Commit Graph

102 Commits

Author SHA1 Message Date
Julian Elischer
b53c8130e5 Another V_ forgotten 2008-08-25 05:49:16 +00:00
Bjoern A. Zeeb
603724d3ab Commit step 1 of the vimage project, (network stack)
virtualization work done by Marko Zec (zec@).

This is the first in a series of commits over the course
of the next few weeks.

Mark all uses of global variables to be virtualized
with a V_ prefix.
Use macros to map them back to their global names for
now, so this is a NOP change only.

We hope to have caught at least 85-90% of what is needed
so we do not invalidate a lot of outstanding patches again.

Obtained from:	//depot/projects/vimage-commit2/...
Reviewed by:	brooks, des, ed, mav, julian,
		jamie, kris, rwatson, zec, ...
		(various people I forgot, different versions)
		md5 (with a bit of help)
Sponsored by:	NLnet Foundation, The FreeBSD Foundation
X-MFC after:	never
V_Commit_Message_Reviewed_By:	more people than the patch
2008-08-17 23:27:27 +00:00
Julian Elischer
8b07e49a00 Add code to allow the system to handle multiple routing tables.
This particular implementation is designed to be fully backwards compatible
and to be MFC-able to 7.x (and 6.x)

Currently the only protocol that can make use of the multiple tables is IPv4
Similar functionality exists in OpenBSD and Linux.

From my notes:

-----

  One thing where FreeBSD has been falling behind, and which by chance I
  have some time to work on is "policy based routing", which allows
  different
  packet streams to be routed by more than just the destination address.

  Constraints:
  ------------

  I want to make some form of this available in the 6.x tree
  (and by extension 7.x) , but FreeBSD in general needs it so I might as
  well do it in -current and back port the portions I need.

  One of the ways that this can be done is to have the ability to
  instantiate multiple kernel routing tables (which I will now
  refer to as "Forwarding Information Bases" or "FIBs" for political
  correctness reasons). Which FIB a particular packet uses to make
  the next hop decision can be decided by a number of mechanisms.
  The policies these mechanisms implement are the "Policies" referred
  to in "Policy based routing".

  One of the constraints I have if I try to back port this work to
  6.x is that it must be implemented as a EXTENSION to the existing
  ABIs in 6.x so that third party applications do not need to be
  recompiled in timespan of the branch.

  This first version will not have some of the bells and whistles that
  will come with later versions. It will, for example, be limited to 16
  tables in the first commit.
  Implementation method, Compatible version. (part 1)
  -------------------------------
  For this reason I have implemented a "sufficient subset" of a
  multiple routing table solution in Perforce, and back-ported it
  to 6.x. (also in Perforce though not  always caught up with what I
  have done in -current/P4). The subset allows a number of FIBs
  to be defined at compile time (8 is sufficient for my purposes in 6.x)
  and implements the changes needed to allow IPV4 to use them. I have not
  done the changes for ipv6 simply because I do not need it, and I do not
  have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it.

  Other protocol families are left untouched and should there be
  users with proprietary protocol families, they should continue to work
  and be oblivious to the existence of the extra FIBs.

  To understand how this is done, one must know that the current FIB
  code starts everything off with a single dimensional array of
  pointers to FIB head structures (One per protocol family), each of
  which in turn points to the trie of routes available to that family.

  The basic change in the ABI compatible version of the change is to
  extent that array to be a 2 dimensional array, so that
  instead of protocol family X looking at rt_tables[X] for the
  table it needs, it looks at rt_tables[Y][X] when for all
  protocol families except ipv4 Y is always 0.
  Code that is unaware of the change always just sees the first row
  of the table, which of course looks just like the one dimensional
  array that existed before.

  The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign()
  are all maintained, but refer only to the first row of the array,
  so that existing callers in proprietary protocols can continue to
  do the "right thing".
  Some new entry points are added, for the exclusive use of ipv4 code
  called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(),
  which have an extra argument which refers the code to the correct row.

  In addition, there are some new entry points (currently called
  rtalloc_fib() and friends) that check the Address family being
  looked up and call either rtalloc() (and friends) if the protocol
  is not IPv4 forcing the action to row 0 or to the appropriate row
  if it IS IPv4 (and that info is available). These are for calling
  from code that is not specific to any particular protocol. The way
  these are implemented would change in the non ABI preserving code
  to be added later.

  One feature of the first version of the code is that for ipv4,
  the interface routes show up automatically on all the FIBs, so
  that no matter what FIB you select you always have the basic
  direct attached hosts available to you. (rtinit() does this
  automatically).

  You CAN delete an interface route from one FIB should you want
  to but by default it's there. ARP information is also available
  in each FIB. It's assumed that the same machine would have the
  same MAC address, regardless of which FIB you are using to get
  to it.

  This brings us as to how the correct FIB is selected for an outgoing
  IPV4 packet.

  Firstly, all packets have a FIB associated with them. if nothing
  has been done to change it, it will be FIB 0. The FIB is changed
  in the following ways.

  Packets fall into one of a number of classes.

  1/ locally generated packets, coming from a socket/PCB.
     Such packets select a FIB from a number associated with the
     socket/PCB. This in turn is inherited from the process,
     but can be changed by a socket option. The process in turn
     inherits it on fork. I have written a utility call setfib
     that acts a bit like nice..

         setfib -3 ping target.example.com # will use fib 3 for ping.

     It is an obvious extension to make it a property of a jail
     but I have not done so. It can be achieved by combining the setfib and
     jail commands.

