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freebsd-nq/sys/net/if_ethersubr.c
Gleb Smirnoff 5b64c645d7 Stop entering the network epoch in ether_input(), unless driver 
is marked with IFF_NEEDSEPOCH.
2020-01-23 01:47:43 +00:00

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/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* 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.
* 3. 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_inet.h"
#include "opt_inet6.h"
#include "opt_netgraph.h"
#include "opt_mbuf_profiling.h"
#include "opt_rss.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/eventhandler.h>
#include <sys/jail.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/module.h>
#include <sys/mbuf.h>
#include <sys/proc.h>
#include <sys/priv.h>
#include <sys/random.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <sys/sysctl.h>
#include <sys/uuid.h>
#include <net/ieee_oui.h>
#include <net/if.h>
#include <net/if_var.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/pfil.h>
#include <net/rss_config.h>
#include <net/vnet.h>
#include <netpfil/pf/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_carp.h>
#include <netinet/ip_var.h>
#endif
#ifdef INET6
#include <netinet6/nd6.h>
#endif
#include <security/mac/mac_framework.h>
#include <crypto/sha1.h>
#ifdef CTASSERT
CTASSERT(sizeof (struct ether_header) == ETHER_ADDR_LEN * 2 + 2);
CTASSERT(sizeof (struct ether_addr) == ETHER_ADDR_LEN);
#endif
VNET_DEFINE(pfil_head_t, link_pfil_head); /* Packet filter hooks */
/* 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 */
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 *);
#ifdef VIMAGE
static void ether_reassign(struct ifnet *, struct vnet *, char *);
#endif
static int ether_requestencap(struct ifnet *, struct if_encap_req *);
#define senderr(e) do { error = (e); goto bad;} while (0)
static void
update_mbuf_csumflags(struct mbuf *src, struct mbuf *dst)
{
int csum_flags = 0;
if (src->m_pkthdr.csum_flags & CSUM_IP)
csum_flags |= (CSUM_IP_CHECKED|CSUM_IP_VALID);
if (src->m_pkthdr.csum_flags & CSUM_DELAY_DATA)
csum_flags |= (CSUM_DATA_VALID|CSUM_PSEUDO_HDR);
if (src->m_pkthdr.csum_flags & CSUM_SCTP)
csum_flags |= CSUM_SCTP_VALID;
dst->m_pkthdr.csum_flags |= csum_flags;
if (csum_flags & CSUM_DATA_VALID)
dst->m_pkthdr.csum_data = 0xffff;
}
/*
* Handle link-layer encapsulation requests.
*/
static int
ether_requestencap(struct ifnet *ifp, struct if_encap_req *req)
{
struct ether_header *eh;
struct arphdr *ah;
uint16_t etype;
const u_char *lladdr;
if (req->rtype != IFENCAP_LL)
return (EOPNOTSUPP);
if (req->bufsize < ETHER_HDR_LEN)
return (ENOMEM);
eh = (struct ether_header *)req->buf;
lladdr = req->lladdr;
req->lladdr_off = 0;
switch (req->family) {
case AF_INET:
etype = htons(ETHERTYPE_IP);
break;
case AF_INET6:
etype = htons(ETHERTYPE_IPV6);
break;
case AF_ARP:
ah = (struct arphdr *)req->hdata;
ah->ar_hrd = htons(ARPHRD_ETHER);
switch(ntohs(ah->ar_op)) {
case ARPOP_REVREQUEST:
case ARPOP_REVREPLY:
etype = htons(ETHERTYPE_REVARP);
break;
case ARPOP_REQUEST:
case ARPOP_REPLY:
default:
etype = htons(ETHERTYPE_ARP);
break;
}
if (req->flags & IFENCAP_FLAG_BROADCAST)
lladdr = ifp->if_broadcastaddr;
break;
default:
return (EAFNOSUPPORT);
}
memcpy(&eh->ether_type, &etype, sizeof(eh->ether_type));
memcpy(eh->ether_dhost, lladdr, ETHER_ADDR_LEN);
memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN);
req->bufsize = sizeof(struct ether_header);
return (0);
}
static int
ether_resolve_addr(struct ifnet *ifp, struct mbuf *m,
const struct sockaddr *dst, struct route *ro, u_char *phdr,
uint32_t *pflags, struct llentry **plle)
{
struct ether_header *eh;
uint32_t lleflags = 0;
int error = 0;
