File: platform.c

package info (click to toggle)
openssh 1:6.6p1-4~bpo70+1
  • links: PTS, VCS
  • area: main
  • in suites: wheezy-backports
  • size: 11,944 kB
  • sloc: ansic: 82,376; sh: 9,860; makefile: 857; awk: 339; perl: 53; python: 37; csh: 1
file content (198 lines) | stat: -rw-r--r-- 4,813 bytes parent folder | download
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
/* $Id: platform.c,v 1.21 2014/01/21 01:59:29 tim Exp $ */

/*
 * Copyright (c) 2006 Darren Tucker.  All rights reserved.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include "includes.h"

#include <sys/types.h>

#include <stdarg.h>
#include <unistd.h>

#include "log.h"
#include "buffer.h"
#include "servconf.h"
#include "key.h"
#include "hostfile.h"
#include "auth.h"
#include "auth-pam.h"
#include "platform.h"

#include "openbsd-compat/openbsd-compat.h"

extern int use_privsep;
extern ServerOptions options;

void
platform_pre_listen(void)
{
#ifdef LINUX_OOM_ADJUST
	/* Adjust out-of-memory killer so listening process is not killed */
	oom_adjust_setup();
#endif
}

void
platform_pre_fork(void)
{
#ifdef USE_SOLARIS_PROCESS_CONTRACTS
	solaris_contract_pre_fork();
#endif
}

void
platform_pre_restart(void)
{
#ifdef LINUX_OOM_ADJUST
	oom_adjust_restore();
#endif
}

void
platform_post_fork_parent(pid_t child_pid)
{
#ifdef USE_SOLARIS_PROCESS_CONTRACTS
	solaris_contract_post_fork_parent(child_pid);
#endif
}

void
platform_post_fork_child(void)
{
#ifdef USE_SOLARIS_PROCESS_CONTRACTS
	solaris_contract_post_fork_child();
#endif
#ifdef LINUX_OOM_ADJUST
	oom_adjust_restore();
#endif
}

/* return 1 if we are running with privilege to swap UIDs, 0 otherwise */
int
platform_privileged_uidswap(void)
{
#ifdef HAVE_CYGWIN
	/* uid 0 is not special on Cygwin so always try */
	return 1;
#else
	return (getuid() == 0 || geteuid() == 0);
#endif
}

/*
 * This gets called before switching UIDs, and is called even when sshd is
 * not running as root.
 */
void
platform_setusercontext(struct passwd *pw)
{
#ifdef WITH_SELINUX
	/* Cache selinux status for later use */
	(void)ssh_selinux_enabled();
#endif

#ifdef USE_SOLARIS_PROJECTS
	/* if solaris projects were detected, set the default now */
	if (getuid() == 0 || geteuid() == 0)
		solaris_set_default_project(pw);
#endif

#if defined(HAVE_LOGIN_CAP) && defined (__bsdi__)
	if (getuid() == 0 || geteuid() == 0)
		setpgid(0, 0);
# endif

#if defined(HAVE_LOGIN_CAP) && defined(USE_PAM)
	/*
	 * If we have both LOGIN_CAP and PAM, we want to establish creds
	 * before calling setusercontext (in session.c:do_setusercontext).
	 */
	if (getuid() == 0 || geteuid() == 0) {
		if (options.use_pam) {
			do_pam_setcred(use_privsep);
		}
	}
# endif /* USE_PAM */

#if !defined(HAVE_LOGIN_CAP) && defined(HAVE_GETLUID) && defined(HAVE_SETLUID)
	if (getuid() == 0 || geteuid() == 0) {
		/* Sets login uid for accounting */
		if (getluid() == -1 && setluid(pw->pw_uid) == -1)
			error("setluid: %s", strerror(errno));
	}
#endif
}

/*
 * This gets called after we've established the user's groups, and is only
 * called if sshd is running as root.
 */
void
platform_setusercontext_post_groups(struct passwd *pw, const char *role)
{
#if !defined(HAVE_LOGIN_CAP) && defined(USE_PAM)
	/*
	 * PAM credentials may take the form of supplementary groups.
	 * These will have been wiped by the above initgroups() call.
	 * Reestablish them here.
	 */
	if (options.use_pam) {
		do_pam_setcred(use_privsep);
	}
#endif /* USE_PAM */

#if !defined(HAVE_LOGIN_CAP) && (defined(WITH_IRIX_PROJECT) || \
    defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY))
	irix_setusercontext(pw);
#endif /* defined(WITH_IRIX_PROJECT) || defined(WITH_IRIX_JOBS) || defined(WITH_IRIX_ARRAY) */

#ifdef _AIX
	aix_usrinfo(pw);
#endif /* _AIX */

#ifdef HAVE_SETPCRED
	/*
	 * If we have a chroot directory, we set all creds except real
	 * uid which we will need for chroot.  If we don't have a
	 * chroot directory, we don't override anything.
	 */
	{
		char **creds = NULL, *chroot_creds[] =
		    { "REAL_USER=root", NULL };

		if (options.chroot_directory != NULL &&
		    strcasecmp(options.chroot_directory, "none") != 0)
			creds = chroot_creds;

		if (setpcred(pw->pw_name, creds) == -1)
			fatal("Failed to set process credentials");
	}
#endif /* HAVE_SETPCRED */
#ifdef WITH_SELINUX
	ssh_selinux_setup_exec_context(pw->pw_name, role);
#endif
}

char *
platform_krb5_get_principal_name(const char *pw_name)
{
#ifdef USE_AIX_KRB_NAME
	return aix_krb5_get_principal_name(pw_name);
#else
	return NULL;
#endif
}