d/freebsd-dev
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
9837f3e457
freebsd-dev/sys/net/if_ethersubr.c
Oleg Bulyzhin dda10d624c Close long existed race with net.inet.ip.fw.one_pass = 0: 
If packet leaves ipfw to other kernel subsystem (dummynet, netgraph, etc)
it carries pointer to matching ipfw rule. If this packet then reinjected back
to ipfw, ruleset processing starts from that rule. If rule was deleted
meanwhile, due to existed race condition panic was possible (as well as
other odd effects like parsing rules in 'reap list').

P.S. this commit changes ABI so userland ipfw related binaries should be
recompiled.

MFC after:	1 month
Tested by:	Mikolaj Golub
2009-06-09 21:27:11 +00:00

1336 lines
33 KiB
C
Raw Blame History

/*-
* Copyright (c) 1982, 1989, 1993
* The Regents of the University of California. All rights reserved.
*
* 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.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
*
* @(#)if_ethersubr.c 8.1 (Berkeley) 6/10/93
* $FreeBSD$
*/
#include "opt_atalk.h"
#include "opt_inet.h"
#include "opt_inet6.h"
#include "opt_ipx.h"
#include "opt_netgraph.h"
#include "opt_carp.h"
#include "opt_mbuf_profiling.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/module.h>
#include <sys/mbuf.h>
#include <sys/random.h>
#include <sys/rwlock.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <sys/sysctl.h>
#include <sys/vimage.h>
#include <net/if.h>
#include <net/if_arp.h>
#include <net/netisr.h>
#include <net/route.h>
#include <net/if_llc.h>
#include <net/if_dl.h>
#include <net/if_types.h>
#include <net/bpf.h>
#include <net/ethernet.h>
#include <net/if_bridgevar.h>
#include <net/if_vlan_var.h>
#include <net/if_llatbl.h>
#include <net/pf_mtag.h>
#include <net/vnet.h>
#if defined(INET) || defined(INET6)
#include <netinet/in.h>
#include <netinet/in_var.h>
#include <netinet/if_ether.h>
#include <netinet/ip_fw.h>
#include <netinet/ip_dummynet.h>
#include <netinet/vinet.h>
#endif
#ifdef INET6
#include <netinet6/nd6.h>
#endif
#ifdef DEV_CARP
#include <netinet/ip_carp.h>
#endif
#ifdef IPX
#include <netipx/ipx.h>
#include <netipx/ipx_if.h>
#endif
int (*ef_inputp)(struct ifnet*, struct ether_header *eh, struct mbuf *m);
int (*ef_outputp)(struct ifnet *ifp, struct mbuf **mp,
struct sockaddr *dst, short *tp, int *hlen);
#ifdef NETATALK
#include <netatalk/at.h>
#include <netatalk/at_var.h>
#include <netatalk/at_extern.h>
#define llc_snap_org_code llc_un.type_snap.org_code
#define llc_snap_ether_type llc_un.type_snap.ether_type
extern u_char at_org_code[3];
extern u_char aarp_org_code[3];
#endif /* NETATALK */
#include <security/mac/mac_framework.h>
#ifdef CTASSERT
CTASSERT(sizeof (struct ether_header) == ETHER_ADDR_LEN * 2 + 2);
CTASSERT(sizeof (struct ether_addr) == ETHER_ADDR_LEN);
#endif
/* netgraph node hooks for ng_ether(4) */
void (*ng_ether_input_p)(struct ifnet *ifp, struct mbuf **mp);
void (*ng_ether_input_orphan_p)(struct ifnet *ifp, struct mbuf *m);
int (*ng_ether_output_p)(struct ifnet *ifp, struct mbuf **mp);
void (*ng_ether_attach_p)(struct ifnet *ifp);
void (*ng_ether_detach_p)(struct ifnet *ifp);
void (*vlan_input_p)(struct ifnet *, struct mbuf *);
/* if_bridge(4) support */
struct mbuf *(*bridge_input_p)(struct ifnet *, struct mbuf *);
int (*bridge_output_p)(struct ifnet *, struct mbuf *,
struct sockaddr *, struct rtentry *);
void (*bridge_dn_p)(struct mbuf *, struct ifnet *);
/* if_lagg(4) support */
struct mbuf *(*lagg_input_p)(struct ifnet *, struct mbuf *);
static const u_char etherbroadcastaddr[ETHER_ADDR_LEN] =
{ 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
static int ether_resolvemulti(struct ifnet *, struct sockaddr **,
struct sockaddr *);
/* XXX: should be in an arp support file, not here */
MALLOC_DEFINE(M_ARPCOM, "arpcom", "802.* interface internals");
#define ETHER_IS_BROADCAST(addr) \
(bcmp(etherbroadcastaddr, (addr), ETHER_ADDR_LEN) == 0)
#define senderr(e) do { error = (e); goto bad;} while (0)
#if defined(INET) || defined(INET6)
int
ether_ipfw_chk(struct mbuf **m0, struct ifnet *dst, int shared);
#ifdef VIMAGE_GLOBALS
static int ether_ipfw;
#endif
#endif
/*
* Ethernet output routine.
* Encapsulate a packet of type family for the local net.
* Use trailer local net encapsulation if enough data in first
* packet leaves a multiple of 512 bytes of data in remainder.
