freebsd-skq/sys/security/mac/mac_inet.c
rwatson 849a8ce20b Continue work to optimize performance of "options MAC" when no MAC policy
modules are loaded by avoiding mbuf label lookups when policies aren't
loaded, pushing further socket locking into MAC policy modules, and
avoiding locking MAC ifnet locks when no policies are loaded:

- Check mac_policies_count before looking for mbuf MAC label m_tags in MAC
  Framework entry points.  We will still pay label lookup costs if MAC
  policies are present but don't require labels (typically a single mbuf
  header field read, but perhaps further indirection if IPSEC or other
  m_tag consumers are in use).

- Further push socket locking for socket-related access control checks and
  events into MAC policies from the MAC Framework, so that sockets are
  only locked if a policy specifically requires a lock to protect a label.
  This resolves lock order issues during sonewconn() and also in local
  domain socket cross-connect where multiple socket locks could not be
  held at once for the purposes of propagatig MAC labels across multiple
  sockets.  Eliminate mac_policy_count check in some entry points where it
  no longer avoids locking.

- Add mac_policy_count checking in some entry points relating to network
  interfaces that otherwise lock a global MAC ifnet lock used to protect
  ifnet labels.

Obtained from:	TrustedBSD Project
2009-06-03 18:46:28 +00:00

509 lines
11 KiB
C

/*-
* Copyright (c) 1999-2002, 2007, 2009 Robert N. M. Watson
* Copyright (c) 2001 Ilmar S. Habibulin
* Copyright (c) 2001-2004 Networks Associates Technology, Inc.
* Copyright (c) 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 Network
* Associates Laboratories, the Security 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_kdtrace.h"
#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/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/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>
static struct label *
mac_inpcb_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(inpcb_init_label, label, flag);
else
MAC_POLICY_CHECK_NOSLEEP(inpcb_init_label, label, flag);
if (error) {
MAC_POLICY_PERFORM_NOSLEEP(inpcb_destroy_label, label);
mac_labelzone_free(label);
return (NULL);
}
return (label);
}
int
mac_inpcb_init(struct inpcb *inp, int flag)
{
if (mac_labeled & MPC_OBJECT_INPCB) {
inp->inp_label = mac_inpcb_label_alloc(flag);
if (inp->inp_label == NULL)
return (ENOMEM);
} else
inp->inp_label = NULL;
return (0);
}
static struct label *
mac_ipq_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(ipq_init_label, label, flag);
else
MAC_POLICY_CHECK_NOSLEEP(ipq_init_label, label, flag);
if (error) {
MAC_POLICY_PERFORM_NOSLEEP(ipq_destroy_label, label);
mac_labelzone_free(label);
return (NULL);
}
return (label);
}
int
mac_ipq_init(struct ipq *q, int flag)
{
if (mac_labeled & MPC_OBJECT_IPQ) {
q->ipq_label = mac_ipq_label_alloc(flag);
if (q->ipq_label == NULL)
return (ENOMEM);
} else
q->ipq_label = NULL;
return (0);
}
static void
mac_inpcb_label_free(struct label *label)
{
MAC_POLICY_PERFORM_NOSLEEP(inpcb_destroy_label, label);
mac_labelzone_free(label);
}
void
mac_inpcb_destroy(struct inpcb *inp)
{
if (inp->inp_label != NULL) {
