Copyright 2012 Dan Walsh
systemd is free software; you can redistribute it and/or modify it
- under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- General Public License for more details.
+ Lesser General Public License for more details.
- You should have received a copy of the GNU General Public License
+ You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <limits.h>
#include <selinux/selinux.h>
#include <selinux/avc.h>
+#include <sys/socket.h>
#ifdef HAVE_AUDIT
#include <libaudit.h>
#endif
-#include <dbus.h>
+#include "sd-bus.h"
+#include "bus-util.h"
#include "util.h"
#include "log.h"
-#include "bus-errors.h"
-#include "dbus-common.h"
#include "audit.h"
#include "selinux-util.h"
#include "audit-fd.h"
+#include "strv.h"
static bool initialized = false;
-struct auditstruct {
+struct audit_info {
+ sd_bus_creds *creds;
const char *path;
- char *cmdline;
- uid_t loginuid;
- uid_t uid;
- gid_t gid;
+ const char *cmdline;
};
-static int bus_get_selinux_security_context(
- DBusConnection *connection,
- const char *name,
- char **scon,
- DBusError *error) {
-
- _cleanup_dbus_message_unref_ DBusMessage *m = NULL, *reply = NULL;
- DBusMessageIter iter, sub;
- const char *bytes;
- char *b;
- int nbytes;
-
- m = dbus_message_new_method_call(
- DBUS_SERVICE_DBUS,
- DBUS_PATH_DBUS,
- DBUS_INTERFACE_DBUS,
- "GetConnectionSELinuxSecurityContext");
- if (!m) {
- dbus_set_error_const(error, DBUS_ERROR_NO_MEMORY, NULL);
- return -ENOMEM;
- }
-
- if (!dbus_message_append_args(
- m,
- DBUS_TYPE_STRING, &name,
- DBUS_TYPE_INVALID)) {
- dbus_set_error_const(error, DBUS_ERROR_NO_MEMORY, NULL);
- return -ENOMEM;
- }
-
- reply = dbus_connection_send_with_reply_and_block(connection, m, -1, error);
- if (!reply)
- return -EIO;
-
- if (dbus_set_error_from_message(error, reply))
- return -EIO;
-
- if (!dbus_message_iter_init(reply, &iter))
- return -EIO;
-
- if (dbus_message_iter_get_arg_type(&iter) != DBUS_TYPE_ARRAY)
- return -EIO;
-
- dbus_message_iter_recurse(&iter, &sub);
- dbus_message_iter_get_fixed_array(&sub, &bytes, &nbytes);
-
- b = strndup(bytes, nbytes);
- if (!b)
- return -ENOMEM;
-
- *scon = b;
-
- return 0;
-}
-
-static int bus_get_audit_data(
- DBusConnection *connection,
- const char *name,
- struct auditstruct *audit,
- DBusError *error) {
-
- pid_t pid;
- int r;
-
- pid = bus_get_unix_process_id(connection, name, error);
- if (pid <= 0)
- return -EIO;
-
- r = audit_loginuid_from_pid(pid, &audit->loginuid);
- if (r < 0)
- return r;
-
- r = get_process_uid(pid, &audit->uid);
- if (r < 0)
- return r;
-
- r = get_process_gid(pid, &audit->gid);
- if (r < 0)
- return r;
-
- r = get_process_cmdline(pid, 0, true, &audit->cmdline);
- if (r < 0)
- return r;
-
- return 0;
-}
-
/*
Any time an access gets denied this callback will be called
- with the aduit data. We then need to just copy the audit data into the msgbuf.
+ with the audit data. We then need to just copy the audit data into the msgbuf.