*/
int
ether_output(struct ifnet *ifp, struct mbuf *m,
struct sockaddr *dst, struct route *ro)
{
short type;
int error = 0, hdrcmplt = 0;
u_char esrc[ETHER_ADDR_LEN], edst[ETHER_ADDR_LEN];
struct llentry *lle = NULL;
struct rtentry *rt0 = NULL;
struct ether_header *eh;
struct pf_mtag *t;
int loop_copy = 1;
int hlen; /* link layer header length */
if (ro != NULL) {
lle = ro->ro_lle;
rt0 = ro->ro_rt;
}
#ifdef MAC
error = mac_ifnet_check_transmit(ifp, m);
if (error)
senderr(error);
#endif
M_PROFILE(m);
if (ifp->if_flags & IFF_MONITOR)
senderr(ENETDOWN);
if (!((ifp->if_flags & IFF_UP) &&
(ifp->if_drv_flags & IFF_DRV_RUNNING)))
senderr(ENETDOWN);
hlen = ETHER_HDR_LEN;
switch (dst->sa_family) {
#ifdef INET
case AF_INET:
if (lle != NULL && (lle->la_flags & LLE_VALID))
memcpy(edst, &lle->ll_addr.mac16, sizeof(edst));
else
error = arpresolve(ifp, rt0, m, dst, edst, &lle);
if (error)
return (error == EWOULDBLOCK ? 0 : error);
type = htons(ETHERTYPE_IP);
break;
case AF_ARP:
{
struct arphdr *ah;
ah = mtod(m, struct arphdr *);
ah->ar_hrd = htons(ARPHRD_ETHER);
loop_copy = 0; /* if this is for us, don't do it */
switch(ntohs(ah->ar_op)) {
case ARPOP_REVREQUEST:
case ARPOP_REVREPLY:
type = htons(ETHERTYPE_REVARP);
break;
case ARPOP_REQUEST:
case ARPOP_REPLY:
default:
type = htons(ETHERTYPE_ARP);
break;
}
if (m->m_flags & M_BCAST)
bcopy(ifp->if_broadcastaddr, edst, ETHER_ADDR_LEN);
else
bcopy(ar_tha(ah), edst, ETHER_ADDR_LEN);
}
break;
#endif
#ifdef INET6
case AF_INET6:
if (lle != NULL && (lle->la_flags & LLE_VALID))
memcpy(edst, &lle->ll_addr.mac16, sizeof(edst));
else
error = nd6_storelladdr(ifp, m, dst, (u_char *)edst, &lle);
if (error)
return error;
type = htons(ETHERTYPE_IPV6);
break;
#endif
#ifdef IPX
case AF_IPX:
if (ef_outputp) {
error = ef_outputp(ifp, &m, dst, &type, &hlen);
if (error)
goto bad;
} else
type = htons(ETHERTYPE_IPX);
bcopy((caddr_t)&(((struct sockaddr_ipx *)dst)->sipx_addr.x_host),
(caddr_t)edst, sizeof (edst));
break;
#endif
#ifdef NETATALK
case AF_APPLETALK:
{
struct at_ifaddr *aa;
if ((aa = at_ifawithnet((struct sockaddr_at *)dst)) == NULL)
senderr(EHOSTUNREACH); /* XXX */
if (!aarpresolve(ifp, m, (struct sockaddr_at *)dst, edst))
return (0);
/*
* In the phase 2 case, need to prepend an mbuf for the llc header.
*/
if ( aa->aa_flags & AFA_PHASE2 ) {
struct llc llc;
M_PREPEND(m, LLC_SNAPFRAMELEN, M_DONTWAIT);
if (m == NULL)
senderr(ENOBUFS);
llc.llc_dsap = llc.llc_ssap = LLC_SNAP_LSAP;
llc.llc_control = LLC_UI;
bcopy(at_org_code, llc.llc_snap_org_code, sizeof(at_org_code));
llc.llc_snap_ether_type = htons( ETHERTYPE_AT );
bcopy(&llc, mtod(m, caddr_t), LLC_SNAPFRAMELEN);
type = htons(m->m_pkthdr.len);
hlen = LLC_SNAPFRAMELEN + ETHER_HDR_LEN;
} else {
type = htons(ETHERTYPE_AT);
}
break;
}
#endif /* NETATALK */
case pseudo_AF_HDRCMPLT:
hdrcmplt = 1;
eh = (struct ether_header *)dst->sa_data;
(void)memcpy(esrc, eh->ether_shost, sizeof (esrc));
/* FALLTHROUGH */
case AF_UNSPEC:
loop_copy = 0; /* if this is for us, don't do it */
eh = (struct ether_header *)dst->sa_data;
(void)memcpy(edst, eh->ether_dhost, sizeof (edst));
type = eh->ether_type;
break;
default:
if_printf(ifp, "can't handle af%d\n", dst->sa_family);
senderr(EAFNOSUPPORT);
}
if (lle != NULL && (lle->la_flags & LLE_IFADDR)) {
int csum_flags = 0;
if (m->m_pkthdr.csum_flags & CSUM_IP)
csum_flags |= (CSUM_IP_CHECKED|CSUM_IP_VALID);
if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA)
csum_flags |= (CSUM_DATA_VALID|CSUM_PSEUDO_HDR);
if (m->m_pkthdr.csum_flags & CSUM_SCTP)
csum_flags |= CSUM_SCTP_VALID;
m->m_pkthdr.csum_flags |= csum_flags;
m->m_pkthdr.csum_data = 0xffff;
return (if_simloop(ifp, m, dst->sa_family, 0));
}
/*
* Add local net header. If no space in first mbuf,
* allocate another.
