/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*-
* selinux.c SELinux security checks for D-Bus
*
* Author: Matthew Rickard <mjricka@epoch.ncsc.mil>
*
* Licensed under the Academic Free License version 2.1
*
* This program 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
* (at your option) any later version.
*
* This program 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*
*/
#include <config.h>
#include <dbus/dbus-internals.h>
#include <dbus/dbus-string.h>
#ifndef DBUS_WIN
#include <dbus/dbus-userdb.h>
#endif
#include "selinux.h"
#include "services.h"
#include "policy.h"
#include "utils.h"
#include "config-parser.h"
#ifdef HAVE_ERRNO_H
#include <errno.h>
#endif
#ifdef HAVE_SELINUX
#include <sys/types.h>
#include <unistd.h>
#include <limits.h>
#include <pthread.h>
#include <syslog.h>
#include <selinux/selinux.h>
#include <selinux/avc.h>
#include <selinux/av_permissions.h>
#include <selinux/flask.h>
#include <signal.h>
#include <stdarg.h>
#include <stdio.h>
#include <grp.h>
#endif /* HAVE_SELINUX */
#ifdef HAVE_LIBAUDIT
#include <cap-ng.h>
#include <libaudit.h>
#endif /* HAVE_LIBAUDIT */
#define BUS_SID_FROM_SELINUX(sid) ((BusSELinuxID*) (sid))
#define SELINUX_SID_FROM_BUS(sid) ((security_id_t) (sid))
#ifdef HAVE_SELINUX
/* Store the value telling us if SELinux is enabled in the kernel. */
static dbus_bool_t selinux_enabled = FALSE;
/* Store an avc_entry_ref to speed AVC decisions. */
static struct avc_entry_ref aeref;
/* Store the SID of the bus itself to use as the default. */
static security_id_t bus_sid = SECSID_WILD;
/* Thread to listen for SELinux status changes via netlink. */
static pthread_t avc_notify_thread;
/* Prototypes for AVC callback functions. */
static void log_callback (const char *fmt, ...);
static void log_audit_callback (void *data, security_class_t class, char *buf, size_t bufleft);
static void *avc_create_thread (void (*run) (void));
static void avc_stop_thread (void *thread);
static void *avc_alloc_lock (void);
static void avc_get_lock (void *lock);
static void avc_release_lock (void *lock);
static void avc_free_lock (void *lock);
/* AVC callback structures for use in avc_init. */
static const struct avc_memory_callback mem_cb =
{
.func_malloc = dbus_malloc,
.func_free = dbus_free
};
static const struct avc_log_callback log_cb =
{
.func_log = log_callback,
.func_audit = log_audit_callback
};
static const struct avc_thread_callback thread_cb =
{
.func_create_thread = avc_create_thread,
.func_stop_thread = avc_stop_thread
};
static const struct avc_lock_callback lock_cb =
{
.func_alloc_lock = avc_alloc_lock,
.func_get_lock = avc_get_lock,
.func_release_lock = avc_release_lock,
.func_free_lock = avc_free_lock
};
#endif /* HAVE_SELINUX */
/**
* Log callback to log denial messages from the AVC.
* This is used in avc_init. Logs to both standard
* error and syslogd.
*
* @param fmt the format string
* @param variable argument list
*/
#ifdef HAVE_SELINUX
#ifdef HAVE_LIBAUDIT
static int audit_fd = -1;
#endif
void
bus_selinux_audit_init(void)
{
#ifdef HAVE_LIBAUDIT
audit_fd = audit_open ();
if (audit_fd < 0)
{
/* If kernel doesn't support audit, bail out */
if (errno == EINVAL || errno == EPROTONOSUPPORT || errno == EAFNOSUPPORT)
return;
/* If user bus, bail out */
if (errno == EPERM && getuid() != 0)
return;
_dbus_warn ("Failed opening connection to the audit subsystem");
}
#endif /* HAVE_LIBAUDIT */
}
static void
log_callback (const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
#ifdef HAVE_LIBAUDIT
if (audit_fd >= 0)
{
capng_get_caps_process();
if (capng_have_capability(CAPNG_EFFECTIVE, CAP_AUDIT_WRITE))
{
char buf[PATH_MAX*2];
/* FIXME: need to change this to show real user */
vsnprintf(buf, sizeof(buf), fmt, ap);
audit_log_user_avc_message(audit_fd, AUDIT_USER_AVC, buf, NULL, NULL,
NULL, getuid());
return;
}
}
#endif /* HAVE_LIBAUDIT */
vsyslog (LOG_USER | LOG_INFO, fmt, ap);
va_end(ap);
}
/**
* On a policy reload we need to reparse the SELinux configuration file, since
* this could have changed. Send a SIGHUP to reload all configs.
