freebsd-dev/sys/security/mac/mac_socket.c
Attilio Rao 54366c0bd7 - For kernel compiled only with KDTRACE_HOOKS and not any lock debugging
option, unbreak the lock tracing release semantic by embedding
  calls to LOCKSTAT_PROFILE_RELEASE_LOCK() direclty in the inlined
  version of the releasing functions for mutex, rwlock and sxlock.
  Failing to do so skips the lockstat_probe_func invokation for
  unlocking.
- As part of the LOCKSTAT support is inlined in mutex operation, for
  kernel compiled without lock debugging options, potentially every
  consumer must be compiled including opt_kdtrace.h.
  Fix this by moving KDTRACE_HOOKS into opt_global.h and remove the
  dependency by opt_kdtrace.h for all files, as now only KDTRACE_FRAMES
  is linked there and it is only used as a compile-time stub [0].

[0] immediately shows some new bug as DTRACE-derived support for debug
in sfxge is broken and it was never really tested.  As it was not
including correctly opt_kdtrace.h before it was never enabled so it
was kept broken for a while.  Fix this by using a protection stub,
leaving sfxge driver authors the responsibility for fixing it
appropriately [1].

Sponsored by:	EMC / Isilon storage division
Discussed with:	rstone
[0] Reported by:	rstone
[1] Discussed with:	philip
2013-11-25 07:38:45 +00:00

634 lines
15 KiB
C

/*-
* Copyright (c) 1999-2002, 2009 Robert N. M. Watson
* Copyright (c) 2001 Ilmar S. Habibulin
* Copyright (c) 2001-2005 Networks Associates Technology, Inc.
* Copyright (c) 2005-2006 SPARTA, Inc.
* Copyright (c) 2008 Apple Inc.
* All rights reserved.
*
* This software was developed by Robert Watson and Ilmar Habibulin for the
* TrustedBSD Project.
*
* This software was developed for the FreeBSD Project in part by McAfee
* Research, the Technology Research Division of Network Associates, Inc.
* under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
* DARPA CHATS research program.
*
* This software was enhanced by SPARTA ISSO under SPAWAR contract
* N66001-04-C-6019 ("SEFOS").
*
* This software was developed at the University of Cambridge Computer
* Laboratory with support from a grant from Google, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_mac.h"
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mutex.h>
#include <sys/mac.h>
#include <sys/sbuf.h>
#include <sys/sdt.h>
#include <sys/systm.h>
#include <sys/mount.h>
#include <sys/file.h>
#include <sys/namei.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sysctl.h>
#include <net/bpfdesc.h>
#include <net/if.h>
#include <net/if_var.h>
#include <netinet/in.h>
#include <netinet/in_pcb.h>
#include <netinet/ip_var.h>
#include <security/mac/mac_framework.h>
#include <security/mac/mac_internal.h>
#include <security/mac/mac_policy.h>
/*
* Currently, sockets hold two labels: the label of the socket itself, and a
* peer label, which may be used by policies to hold a copy of the label of
* any remote endpoint.
*
* Possibly, this peer label should be maintained at the protocol layer
* (inpcb, unpcb, etc), as this would allow protocol-aware code to maintain
* the label consistently. For example, it might be copied live from a
* remote socket for UNIX domain sockets rather than keeping a local copy on
* this endpoint, but be cached and updated based on packets received for
* TCP/IP.
*
* Unlike with many other object types, the lock protecting MAC labels on
* sockets (the socket lock) is not frequently held at the points in code
* where socket-related checks are called. The MAC Framework acquires the
* lock over some entry points in order to enforce atomicity (such as label
* copies) but in other cases the policy modules will have to acquire the
* lock themselves if they use labels. This approach (a) avoids lock
* acquisitions when policies don't require labels and (b) solves a number of
* potential lock order issues when multiple sockets are used in the same
* entry point.