*/
M_PREPEND(m, ETHER_HDR_LEN, M_DONTWAIT);
if (m == NULL)
senderr(ENOBUFS);
eh = mtod(m, struct ether_header *);
(void)memcpy(&eh->ether_type, &type,
sizeof(eh->ether_type));
(void)memcpy(eh->ether_dhost, edst, sizeof (edst));
if (hdrcmplt)
(void)memcpy(eh->ether_shost, esrc,
sizeof(eh->ether_shost));
else
(void)memcpy(eh->ether_shost, IF_LLADDR(ifp),
sizeof(eh->ether_shost));
/*
* If a simplex interface, and the packet is being sent to our
* Ethernet address or a broadcast address, loopback a copy.
* XXX To make a simplex device behave exactly like a duplex
* device, we should copy in the case of sending to our own
* ethernet address (thus letting the original actually appear
* on the wire). However, we don't do that here for security
* reasons and compatibility with the original behavior.
*/
if ((ifp->if_flags & IFF_SIMPLEX) && loop_copy &&
((t = pf_find_mtag(m)) == NULL || !t->routed)) {
int csum_flags = 0;
if (m->m_pkthdr.csum_flags & CSUM_IP)
csum_flags |= (CSUM_IP_CHECKED|CSUM_IP_VALID);
if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA)
csum_flags |= (CSUM_DATA_VALID|CSUM_PSEUDO_HDR);
if (m->m_pkthdr.csum_flags & CSUM_SCTP)
csum_flags |= CSUM_SCTP_VALID;
if (m->m_flags & M_BCAST) {
struct mbuf *n;
/*
* Because if_simloop() modifies the packet, we need a
* writable copy through m_dup() instead of a readonly
* one as m_copy[m] would give us. The alternative would
* be to modify if_simloop() to handle the readonly mbuf,
* but performancewise it is mostly equivalent (trading
* extra data copying vs. extra locking).
*
* XXX This is a local workaround. A number of less
* often used kernel parts suffer from the same bug.
* See PR kern/105943 for a proposed general solution.
*/
if ((n = m_dup(m, M_DONTWAIT)) != NULL) {
n->m_pkthdr.csum_flags |= csum_flags;
if (csum_flags & CSUM_DATA_VALID)
n->m_pkthdr.csum_data = 0xffff;
(void)if_simloop(ifp, n, dst->sa_family, hlen);
} else
ifp->if_iqdrops++;
} else if (bcmp(eh->ether_dhost, eh->ether_shost,
ETHER_ADDR_LEN) == 0) {
m->m_pkthdr.csum_flags |= csum_flags;
if (csum_flags & CSUM_DATA_VALID)
m->m_pkthdr.csum_data = 0xffff;
(void) if_simloop(ifp, m, dst->sa_family, hlen);
return (0); /* XXX */
}
}
/*
* Bridges require special output handling.
*/
if (ifp->if_bridge) {
BRIDGE_OUTPUT(ifp, m, error);
return (error);
}
#ifdef DEV_CARP
if (ifp->if_carp &&
(error = carp_output(ifp, m, dst, NULL)))
goto bad;
#endif
/* Handle ng_ether(4) processing, if any */
if (IFP2AC(ifp)->ac_netgraph != NULL) {
KASSERT(ng_ether_output_p != NULL,
("ng_ether_output_p is NULL"));
if ((error = (*ng_ether_output_p)(ifp, &m)) != 0) {
bad: if (m != NULL)
m_freem(m);
return (error);
}
if (m == NULL)
return (0);
}
/* Continue with link-layer output */
return ether_output_frame(ifp, m);
}
/*
* Ethernet link layer output routine to send a raw frame to the device.
*
* This assumes that the 14 byte Ethernet header is present and contiguous
* in the first mbuf (if BRIDGE'ing).
*/
int
ether_output_frame(struct ifnet *ifp, struct mbuf *m)
{
#if defined(INET) || defined(INET6)
INIT_VNET_NET(ifp->if_vnet);
if (ip_fw_chk_ptr && V_ether_ipfw != 0) {
if (ether_ipfw_chk(&m, ifp, 0) == 0) {
if (m) {
m_freem(m);
return EACCES; /* pkt dropped */
} else
return 0; /* consumed e.g. in a pipe */
}
}
#endif
/*
* Queue message on interface, update output statistics if
* successful, and start output if interface not yet active.
*/
return ((ifp->if_transmit)(ifp, m));
}
#if defined(INET) || defined(INET6)
/*
* ipfw processing for ethernet packets (in and out).
* The second parameter is NULL from ether_demux, and ifp from
* ether_output_frame.