*/
static int
policy_reload_callback (u_int32_t event, security_id_t ssid,
security_id_t tsid, security_class_t tclass,
access_vector_t perms, access_vector_t *out_retained)
{
if (event == AVC_CALLBACK_RESET)
return raise (SIGHUP);
return 0;
}
/**
* Log any auxiliary data
*/
static void
log_audit_callback (void *data, security_class_t class, char *buf, size_t bufleft)
{
DBusString *audmsg = data;
if (bufleft > (size_t) _dbus_string_get_length(audmsg))
{
_dbus_string_copy_to_buffer_with_nul (audmsg, buf, bufleft);
}
else
{
DBusString s;
_dbus_string_init_const(&s, "Buffer too small for audit message");
if (bufleft > (size_t) _dbus_string_get_length(&s))
_dbus_string_copy_to_buffer_with_nul (&s, buf, bufleft);
}
}
/**
* Create thread to notify the AVC of enforcing and policy reload
* changes via netlink.
*
* @param run the thread run function
* @return pointer to the thread
*/
static void *
avc_create_thread (void (*run) (void))
{
int rc;
rc = pthread_create (&avc_notify_thread, NULL, (void *(*) (void *)) run, NULL);
if (rc != 0)
{
_dbus_warn ("Failed to start AVC thread: %s\n", _dbus_strerror (rc));
exit (1);
}
return &avc_notify_thread;
}
/* Stop AVC netlink thread. */
static void
avc_stop_thread (void *thread)
{
pthread_cancel (*(pthread_t *) thread);
}
/* Allocate a new AVC lock. */
static void *
avc_alloc_lock (void)
{
pthread_mutex_t *avc_mutex;
avc_mutex = dbus_new (pthread_mutex_t, 1);
if (avc_mutex == NULL)
{
_dbus_warn ("Could not create mutex: %s\n", _dbus_strerror (errno));
exit (1);
}
pthread_mutex_init (avc_mutex, NULL);
return avc_mutex;
}
/* Acquire an AVC lock. */
static void
avc_get_lock (void *lock)
{
pthread_mutex_lock (lock);
}
/* Release an AVC lock. */
static void
avc_release_lock (void *lock)
{
pthread_mutex_unlock (lock);
}
/* Free an AVC lock. */
static void
avc_free_lock (void *lock)
{
pthread_mutex_destroy (lock);
dbus_free (lock);
}
#endif /* HAVE_SELINUX */
/**
* Return whether or not SELinux is enabled; must be
* called after bus_selinux_init.
*/
dbus_bool_t
bus_selinux_enabled (void)
{
#ifdef HAVE_SELINUX
return selinux_enabled;
#else
return FALSE;
#endif /* HAVE_SELINUX */
}
/**
* Do early initialization; determine whether SELinux is enabled.
*/
dbus_bool_t
bus_selinux_pre_init (void)
{
#ifdef HAVE_SELINUX
int r;
_dbus_assert (bus_sid == SECSID_WILD);
/* Determine if we are running an SELinux kernel. */
r = is_selinux_enabled ();
if (r < 0)
{
_dbus_warn ("Could not tell if SELinux is enabled: %s\n",
_dbus_strerror (errno));
return FALSE;
}
selinux_enabled = r != 0;
return TRUE;
#else
return TRUE;
#endif
}
/**
* Initialize the user space access vector cache (AVC) for D-Bus and set up
* logging callbacks.