*/
static int audit_callback(
void *auditdata,
char *msgbuf,
size_t msgbufsize) {
- struct auditstruct *audit = (struct auditstruct *) auditdata;
+ const struct audit_info *audit = auditdata;
+ uid_t uid = 0, login_uid = 0;
+ gid_t gid = 0;
+ char login_uid_buf[DECIMAL_STR_MAX(uid_t)] = "n/a";
+ char uid_buf[DECIMAL_STR_MAX(uid_t)] = "n/a";
+ char gid_buf[DECIMAL_STR_MAX(gid_t)] = "n/a";
+
+ if (sd_bus_creds_get_audit_login_uid(audit->creds, &login_uid) >= 0)
+ snprintf(login_uid_buf, sizeof(login_uid_buf), UID_FMT, login_uid);
+ if (sd_bus_creds_get_uid(audit->creds, &uid) >= 0)
+ snprintf(uid_buf, sizeof(uid_buf), UID_FMT, uid);
+ if (sd_bus_creds_get_gid(audit->creds, &gid) >= 0)
+ snprintf(gid_buf, sizeof(gid_buf), GID_FMT, gid);
snprintf(msgbuf, msgbufsize,
- "auid=%d uid=%d gid=%d%s%s%s%s%s%s",
- audit->loginuid,
- audit->uid,
- audit->gid,
- (audit->path ? " path=\"" : ""),
- strempty(audit->path),
- (audit->path ? "\"" : ""),
- (audit->cmdline ? " cmdline=\"" : ""),
- strempty(audit->cmdline),
- (audit->cmdline ? "\"" : ""));
+ "auid=%s uid=%s gid=%s%s%s%s%s%s%s",
+ login_uid_buf, uid_buf, gid_buf,
+ audit->path ? " path=\"" : "", strempty(audit->path), audit->path ? "\"" : "",
+ audit->cmdline ? " cmdline=\"" : "", strempty(audit->cmdline), audit->cmdline ? "\"" : "");
msgbuf[msgbufsize-1] = 0;
user_avc's into the /var/log/audit/audit.log, otherwise they will be
sent to syslog.
*/
-_printf_attr_(2, 3) static int log_callback(int type, const char *fmt, ...) {
+_printf_(2, 3) static int log_callback(int type, const char *fmt, ...) {
va_list ap;
- va_start(ap, fmt);
-
#ifdef HAVE_AUDIT
if (get_audit_fd() >= 0) {
_cleanup_free_ char *buf = NULL;
int r;
+ va_start(ap, fmt);
r = vasprintf(&buf, fmt, ap);
va_end(ap);
audit_log_user_avc_message(get_audit_fd(), AUDIT_USER_AVC, buf, NULL, NULL, NULL, 0);
return 0;
}
-
- va_start(ap, fmt);
}
#endif
+
+ va_start(ap, fmt);
log_metav(LOG_USER | LOG_INFO, __FILE__, __LINE__, __FUNCTION__, fmt, ap);
va_end(ap);
If you want to cleanup memory you should need to call selinux_access_finish.