*/
int
ether_ipfw_chk(struct mbuf **m0, struct ifnet *dst, int shared)
{
INIT_VNET_INET(dst->if_vnet);
struct ether_header *eh;
struct ether_header save_eh;
struct mbuf *m;
int i;
struct ip_fw_args args;
struct dn_pkt_tag *dn_tag;
dn_tag = ip_dn_claim_tag(*m0);
if (dn_tag != NULL) {
if (dn_tag->rule != NULL && V_fw_one_pass)
/* dummynet packet, already partially processed */
return (1);
args.rule = dn_tag->rule; /* matching rule to restart */
args.rule_id = dn_tag->rule_id;
args.chain_id = dn_tag->chain_id;
} else
args.rule = NULL;
/*
* I need some amt of data to be contiguous, and in case others need
* the packet (shared==1) also better be in the first mbuf.
*/
m = *m0;
i = min( m->m_pkthdr.len, max_protohdr);
if ( shared || m->m_len < i) {
m = m_pullup(m, i);
if (m == NULL) {
*m0 = m;
return 0;
}
}
eh = mtod(m, struct ether_header *);
save_eh = *eh; /* save copy for restore below */
m_adj(m, ETHER_HDR_LEN); /* strip ethernet header */
args.m = m; /* the packet we are looking at */
args.oif = dst; /* destination, if any */
args.next_hop = NULL; /* we do not support forward yet */
args.eh = &save_eh; /* MAC header for bridged/MAC packets */
args.inp = NULL; /* used by ipfw uid/gid/jail rules */
i = ip_fw_chk_ptr(&args);
m = args.m;
if (m != NULL) {
/*
* Restore Ethernet header, as needed, in case the
* mbuf chain was replaced by ipfw.
*/
M_PREPEND(m, ETHER_HDR_LEN, M_DONTWAIT);
if (m == NULL) {
*m0 = m;
return 0;
}
if (eh != mtod(m, struct ether_header *))
bcopy(&save_eh, mtod(m, struct ether_header *),
ETHER_HDR_LEN);
}
*m0 = m;
if (i == IP_FW_DENY) /* drop */
return 0;
KASSERT(m != NULL, ("ether_ipfw_chk: m is NULL"));
if (i == IP_FW_PASS) /* a PASS rule. */
return 1;
if (ip_dn_io_ptr && (i == IP_FW_DUMMYNET)) {
/*
* Pass the pkt to dummynet, which consumes it.
* If shared, make a copy and keep the original.
*/
if (shared) {
m = m_copypacket(m, M_DONTWAIT);
if (m == NULL)
return 0;
} else {
/*
* Pass the original to dummynet and
* nothing back to the caller
*/
*m0 = NULL ;
}
ip_dn_io_ptr(&m, dst ? DN_TO_ETH_OUT: DN_TO_ETH_DEMUX, &args);
return 0;
}
/*
* XXX at some point add support for divert/forward actions.
* If none of the above matches, we have to drop the pkt.
*/
return 0;
}
#endif
/*
* Process a received Ethernet packet; the packet is in the
* mbuf chain m with the ethernet header at the front.
*/
static void
ether_input(struct ifnet *ifp, struct mbuf *m)
{
struct ether_header *eh;
u_short etype;
if ((ifp->if_flags & IFF_UP) == 0) {
m_freem(m);
return;
}
#ifdef DIAGNOSTIC
if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) {
if_printf(ifp, "discard frame at !IFF_DRV_RUNNING\n");
m_freem(m);
return;
}
#endif
/*
* Do consistency checks to verify assumptions
* made by code past this point.
*/
if ((m->m_flags & M_PKTHDR) == 0) {
if_printf(ifp, "discard frame w/o packet header\n");
ifp->if_ierrors++;
m_freem(m);
return;
}
if (m->m_len < ETHER_HDR_LEN) {
/* XXX maybe should pullup? */
if_printf(ifp, "discard frame w/o leading ethernet "
"header (len %u pkt len %u)\n",
m->m_len, m->m_pkthdr.len);
ifp->if_ierrors++;
m_freem(m);
return;
}
eh = mtod(m, struct ether_header *);
etype = ntohs(eh->ether_type);
if (m->m_pkthdr.rcvif == NULL) {
if_printf(ifp, "discard frame w/o interface pointer\n");
ifp->if_ierrors++;
m_freem(m);
return;
}
#ifdef DIAGNOSTIC
if (m->m_pkthdr.rcvif != ifp) {
if_printf(ifp, "Warning, frame marked as received on %s\n",
m->m_pkthdr.rcvif->if_xname);
}
#endif
CURVNET_SET_QUIET(ifp->if_vnet);
if (ETHER_IS_MULTICAST(eh->ether_dhost)) {
if (ETHER_IS_BROADCAST(eh->ether_dhost))
m->m_flags |= M_BCAST;
else
m->m_flags |= M_MCAST;
ifp->if_imcasts++;
}
#ifdef MAC
/*
* Tag the mbuf with an appropriate MAC label before any other
* consumers can get to it.
*/
mac_ifnet_create_mbuf(ifp, m);
#endif
/*
* Give bpf a chance at the packet.
*/
ETHER_BPF_MTAP(ifp, m);
/*
* If the CRC is still on the packet, trim it off. We do this once
* and once only in case we are re-entered. Nothing else on the
* Ethernet receive path expects to see the FCS.