*/
dbus_bool_t
bus_selinux_full_init (void)
{
#ifdef HAVE_SELINUX
char *bus_context;
_dbus_assert (bus_sid == SECSID_WILD);
if (!selinux_enabled)
{
_dbus_verbose ("SELinux not enabled in this kernel.\n");
return TRUE;
}
_dbus_verbose ("SELinux is enabled in this kernel.\n");
avc_entry_ref_init (&aeref);
if (avc_init ("avc", &mem_cb, &log_cb, &thread_cb, &lock_cb) < 0)
{
_dbus_warn ("Failed to start Access Vector Cache (AVC).\n");
return FALSE;
}
else
{
_dbus_verbose ("Access Vector Cache (AVC) started.\n");
}
if (avc_add_callback (policy_reload_callback, AVC_CALLBACK_RESET,
NULL, NULL, 0, 0) < 0)
{
_dbus_warn ("Failed to add policy reload callback: %s\n",
_dbus_strerror (errno));
avc_destroy ();
return FALSE;
}
bus_context = NULL;
bus_sid = SECSID_WILD;
if (getcon (&bus_context) < 0)
{
_dbus_verbose ("Error getting context of bus: %s\n",
_dbus_strerror (errno));
return FALSE;
}
if (avc_context_to_sid (bus_context, &bus_sid) < 0)
{
_dbus_verbose ("Error getting SID from bus context: %s\n",
_dbus_strerror (errno));
freecon (bus_context);
return FALSE;
}
freecon (bus_context);
#endif /* HAVE_SELINUX */
return TRUE;
}
/**
* Decrement SID reference count.
*
* @param sid the SID to decrement
*/
void
bus_selinux_id_unref (BusSELinuxID *sid)
{
#ifdef HAVE_SELINUX
if (!selinux_enabled)
return;
_dbus_assert (sid != NULL);
sidput (SELINUX_SID_FROM_BUS (sid));
#endif /* HAVE_SELINUX */
}
void
bus_selinux_id_ref (BusSELinuxID *sid)
{
#ifdef HAVE_SELINUX
if (!selinux_enabled)
return;
_dbus_assert (sid != NULL);
sidget (SELINUX_SID_FROM_BUS (sid));
#endif /* HAVE_SELINUX */
}
/**
* Determine if the SELinux security policy allows the given sender
* security context to go to the given recipient security context.
* This function determines if the requested permissions are to be
* granted from the connection to the message bus or to another
* optionally supplied security identifier (e.g. for a service
* context). Currently these permissions are either send_msg or
* acquire_svc in the dbus class.
*
* @param sender_sid source security context
* @param override_sid is the target security context. If SECSID_WILD this will
* use the context of the bus itself (e.g. the default).
* @param target_class is the target security class.
* @param requested is the requested permissions.
* @returns #TRUE if security policy allows the send.
*/
#ifdef HAVE_SELINUX
static dbus_bool_t
bus_selinux_check (BusSELinuxID *sender_sid,
BusSELinuxID *override_sid,
security_class_t target_class,
access_vector_t requested,
DBusString *auxdata)
{
if (!selinux_enabled)
return TRUE;
/* Make the security check. AVC checks enforcing mode here as well. */
if (avc_has_perm (SELINUX_SID_FROM_BUS (sender_sid),
override_sid ?
SELINUX_SID_FROM_BUS (override_sid) :
SELINUX_SID_FROM_BUS (bus_sid),
target_class, requested, &aeref, auxdata) < 0)
{
switch (errno)
{
case EACCES:
_dbus_verbose ("SELinux denying due to security policy.\n");
return FALSE;
case EINVAL:
_dbus_verbose ("SELinux denying due to invalid security context.\n");
return FALSE;
default:
_dbus_verbose ("SELinux denying due to: %s\n", _dbus_strerror (errno));
return FALSE;
}
}
else
return TRUE;
}
#endif /* HAVE_SELINUX */
/**
* Returns true if the given connection can acquire a service,
* assuming the given security ID is needed for that service.
*
* @param connection connection that wants to own the service
* @param service_sid the SID of the service from the table
* @returns #TRUE if acquire is permitted.