mac_inpcb_label_free(inp->inp_label);
inp->inp_label = NULL;
}
}
static void
mac_ipq_label_free(struct label *label)
{
MAC_POLICY_PERFORM_NOSLEEP(ipq_destroy_label, label);
mac_labelzone_free(label);
}
void
mac_ipq_destroy(struct ipq *q)
{
if (q->ipq_label != NULL) {
mac_ipq_label_free(q->ipq_label);
q->ipq_label = NULL;
}
}
void
mac_inpcb_create(struct socket *so, struct inpcb *inp)
{
MAC_POLICY_PERFORM_NOSLEEP(inpcb_create, so, so->so_label, inp,
inp->inp_label);
}
void
mac_ipq_reassemble(struct ipq *q, struct mbuf *m)
{
struct label *label;
if (mac_policy_count == 0)
return;
label = mac_mbuf_to_label(m);
MAC_POLICY_PERFORM_NOSLEEP(ipq_reassemble, q, q->ipq_label, m,
label);
}
void
mac_netinet_fragment(struct mbuf *m, struct mbuf *frag)
{
struct label *mlabel, *fraglabel;
if (mac_policy_count == 0)
return;
mlabel = mac_mbuf_to_label(m);
fraglabel = mac_mbuf_to_label(frag);
MAC_POLICY_PERFORM_NOSLEEP(netinet_fragment, m, mlabel, frag,
fraglabel);
}
void
mac_ipq_create(struct mbuf *m, struct ipq *q)
{
struct label *label;
if (mac_policy_count == 0)
return;
label = mac_mbuf_to_label(m);
MAC_POLICY_PERFORM_NOSLEEP(ipq_create, m, label, q, q->ipq_label);
}
void
mac_inpcb_create_mbuf(struct inpcb *inp, struct mbuf *m)
{
struct label *mlabel;
INP_LOCK_ASSERT(inp);
if (mac_policy_count == 0)
return;
mlabel = mac_mbuf_to_label(m);
MAC_POLICY_PERFORM_NOSLEEP(inpcb_create_mbuf, inp, inp->inp_label, m,
mlabel);
}
int
mac_ipq_match(struct mbuf *m, struct ipq *q)
{
struct label *label;
int result;
if (mac_policy_count == 0)
return (1);
label = mac_mbuf_to_label(m);
result = 1;
MAC_POLICY_BOOLEAN_NOSLEEP(ipq_match, &&, m, label, q, q->ipq_label);
return (result);
}
void
mac_netinet_arp_send(struct ifnet *ifp, struct mbuf *m)
{
struct label *mlabel;
if (mac_policy_count == 0)
return;
mlabel = mac_mbuf_to_label(m);
MAC_IFNET_LOCK(ifp);
MAC_POLICY_PERFORM_NOSLEEP(netinet_arp_send, ifp, ifp->if_label, m,
mlabel);
MAC_IFNET_UNLOCK(ifp);
}
void
mac_netinet_icmp_reply(struct mbuf *mrecv, struct mbuf *msend)
{
struct label *mrecvlabel, *msendlabel;
if (mac_policy_count == 0)
return;
mrecvlabel = mac_mbuf_to_label(mrecv);
msendlabel = mac_mbuf_to_label(msend);
MAC_POLICY_PERFORM_NOSLEEP(netinet_icmp_reply, mrecv, mrecvlabel,
msend, msendlabel);
}
void
mac_netinet_icmp_replyinplace(struct mbuf *m)
{
struct label *label;
if (mac_policy_count == 0)
return;
label = mac_mbuf_to_label(m);
MAC_POLICY_PERFORM_NOSLEEP(netinet_icmp_replyinplace, m, label);
}
void
mac_netinet_igmp_send(struct ifnet *ifp, struct mbuf *m)
{
struct label *mlabel;
if (mac_policy_count == 0)
return;
mlabel = mac_mbuf_to_label(m);
MAC_IFNET_LOCK(ifp);
MAC_POLICY_PERFORM_NOSLEEP(netinet_igmp_send, ifp, ifp->if_label, m,
mlabel);
MAC_IFNET_UNLOCK(ifp);
}
void
mac_netinet_tcp_reply(struct mbuf *m)
{
struct label *label;
if (mac_policy_count == 0)
return;
label = mac_mbuf_to_label(m);
MAC_POLICY_PERFORM_NOSLEEP(netinet_tcp_reply, m, label);
}
void
mac_ipq_update(struct mbuf *m, struct ipq *q)
{
struct label *label;
if (mac_policy_count == 0)
return;
label = mac_mbuf_to_label(m);
MAC_POLICY_PERFORM_NOSLEEP(ipq_update, m, label, q, q->ipq_label);
}
MAC_CHECK_PROBE_DEFINE2(inpcb_check_deliver, "struct inpcb *",
