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freebsd/sys/net/if_ethersubr.c
Christian S.J. Peron d05d46160a Use ETHER_BPF_MTAP() instead of BPF_MTAP() here. It's possible
incoming packets have had their 802.1Q tags processed by the
hardware, resulting in them being stripped from the packets, and
placed on the mbuf.  This fixes the processing of 802.1Q tags when
hardware offload of 802.1Q tags is enabled.
2007-02-22 14:50:31 +00:00

1243 lines
30 KiB
C

/*-
* 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_mac.h"
#include "opt_netgraph.h"
#include "opt_carp.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/module.h>
#include <sys/mbuf.h>
#include <sys/random.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <sys/sysctl.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>
#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>
#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>
/* 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 *);
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 senderr(e) do { error = (e); goto bad;} while (0)
#if defined(INET) || defined(INET6)
int
ether_ipfw_chk(struct mbuf **m0, struct ifnet *dst,
struct ip_fw **rule, int shared);
static int ether_ipfw;
#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 rtentry *rt0)
{
short type;
int error, hdrcmplt = 0;
u_char esrc[ETHER_ADDR_LEN], edst[ETHER_ADDR_LEN];
struct ether_header *eh;
int loop_copy = 1;
int hlen; /* link layer header length */
#ifdef MAC
error = mac_check_ifnet_transmit(ifp, m);
if (error)
senderr(error);
#endif
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:
error = arpresolve(ifp, rt0, m, dst, edst);
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:
error = nd6_storelladdr(ifp, rt0, m, dst, (u_char *)edst);
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);
}
/*
* 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 &&
m_tag_find(m, PACKET_TAG_PF_ROUTED, NULL) == NULL) {
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_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)
{
int error;
#if defined(INET) || defined(INET6)
struct ip_fw *rule = ip_dn_claim_rule(m);
if (IPFW_LOADED && ether_ipfw != 0) {
if (ether_ipfw_chk(&m, ifp, &rule, 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.
*/
IFQ_HANDOFF(ifp, m, error);
return (error);
}
#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,
struct ip_fw **rule, int shared)
{
struct ether_header *eh;
struct ether_header save_eh;
struct mbuf *m;
int i;
struct ip_fw_args args;
if (*rule != NULL && fw_one_pass)
return 1; /* dummynet packet, already partially processed */
/*
* 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.rule = *rule; /* matching rule to restart */
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;
*rule = args.rule;
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 (DUMMYNET_LOADED && (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;
/*
* 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.len >
ETHER_MAX_FRAME(ifp, etype, m->m_flags & M_HASFCS)) {
if_printf(ifp, "discard oversize frame "
"(ether type %x flags %x len %u > max %lu)\n",
etype, m->m_flags, m->m_pkthdr.len,
ETHER_MAX_FRAME(ifp, etype,
m->m_flags & M_HASFCS));
ifp->if_ierrors++;
m_freem(m);
return;
}
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
#ifdef MAC
/*
* Tag the mbuf with an appropriate MAC label before any other
* consumers can get to it.
*/
mac_create_mbuf_from_ifnet(ifp, m);
#endif
/*
* Give bpf a chance at the packet. Process any 802.1Q tags
* that may have been attached to the mbuf.
*/
ETHER_BPF_MTAP(ifp, m);
/* If the CRC is still on the packet, trim it off. */
if (m->m_flags & M_HASFCS) {
m_adj(m, -ETHER_CRC_LEN);
m->m_flags &= ~M_HASFCS;
}
ifp->if_ibytes += m->m_pkthdr.len;
if (ifp->if_flags & IFF_MONITOR) {
/*
* Interface marked for monitoring; discard packet.
*/
m_freem(m);
return;
}
/* Handle ng_ether(4) processing, if any */
if (IFP2AC(ifp)->ac_netgraph != NULL) {
KASSERT(ng_ether_input_p != NULL,
("ng_ether_input_p is NULL"));
(*ng_ether_input_p)(ifp, &m);
if (m == NULL)
return;
}
/*
* Tap the packet off here for a bridge. bridge_input()
* will return NULL if it has consumed the packet, otherwise
* it gets processed as normal. Note that bridge_input()
* will always return the original packet if we need to
* process it locally.