*/
static int access_init(void) {
- int r;
+ int r = 0;
if (avc_open(NULL, 0)) {
log_error("avc_open() failed: %m");
selinux_set_callback(SELINUX_CB_AUDIT, (union selinux_callback) audit_callback);
selinux_set_callback(SELINUX_CB_LOG, (union selinux_callback) log_callback);
- if (security_getenforce() >= 0)
- return 0;
-
- r = -errno;
- avc_destroy();
+ if (security_getenforce() < 0){
+ r = -errno;
+ avc_destroy();
+ }
return r;
}
-static int selinux_access_init(DBusError *error) {
+static int mac_selinux_access_init(sd_bus_error *error) {
int r;
if (initialized)
return 0;
- if (use_selinux()) {
- r = access_init();
- if (r < 0) {
- dbus_set_error(error, DBUS_ERROR_ACCESS_DENIED, "Failed to initialize SELinux.");
- return r;
- }
- }
+ if (!mac_selinux_use())
+ return 0;
+
+ r = access_init();
+ if (r < 0)
+ return sd_bus_error_set(error, SD_BUS_ERROR_ACCESS_DENIED, "Failed to initialize SELinux.");
initialized = true;
return 0;
}
+#endif
-void selinux_access_free(void) {
+void mac_selinux_access_free(void) {
+
+#ifdef HAVE_SELINUX
if (!initialized)
return;
avc_destroy();
initialized = false;
-}
-
-static int get_audit_data(
- DBusConnection *connection,
- DBusMessage *message,
- struct auditstruct *audit,
- DBusError *error) {
-
- const char *sender;
- int r, fd;
- struct ucred ucred;
- socklen_t len = sizeof(ucred);
-
- sender = dbus_message_get_sender(message);
- if (sender)
- return bus_get_audit_data(connection, sender, audit, error);
-
- if (!dbus_connection_get_unix_fd(connection, &fd))
- return -EINVAL;
-
- r = getsockopt(fd, SOL_SOCKET, SO_PEERCRED, &ucred, &len);
- if (r < 0) {
- log_error("Failed to determine peer credentials: %m");
- return -errno;
- }
-
- audit->uid = ucred.uid;
- audit->gid = ucred.gid;
-
- r = audit_loginuid_from_pid(ucred.pid, &audit->loginuid);
- if (r < 0)
- return r;
-
- r = get_process_cmdline(ucred.pid, 0, true, &audit->cmdline);
- if (r < 0)
- return r;
-
- return 0;
-}
-
-/*
- This function returns the security context of the remote end of the dbus
- connections. Whether it is on the bus or a local connection.
-*/
-static int get_calling_context(
- DBusConnection *connection,
- DBusMessage *message,
- security_context_t *scon,
- DBusError *error) {
-
- const char *sender;
- int r;
- int fd;
-
- /*
- If sender exists then
- if sender is NULL this indicates a local connection. Grab the fd
- from dbus and do an getpeercon to peers process context
- */
- sender = dbus_message_get_sender(message);
- if (sender) {
- r = bus_get_selinux_security_context(connection, sender, scon, error);
- if (r >= 0)
- return r;
-
- log_error("bus_get_selinux_security_context failed: %m");
- return r;
- }
-
- if (!dbus_connection_get_unix_fd(connection, &fd)) {
- log_error("bus_connection_get_unix_fd failed %m");
- return -EINVAL;
- }
-
- r = getpeercon(fd, scon);
- if (r < 0) {
- log_error("getpeercon failed %m");
- return -errno;
- }
-
- return 0;
+#endif
}
/*
If the machine is in permissive mode it will return ok. Audit messages will
still be generated if the access would be denied in enforcing mode.
*/
-int selinux_access_check(
- DBusConnection *connection,
- DBusMessage *message,
+int mac_selinux_generic_access_check(
+ sd_bus_message *message,
const char *path,
const char *permission,
- DBusError *error) {
+ sd_bus_error *error) {
- security_context_t scon = NULL, fcon = NULL;
+#ifdef HAVE_SELINUX
+ _cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL;
+ const char *tclass = NULL, *scon = NULL;
+ struct audit_info audit_info = {};
+ _cleanup_free_ char *cl = NULL;