*/
dbus_bool_t
bus_selinux_allows_acquire_service (DBusConnection *connection,
BusSELinuxID *service_sid,
const char *service_name,
DBusError *error)
{
#ifdef HAVE_SELINUX
BusSELinuxID *connection_sid;
unsigned long spid;
DBusString auxdata;
dbus_bool_t ret;
if (!selinux_enabled)
return TRUE;
connection_sid = bus_connection_get_selinux_id (connection);
if (!dbus_connection_get_unix_process_id (connection, &spid))
spid = 0;
if (!_dbus_string_init (&auxdata))
goto oom;
if (!_dbus_string_append (&auxdata, "service="))
goto oom;
if (!_dbus_string_append (&auxdata, service_name))
goto oom;
if (spid)
{
if (!_dbus_string_append (&auxdata, " spid="))
goto oom;
if (!_dbus_string_append_uint (&auxdata, spid))
goto oom;
}
ret = bus_selinux_check (connection_sid,
service_sid,
SECCLASS_DBUS,
DBUS__ACQUIRE_SVC,
&auxdata);
_dbus_string_free (&auxdata);
return ret;
oom:
_dbus_string_free (&auxdata);
BUS_SET_OOM (error);
return FALSE;
#else
return TRUE;
#endif /* HAVE_SELINUX */
}
/**
* Check if SELinux security controls allow the message to be sent to a
* particular connection based on the security context of the sender and
* that of the receiver. The destination connection need not be the
* addressed recipient, it could be an "eavesdropper"
*
* @param sender the sender of the message.
* @param proposed_recipient the connection the message is to be sent to.
* @returns whether to allow the send
*/
dbus_bool_t
bus_selinux_allows_send (DBusConnection *sender,
DBusConnection *proposed_recipient,
const char *msgtype,
const char *interface,
const char *member,
const char *error_name,
const char *destination,
DBusError *error)
{
#ifdef HAVE_SELINUX
BusSELinuxID *recipient_sid;
BusSELinuxID *sender_sid;
unsigned long spid, tpid;
DBusString auxdata;
dbus_bool_t ret;
dbus_bool_t string_alloced;
if (!selinux_enabled)
return TRUE;
if (!sender || !dbus_connection_get_unix_process_id (sender, &spid))
spid = 0;
if (!proposed_recipient || !dbus_connection_get_unix_process_id (proposed_recipient, &tpid))
tpid = 0;
string_alloced = FALSE;
if (!_dbus_string_init (&auxdata))
goto oom;
string_alloced = TRUE;
if (!_dbus_string_append (&auxdata, "msgtype="))
goto oom;
if (!_dbus_string_append (&auxdata, msgtype))
goto oom;
if (interface)
{
if (!_dbus_string_append (&auxdata, " interface="))
goto oom;
if (!_dbus_string_append (&auxdata, interface))
goto oom;
}
if (member)
{
if (!_dbus_string_append (&auxdata, " member="))
goto oom;
if (!_dbus_string_append (&auxdata, member))
goto oom;
}
if (error_name)
{
if (!_dbus_string_append (&auxdata, " error_name="))
goto oom;
if (!_dbus_string_append (&auxdata, error_name))
goto oom;
}
if (destination)
{
if (!_dbus_string_append (&auxdata, " dest="))
goto oom;
if (!_dbus_string_append (&auxdata, destination))
goto oom;
}
if (spid)
{
if (!_dbus_string_append (&auxdata, " spid="))
goto oom;
if (!_dbus_string_append_uint (&auxdata, spid))
goto oom;
}
if (tpid)
{
if (!_dbus_string_append (&auxdata, " tpid="))
goto oom;
if (!_dbus_string_append_uint (&auxdata, tpid))
goto oom;
}
sender_sid = bus_connection_get_selinux_id (sender);
/* A NULL proposed_recipient means the bus itself. */
if (proposed_recipient)
recipient_sid = bus_connection_get_selinux_id (proposed_recipient);
else