*/
if (m->m_flags & M_HASFCS) {
m_adj(m, -ETHER_CRC_LEN);
m->m_flags &= ~M_HASFCS;
}
ifp->if_ibytes += m->m_pkthdr.len;
/* Allow monitor mode to claim this frame, after stats are updated. */
if (ifp->if_flags & IFF_MONITOR) {
m_freem(m);
CURVNET_RESTORE();
return;
}
/* Handle input from a lagg(4) port */
if (ifp->if_type == IFT_IEEE8023ADLAG) {
KASSERT(lagg_input_p != NULL,
("%s: if_lagg not loaded!", __func__));
m = (*lagg_input_p)(ifp, m);
if (m != NULL)
ifp = m->m_pkthdr.rcvif;
else
return;
}
/*
* If the hardware did not process an 802.1Q tag, do this now,
* to allow 802.1P priority frames to be passed to the main input
* path correctly.
* TODO: Deal with Q-in-Q frames, but not arbitrary nesting levels.
*/
if ((m->m_flags & M_VLANTAG) == 0 && etype == ETHERTYPE_VLAN) {
struct ether_vlan_header *evl;
if (m->m_len < sizeof(*evl) &&
(m = m_pullup(m, sizeof(*evl))) == NULL) {
#ifdef DIAGNOSTIC
if_printf(ifp, "cannot pullup VLAN header\n");
#endif
ifp->if_ierrors++;
m_freem(m);
return;
}
evl = mtod(m, struct ether_vlan_header *);
m->m_pkthdr.ether_vtag = ntohs(evl->evl_tag);
m->m_flags |= M_VLANTAG;
bcopy((char *)evl, (char *)evl + ETHER_VLAN_ENCAP_LEN,
ETHER_HDR_LEN - ETHER_TYPE_LEN);
m_adj(m, ETHER_VLAN_ENCAP_LEN);
}
/* Allow ng_ether(4) to claim this frame. */
if (IFP2AC(ifp)->ac_netgraph != NULL) {
KASSERT(ng_ether_input_p != NULL,
("%s: ng_ether_input_p is NULL", __func__));
m->m_flags &= ~M_PROMISC;
(*ng_ether_input_p)(ifp, &m);
if (m == NULL) {
CURVNET_RESTORE();
return;
}
}
/*
* Allow if_bridge(4) to claim this frame.
* The BRIDGE_INPUT() macro will update ifp if the bridge changed it
* and the frame should be delivered locally.
*/
if (ifp->if_bridge != NULL) {
m->m_flags &= ~M_PROMISC;
BRIDGE_INPUT(ifp, m);
if (m == NULL) {
CURVNET_RESTORE();
return;
}
}
#ifdef DEV_CARP
/*
* Clear M_PROMISC on frame so that carp(4) will see it when the
* mbuf flows up to Layer 3.
* FreeBSD's implementation of carp(4) uses the inprotosw
* to dispatch IPPROTO_CARP. carp(4) also allocates its own
* Ethernet addresses of the form 00:00:5e:00:01:xx, which
* is outside the scope of the M_PROMISC test below.
* TODO: Maintain a hash table of ethernet addresses other than
* ether_dhost which may be active on this ifp.
*/
if (ifp->if_carp && carp_forus(ifp->if_carp, eh->ether_dhost)) {
m->m_flags &= ~M_PROMISC;
} else
#endif
{
/*
* If the frame received was not for our MAC address, set the
* M_PROMISC flag on the mbuf chain. The frame may need to
* be seen by the rest of the Ethernet input path in case of
* re-entry (e.g. bridge, vlan, netgraph) but should not be
* seen by upper protocol layers.
*/
if (!ETHER_IS_MULTICAST(eh->ether_dhost) &&
bcmp(IF_LLADDR(ifp), eh->ether_dhost, ETHER_ADDR_LEN) != 0)
m->m_flags |= M_PROMISC;
}
/* First chunk of an mbuf contains good entropy */
if (harvest.ethernet)
random_harvest(m, 16, 3, 0, RANDOM_NET);
ether_demux(ifp, m);
CURVNET_RESTORE();
}
/*
* Upper layer processing for a received Ethernet packet.
*/
void
ether_demux(struct ifnet *ifp, struct mbuf *m)
{
struct ether_header *eh;
int isr;
u_short ether_type;
#if defined(NETATALK)
struct llc *l;
#endif
KASSERT(ifp != NULL, ("%s: NULL interface pointer", __func__));
#if defined(INET) || defined(INET6)
INIT_VNET_NET(ifp->if_vnet);
/*
* Allow dummynet and/or ipfw to claim the frame.
* Do not do this for PROMISC frames in case we are re-entered.
*/
if (ip_fw_chk_ptr && V_ether_ipfw != 0 && !(m->m_flags & M_PROMISC)) {
if (ether_ipfw_chk(&m, NULL, 0) == 0) {
if (m)
m_freem(m); /* dropped; free mbuf chain */
return; /* consumed */
}
}
#endif
eh = mtod(m, struct ether_header *);
ether_type = ntohs(eh->ether_type);
/*
* If this frame has a VLAN tag other than 0, call vlan_input()
* if its module is loaded. Otherwise, drop.
*/
if ((m->m_flags & M_VLANTAG) &&
EVL_VLANOFTAG(m->m_pkthdr.ether_vtag) != 0) {
if (ifp->if_vlantrunk == NULL) {
ifp->if_noproto++;
m_freem(m);
return;
}
KASSERT(vlan_input_p != NULL,("%s: VLAN not loaded!",
__func__));
/* Clear before possibly re-entering ether_input(). */
m->m_flags &= ~M_PROMISC;
(*vlan_input_p)(ifp, m);
return;
}
/*
* Pass promiscuously received frames to the upper layer if the user
* requested this by setting IFF_PPROMISC. Otherwise, drop them.
