}
190
Darren Tucker1bf35032009-12-21 10:49:21 +1100191char *
192platform_krb5_get_principal_name(const char *pw_name)
193{
194#ifdef USE_AIX_KRB_NAME
195 return aix_krb5_get_principal_name(pw_name);
196#else
197 return NULL;
198#endif
199}
Darren Tuckeraa97d132013-03-12 11:31:05 +1100200
201/*
202 * return 1 if the specified uid is a uid that may own a system directory
203 * otherwise 0.
204 */
205int
206platform_sys_dir_uid(uid_t uid)
207{
208 if (uid == 0)
209 return 1;
210#ifdef PLATFORM_SYS_DIR_UID
211 if (uid == PLATFORM_SYS_DIR_UID)
212 return 1;
213#endif
214 return 0;
215}