*/
struct label *
mac_socket_label_alloc(int flag)
{
struct label *label;
int error;
label = mac_labelzone_alloc(flag);
if (label == NULL)
return (NULL);
if (flag & M_WAITOK)
MAC_POLICY_CHECK(socket_init_label, label, flag);
else
MAC_POLICY_CHECK_NOSLEEP(socket_init_label, label, flag);
if (error) {
MAC_POLICY_PERFORM_NOSLEEP(socket_destroy_label, label);
mac_labelzone_free(label);
return (NULL);
}
return (label);
}
static struct label *
mac_socketpeer_label_alloc(int flag)
{
struct label *label;
int error;
label = mac_labelzone_alloc(flag);
if (label == NULL)
return (NULL);
if (flag & M_WAITOK)
MAC_POLICY_CHECK(socketpeer_init_label, label, flag);
else
MAC_POLICY_CHECK_NOSLEEP(socketpeer_init_label, label, flag);
if (error) {
MAC_POLICY_PERFORM_NOSLEEP(socketpeer_destroy_label, label);
mac_labelzone_free(label);
return (NULL);
}
return (label);
}
int
mac_socket_init(struct socket *so, int flag)
{
if (mac_labeled & MPC_OBJECT_SOCKET) {
so->so_label = mac_socket_label_alloc(flag);
if (so->so_label == NULL)
return (ENOMEM);
so->so_peerlabel = mac_socketpeer_label_alloc(flag);
if (so->so_peerlabel == NULL) {
mac_socket_label_free(so->so_label);
so->so_label = NULL;
return (ENOMEM);
}
} else {
so->so_label = NULL;
so->so_peerlabel = NULL;
}
return (0);
}
void
mac_socket_label_free(struct label *label)
{
MAC_POLICY_PERFORM_NOSLEEP(socket_destroy_label, label);
mac_labelzone_free(label);
}
static void
mac_socketpeer_label_free(struct label *label)
{
MAC_POLICY_PERFORM_NOSLEEP(socketpeer_destroy_label, label);
mac_labelzone_free(label);
}
void
mac_socket_destroy(struct socket *so)
{
if (so->so_label != NULL) {
mac_socket_label_free(so->so_label);
so->so_label = NULL;
mac_socketpeer_label_free(so->so_peerlabel);
so->so_peerlabel = NULL;
}
}
void
mac_socket_copy_label(struct label *src, struct label *dest)
{
MAC_POLICY_PERFORM_NOSLEEP(socket_copy_label, src, dest);
}
int
mac_socket_externalize_label(struct label *label, char *elements,
char *outbuf, size_t outbuflen)
{
int error;
MAC_POLICY_EXTERNALIZE(socket, label, elements, outbuf, outbuflen);
return (error);
}
static int
mac_socketpeer_externalize_label(struct label *label, char *elements,
char *outbuf, size_t outbuflen)
{
int error;
MAC_POLICY_EXTERNALIZE(socketpeer, label, elements, outbuf,
outbuflen);
return (error);
}
int
mac_socket_internalize_label(struct label *label, char *string)
{
int error;
MAC_POLICY_INTERNALIZE(socket, label, string);
return (error);
}
void
mac_socket_create(struct ucred *cred, struct socket *so)
{
MAC_POLICY_PERFORM_NOSLEEP(socket_create, cred, so, so->so_label);
}
void
mac_socket_newconn(struct socket *oldso, struct socket *newso)
{
MAC_POLICY_PERFORM_NOSLEEP(socket_newconn, oldso, oldso->so_label,
newso, newso->so_label);
}
static void
mac_socket_relabel(struct ucred *cred, struct socket *so,
struct label *newlabel)
{
SOCK_LOCK_ASSERT(so);
MAC_POLICY_PERFORM_NOSLEEP(socket_relabel, cred, so, so->so_label,
newlabel);
}
void
mac_socketpeer_set_from_mbuf(struct mbuf *m, struct socket *so)
{
struct label *label;
if (mac_policy_count == 0)
return;
label = mac_mbuf_to_label(m);
MAC_POLICY_PERFORM_NOSLEEP(socketpeer_set_from_mbuf, m, label, so,
so->so_peerlabel);
}
void
mac_socketpeer_set_from_socket(struct socket *oldso, struct socket *newso)
{
if (mac_policy_count == 0)
return;
MAC_POLICY_PERFORM_NOSLEEP(socketpeer_set_from_socket, oldso,
oldso->so_label, newso, newso->so_peerlabel);
}
void
mac_socket_create_mbuf(struct socket *so, struct mbuf *m)
{
struct label *label;
if (mac_policy_count == 0)
return;
label = mac_mbuf_to_label(m);
MAC_POLICY_PERFORM_NOSLEEP(socket_create_mbuf, so, so->so_label, m,
label);
}
MAC_CHECK_PROBE_DEFINE2(socket_check_accept, "struct ucred *",
"struct socket *");
int
mac_socket_check_accept(struct ucred *cred, struct socket *so)
{
int error;
MAC_POLICY_CHECK_NOSLEEP(socket_check_accept, cred, so,
so->so_label);
MAC_CHECK_PROBE2(socket_check_accept, error, cred, so);
return (error);
}
MAC_CHECK_PROBE_DEFINE3(socket_check_bind, "struct ucred *",
"struct socket *", "struct sockaddr *");
int