*/
if ((ifp->if_flags & IFF_PPROMISC) == 0 && (m->m_flags & M_PROMISC)) {
m_freem(m);
return;
}
/*
* Reset layer specific mbuf flags to avoid confusing upper layers.
* Strip off Ethernet header.
*/
m->m_flags &= ~M_VLANTAG;
m->m_flags &= ~(M_PROTOFLAGS);
m_adj(m, ETHER_HDR_LEN);
/*
* Dispatch frame to upper layer.
*/
switch (ether_type) {
#ifdef INET
case ETHERTYPE_IP:
if ((m = ip_fastforward(m)) == NULL)
return;
isr = NETISR_IP;
break;
case ETHERTYPE_ARP:
if (ifp->if_flags & IFF_NOARP) {
/* Discard packet if ARP is disabled on interface */
m_freem(m);
return;
}
isr = NETISR_ARP;
break;
#endif
#ifdef IPX
case ETHERTYPE_IPX:
if (ef_inputp && ef_inputp(ifp, eh, m) == 0)
return;
isr = NETISR_IPX;
break;
#endif
#ifdef INET6
case ETHERTYPE_IPV6:
isr = NETISR_IPV6;
break;
#endif
#ifdef NETATALK
case ETHERTYPE_AT:
isr = NETISR_ATALK1;
break;
case ETHERTYPE_AARP:
isr = NETISR_AARP;
break;
#endif /* NETATALK */
default:
#ifdef IPX
if (ef_inputp && ef_inputp(ifp, eh, m) == 0)
return;
#endif /* IPX */
#if defined(NETATALK)
if (ether_type > ETHERMTU)
goto discard;
l = mtod(m, struct llc *);
if (l->llc_dsap == LLC_SNAP_LSAP &&
l->llc_ssap == LLC_SNAP_LSAP &&
l->llc_control == LLC_UI) {
if (bcmp(&(l->llc_snap_org_code)[0], at_org_code,
sizeof(at_org_code)) == 0 &&
ntohs(l->llc_snap_ether_type) == ETHERTYPE_AT) {
m_adj(m, LLC_SNAPFRAMELEN);
isr = NETISR_ATALK2;
break;
}
if (bcmp(&(l->llc_snap_org_code)[0], aarp_org_code,
sizeof(aarp_org_code)) == 0 &&
ntohs(l->llc_snap_ether_type) == ETHERTYPE_AARP) {
m_adj(m, LLC_SNAPFRAMELEN);
isr = NETISR_AARP;
break;
}
}
#endif /* NETATALK */
goto discard;
}
netisr_dispatch(isr, m);
return;
discard:
/*
* Packet is to be discarded. If netgraph is present,
* hand the packet to it for last chance processing;
* otherwise dispose of it.
*/
if (IFP2AC(ifp)->ac_netgraph != NULL) {
KASSERT(ng_ether_input_orphan_p != NULL,
("ng_ether_input_orphan_p is NULL"));
/*
* Put back the ethernet header so netgraph has a
* consistent view of inbound packets.
*/
M_PREPEND(m, ETHER_HDR_LEN, M_DONTWAIT);
(*ng_ether_input_orphan_p)(ifp, m);
return;
}
m_freem(m);
}
/*
* Convert Ethernet address to printable (loggable) representation.
* This routine is for compatibility; it's better to just use
*
* printf("%6D", <pointer to address>, ":");
*
* since there's no static buffer involved.
*/
char *
ether_sprintf(const u_char *ap)
{
static char etherbuf[18];
snprintf(etherbuf, sizeof (etherbuf), "%6D", ap, ":");
return (etherbuf);
}
/*
* Perform common duties while attaching to interface list
*/
void
ether_ifattach(struct ifnet *ifp, const u_int8_t *lla)
{
int i;
struct ifaddr *ifa;
struct sockaddr_dl *sdl;
ifp->if_addrlen = ETHER_ADDR_LEN;
ifp->if_hdrlen = ETHER_HDR_LEN;
if_attach(ifp);
ifp->if_mtu = ETHERMTU;
ifp->if_output = ether_output;
ifp->if_input = ether_input;
ifp->if_resolvemulti = ether_resolvemulti;
if (ifp->if_baudrate == 0)
ifp->if_baudrate = IF_Mbps(10); /* just a default */
ifp->if_broadcastaddr = etherbroadcastaddr;
ifa = ifp->if_addr;
KASSERT(ifa != NULL, ("%s: no lladdr!\n", __func__));
sdl = (struct sockaddr_dl *)ifa->ifa_addr;
sdl->sdl_type = IFT_ETHER;
sdl->sdl_alen = ifp->if_addrlen;
bcopy(lla, LLADDR(sdl), ifp->if_addrlen);
bpfattach(ifp, DLT_EN10MB, ETHER_HDR_LEN);
if (ng_ether_attach_p != NULL)
(*ng_ether_attach_p)(ifp);
/* Announce Ethernet MAC address if non-zero. */
for (i = 0; i < ifp->if_addrlen; i++)
if (lla[i] != 0)
break;
if (i != ifp->if_addrlen)
if_printf(ifp, "Ethernet address: %6D\n", lla, ":");
}
/*
* Perform common duties while detaching an Ethernet interface
*/
void
ether_ifdetach(struct ifnet *ifp)
{
if (IFP2AC(ifp)->ac_netgraph != NULL) {
KASSERT(ng_ether_detach_p != NULL,
("ng_ether_detach_p is NULL"));
(*ng_ether_detach_p)(ifp);
}
bpfdetach(ifp);
if_detach(ifp);
}
SYSCTL_DECL(_net_link);
SYSCTL_NODE(_net_link, IFT_ETHER, ether, CTLFLAG_RW, 0, "Ethernet");
#if defined(INET) || defined(INET6)
SYSCTL_V_INT(V_NET, vnet_net, _net_link_ether, OID_AUTO, ipfw, CTLFLAG_RW,
ether_ipfw, 0, "Pass ether pkts through firewall");
#endif
#if 0
/*
* This is for reference. We have a table-driven version
* of the little-endian crc32 generator, which is faster
* than the double-loop.
