4 * Copyright (c) 2005 Daniel Walsh <dwalsh@redhat.com>
5 * Copyright (c) 2006 Damien Miller <djm@openbsd.org>
7 * Permission to use, copy, modify, and distribute this software for any
8 * purpose with or without fee is hereby granted, provided that the above
9 * copyright notice and this permission notice appear in all copies.
11 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
21 * Linux-specific portability code - just SELinux support at present
31 #include "port-linux.h"
33 #include <selinux/selinux.h>
34 #include <selinux/flask.h>
35 #include <selinux/get_context_list.h>
37 /* Wrapper around is_selinux_enabled() to log its return value once only */
39 ssh_selinux_enabled(void)
41 static int enabled = -1;
44 enabled = is_selinux_enabled();
45 debug("SELinux support %s", enabled ? "enabled" : "disabled");
51 /* Return the default security context for the given username */
52 static security_context_t
53 ssh_selinux_getctxbyname(char *pwname)
55 security_context_t sc;
56 char *sename = NULL, *lvl = NULL;
59 #ifdef HAVE_GETSEUSERBYNAME
60 if (getseuserbyname(pwname, &sename, &lvl) != 0)
67 #ifdef HAVE_GET_DEFAULT_CONTEXT_WITH_LEVEL
68 r = get_default_context_with_level(sename, lvl, NULL, &sc);
70 r = get_default_context(sename, NULL, &sc);
74 switch (security_getenforce()) {
76 fatal("%s: ssh_selinux_getctxbyname: "
77 "security_getenforce() failed", __func__);
79 error("%s: Failed to get default SELinux security "
80 "context for %s", __func__, pwname);
82 fatal("%s: Failed to get default SELinux security "
83 "context for %s (in enforcing mode)",
88 #ifdef HAVE_GETSEUSERBYNAME
98 /* Set the execution context to the default for the specified user */
100 ssh_selinux_setup_exec_context(char *pwname)
102 security_context_t user_ctx = NULL;
104 if (!ssh_selinux_enabled())
107 debug3("%s: setting execution context", __func__);
109 user_ctx = ssh_selinux_getctxbyname(pwname);
110 if (setexeccon(user_ctx) != 0) {
111 switch (security_getenforce()) {
113 fatal("%s: security_getenforce() failed", __func__);
115 error("%s: Failed to set SELinux execution "
116 "context for %s", __func__, pwname);
118 fatal("%s: Failed to set SELinux execution context "
119 "for %s (in enforcing mode)", __func__, pwname);
122 if (user_ctx != NULL)
125 debug3("%s: done", __func__);
128 /* Set the TTY context for the specified user */
130 ssh_selinux_setup_pty(char *pwname, const char *tty)
132 security_context_t new_tty_ctx = NULL;
133 security_context_t user_ctx = NULL;
134 security_context_t old_tty_ctx = NULL;
136 if (!ssh_selinux_enabled())
139 debug3("%s: setting TTY context on %s", __func__, tty);
141 user_ctx = ssh_selinux_getctxbyname(pwname);
143 /* XXX: should these calls fatal() upon failure in enforcing mode? */
145 if (getfilecon(tty, &old_tty_ctx) == -1) {
146 error("%s: getfilecon: %s", __func__, strerror(errno));
150 if (security_compute_relabel(user_ctx, old_tty_ctx,
151 SECCLASS_CHR_FILE, &new_tty_ctx) != 0) {
152 error("%s: security_compute_relabel: %s",
153 __func__, strerror(errno));
157 if (setfilecon(tty, new_tty_ctx) != 0)
158 error("%s: setfilecon: %s", __func__, strerror(errno));
160 if (new_tty_ctx != NULL)
161 freecon(new_tty_ctx);
162 if (old_tty_ctx != NULL)
163 freecon(old_tty_ctx);
164 if (user_ctx != NULL)
166 debug3("%s: done", __func__);
168 #endif /* WITH_SELINUX */