+ security_context_t fcon = NULL;
+ char **cmdline = NULL;
int r = 0;
- const char *tclass = NULL;
- struct auditstruct audit;
- assert(connection);
assert(message);
assert(permission);
assert(error);
- if (!use_selinux())
+ if (!mac_selinux_use())
return 0;
- r = selinux_access_init(error);
+ r = mac_selinux_access_init(error);
if (r < 0)
return r;
- audit.uid = audit.loginuid = (uid_t) -1;
- audit.gid = (gid_t) -1;
- audit.cmdline = NULL;
- audit.path = path;
+ r = sd_bus_query_sender_creds(
+ message,
+ SD_BUS_CREDS_PID|SD_BUS_CREDS_UID|SD_BUS_CREDS_GID|
+ SD_BUS_CREDS_CMDLINE|SD_BUS_CREDS_AUDIT_LOGIN_UID|
+ SD_BUS_CREDS_SELINUX_CONTEXT,
+ &creds);
+ if (r < 0)
+ goto finish;
- r = get_calling_context(connection, message, &scon, error);
- if (r < 0) {
- log_error("Failed to get caller's security context on: %m");
+ r = sd_bus_creds_get_selinux_context(creds, &scon);
+ if (r < 0)
goto finish;
- }
if (path) {
- tclass = "service";
- /* get the file context of the unit file */
+ /* Get the file context of the unit file */
+
r = getfilecon(path, &fcon);
if (r < 0) {
- dbus_set_error(error, DBUS_ERROR_ACCESS_DENIED, "Failed to get file context on %s.", path);
- r = -errno;
- log_error("Failed to get security context on %s: %m",path);
+ r = sd_bus_error_setf(error, SD_BUS_ERROR_ACCESS_DENIED, "Failed to get file context on %s.", path);
goto finish;
}
+ tclass = "service";
} else {
- tclass = "system";
r = getcon(&fcon);
if (r < 0) {
- dbus_set_error(error, DBUS_ERROR_ACCESS_DENIED, "Failed to get current context.");
- r = -errno;
- log_error("Failed to get current process context on: %m");
+ r = sd_bus_error_setf(error, SD_BUS_ERROR_ACCESS_DENIED, "Failed to get current context.");
goto finish;
}
+
+ tclass = "system";
}
- (void) get_audit_data(connection, message, &audit, error);
+ sd_bus_creds_get_cmdline(creds, &cmdline);
+ cl = strv_join(cmdline, " ");
- errno = 0;
- r = selinux_check_access(scon, fcon, tclass, permission, &audit);
- if (r < 0) {
- dbus_set_error(error, DBUS_ERROR_ACCESS_DENIED, "SELinux policy denies access.");
- r = -errno;
- log_error("SELinux policy denies access.");
- }
+ audit_info.creds = creds;
+ audit_info.path = path;
+ audit_info.cmdline = cl;
+
+ r = selinux_check_access((security_context_t) scon, fcon, tclass, permission, &audit_info);
+ if (r < 0)
+ r = sd_bus_error_setf(error, SD_BUS_ERROR_ACCESS_DENIED, "SELinux policy denies access.");
- log_debug("SELinux access check scon=%s tcon=%s tclass=%s perm=%s path=%s cmdline=%s: %i", scon, fcon, tclass, permission, path, audit.cmdline, r);
+ log_debug("SELinux access check scon=%s tcon=%s tclass=%s perm=%s path=%s cmdline=%s: %i", scon, fcon, tclass, permission, path, cl, r);
finish:
- free(audit.cmdline);
- freecon(scon);
freecon(fcon);
- if (r && security_getenforce() != 1) {
- dbus_error_init(error);
+ if (r < 0 && security_getenforce() != 1) {
+ sd_bus_error_free(error);
r = 0;
}
return r;
-}
-
#else
-
-int selinux_access_check(
- DBusConnection *connection,
- DBusMessage *message,
- const char *path,
- const char *permission,
- DBusError *error) {
-
return 0;
+#endif
}
-void selinux_access_free(void) {
-}
+int mac_selinux_unit_access_check_strv(char **units,
+ sd_bus_message *message,
+ Manager *m,
+ const char *permission,
+ sd_bus_error *error) {
+#ifdef HAVE_SELINUX
+ char **i;
+ Unit *u;
+ int r;
+ STRV_FOREACH(i, units) {
+ u = manager_get_unit(m, *i);
+ if (u) {
+ r = mac_selinux_unit_access_check(u, message, permission, error);
+ if (r < 0)
+ return r;
+ }
+ }
#endif
+ return 0;
+}
~ianmdlvl / elogind.git / blobdiff