*/
uint32_t
ether_crc32_le(const uint8_t *buf, size_t len)
{
size_t i;
uint32_t crc;
int bit;
uint8_t data;
crc = 0xffffffff; /* initial value */
for (i = 0; i < len; i++) {
for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) {
carry = (crc ^ data) & 1;
crc >>= 1;
if (carry)
crc = (crc ^ ETHER_CRC_POLY_LE);
}
}
return (crc);
}
#else
uint32_t
ether_crc32_le(const uint8_t *buf, size_t len)
{
static const uint32_t crctab[] = {
0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac,
0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c,
0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c,
0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c
};
size_t i;
uint32_t crc;
crc = 0xffffffff; /* initial value */
for (i = 0; i < len; i++) {
crc ^= buf[i];
crc = (crc >> 4) ^ crctab[crc & 0xf];
crc = (crc >> 4) ^ crctab[crc & 0xf];
}
return (crc);
}
#endif
uint32_t
ether_crc32_be(const uint8_t *buf, size_t len)
{
size_t i;
uint32_t crc, carry;
int bit;
uint8_t data;
crc = 0xffffffff; /* initial value */
for (i = 0; i < len; i++) {
for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) {
carry = ((crc & 0x80000000) ? 1 : 0) ^ (data & 0x01);
crc <<= 1;
if (carry)
crc = (crc ^ ETHER_CRC_POLY_BE) | carry;
}
}
return (crc);
}
int
ether_ioctl(struct ifnet *ifp, u_long command, caddr_t data)
{
struct ifaddr *ifa = (struct ifaddr *) data;
struct ifreq *ifr = (struct ifreq *) data;
int error = 0;
switch (command) {
case SIOCSIFADDR:
ifp->if_flags |= IFF_UP;
switch (ifa->ifa_addr->sa_family) {
#ifdef INET
case AF_INET:
ifp->if_init(ifp->if_softc); /* before arpwhohas */
arp_ifinit(ifp, ifa);
break;
#endif
#ifdef IPX
/*
* XXX - This code is probably wrong
*/
case AF_IPX:
{
struct ipx_addr *ina = &(IA_SIPX(ifa)->sipx_addr);
if (ipx_nullhost(*ina))
ina->x_host =
*(union ipx_host *)
IF_LLADDR(ifp);
else {
bcopy((caddr_t) ina->x_host.c_host,
(caddr_t) IF_LLADDR(ifp),
ETHER_ADDR_LEN);
}
/*
* Set new address
*/
ifp->if_init(ifp->if_softc);
break;
}
#endif
default:
ifp->if_init(ifp->if_softc);
break;
}
break;
case SIOCGIFADDR:
{
struct sockaddr *sa;
sa = (struct sockaddr *) & ifr->ifr_data;
bcopy(IF_LLADDR(ifp),
(caddr_t) sa->sa_data, ETHER_ADDR_LEN);
}
break;
case SIOCSIFMTU:
/*
* Set the interface MTU.
*/
if (ifr->ifr_mtu > ETHERMTU) {
error = EINVAL;
} else {
ifp->if_mtu = ifr->ifr_mtu;
}
break;
default:
error = EINVAL; /* XXX netbsd has ENOTTY??? */
break;
}
return (error);
}
static int
ether_resolvemulti(struct ifnet *ifp, struct sockaddr **llsa,
struct sockaddr *sa)
{
struct sockaddr_dl *sdl;
#ifdef INET
struct sockaddr_in *sin;
#endif
#ifdef INET6
struct sockaddr_in6 *sin6;
#endif
u_char *e_addr;
switch(sa->sa_family) {
case AF_LINK:
/*
* No mapping needed. Just check that it's a valid MC address.