recipient_sid = BUS_SID_FROM_SELINUX (bus_sid);
ret = bus_selinux_check (sender_sid,
recipient_sid,
SECCLASS_DBUS,
DBUS__SEND_MSG,
&auxdata);
_dbus_string_free (&auxdata);
return ret;
oom:
if (string_alloced)
_dbus_string_free (&auxdata);
BUS_SET_OOM (error);
return FALSE;
#else
return TRUE;
#endif /* HAVE_SELINUX */
}
dbus_bool_t
bus_selinux_append_context (DBusMessage *message,
BusSELinuxID *sid,
DBusError *error)
{
#ifdef HAVE_SELINUX
char *context;
if (avc_sid_to_context (SELINUX_SID_FROM_BUS (sid), &context) < 0)
{
if (errno == ENOMEM)
BUS_SET_OOM (error);
else
dbus_set_error (error, DBUS_ERROR_FAILED,
"Error getting context from SID: %s\n",
_dbus_strerror (errno));
return FALSE;
}
if (!dbus_message_append_args (message,
DBUS_TYPE_ARRAY,
DBUS_TYPE_BYTE,
&context,
strlen (context),
DBUS_TYPE_INVALID))
{
_DBUS_SET_OOM (error);
return FALSE;
}
freecon (context);
return TRUE;
#else
return TRUE;
#endif
}
/**
* Gets the security context of a connection to the bus. It is up to
* the caller to freecon() when they are done.
*
* @param connection the connection to get the context of.
* @param con the location to store the security context.
* @returns #TRUE if context is successfully obtained.
*/
#ifdef HAVE_SELINUX
static dbus_bool_t
bus_connection_read_selinux_context (DBusConnection *connection,
char **con)
{
int fd;
if (!selinux_enabled)
return FALSE;
_dbus_assert (connection != NULL);
if (!dbus_connection_get_unix_fd (connection, &fd))
{
_dbus_verbose ("Failed to get file descriptor of socket.\n");
return FALSE;
}
if (getpeercon (fd, con) < 0)
{
_dbus_verbose ("Error getting context of socket peer: %s\n",
_dbus_strerror (errno));
return FALSE;
}
_dbus_verbose ("Successfully read connection context.\n");
return TRUE;
}
#endif /* HAVE_SELINUX */
/**
* Read the SELinux ID from the connection.
*
* @param connection the connection to read from
* @returns the SID if successfully determined, #NULL otherwise.
*/
BusSELinuxID*
bus_selinux_init_connection_id (DBusConnection *connection,
DBusError *error)
{
#ifdef HAVE_SELINUX
char *con;
security_id_t sid;
if (!selinux_enabled)
return NULL;
if (!bus_connection_read_selinux_context (connection, &con))
{
dbus_set_error (error, DBUS_ERROR_FAILED,
"Failed to read an SELinux context from connection");
_dbus_verbose ("Error getting peer context.\n");
return NULL;
}
_dbus_verbose ("Converting context to SID to store on connection\n");
if (avc_context_to_sid (con, &sid) < 0)
{
if (errno == ENOMEM)
BUS_SET_OOM (error);
else
dbus_set_error (error, DBUS_ERROR_FAILED,
"Error getting SID from context \"%s\": %s\n",
con, _dbus_strerror (errno));
_dbus_warn ("Error getting SID from context \"%s\": %s\n",
con, _dbus_strerror (errno));
freecon (con);
return NULL;
}
freecon (con);
return BUS_SID_FROM_SELINUX (sid);
#else
return NULL;
#endif /* HAVE_SELINUX */
}
/**
* Function for freeing hash table data. These SIDs
* should no longer be referenced.
*/
static void
bus_selinux_id_table_free_value (BusSELinuxID *sid)
{
#ifdef HAVE_SELINUX
/* NULL sometimes due to how DBusHashTable works */
if (sid)
bus_selinux_id_unref (sid);
#endif /* HAVE_SELINUX */
}
/**
* Creates a new table mapping service names to security ID.
* A security ID is a "compiled" security context, a security
* context is just a string.