mac_socket_check_bind(struct ucred *cred, struct socket *so,
struct sockaddr *sa)
{
int error;
MAC_POLICY_CHECK_NOSLEEP(socket_check_bind, cred, so, so->so_label,
sa);
MAC_CHECK_PROBE3(socket_check_bind, error, cred, so, sa);
return (error);
}
MAC_CHECK_PROBE_DEFINE3(socket_check_connect, "struct ucred *",
"struct socket *", "struct sockaddr *");
int
mac_socket_check_connect(struct ucred *cred, struct socket *so,
struct sockaddr *sa)
{
int error;
MAC_POLICY_CHECK_NOSLEEP(socket_check_connect, cred, so,
so->so_label, sa);
MAC_CHECK_PROBE3(socket_check_connect, error, cred, so, sa);
return (error);
}
MAC_CHECK_PROBE_DEFINE4(socket_check_create, "struct ucred *", "int", "int",
"int");
int
mac_socket_check_create(struct ucred *cred, int domain, int type, int proto)
{
int error;
MAC_POLICY_CHECK_NOSLEEP(socket_check_create, cred, domain, type,
proto);
MAC_CHECK_PROBE4(socket_check_create, error, cred, domain, type,
proto);
return (error);
}
MAC_CHECK_PROBE_DEFINE2(socket_check_deliver, "struct socket *",
"struct mbuf *");
int
mac_socket_check_deliver(struct socket *so, struct mbuf *m)
{
struct label *label;
int error;
if (mac_policy_count == 0)
return (0);
label = mac_mbuf_to_label(m);
MAC_POLICY_CHECK_NOSLEEP(socket_check_deliver, so, so->so_label, m,
label);
MAC_CHECK_PROBE2(socket_check_deliver, error, so, m);
return (error);
}
MAC_CHECK_PROBE_DEFINE2(socket_check_listen, "struct ucred *",
"struct socket *");
int
mac_socket_check_listen(struct ucred *cred, struct socket *so)
{
int error;
MAC_POLICY_CHECK_NOSLEEP(socket_check_listen, cred, so,
so->so_label);
MAC_CHECK_PROBE2(socket_check_listen, error, cred, so);
return (error);
}
MAC_CHECK_PROBE_DEFINE2(socket_check_poll, "struct ucred *",
"struct socket *");
int
mac_socket_check_poll(struct ucred *cred, struct socket *so)
{
int error;
MAC_POLICY_CHECK_NOSLEEP(socket_check_poll, cred, so, so->so_label);
MAC_CHECK_PROBE2(socket_check_poll, error, cred, so);
return (error);
}
MAC_CHECK_PROBE_DEFINE2(socket_check_receive, "struct ucred *",
"struct socket *");
int
mac_socket_check_receive(struct ucred *cred, struct socket *so)
{
int error;
MAC_POLICY_CHECK_NOSLEEP(socket_check_receive, cred, so,
so->so_label);
MAC_CHECK_PROBE2(socket_check_receive, error, cred, so);
return (error);
}
MAC_CHECK_PROBE_DEFINE3(socket_check_relabel, "struct ucred *",
"struct socket *", "struct label *");
static int
mac_socket_check_relabel(struct ucred *cred, struct socket *so,
struct label *newlabel)
{
int error;
SOCK_LOCK_ASSERT(so);
MAC_POLICY_CHECK_NOSLEEP(socket_check_relabel, cred, so,
so->so_label, newlabel);
MAC_CHECK_PROBE3(socket_check_relabel, error, cred, so, newlabel);
return (error);
}
MAC_CHECK_PROBE_DEFINE2(socket_check_send, "struct ucred *",
"struct socket *");
int
mac_socket_check_send(struct ucred *cred, struct socket *so)
{
int error;
MAC_POLICY_CHECK_NOSLEEP(socket_check_send, cred, so, so->so_label);
MAC_CHECK_PROBE2(socket_check_send, error, cred, so);
return (error);
}
MAC_CHECK_PROBE_DEFINE2(socket_check_stat, "struct ucred *",
"struct socket *");
int
mac_socket_check_stat(struct ucred *cred, struct socket *so)
{
int error;
MAC_POLICY_CHECK_NOSLEEP(socket_check_stat, cred, so, so->so_label);
MAC_CHECK_PROBE2(socket_check_stat, error, cred, so);
return (error);
}
MAC_CHECK_PROBE_DEFINE2(socket_check_visible, "struct ucred *",
"struct socket *");
int
mac_socket_check_visible(struct ucred *cred, struct socket *so)
{
int error;
MAC_POLICY_CHECK_NOSLEEP(socket_check_visible, cred, so,
so->so_label);
MAC_CHECK_PROBE2(socket_check_visible, error, cred, so);
return (error);
}
int
mac_socket_label_set(struct ucred *cred, struct socket *so,
struct label *label)
{
int error;
/*
* We acquire the socket lock when we perform the test and set, but
* have to release it as the pcb code needs to acquire the pcb lock,
* which will precede the socket lock in the lock order. However,
* this is fine, as any race will simply result in the inpcb being
* refreshed twice, but still consistently, as the inpcb code will
* acquire the socket lock before refreshing, holding both locks.