*/
sdl = (struct sockaddr_dl *)sa;
e_addr = LLADDR(sdl);
if (!ETHER_IS_MULTICAST(e_addr))
return EADDRNOTAVAIL;
*llsa = 0;
return 0;
#ifdef INET
case AF_INET:
sin = (struct sockaddr_in *)sa;
if (!IN_MULTICAST(ntohl(sin->sin_addr.s_addr)))
return EADDRNOTAVAIL;
sdl = malloc(sizeof *sdl, M_IFMADDR,
M_NOWAIT|M_ZERO);
if (sdl == NULL)
return ENOMEM;
sdl->sdl_len = sizeof *sdl;
sdl->sdl_family = AF_LINK;
sdl->sdl_index = ifp->if_index;
sdl->sdl_type = IFT_ETHER;
sdl->sdl_alen = ETHER_ADDR_LEN;
e_addr = LLADDR(sdl);
ETHER_MAP_IP_MULTICAST(&sin->sin_addr, e_addr);
*llsa = (struct sockaddr *)sdl;
return 0;
#endif
#ifdef INET6
case AF_INET6:
sin6 = (struct sockaddr_in6 *)sa;
if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) {
/*
* An IP6 address of 0 means listen to all
* of the Ethernet multicast address used for IP6.
* (This is used for multicast routers.)
*/
ifp->if_flags |= IFF_ALLMULTI;
*llsa = 0;
return 0;
}
if (!IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr))
return EADDRNOTAVAIL;
sdl = malloc(sizeof *sdl, M_IFMADDR,
M_NOWAIT|M_ZERO);
if (sdl == NULL)
return (ENOMEM);
sdl->sdl_len = sizeof *sdl;
sdl->sdl_family = AF_LINK;
sdl->sdl_index = ifp->if_index;
sdl->sdl_type = IFT_ETHER;
sdl->sdl_alen = ETHER_ADDR_LEN;
e_addr = LLADDR(sdl);
ETHER_MAP_IPV6_MULTICAST(&sin6->sin6_addr, e_addr);
*llsa = (struct sockaddr *)sdl;
return 0;
#endif
default:
/*
* Well, the text isn't quite right, but it's the name
* that counts...
*/
return EAFNOSUPPORT;
}
}
static void*
ether_alloc(u_char type, struct ifnet *ifp)
{
struct arpcom *ac;
ac = malloc(sizeof(struct arpcom), M_ARPCOM, M_WAITOK | M_ZERO);
ac->ac_ifp = ifp;
return (ac);
}
static void
ether_free(void *com, u_char type)
{
free(com, M_ARPCOM);
}
static int
ether_modevent(module_t mod, int type, void *data)
{
switch (type) {
case MOD_LOAD:
if_register_com_alloc(IFT_ETHER, ether_alloc, ether_free);
break;
case MOD_UNLOAD:
if_deregister_com_alloc(IFT_ETHER);
break;
default:
return EOPNOTSUPP;
}
return (0);
}
static moduledata_t ether_mod = {
"ether",
ether_modevent,
0
};
void
ether_vlan_mtap(struct bpf_if *bp, struct mbuf *m, void *data, u_int dlen)
{
struct ether_vlan_header vlan;
struct mbuf mv, mb;
KASSERT((m->m_flags & M_VLANTAG) != 0,
("%s: vlan information not present", __func__));
KASSERT(m->m_len >= sizeof(struct ether_header),
("%s: mbuf not large enough for header", __func__));
bcopy(mtod(m, char *), &vlan, sizeof(struct ether_header));
vlan.evl_proto = vlan.evl_encap_proto;
vlan.evl_encap_proto = htons(ETHERTYPE_VLAN);
vlan.evl_tag = htons(m->m_pkthdr.ether_vtag);
m->m_len -= sizeof(struct ether_header);
m->m_data += sizeof(struct ether_header);
/*
* If a data link has been supplied by the caller, then we will need to
* re-create a stack allocated mbuf chain with the following structure:
*
* (1) mbuf #1 will contain the supplied data link
* (2) mbuf #2 will contain the vlan header
* (3) mbuf #3 will contain the original mbuf's packet data
*
* Otherwise, submit the packet and vlan header via bpf_mtap2().
*/
if (data != NULL) {
mv.m_next = m;
mv.m_data = (caddr_t)&vlan;
mv.m_len = sizeof(vlan);
mb.m_next = &mv;
mb.m_data = data;
mb.m_len = dlen;
bpf_mtap(bp, &mb);
} else
bpf_mtap2(bp, &vlan, sizeof(vlan), m);
m->m_len += sizeof(struct ether_header);
m->m_data -= sizeof(struct ether_header);
}
struct mbuf *
ether_vlanencap(struct mbuf *m, uint16_t tag)
{
struct ether_vlan_header *evl;
M_PREPEND(m, ETHER_VLAN_ENCAP_LEN, M_DONTWAIT);
if (m == NULL)
return (NULL);
/* M_PREPEND takes care of m_len, m_pkthdr.len for us */
if (m->m_len < sizeof(*evl)) {
m = m_pullup(m, sizeof(*evl));
if (m == NULL)
return (NULL);
}
/*
* Transform the Ethernet header into an Ethernet header
* with 802.1Q encapsulation.
*/
evl = mtod(m, struct ether_vlan_header *);
bcopy((char *)evl + ETHER_VLAN_ENCAP_LEN,
(char *)evl, ETHER_HDR_LEN - ETHER_TYPE_LEN);
evl->evl_encap_proto = htons(ETHERTYPE_VLAN);
evl->evl_tag = htons(tag);
return (m);
}
DECLARE_MODULE(ether, ether_mod, SI_SUB_INIT_IF, SI_ORDER_ANY);
MODULE_VERSION(ether, 1);
Reference in New Issue View Git Blame Copy Permalink