*
* XXX: When changing the below block, please also look
* at the src/sys/netgraph/ng_ether.c:ng_ether_rcv_upper()
*/
if (ifp->if_bridge) {
BRIDGE_INPUT(ifp, m);
if (m == NULL)
return;
}
/* First chunk of an mbuf contains good entropy */
if (harvest.ethernet)
random_harvest(m, 16, 3, 0, RANDOM_NET);
ether_demux(ifp, m);
}
/*
* 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
#if defined(INET) || defined(INET6)
struct ip_fw *rule = ip_dn_claim_rule(m);
#endif
KASSERT(ifp != NULL, ("ether_demux: NULL interface pointer"));
eh = mtod(m, struct ether_header *);
ether_type = ntohs(eh->ether_type);
#if defined(INET) || defined(INET6)
if (rule) /* packet was already bridged */
goto post_stats;
#endif
if (!(ifp->if_bridge) &&
!((ether_type == ETHERTYPE_VLAN || m->m_flags & M_VLANTAG) &&
ifp->if_vlantrunk != NULL)) {
#ifdef DEV_CARP
/*
* XXX: Okay, we need to call carp_forus() and - if it is for
* us jump over code that does the normal check
* "IF_LLADDR(ifp) == ether_dhost". The check sequence is a bit
* different from OpenBSD, so we jump over as few code as
* possible, to catch _all_ sanity checks. This needs
* evaluation, to see if the carp ether_dhost values break any
* of these checks!
*/
if (ifp->if_carp && carp_forus(ifp->if_carp, eh->ether_dhost))
goto pre_stats;
#endif
/*
* Discard packet if upper layers shouldn't see it because it
* was unicast to a different Ethernet address. If the driver
* is working properly, then this situation can only happen
* when the interface is in promiscuous mode.
*
* If VLANs are active, and this packet has a VLAN tag, do
* not drop it here but pass it on to the VLAN layer, to
* give them a chance to consider it as well (e. g. in case
* bridging is only active on a VLAN). They will drop it if
* it's undesired.
*/
if ((ifp->if_flags & IFF_PROMISC) != 0
&& !ETHER_IS_MULTICAST(eh->ether_dhost)
&& bcmp(eh->ether_dhost,
IF_LLADDR(ifp), ETHER_ADDR_LEN) != 0
&& (ifp->if_flags & IFF_PPROMISC) == 0) {
m_freem(m);
return;
}
}
#ifdef DEV_CARP
pre_stats:
#endif
/* Discard packet if interface is not up */
if ((ifp->if_flags & IFF_UP) == 0) {
m_freem(m);
return;
}
if (ETHER_IS_MULTICAST(eh->ether_dhost)) {
if (bcmp(etherbroadcastaddr, eh->ether_dhost,
sizeof(etherbroadcastaddr)) == 0)
m->m_flags |= M_BCAST;
else
m->m_flags |= M_MCAST;
}
if (m->m_flags & (M_BCAST|M_MCAST))
ifp->if_imcasts++;
#if defined(INET) || defined(INET6)
post_stats:
if (IPFW_LOADED && ether_ipfw != 0) {
if (ether_ipfw_chk(&m, NULL, &rule, 0) == 0) {
if (m)
m_freem(m);
return;
}
}
#endif
/*
* Check to see if the device performed the VLAN decapsulation and
* provided us with the tag.
*/
if (m->m_flags & M_VLANTAG) {
/*
* If no VLANs are configured, drop.
*/
if (ifp->if_vlantrunk == NULL) {
ifp->if_noproto++;
m_freem(m);
return;
}
/*
* vlan_input() will either recursively call ether_input()
* or drop the packet.
*/
KASSERT(vlan_input_p != NULL,("ether_input: VLAN not loaded!"));
(*vlan_input_p)(ifp, m);
return;
}
/*
* Handle protocols that expect to have the Ethernet header
* (and possibly FCS) intact.
*/
switch (ether_type) {
case ETHERTYPE_VLAN:
if (ifp->if_vlantrunk != NULL) {
KASSERT(vlan_input_p,("ether_input: VLAN not loaded!"));
(*vlan_input_p)(ifp, m);
} else {
ifp->if_noproto++;
m_freem(m);
}
return;
}
/* Strip off Ethernet header. */
m_adj(m, ETHER_HDR_LEN);
/* If the CRC is still on the packet, trim it off. */
if (m->m_flags & M_HASFCS) {
m_adj(m, -ETHER_CRC_LEN);
m->m_flags &= ~M_HASFCS;
}
/* Reset layer specific mbuf flags to avoid confusing upper layers. */
m->m_flags &= ~(M_PROTOFLAGS);
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, ":");
if (debug_mpsafenet && (ifp->if_flags & IFF_NEEDSGIANT) != 0)
if_printf(ifp, "if_start running deferred for Giant\n");
}
/*
* 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_INT(_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, int 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;
MALLOC(sdl, struct sockaddr_dl *, 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;
MALLOC(sdl, struct sockaddr_dl *, 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);
}
DECLARE_MODULE(ether, ether_mod, SI_SUB_INIT_IF, SI_ORDER_ANY);
MODULE_VERSION(ether, 1);