*/
SOCK_LOCK(so);
error = mac_socket_check_relabel(cred, so, label);
if (error) {
SOCK_UNLOCK(so);
return (error);
}
mac_socket_relabel(cred, so, label);
SOCK_UNLOCK(so);
/*
* If the protocol has expressed interest in socket layer changes,
* such as if it needs to propagate changes to a cached pcb label
* from the socket, notify it of the label change while holding the
* socket lock.
*/
if (so->so_proto->pr_usrreqs->pru_sosetlabel != NULL)
(so->so_proto->pr_usrreqs->pru_sosetlabel)(so);
return (0);
}
int
mac_setsockopt_label(struct ucred *cred, struct socket *so, struct mac *mac)
{
struct label *intlabel;
char *buffer;
int error;
if (!(mac_labeled & MPC_OBJECT_SOCKET))
return (EINVAL);
error = mac_check_structmac_consistent(mac);
if (error)
return (error);
buffer = malloc(mac->m_buflen, M_MACTEMP, M_WAITOK);
error = copyinstr(mac->m_string, buffer, mac->m_buflen, NULL);
if (error) {
free(buffer, M_MACTEMP);
return (error);
}
intlabel = mac_socket_label_alloc(M_WAITOK);
error = mac_socket_internalize_label(intlabel, buffer);
free(buffer, M_MACTEMP);
if (error)
goto out;
error = mac_socket_label_set(cred, so, intlabel);
out:
mac_socket_label_free(intlabel);
return (error);
}
int
mac_getsockopt_label(struct ucred *cred, struct socket *so, struct mac *mac)
{
char *buffer, *elements;
struct label *intlabel;
int error;
if (!(mac_labeled & MPC_OBJECT_SOCKET))
return (EINVAL);
error = mac_check_structmac_consistent(mac);
if (error)
return (error);
elements = malloc(mac->m_buflen, M_MACTEMP, M_WAITOK);
error = copyinstr(mac->m_string, elements, mac->m_buflen, NULL);
if (error) {
free(elements, M_MACTEMP);
return (error);
}
buffer = malloc(mac->m_buflen, M_MACTEMP, M_WAITOK | M_ZERO);
intlabel = mac_socket_label_alloc(M_WAITOK);
SOCK_LOCK(so);
mac_socket_copy_label(so->so_label, intlabel);
SOCK_UNLOCK(so);
error = mac_socket_externalize_label(intlabel, elements, buffer,
mac->m_buflen);
mac_socket_label_free(intlabel);
if (error == 0)
error = copyout(buffer, mac->m_string, strlen(buffer)+1);
free(buffer, M_MACTEMP);
free(elements, M_MACTEMP);
return (error);
}
int
mac_getsockopt_peerlabel(struct ucred *cred, struct socket *so,
struct mac *mac)
{
char *elements, *buffer;
struct label *intlabel;
int error;
if (!(mac_labeled & MPC_OBJECT_SOCKET))
return (EINVAL);
error = mac_check_structmac_consistent(mac);
if (error)
return (error);
elements = malloc(mac->m_buflen, M_MACTEMP, M_WAITOK);
error = copyinstr(mac->m_string, elements, mac->m_buflen, NULL);
if (error) {
free(elements, M_MACTEMP);
return (error);
}
buffer = malloc(mac->m_buflen, M_MACTEMP, M_WAITOK | M_ZERO);
intlabel = mac_socket_label_alloc(M_WAITOK);
SOCK_LOCK(so);
mac_socket_copy_label(so->so_peerlabel, intlabel);
SOCK_UNLOCK(so);
error = mac_socketpeer_externalize_label(intlabel, elements, buffer,
mac->m_buflen);
mac_socket_label_free(intlabel);
if (error == 0)
error = copyout(buffer, mac->m_string, strlen(buffer)+1);
free(buffer, M_MACTEMP);
free(elements, M_MACTEMP);
return (error);
}