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freebsd-skq/sys/net/if_ethersubr.c
Oleg Bulyzhin 897c0f57d4 1) dummynet_io() declaration has changed. 
2) Alter packet flow inside dummynet: allow certain packets to bypass
dummynet scheduler. Benefits are:

- lower latency: if packet flow does not exceed pipe bandwidth, packets
  will not be (up to tick) delayed (due to dummynet's scheduler granularity).
- lower overhead: if packet avoids dummynet scheduler it shouldn't reenter ip
  stack later. Such packets can be fastforwarded.
- recursion (which can lead to kernel stack exhaution) eliminated. This fix
  long existed panic, which can be triggered this way:
  	kldload dummynet
	sysctl net.inet.ip.fw.one_pass=0
	ipfw pipe 1 config bw 0
	for i in `jot 30`; do ipfw add 1 pipe 1 icmp from any to any; done
	ping -c 1 localhost

3) Three new sysctl nodes are added:
net.inet.ip.dummynet.io_pkt -		packets passed to dummynet
net.inet.ip.dummynet.io_pkt_fast - 	packets avoided dummynet scheduler
net.inet.ip.dummynet.io_pkt_drop -	packets dropped by dummynet

P.S. Above comments are true only for layer 3 packets. Layer 2 packet flow
     is not changed yet.

MFC after:	3 month
2007-11-06 23:01:42 +00:00

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/*-
* 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>
#include <net/pf_mtag.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 *);
/* 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,
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;
struct pf_mtag *t;
int loop_copy = 1;
int hlen; /* link layer header length */
#ifdef MAC
error = mac_ifnet_check_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 &&
((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_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;
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
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);
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)
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)
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);
}
/*
* 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)
/*
* Allow dummynet and/or ipfw to claim the frame.
* Do not do this for PROMISC frames in case we are re-entered.
*/
if (IPFW_LOADED && ether_ipfw != 0 && !(m->m_flags & M_PROMISC)) {
struct ip_fw *rule = ip_dn_claim_rule(m);
if (ether_ipfw_chk(&m, NULL, &rule, 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, ":");
if (ifp->if_flags & IFF_NEEDSGIANT)
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, 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;
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);
}
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);
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