#if defined(INET) || defined(INET6)
uint16_t etype;
#endif
if (plle)
*plle = NULL;
eh = (struct ether_header *)phdr;
switch (dst->sa_family) {
#ifdef INET
case AF_INET:
if ((m->m_flags & (M_BCAST | M_MCAST)) == 0)
error = arpresolve(ifp, 0, m, dst, phdr, &lleflags,
plle);
else {
if (m->m_flags & M_BCAST)
memcpy(eh->ether_dhost, ifp->if_broadcastaddr,
ETHER_ADDR_LEN);
else {
const struct in_addr *a;
a = &(((const struct sockaddr_in *)dst)->sin_addr);
ETHER_MAP_IP_MULTICAST(a, eh->ether_dhost);
}
etype = htons(ETHERTYPE_IP);
memcpy(&eh->ether_type, &etype, sizeof(etype));
memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN);
}
break;
#endif
#ifdef INET6
case AF_INET6:
if ((m->m_flags & M_MCAST) == 0)
error = nd6_resolve(ifp, 0, m, dst, phdr, &lleflags,
plle);
else {
const struct in6_addr *a6;
a6 = &(((const struct sockaddr_in6 *)dst)->sin6_addr);
ETHER_MAP_IPV6_MULTICAST(a6, eh->ether_dhost);
etype = htons(ETHERTYPE_IPV6);
memcpy(&eh->ether_type, &etype, sizeof(etype));
memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN);
}
break;
#endif
default:
if_printf(ifp, "can't handle af%d\n", dst->sa_family);
if (m != NULL)
m_freem(m);
return (EAFNOSUPPORT);
}
if (error == EHOSTDOWN) {
if (ro != NULL && (ro->ro_flags & RT_HAS_GW) != 0)
error = EHOSTUNREACH;
}
if (error != 0)
return (error);
*pflags = RT_MAY_LOOP;
if (lleflags & LLE_IFADDR)
*pflags |= RT_L2_ME;
return (0);
}
/*
* 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,
const struct sockaddr *dst, struct route *ro)
{
int error = 0;
char linkhdr[ETHER_HDR_LEN], *phdr;
struct ether_header *eh;
struct pf_mtag *t;
int loop_copy = 1;
int hlen; /* link layer header length */
uint32_t pflags;
struct llentry *lle = NULL;
int addref = 0;
phdr = NULL;
pflags = 0;
if (ro != NULL) {
/* XXX BPF uses ro_prepend */
if (ro->ro_prepend != NULL) {
phdr = ro->ro_prepend;
hlen = ro->ro_plen;
} else if (!(m->m_flags & (M_BCAST | M_MCAST))) {
if ((ro->ro_flags & RT_LLE_CACHE) != 0) {
lle = ro->ro_lle;
if (lle != NULL &&
(lle->la_flags & LLE_VALID) == 0) {
LLE_FREE(lle);
lle = NULL; /* redundant */
ro->ro_lle = NULL;
}
if (lle == NULL) {
/* if we lookup, keep cache */
addref = 1;
} else
/*
* Notify LLE code that
* the entry was used
* by datapath.
*/
llentry_mark_used(lle);
}
if (lle != NULL) {
phdr = lle->r_linkdata;
hlen = lle->r_hdrlen;
pflags = lle->r_flags;
}
}
}
#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);
if (phdr == NULL) {
/* No prepend data supplied. Try to calculate ourselves. */
phdr = linkhdr;
hlen = ETHER_HDR_LEN;
error = ether_resolve_addr(ifp, m, dst, ro, phdr, &pflags,
addref ? &lle : NULL);
if (addref && lle != NULL)
ro->ro_lle = lle;
if (error != 0)
return (error == EWOULDBLOCK ? 0 : error);
}
if ((pflags & RT_L2_ME) != 0) {
update_mbuf_csumflags(m, m);
return (if_simloop(ifp, m, dst->sa_family, 0));
}
loop_copy = pflags & RT_MAY_LOOP;
/*
* Add local net header. If no space in first mbuf,
* allocate another.
*
* Note that we do prepend regardless of RT_HAS_HEADER flag.
* This is done because BPF code shifts m_data pointer
* to the end of ethernet header prior to calling if_output().
*/
M_PREPEND(m, hlen, M_NOWAIT);
if (m == NULL)
senderr(ENOBUFS);
if ((pflags & RT_HAS_HEADER) == 0) {
eh = mtod(m, struct ether_header *);
memcpy(eh, phdr, hlen);
}
/*
* 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 ((m->m_flags & M_BCAST) && loop_copy && (ifp->if_flags & IFF_SIMPLEX) &&
((t = pf_find_mtag(m)) == NULL || !t->routed)) {
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_NOWAIT)) != NULL) {
update_mbuf_csumflags(m, n);
(void)if_simloop(ifp, n, dst->sa_family, hlen);
} else
if_inc_counter(ifp, IFCOUNTER_IQDROPS, 1);
}
/*
* Bridges require special output handling.
