Add a pointer to the relevant PR for future reference. The whole comment
will be OK to remove as soon as the general solution is applied.
PR: kern/105943
The symptoms were that outgoing DHCP requests for diskless kernels
had the IP header corrupt. After long investigations, the source of
the problem was found in ether_output() - for SIMPLEX interfaces
and broadcast traffic, a copy of the packet is passed back to the kernel
through if_simloop(). However if_simloop() modifies the mbuf, while
the copy obtained through m_copym() is a readonly one.
The bug has been there forever, but it has been triggered only recently
by a change in sosend_dgram() which passed down mbufs with sufficient
space to prepend the header.
This fix is trivial - use m_dup() instead of m_copy() to create
the copy. As an alternative, we could try and modify if_simloop()
to play safely with readonly mbufs, but i don't think it is worthwhile
because 1) this is a relatively infrequent code path so we do not need
to worry too much about performance, and 2) the cost of doing an
extra m_pullup in if_simloop() is probably the same as doing the
copy of the cluster, anyways.
MFC after: 1 week
processing are forced to toggle this functionality when the card
is put in and out of promiscuous mode. The main reason for this
is because the hardware strips the VLAN tag, making it impossible
for the tag information to show up in network diagnostic tools like
tcpdump(1).
This change introduces ether_vlan_mtap(), which is called if the
mbuf has M_VLANTAG set. VLAN information is extracted from the
mbuf and inserted into a stack allocated ether vlan header which
is then inserted through the bpf machinery via bpf_mtap2(). The
original mbuf's data pointer and lengths are temporarily adjusted
to eliminate the original Ethernet header for the duration of the
tap operation. This should have no long term effects on the mbuf.
Also, define a new macro, ETHER_BPF_MTAP which should be used
by drivers which support hardware offload of VLAN tag processing.
The fixes for the relevant drivers will follow shortly.
Discussed with: rwatson, andre, jhb (and others)
Much feedback from: sam, ru
MFC after: 1 month [1]
[1] The version that is eventually MFCed will be somewhat
different then this, as there has been significant work
done to the VLAN code in HEAD.
begun with a repo-copy of mac.h to mac_framework.h. sys/mac.h now
contains the userspace and user<->kernel API and definitions, with all
in-kernel interfaces moved to mac_framework.h, which is now included
across most of the kernel instead.
This change is the first step in a larger cleanup and sweep of MAC
Framework interfaces in the kernel, and will not be MFC'd.
Obtained from: TrustedBSD Project
Sponsored by: SPARTA
re-organizing the monitor return logic. We perform interface monitoring
checks after we have determined if the CRC is still on the packet, if
it is, m_adj() is called which will adjust the packet length. This
ensures that we are not including CRC lengths in the byte counters for
each packet.
Discussed with: andre, glebius
work by yar, thompsa and myself. The checksum offloading part also involves
work done by Mihail Balikov.
The most important changes:
o Instead of global linked list of all vlan softc use a per-trunk
hash. The size of hash is dynamically adjusted, depending on
number of entries. This changes struct ifnet, replacing counter
of vlans with a pointer to trunk structure. This change is an
improvement for setups with big number of VLANs, several interfaces
and several CPUs. It is a small regression for a setup with a single
VLAN interface.
An alternative to dynamic hash is a per-trunk static array with
4096 entries, which is a compile time option - VLAN_ARRAY. In my
experiments the array is not an improvement, probably because such
a big trunk structure doesn't fit into CPU cache.
o Introduce an UMA zone for VLAN tags. Since drivers depend on it,
the zone is declared in kern_mbuf.c, not in optional vlan(4) driver.
This change is a big improvement for any setup utilizing vlan(4).
o Use rwlock(9) instead of mutex(9) for locking. We are the first
ones to do this! :)
o Some drivers can do hardware VLAN tagging + hardware checksum
offloading. Add an infrastructure for this. Whenever vlan(4) is
attached to a parent or parent configuration is changed, the flags
on vlan(4) interface are updated.
In collaboration with: yar, thompsa
In collaboration with: Mihail Balikov <mihail.balikov interbgc.com>
may have changed by m_pullup() during fastforward processing.
While this is a bug it is actually never triggered in real world
situations and it is not remotely exploitable.
Found by: Coverity Prevent(tm)
Coverity ID: CID780
Sponsored by: TCP/IP Optimization Fundraise 2005
span ports when they disappear. The span port does not have a pointer to the
softc so revert r1.31 and bring back the softc linked-list.
MFC after: 2 weeks
rather than in ifindex_table[]; all (except one) accesses are
through ifp anyway. IF_LLADDR() works faster, and all (except
one) ifaddr_byindex() users were converted to use ifp->if_addr.
- Stop storing a (pointer to) Ethernet address in "struct arpcom",
and drop the IFP2ENADDR() macro; all users have been converted
to use IF_LLADDR() instead.
copy of Ethernet address.
- Change iso88025_ifattach() and fddi_ifattach() to accept MAC
address as an argument, similar to ether_ifattach(), to make
this work.
- move the function pointer definitions to if_bridgevar.h
- move most of the logic to the new BRIDGE_INPUT and BRIDGE_OUTPUT macros
- remove unneeded functions from if_bridgevar.h and sort a little.
Use bridge_ifdetach() to notify the bridge that a member has been detached. The
bridge can then remove it from its interface list and not try to send out via a
dead pointer.
http://lists.freebsd.org/pipermail/cvs-src/2004-October/033496.html
The same problem applies to if_bridge(4), too.