*
* @returns the new table or #NULL if no memory
*/
DBusHashTable*
bus_selinux_id_table_new (void)
{
return _dbus_hash_table_new (DBUS_HASH_STRING,
(DBusFreeFunction) dbus_free,
(DBusFreeFunction) bus_selinux_id_table_free_value);
}
/**
* Hashes a service name and service context into the service SID
* table as a string and a SID.
*
* @param service_name is the name of the service.
* @param service_context is the context of the service.
* @param service_table is the table to hash them into.
* @return #FALSE if not enough memory
*/
dbus_bool_t
bus_selinux_id_table_insert (DBusHashTable *service_table,
const char *service_name,
const char *service_context)
{
#ifdef HAVE_SELINUX
dbus_bool_t retval;
security_id_t sid;
char *key;
if (!selinux_enabled)
return TRUE;
sid = SECSID_WILD;
retval = FALSE;
key = _dbus_strdup (service_name);
if (key == NULL)
return retval;
if (avc_context_to_sid ((char *) service_context, &sid) < 0)
{
if (errno == ENOMEM)
{
dbus_free (key);
return FALSE;
}
_dbus_warn ("Error getting SID from context \"%s\": %s\n",
(char *) service_context,
_dbus_strerror (errno));
goto out;
}
if (!_dbus_hash_table_insert_string (service_table,
key,
BUS_SID_FROM_SELINUX (sid)))
goto out;
_dbus_verbose ("Parsed \tservice: %s \n\t\tcontext: %s\n",
key,
sid->ctx);
/* These are owned by the hash, so clear them to avoid unref */
key = NULL;
sid = SECSID_WILD;
retval = TRUE;
out:
if (sid != SECSID_WILD)
sidput (sid);
if (key)
dbus_free (key);
return retval;
#else
return TRUE;
#endif /* HAVE_SELINUX */
}
/**
* Find the security identifier associated with a particular service
* name. Return a pointer to this SID, or #NULL/SECSID_WILD if the
* service is not found in the hash table. This should be nearly a
* constant time operation. If SELinux support is not available,
* always return NULL.
*
* @param service_table the hash table to check for service name.
* @param service_name the name of the service to look for.
* @returns the SELinux ID associated with the service
*/
BusSELinuxID*
bus_selinux_id_table_lookup (DBusHashTable *service_table,
const DBusString *service_name)
{
#ifdef HAVE_SELINUX
security_id_t sid;
sid = SECSID_WILD; /* default context */
if (!selinux_enabled)
return NULL;
_dbus_verbose ("Looking up service SID for %s\n",
_dbus_string_get_const_data (service_name));
sid = _dbus_hash_table_lookup_string (service_table,
_dbus_string_get_const_data (service_name));
if (sid == SECSID_WILD)
_dbus_verbose ("Service %s not found\n",
_dbus_string_get_const_data (service_name));
else
_dbus_verbose ("Service %s found\n",
_dbus_string_get_const_data (service_name));
return BUS_SID_FROM_SELINUX (sid);
#endif /* HAVE_SELINUX */
return NULL;
}
/**
* Get the SELinux policy root. This is used to find the D-Bus
* specific config file within the policy.
*/
const char *
bus_selinux_get_policy_root (void)
{
#ifdef HAVE_SELINUX
return selinux_policy_root ();
#else
return NULL;
#endif /* HAVE_SELINUX */
}
/**
* For debugging: Print out the current hash table of service SIDs.
*/
void
bus_selinux_id_table_print (DBusHashTable *service_table)
{
#ifdef DBUS_ENABLE_VERBOSE_MODE
#ifdef HAVE_SELINUX
DBusHashIter iter;
if (!selinux_enabled)
return;
_dbus_verbose ("Service SID Table:\n");
_dbus_hash_iter_init (service_table, &iter);
while (_dbus_hash_iter_next (&iter))
{
const char *key = _dbus_hash_iter_get_string_key (&iter);
security_id_t sid = _dbus_hash_iter_get_value (&iter);
_dbus_verbose ("The key is %s\n", key);
_dbus_verbose ("The context is %s\n", sid->ctx);
_dbus_verbose ("The refcount is %d\n", sid->refcnt);
}
#endif /* HAVE_SELINUX */
#endif /* DBUS_ENABLE_VERBOSE_MODE */
}
#ifdef DBUS_ENABLE_VERBOSE_MODE
#ifdef HAVE_SELINUX
/**
* Print out some AVC statistics.