*/
if (ifp->if_bridge) {
BRIDGE_OUTPUT(ifp, m, error);
return (error);
}
#if defined(INET) || defined(INET6)
if (ifp->if_carp &&
(error = (*carp_output_p)(ifp, m, dst)))
goto bad;
#endif
/* Handle ng_ether(4) processing, if any */
if (ifp->if_l2com != 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);
}
static bool
ether_set_pcp(struct mbuf **mp, struct ifnet *ifp, uint8_t pcp)
{
struct ether_header *eh;
eh = mtod(*mp, struct ether_header *);
if (ntohs(eh->ether_type) == ETHERTYPE_VLAN ||
ether_8021q_frame(mp, ifp, ifp, 0, pcp))
return (true);
if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
return (false);
}
/*
* 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)
{
uint8_t pcp;
pcp = ifp->if_pcp;
if (pcp != IFNET_PCP_NONE && ifp->if_type != IFT_L2VLAN &&
!ether_set_pcp(&m, ifp, pcp))
return (0);
if (PFIL_HOOKED_OUT(V_link_pfil_head))
switch (pfil_run_hooks(V_link_pfil_head, &m, ifp, PFIL_OUT,
NULL)) {
case PFIL_DROPPED:
return (EACCES);
case PFIL_CONSUMED:
return (0);
}
#ifdef EXPERIMENTAL
#if defined(INET6) && defined(INET)
/* draft-ietf-6man-ipv6only-flag */
/* Catch ETHERTYPE_IP, and ETHERTYPE_[REV]ARP if we are v6-only. */
if ((ND_IFINFO(ifp)->flags & ND6_IFF_IPV6_ONLY_MASK) != 0) {
struct ether_header *eh;
eh = mtod(m, struct ether_header *);
switch (ntohs(eh->ether_type)) {
case ETHERTYPE_IP:
case ETHERTYPE_ARP:
case ETHERTYPE_REVARP:
m_freem(m);
return (EAFNOSUPPORT);
/* NOTREACHED */
break;
};
}
#endif
#endif
/*
* Queue message on interface, update output statistics if
* successful, and start output if interface not yet active.
*/
return ((ifp->if_transmit)(ifp, m));
}
/*
* Process a received Ethernet packet; the packet is in the
* mbuf chain m with the ethernet header at the front.
*/
static void
ether_input_internal(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
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);
if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
m_freem(m);
return;
}
eh = mtod(m, struct ether_header *);
etype = ntohs(eh->ether_type);
random_harvest_queue_ether(m, sizeof(*m));
#ifdef EXPERIMENTAL
#if defined(INET6) && defined(INET)
/* draft-ietf-6man-ipv6only-flag */
/* Catch ETHERTYPE_IP, and ETHERTYPE_[REV]ARP if we are v6-only. */
if ((ND_IFINFO(ifp)->flags & ND6_IFF_IPV6_ONLY_MASK) != 0) {
switch (etype) {
case ETHERTYPE_IP:
case ETHERTYPE_ARP:
case ETHERTYPE_REVARP:
m_freem(m);
return;
/* NOTREACHED */
break;
};
}
#endif
#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;
if_inc_counter(ifp, IFCOUNTER_IMCASTS, 1);
}
#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;
}
if (!(ifp->if_capenable & IFCAP_HWSTATS))
if_inc_counter(ifp, IFCOUNTER_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 {
CURVNET_RESTORE();
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
if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
CURVNET_RESTORE();
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);
eh = mtod(m, struct ether_header *);
}
M_SETFIB(m, ifp->if_fib);
/* Allow ng_ether(4) to claim this frame. */
if (ifp->if_l2com != 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;
}
eh = mtod(m, struct ether_header *);
}
/*
* 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;
}
eh = mtod(m, struct ether_header *);
}
#if defined(INET) || defined(INET6)
/*
* 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_p)(ifp, 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;
}
ether_demux(ifp, m);
CURVNET_RESTORE();
}
/*
* Ethernet input dispatch; by default, direct dispatch here regardless of
* global configuration. However, if RSS is enabled, hook up RSS affinity
* so that when deferred or hybrid dispatch is enabled, we can redistribute
* load based on RSS.
