diff options
Diffstat (limited to 'sys/security/mac_ifoff/mac_ifoff.c')
| -rw-r--r-- | sys/security/mac_ifoff/mac_ifoff.c | 173 |
1 files changed, 173 insertions, 0 deletions
diff --git a/sys/security/mac_ifoff/mac_ifoff.c b/sys/security/mac_ifoff/mac_ifoff.c new file mode 100644 index 000000000000..b43bb1a592c1 --- /dev/null +++ b/sys/security/mac_ifoff/mac_ifoff.c @@ -0,0 +1,173 @@ +/*- + * Copyright (c) 1999, 2000, 2001, 2002 Robert N. M. Watson + * Copyright (c) 2001, 2002 Networks Associates Technology, Inc. + * All rights reserved. + * + * This software was developed by Robert Watson for the TrustedBSD Project. + * + * This software was developed for the FreeBSD Project in part by NAI Labs, + * 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. + * + * 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. + * 3. The names of the authors may not be used to endorse or promote + * products derived from this software without specific prior written + * permission. + * + * 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. + * + * $FreeBSD$ + */ + +/* + * Developed by the TrustedBSD Project. + * Limit access to interfaces until they are specifically administratively + * enabled. Prevents protocol stack-driven packet leakage in unsafe + * environments. + */ + +#include <sys/types.h> +#include <sys/param.h> +#include <sys/conf.h> +#include <sys/kernel.h> +#include <sys/mac.h> +#include <sys/mount.h> +#include <sys/proc.h> +#include <sys/systm.h> +#include <sys/sysproto.h> +#include <sys/sysent.h> +#include <sys/vnode.h> +#include <sys/file.h> +#include <sys/socket.h> +#include <sys/socketvar.h> +#include <sys/sysctl.h> + +#include <net/bpfdesc.h> +#include <net/if.h> +#include <net/if_types.h> +#include <net/if_var.h> + +#include <vm/vm.h> + +#include <sys/mac_policy.h> + +SYSCTL_DECL(_security_mac); + +SYSCTL_NODE(_security_mac, OID_AUTO, ifoff, CTLFLAG_RW, 0, + "TrustedBSD mac_ifoff policy controls"); + +static int mac_ifoff_enabled = 1; +SYSCTL_INT(_security_mac_ifoff, OID_AUTO, enabled, CTLFLAG_RW, + &mac_ifoff_enabled, 0, "Enforce ifoff policy"); +TUNABLE_INT("security.mac.ifoff.enabled", &mac_ifoff_enabled); + +static int mac_ifoff_lo_enabled = 1; +SYSCTL_INT(_security_mac_ifoff, OID_AUTO, lo_enabled, CTLFLAG_RW, + &mac_ifoff_lo_enabled, 0, "Enable loopback interfaces"); +TUNABLE_INT("security.mac.ifoff.lo_enabled", &mac_ifoff_lo_enabled); + +static int mac_ifoff_other_enabled = 0; +SYSCTL_INT(_security_mac_ifoff, OID_AUTO, other_enabled, CTLFLAG_RW, + &mac_ifoff_other_enabled, 0, "Enable other interfaces"); +TUNABLE_INT("security.mac.ifoff.other_enabled", &mac_ifoff_other_enabled); + +static int mac_ifoff_bpfrecv_enabled = 0; +SYSCTL_INT(_security_mac_ifoff, OID_AUTO, bpfrecv_enabled, CTLFLAG_RW, + &mac_ifoff_bpfrecv_enabled, 0, "Enable BPF reception even when interface " + "is disabled"); +TUNABLE_INT("security.mac.ifoff.bpfrecv.enabled", &mac_ifoff_bpfrecv_enabled); + +static int +check_ifnet_outgoing(struct ifnet *ifnet) +{ + + if (!mac_ifoff_enabled) + return (0); + + if (mac_ifoff_lo_enabled && ifnet->if_type == IFT_LOOP) + return (0); + + if (mac_ifoff_other_enabled && ifnet->if_type != IFT_LOOP) + return (0); + + return (EPERM); +} + +static int +check_ifnet_incoming(struct ifnet *ifnet, int viabpf) +{ + if (!mac_ifoff_enabled) + return (0); + + if (mac_ifoff_lo_enabled && ifnet->if_type == IFT_LOOP) + return (0); + + if (mac_ifoff_other_enabled && ifnet->if_type != IFT_LOOP) + return (0); + + if (viabpf && mac_ifoff_bpfrecv_enabled) + return (0); + + return (EPERM); +} + +static int +mac_ifoff_check_bpfdesc_receive(struct bpf_d *bpf_d, struct label *bpflabel, + struct ifnet *ifnet, struct label *ifnetlabel) +{ + + return (check_ifnet_incoming(ifnet, 1)); +} + +static int +mac_ifoff_check_ifnet_transmit(struct ifnet *ifnet, struct label *ifnetlabel, + struct mbuf *m, struct label *mbuflabel) +{ + + return (check_ifnet_outgoing(ifnet)); +} + +static int +mac_ifoff_check_socket_receive(struct socket *so, struct label *socketlabel, + struct mbuf *m, struct label *mbuflabel) +{ + + if (m->m_flags & M_PKTHDR) { + if (m->m_pkthdr.rcvif != NULL) + return (check_ifnet_incoming(m->m_pkthdr.rcvif, 0)); + } + + return (0); +} + +static struct mac_policy_op_entry mac_ifoff_ops[] = +{ + { MAC_CHECK_BPFDESC_RECEIVE, + (macop_t)mac_ifoff_check_bpfdesc_receive }, + { MAC_CHECK_IFNET_TRANSMIT, + (macop_t)mac_ifoff_check_ifnet_transmit }, + { MAC_CHECK_SOCKET_RECEIVE, + (macop_t)mac_ifoff_check_socket_receive }, + { MAC_OP_LAST, NULL } +}; + +MAC_POLICY_SET(mac_ifoff_ops, trustedbsd_mac_ifoff, "TrustedBSD MAC/ifoff", + MPC_LOADTIME_FLAG_UNLOADOK, NULL); |