"struct mbuf *");
int
mac_inpcb_check_deliver(struct inpcb *inp, struct mbuf *m)
{
struct label *label;
int error;
M_ASSERTPKTHDR(m);
if (mac_policy_count == 0)
return (0);
label = mac_mbuf_to_label(m);
MAC_POLICY_CHECK_NOSLEEP(inpcb_check_deliver, inp, inp->inp_label, m,
label);
MAC_CHECK_PROBE2(inpcb_check_deliver, error, inp, m);
return (error);
}
MAC_CHECK_PROBE_DEFINE2(inpcb_check_visible, "struct ucred *",
"struct inpcb *");
int
mac_inpcb_check_visible(struct ucred *cred, struct inpcb *inp)
{
int error;
INP_LOCK_ASSERT(inp);
MAC_POLICY_CHECK_NOSLEEP(inpcb_check_visible, cred, inp,
inp->inp_label);
MAC_CHECK_PROBE2(inpcb_check_visible, error, cred, inp);
return (error);
}
void
mac_inpcb_sosetlabel(struct socket *so, struct inpcb *inp)
{
INP_WLOCK_ASSERT(inp);
SOCK_LOCK_ASSERT(so);
MAC_POLICY_PERFORM_NOSLEEP(inpcb_sosetlabel, so, so->so_label, inp,
inp->inp_label);
}
void
mac_netinet_firewall_reply(struct mbuf *mrecv, struct mbuf *msend)
{
struct label *mrecvlabel, *msendlabel;
M_ASSERTPKTHDR(mrecv);
M_ASSERTPKTHDR(msend);
if (mac_policy_count == 0)
return;
mrecvlabel = mac_mbuf_to_label(mrecv);
msendlabel = mac_mbuf_to_label(msend);
MAC_POLICY_PERFORM_NOSLEEP(netinet_firewall_reply, mrecv, mrecvlabel,
msend, msendlabel);
}
void
mac_netinet_firewall_send(struct mbuf *m)
{
struct label *label;
M_ASSERTPKTHDR(m);
if (mac_policy_count == 0)
return;
label = mac_mbuf_to_label(m);
MAC_POLICY_PERFORM_NOSLEEP(netinet_firewall_send, m, label);
}
/*
* These functions really should be referencing the syncache structure
* instead of the label. However, due to some of the complexities associated
* with exposing this syncache structure we operate directly on it's label
* pointer. This should be OK since we aren't making any access control
* decisions within this code directly, we are merely allocating and copying
* label storage so we can properly initialize mbuf labels for any packets
* the syncache code might create.
*/
void
mac_syncache_destroy(struct label **label)
{
if (*label != NULL) {
MAC_POLICY_PERFORM_NOSLEEP(syncache_destroy_label, *label);
mac_labelzone_free(*label);
*label = NULL;
}
}
int
mac_syncache_init(struct label **label)
{
int error;
if (mac_labeled & MPC_OBJECT_SYNCACHE) {
*label = mac_labelzone_alloc(M_NOWAIT);
if (*label == NULL)
return (ENOMEM);
/*
* Since we are holding the inpcb locks the policy can not
* allocate policy specific label storage using M_WAITOK. So
* we need to do a MAC_CHECK instead of the typical
* MAC_PERFORM so we can propagate allocation failures back
* to the syncache code.
*/
MAC_POLICY_CHECK_NOSLEEP(syncache_init_label, *label,
M_NOWAIT);
if (error) {
MAC_POLICY_PERFORM_NOSLEEP(syncache_destroy_label,
*label);
mac_labelzone_free(*label);
}
return (error);
} else
*label = NULL;
return (0);
}
void
mac_syncache_create(struct label *label, struct inpcb *inp)
{
INP_WLOCK_ASSERT(inp);
MAC_POLICY_PERFORM_NOSLEEP(syncache_create, label, inp);
}
void
mac_syncache_create_mbuf(struct label *sc_label, struct mbuf *m)
{
struct label *mlabel;
M_ASSERTPKTHDR(m);
if (mac_policy_count == 0)
return;
mlabel = mac_mbuf_to_label(m);
MAC_POLICY_PERFORM_NOSLEEP(syncache_create_mbuf, sc_label, m,
mlabel);
}