*
* XXXRW: Would be nice if the ifnet passed up a flag indicating whether or
* not it had already done work distribution via multi-queue. Then we could
* direct dispatch in the event load balancing was already complete and
* handle the case of interfaces with different capabilities better.
*
* XXXRW: Sort of want an M_DISTRIBUTED flag to avoid multiple distributions
* at multiple layers?
*
* XXXRW: For now, enable all this only if RSS is compiled in, although it
* works fine without RSS. Need to characterise the performance overhead
* of the detour through the netisr code in the event the result is always
* direct dispatch.
*/
static void
ether_nh_input(struct mbuf *m)
{
M_ASSERTPKTHDR(m);
KASSERT(m->m_pkthdr.rcvif != NULL,
("%s: NULL interface pointer", __func__));
ether_input_internal(m->m_pkthdr.rcvif, m);
}
static struct netisr_handler ether_nh = {
.nh_name = "ether",
.nh_handler = ether_nh_input,
.nh_proto = NETISR_ETHER,
#ifdef RSS
.nh_policy = NETISR_POLICY_CPU,
.nh_dispatch = NETISR_DISPATCH_DIRECT,
.nh_m2cpuid = rss_m2cpuid,
#else
.nh_policy = NETISR_POLICY_SOURCE,
.nh_dispatch = NETISR_DISPATCH_DIRECT,
#endif
};
static void
ether_init(__unused void *arg)
{
netisr_register(&ether_nh);
}
SYSINIT(ether, SI_SUB_INIT_IF, SI_ORDER_ANY, ether_init, NULL);
static void
vnet_ether_init(__unused void *arg)
{
struct pfil_head_args args;
args.pa_version = PFIL_VERSION;
args.pa_flags = PFIL_IN | PFIL_OUT;
args.pa_type = PFIL_TYPE_ETHERNET;
args.pa_headname = PFIL_ETHER_NAME;
V_link_pfil_head = pfil_head_register(&args);
#ifdef VIMAGE
netisr_register_vnet(&ether_nh);
#endif
}
VNET_SYSINIT(vnet_ether_init, SI_SUB_PROTO_IF, SI_ORDER_ANY,
vnet_ether_init, NULL);
#ifdef VIMAGE
static void
vnet_ether_pfil_destroy(__unused void *arg)
{
pfil_head_unregister(V_link_pfil_head);
}
VNET_SYSUNINIT(vnet_ether_pfil_uninit, SI_SUB_PROTO_PFIL, SI_ORDER_ANY,
vnet_ether_pfil_destroy, NULL);
static void
vnet_ether_destroy(__unused void *arg)
{
netisr_unregister_vnet(&ether_nh);
}
VNET_SYSUNINIT(vnet_ether_uninit, SI_SUB_PROTO_IF, SI_ORDER_ANY,
vnet_ether_destroy, NULL);
#endif
static void
ether_input(struct ifnet *ifp, struct mbuf *m)
{
struct epoch_tracker et;
struct mbuf *mn;
/*
* The drivers are allowed to pass in a chain of packets linked with
* m_nextpkt. We split them up into separate packets here and pass
* them up. This allows the drivers to amortize the receive lock.
*/
CURVNET_SET_QUIET(ifp->if_vnet);
if (__predict_false(ifp->if_flags & IFF_NEEDSEPOCH))
NET_EPOCH_ENTER(et);
while (m) {
mn = m->m_nextpkt;
m->m_nextpkt = NULL;
/*
* We will rely on rcvif being set properly in the deferred
* context, so assert it is correct here.
*/
MPASS((m->m_pkthdr.csum_flags & CSUM_SND_TAG) == 0);
KASSERT(m->m_pkthdr.rcvif == ifp, ("%s: ifnet mismatch m %p "
"rcvif %p ifp %p", __func__, m, m->m_pkthdr.rcvif, ifp));
netisr_dispatch(NETISR_ETHER, m);
m = mn;
}
if (__predict_false(ifp->if_flags & IFF_NEEDSEPOCH))
NET_EPOCH_EXIT(et);
CURVNET_RESTORE();
}
/*
* Upper layer processing for a received Ethernet packet.