- Copy-and-paste the if_bridge(4) related block from
if_ethersubr.c to ng_ether.c
- Add XXXs, so that copy-and-paste would be noticed by
any future editors of this code.
- Also add XXXs near if_bridge(4) declarations.
Silence from: thompsa
replacement and has additional features which make it superior.
Discussed on: -arch
Reviewed by: thompsa
X-MFC-after: never (RELENG_6 as transition period)
assigned to the interface.
IPv6 auto-configuration is disabled. An IPv6 link-local address has a
link-local scope within one link, the spec is unclear for the bridge case and
it may cause scope violation.
An address can be assigned in the usual way;
ifconfig bridge0 inet6 xxxx:...
Tested by: bmah
Reviewed by: ume (netinet6)
Approved by: mlaier (mentor)
MFC after: 1 week
IFF_DRV_RUNNING, as well as the move from ifnet.if_flags to
ifnet.if_drv_flags. Device drivers are now responsible for
synchronizing access to these flags, as they are in if_drv_flags. This
helps prevent races between the network stack and device driver in
maintaining the interface flags field.
Many __FreeBSD__ and __FreeBSD_version checks maintained and continued;
some less so.
Reviewed by: pjd, bz
MFC after: 7 days
ifp->if_resolvemulti(), do so with M_NOWAIT rather than M_WAITOK, so
that a mutex can be held over the call. In the FDDI code, add a
missing M_ZERO. Consumers are already aware that if_resolvemulti()
can fail.
MFC after: 1 week
struct ifnet or the layer 2 common structure it was embedded in have
been replaced with a struct ifnet pointer to be filled by a call to the
new function, if_alloc(). The layer 2 common structure is also allocated
via if_alloc() based on the interface type. It is hung off the new
struct ifnet member, if_l2com.
This change removes the size of these structures from the kernel ABI and
will allow us to better manage them as interfaces come and go.
Other changes of note:
- Struct arpcom is no longer referenced in normal interface code.
Instead the Ethernet address is accessed via the IFP2ENADDR() macro.
To enforce this ac_enaddr has been renamed to _ac_enaddr.
- The second argument to ether_ifattach is now always the mac address
from driver private storage rather than sometimes being ac_enaddr.
Reviewed by: sobomax, sam
hosts to share an IP address, providing high availability and load
balancing.
Original work on CARP done by Michael Shalayeff, with many
additions by Marco Pfatschbacher and Ryan McBride.
FreeBSD port done solely by Max Laier.
Patch by: mlaier
Obtained from: OpenBSD (mickey, mcbride)
a packet has VLAN mbuf tag attached. This is faster to check than
m_tag_locate(), and allows us to use the tags in non-vlan(4) VLAN
producers.
The first argument to VLAN_OUTPUT_TAG() is now unused but retained
for backward compatibility.
While here, embellish a fix in rev. 1.174 of if_ethersubr.c -- it
now checks for packets with VLAN (mbuf) tags, and it should now
be possible to bridge(4) on vlan(4)'s whose parent interfaces
support VLAN decapsulation in hardware.
Reviewed by: sam
driver did VLAN decapsulation in hardware, we were passing a frame
as if it came for the parent (non-VLAN) interface. Stop this from
happening.
Reminded by: glebius
Security: This could pose a security risk in some setups
- ip_fw_chk() returns action as function return value. Field retval is
removed from args structure. Action is not flag any more. It is one
of integer constants.
- Any action-specific cookies are returned either in new "cookie" field
in args structure (dummynet, future netgraph glue), or in mbuf tag
attached to packet (divert, tee, some future action).
o Convert parsing of return value from ip_fw_chk() in ipfw_check_{in,out}()
to a switch structure, so that the functions are more readable, and a future
actions can be added with less modifications.
Approved by: andre
MFC after: 2 months
- push all bridge logic from if_ethersubr.c into bridge.c
make bridge_in() return mbuf pointer (or NULL).
- call only bridge_in() from ether_input(), after ng_ether_input()
was optinally called.
- call bridge_in() from ng_ether_rcv_upper().
Long description: http://lists.freebsd.org/mailman/htdig/freebsd-net/2004-May/003881.html
Reported by: Jian-Wei Wang <jwwang at FreeBSD.csie.NCTU.edu.tw>
Tested by: myself, Sergey Lyubka
Reviewed by: sam
Approved by: julian (mentor)
MFC after: 2 months
device drivers to declare that the ifp->if_start() method implemented
by the driver requires Giant in order to operate correctly.
Add a 'struct task' to 'struct ifnet' that can be used to execute a
deferred ifp->if_start() in the event that if_start needs to be called
in a Giant-free environment. To do this, introduce if_start(), a
wrapper function for ifp->if_start(). If the interface can run MPSAFE,
it directly dispatches into the interface start routine. If it can't
run MPSAFE, we're running with debug.mpsafenet != 0, and Giant isn't
currently held, the task is queued to execute in a swi holding Giant
via if_start_deferred().
Modify if_handoff() to use if_start() instead of direct dispatch.
Modify 802.11 to use if_start() instead of direct dispatch.
This is intended to provide increased compatibility for non-MPSAFE
network device drivers in the presence of Giant-free operation via
asynchronous dispatch. However, this commit does not mark any network
interfaces as IFF_NEEDSGIANT.
only allow this to be further processed when bridging is active on
that interface, but also if the current packet has a VLAN tag and
VLANs are active on our interface. This gives the VLAN layers a
chance to also consider the packet (and perhaps drop it instead of the
main dispatcher).
This fixes a situation where bridging was only active on VLAN
interfaces but ether_demux() called on behalf of the main interface
had already thrown the packet away.
MFC after: 4 weeks
