freebsd-skq/sys/net/if_ethersubr.c
jhb 5518ae8169 Restructure mbuf send tags to provide stronger guarantees.
- Perform ifp mismatch checks (to determine if a send tag is allocated
  for a different ifp than the one the packet is being output on), in
  ip_output() and ip6_output().  This avoids sending packets with send
  tags to ifnet drivers that don't support send tags.

  Since we are now checking for ifp mismatches before invoking
  if_output, we can now try to allocate a new tag before invoking
  if_output sending the original packet on the new tag if allocation
  succeeds.

  To avoid code duplication for the fragment and unfragmented cases,
  add ip_output_send() and ip6_output_send() as wrappers around
  if_output and nd6_output_ifp, respectively.  All of the logic for
  setting send tags and dealing with send tag-related errors is done
  in these wrapper functions.

  For pseudo interfaces that wrap other network interfaces (vlan and
  lagg), wrapper send tags are now allocated so that ip*_output see
  the wrapper ifp as the ifp in the send tag.  The if_transmit
  routines rewrite the send tags after performing an ifp mismatch
  check.  If an ifp mismatch is detected, the transmit routines fail
  with EAGAIN.

- To provide clearer life cycle management of send tags, especially
  in the presence of vlan and lagg wrapper tags, add a reference count
  to send tags managed via m_snd_tag_ref() and m_snd_tag_rele().
  Provide a helper function (m_snd_tag_init()) for use by drivers
  supporting send tags.  m_snd_tag_init() takes care of the if_ref
  on the ifp meaning that code alloating send tags via if_snd_tag_alloc
  no longer has to manage that manually.  Similarly, m_snd_tag_rele
  drops the refcount on the ifp after invoking if_snd_tag_free when
  the last reference to a send tag is dropped.

  This also closes use after free races if there are pending packets in
  driver tx rings after the socket is closed (e.g. from tcpdrop).

  In order for m_free to work reliably, add a new CSUM_SND_TAG flag in
  csum_flags to indicate 'snd_tag' is set (rather than 'rcvif').
  Drivers now also check this flag instead of checking snd_tag against
  NULL.  This avoids false positive matches when a forwarded packet
  has a non-NULL rcvif that was treated as a send tag.

- cxgbe was relying on snd_tag_free being called when the inp was
  detached so that it could kick the firmware to flush any pending
  work on the flow.  This is because the driver doesn't require ACK
  messages from the firmware for every request, but instead does a
  kind of manual interrupt coalescing by only setting a flag to
  request a completion on a subset of requests.  If all of the
  in-flight requests don't have the flag when the tag is detached from
  the inp, the flow might never return the credits.  The current
  snd_tag_free command issues a flush command to force the credits to
  return.  However, the credit return is what also frees the mbufs,
  and since those mbufs now hold references on the tag, this meant
  that snd_tag_free would never be called.

  To fix, explicitly drop the mbuf's reference on the snd tag when the
  mbuf is queued in the firmware work queue.  This means that once the
  inp's reference on the tag goes away and all in-flight mbufs have
  been queued to the firmware, tag's refcount will drop to zero and
  snd_tag_free will kick in and send the flush request.  Note that we
  need to avoid doing this in the middle of ethofld_tx(), so the
  driver grabs a temporary reference on the tag around that loop to
  defer the free to the end of the function in case it sends the last
  mbuf to the queue after the inp has dropped its reference on the
  tag.

- mlx5 preallocates send tags and was using the ifp pointer even when
  the send tag wasn't in use.  Explicitly use the ifp from other data
  structures instead.

- Sprinkle some assertions in various places to assert that received
  packets don't have a send tag, and that other places that overwrite
  rcvif (e.g. 802.11 transmit) don't clobber a send tag pointer.

Reviewed by:	gallatin, hselasky, rgrimes, ae
Sponsored by:	Netflix
Differential Revision:	https://reviews.freebsd.org/D20117
2019-05-24 22:30:40 +00:00

1445 lines
36 KiB
C

/*-
* 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 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.
*/
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));
CURVNET_SET_QUIET(ifp->if_vnet);
netisr_dispatch(NETISR_ETHER, m);
CURVNET_RESTORE();
m = mn;
}
}
/*
* 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;
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);