*/
void
ether_demux(struct ifnet *ifp, struct mbuf *m)
{
struct ether_header *eh;
int i, isr;
u_short ether_type;
NET_EPOCH_ASSERT();
KASSERT(ifp != NULL, ("%s: NULL interface pointer", __func__));
/* Do not grab PROMISC frames in case we are re-entered. */
if (PFIL_HOOKED_IN(V_link_pfil_head) && !(m->m_flags & M_PROMISC)) {
i = pfil_run_hooks(V_link_pfil_head, &m, ifp, PFIL_IN, NULL);
if (i != 0 || m == NULL)
return;
}
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) {
if_inc_counter(ifp, IFCOUNTER_NOPROTO, 1);
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_clrprotoflags(m);
m_adj(m, ETHER_HDR_LEN);
/*
* Dispatch frame to upper layer.
*/
switch (ether_type) {
#ifdef INET
case ETHERTYPE_IP:
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 INET6
case ETHERTYPE_IPV6:
isr = NETISR_IPV6;
break;
#endif
default:
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 (ifp->if_l2com != 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_NOWAIT);
(*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;
ifp->if_requestencap = ether_requestencap;
#ifdef VIMAGE
ifp->if_reassign = ether_reassign;
#endif
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);
if (ifp->if_hw_addr != NULL)
bcopy(lla, ifp->if_hw_addr, 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, ":");
uuid_ether_add(LLADDR(sdl));
/* Add necessary bits are setup; announce it now. */
EVENTHANDLER_INVOKE(ether_ifattach_event, ifp);
if (IS_DEFAULT_VNET(curvnet))
devctl_notify("ETHERNET", ifp->if_xname, "IFATTACH", NULL);
}
/*
* Perform common duties while detaching an Ethernet interface
*/
void
ether_ifdetach(struct ifnet *ifp)
{
struct sockaddr_dl *sdl;
sdl = (struct sockaddr_dl *)(ifp->if_addr->ifa_addr);
uuid_ether_del(LLADDR(sdl));
if (ifp->if_l2com != NULL) {
KASSERT(ng_ether_detach_p != NULL,
("ng_ether_detach_p is NULL"));
(*ng_ether_detach_p)(ifp);
}
bpfdetach(ifp);
if_detach(ifp);
}
#ifdef VIMAGE
void
ether_reassign(struct ifnet *ifp, struct vnet *new_vnet, char *unused __unused)
{
if (ifp->if_l2com != NULL) {
KASSERT(ng_ether_detach_p != NULL,
("ng_ether_detach_p is NULL"));
(*ng_ether_detach_p)(ifp);
}
if (ng_ether_attach_p != NULL) {
CURVNET_SET_QUIET(new_vnet);
(*ng_ether_attach_p)(ifp);
CURVNET_RESTORE();
}
}
#endif
SYSCTL_DECL(_net_link);
SYSCTL_NODE(_net_link, IFT_ETHER, ether, CTLFLAG_RW, 0, "Ethernet");
#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
default:
ifp->if_init(ifp->if_softc);
break;
}
break;
case SIOCGIFADDR:
bcopy(IF_LLADDR(ifp), &ifr->ifr_addr.sa_data[0],
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;
case SIOCSLANPCP:
error = priv_check(curthread, PRIV_NET_SETLANPCP);
if (error != 0)
break;
if (ifr->ifr_lan_pcp > 7 &&
ifr->ifr_lan_pcp != IFNET_PCP_NONE) {
error = EINVAL;
} else {
ifp->if_pcp = ifr->ifr_lan_pcp;
/* broadcast event about PCP change */
EVENTHANDLER_INVOKE(ifnet_event, ifp, IFNET_EVENT_PCP);
}
break;
case SIOCGLANPCP:
ifr->ifr_lan_pcp = ifp->if_pcp;
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 = NULL;
return 0;
#ifdef INET
case AF_INET:
sin = (struct sockaddr_in *)sa;
if (!IN_MULTICAST(ntohl(sin->sin_addr.s_addr)))
return EADDRNOTAVAIL;
sdl = link_init_sdl(ifp, *llsa, 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 = NULL;
return 0;
}
if (!IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr))
return EADDRNOTAVAIL;
sdl = link_init_sdl(ifp, *llsa, 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 moduledata_t ether_mod = {
.name = "ether",
};
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_NOWAIT);
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);
}
static SYSCTL_NODE(_net_link, IFT_L2VLAN, vlan, CTLFLAG_RW, 0,
"IEEE 802.1Q VLAN");
static SYSCTL_NODE(_net_link_vlan, PF_LINK, link, CTLFLAG_RW, 0,
"for consistency");
VNET_DEFINE_STATIC(int, soft_pad);
#define V_soft_pad VNET(soft_pad)
SYSCTL_INT(_net_link_vlan, OID_AUTO, soft_pad, CTLFLAG_RW | CTLFLAG_VNET,
&VNET_NAME(soft_pad), 0,
"pad short frames before tagging");
/*
* For now, make preserving PCP via an mbuf tag optional, as it increases
* per-packet memory allocations and frees. In the future, it would be
* preferable to reuse ether_vtag for this, or similar.