*/
static void
bus_avc_print_stats (void)
{
struct avc_cache_stats cstats;
if (!selinux_enabled)
return;
_dbus_verbose ("AVC Statistics:\n");
avc_cache_stats (&cstats);
avc_av_stats ();
_dbus_verbose ("AVC Cache Statistics:\n");
_dbus_verbose ("Entry lookups: %d\n", cstats.entry_lookups);
_dbus_verbose ("Entry hits: %d\n", cstats.entry_hits);
_dbus_verbose ("Entry misses %d\n", cstats.entry_misses);
_dbus_verbose ("Entry discards: %d\n", cstats.entry_discards);
_dbus_verbose ("CAV lookups: %d\n", cstats.cav_lookups);
_dbus_verbose ("CAV hits: %d\n", cstats.cav_hits);
_dbus_verbose ("CAV probes: %d\n", cstats.cav_probes);
_dbus_verbose ("CAV misses: %d\n", cstats.cav_misses);
}
#endif /* HAVE_SELINUX */
#endif /* DBUS_ENABLE_VERBOSE_MODE */
/**
* Destroy the AVC before we terminate.
*/
void
bus_selinux_shutdown (void)
{
#ifdef HAVE_SELINUX
if (!selinux_enabled)
return;
_dbus_verbose ("AVC shutdown\n");
if (bus_sid != SECSID_WILD)
{
sidput (bus_sid);
bus_sid = SECSID_WILD;
#ifdef DBUS_ENABLE_VERBOSE_MODE
if (_dbus_is_verbose())
bus_avc_print_stats ();
#endif /* DBUS_ENABLE_VERBOSE_MODE */
avc_destroy ();
#ifdef HAVE_LIBAUDIT
audit_close (audit_fd);
#endif /* HAVE_LIBAUDIT */
}
#endif /* HAVE_SELINUX */
}
/* The !HAVE_LIBAUDIT case lives in dbus-sysdeps-util-unix.c */
#ifdef HAVE_LIBAUDIT
/**
* Changes the user and group the bus is running as.
*
* @param user the user to become
* @param error return location for errors
* @returns #FALSE on failure
*/
dbus_bool_t
_dbus_change_to_daemon_user (const char *user,
DBusError *error)
{
dbus_uid_t uid;
dbus_gid_t gid;
DBusString u;
_dbus_string_init_const (&u, user);
if (!_dbus_get_user_id_and_primary_group (&u, &uid, &gid))
{
dbus_set_error (error, DBUS_ERROR_FAILED,
"User '%s' does not appear to exist?",
user);
return FALSE;
}
/* If we were root */
if (_dbus_geteuid () == 0)
{
int rc;
capng_clear (CAPNG_SELECT_BOTH);
capng_update (CAPNG_ADD, CAPNG_EFFECTIVE | CAPNG_PERMITTED,
CAP_AUDIT_WRITE);
rc = capng_change_id (uid, gid, CAPNG_DROP_SUPP_GRP);
if (rc)
{
switch (rc) {
default:
dbus_set_error (error, DBUS_ERROR_FAILED,
"Failed to drop capabilities: %s\n",
_dbus_strerror (errno));
break;
case -4:
dbus_set_error (error, _dbus_error_from_errno (errno),
"Failed to set GID to %lu: %s", gid,
_dbus_strerror (errno));
break;
case -5:
_dbus_warn ("Failed to drop supplementary groups: %s\n",
_dbus_strerror (errno));
break;
case -6:
dbus_set_error (error, _dbus_error_from_errno (errno),
"Failed to set UID to %lu: %s", uid,
_dbus_strerror (errno));
break;
case -7:
dbus_set_error (error, _dbus_error_from_errno (errno),
"Failed to unset keep-capabilities: %s\n",
_dbus_strerror (errno));
break;
}
return FALSE;
}
}
return TRUE;
}
#endif