*/
int vlan_mtag_pcp = 0;
SYSCTL_INT(_net_link_vlan, OID_AUTO, mtag_pcp, CTLFLAG_RW,
&vlan_mtag_pcp, 0,
"Retain VLAN PCP information as packets are passed up the stack");
bool
ether_8021q_frame(struct mbuf **mp, struct ifnet *ife, struct ifnet *p,
uint16_t vid, uint8_t pcp)
{
struct m_tag *mtag;
int n;
uint16_t tag;
static const char pad[8]; /* just zeros */
/*
* Pad the frame to the minimum size allowed if told to.
* This option is in accord with IEEE Std 802.1Q, 2003 Ed.,
* paragraph C.4.4.3.b. It can help to work around buggy
* bridges that violate paragraph C.4.4.3.a from the same
* document, i.e., fail to pad short frames after untagging.
* E.g., a tagged frame 66 bytes long (incl. FCS) is OK, but
* untagging it will produce a 62-byte frame, which is a runt
* and requires padding. There are VLAN-enabled network
* devices that just discard such runts instead or mishandle
* them somehow.
*/
if (V_soft_pad && p->if_type == IFT_ETHER) {
for (n = ETHERMIN + ETHER_HDR_LEN - (*mp)->m_pkthdr.len;
n > 0; n -= sizeof(pad)) {
if (!m_append(*mp, min(n, sizeof(pad)), pad))
break;
}
if (n > 0) {
m_freem(*mp);
*mp = NULL;
if_printf(ife, "cannot pad short frame");
return (false);
}
}
/*
* If underlying interface can do VLAN tag insertion itself,
* just pass the packet along. However, we need some way to
* tell the interface where the packet came from so that it
* knows how to find the VLAN tag to use, so we attach a
* packet tag that holds it.
*/
if (vlan_mtag_pcp && (mtag = m_tag_locate(*mp, MTAG_8021Q,
MTAG_8021Q_PCP_OUT, NULL)) != NULL)
tag = EVL_MAKETAG(vid, *(uint8_t *)(mtag + 1), 0);
else
tag = EVL_MAKETAG(vid, pcp, 0);
if (p->if_capenable & IFCAP_VLAN_HWTAGGING) {
(*mp)->m_pkthdr.ether_vtag = tag;
(*mp)->m_flags |= M_VLANTAG;
} else {
*mp = ether_vlanencap(*mp, tag);
if (*mp == NULL) {
if_printf(ife, "unable to prepend 802.1Q header");
return (false);
}
}
return (true);
}
/*
* Allocate an address from the FreeBSD Foundation OUI. This uses a
* cryptographic hash function on the containing jail's UUID and the interface
* name to attempt to provide a unique but stable address. Pseudo-interfaces
* which require a MAC address should use this function to allocate
* non-locally-administered addresses.
*/
void
ether_gen_addr(struct ifnet *ifp, struct ether_addr *hwaddr)
{
#define ETHER_GEN_ADDR_BUFSIZ HOSTUUIDLEN + IFNAMSIZ + 2
SHA1_CTX ctx;
char buf[ETHER_GEN_ADDR_BUFSIZ];
char uuid[HOSTUUIDLEN + 1];
uint64_t addr;
int i, sz;
char digest[SHA1_RESULTLEN];
getcredhostuuid(curthread->td_ucred, uuid, sizeof(uuid));
sz = snprintf(buf, ETHER_GEN_ADDR_BUFSIZ, "%s-%s", uuid, ifp->if_xname);
SHA1Init(&ctx);
SHA1Update(&ctx, buf, sz);
SHA1Final(digest, &ctx);
addr = ((digest[0] << 16) | (digest[1] << 8) | digest[2]) &
OUI_FREEBSD_GENERATED_MASK;
addr = OUI_FREEBSD(addr);
for (i = 0; i < ETHER_ADDR_LEN; ++i) {
hwaddr->octet[i] = addr >> ((ETHER_ADDR_LEN - i - 1) * 8) &
0xFF;
}
}
DECLARE_MODULE(ether, ether_mod, SI_SUB_INIT_IF, SI_ORDER_ANY);
MODULE_VERSION(ether, 1);
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