  2/ packets received on an interface for forwarding.
     By default these packets would use table 0,
     (or possibly a number settable in a sysctl(not yet)).
     but prior to routing the firewall can inspect them (see below).
     (possibly in the future you may be able to associate a FIB
     with packets received on an interface..  An ifconfig arg, but not yet.)

  3/ packets inspected by a packet classifier, which can arbitrarily
     associate a fib with it on a packet by packet basis.
     A fib assigned to a packet by a packet classifier
     (such as ipfw) would over-ride a fib associated by
     a more default source. (such as cases 1 or 2).

  4/ a tcp listen socket associated with a fib will generate
     accept sockets that are associated with that same fib.

  5/ Packets generated in response to some other packet (e.g. reset
     or icmp packets). These should use the FIB associated with the
     packet being reponded to.

  6/ Packets generated during encapsulation.
     gif, tun and other tunnel interfaces will encapsulate using the FIB
     that was in effect withthe proces that set up the tunnel.
     thus setfib 1 ifconfig gif0 [tunnel instructions]
     will set the fib for the tunnel to use to be fib 1.

  Routing messages would be associated with their
  process, and thus select one FIB or another.
  messages from the kernel would be associated with the fib they
  refer to and would only be received by a routing socket associated
  with that fib. (not yet implemented)

  In addition Netstat has been edited to be able to cope with the
  fact that the array is now 2 dimensional. (It looks in system
  memory using libkvm (!)). Old versions of netstat see only the first FIB.

  In addition two sysctls are added to give:
  a) the number of FIBs compiled in (active)
  b) the default FIB of the calling process.

  Early testing experience:
  -------------------------

  Basically our (IronPort's) appliance does this functionality already
  using ipfw fwd but that method has some drawbacks.

  For example,
  It can't fully simulate a routing table because it can't influence the
  socket's choice of local address when a connect() is done.

  Testing during the generating of these changes has been
  remarkably smooth so far. Multiple tables have co-existed
  with no notable side effects, and packets have been routes
  accordingly.

  ipfw has grown 2 new keywords:

  setfib N ip from anay to any
  count ip from any to any fib N

  In pf there seems to be a requirement to be able to give symbolic names to the
  fibs but I do not have that capacity. I am not sure if it is required.

  SCTP has interestingly enough built in support for this, called VRFs
  in Cisco parlance. it will be interesting to see how that handles it
  when it suddenly actually does something.

  Where to next:
  --------------------

  After committing the ABI compatible version and MFCing it, I'd
  like to proceed in a forward direction in -current. this will
  result in some roto-tilling in the routing code.

  Firstly: the current code's idea of having a separate tree per
  protocol family, all of the same format, and pointed to by the
  1 dimensional array is a bit silly. Especially when one considers that
  there is code that makes assumptions about every protocol having the
  same internal structures there. Some protocols don't WANT that
  sort of structure. (for example the whole idea of a netmask is foreign
  to appletalk). This needs to be made opaque to the external code.

  My suggested first change is to add routing method pointers to the
  'domain' structure, along with information pointing the data.
  instead of having an array of pointers to uniform structures,
  there would be an array pointing to the 'domain' structures
  for each protocol address domain (protocol family),
  and the methods this reached would be called. The methods would have
  an argument that gives FIB number, but the protocol would be free
  to ignore it.

  When the ABI can be changed it raises the possibilty of the
  addition of a fib entry into the "struct route". Currently,
  the structure contains the sockaddr of the desination, and the resulting
  fib entry. To make this work fully, one could add a fib number
  so that given an address and a fib, one can find the third element, the
  fib entry.

  Interaction with the ARP layer/ LL layer would need to be
  revisited as well. Qing Li has been working on this already.

  This work was sponsored by Ironport Systems/Cisco

Reviewed by:    several including rwatson, bz and mlair (parts each)
Obtained from:  Ironport systems/Cisco
2008-05-09 23:03:00 +00:00
Bruce M Simpson
71498f308b Import rewrite of IPv4 socket multicast layer to support source-specific
and protocol-independent host mode multicast. The code is written to
accomodate IPv6, IGMPv3 and MLDv2 with only a little additional work.

This change only pertains to FreeBSD's use as a multicast end-station and
does not concern multicast routing; for an IGMPv3/MLDv2 router
implementation, consider the XORP project.

The work is based on Wilbert de Graaf's IGMPv3 code drop for FreeBSD 4.6,
which is available at: http://www.kloosterhof.com/wilbert/igmpv3.html

Summary
 * IPv4 multicast socket processing is now moved out of ip_output.c
   into a new module, in_mcast.c.
 * The in_mcast.c module implements the IPv4 legacy any-source API in
   terms of the protocol-independent source-specific API.
 * Source filters are lazy allocated as the common case does not use them.
   They are part of per inpcb state and are covered by the inpcb lock.
 * struct ip_mreqn is now supported to allow applications to specify
   multicast joins by interface index in the legacy IPv4 any-source API.
 * In UDP, an incoming multicast datagram only requires that the source
   port matches the 4-tuple if the socket was already bound by source port.
   An unbound socket SHOULD be able to receive multicasts sent from an
   ephemeral source port.
 * The UDP socket multicast filter mode defaults to exclusive, that is,
   sources present in the per-socket list will be blocked from delivery.
 * The RFC 3678 userland functions have been added to libc: setsourcefilter,
   getsourcefilter, setipv4sourcefilter, getipv4sourcefilter.
 * Definitions for IGMPv3 are merged but not yet used.
 * struct sockaddr_storage is now referenced from <netinet/in.h>. It
   is therefore defined there if not already declared in the same way
   as for the C99 types.
 * The RFC 1724 hack (specify 0.0.0.0/8 addresses to IP_MULTICAST_IF
   which are then interpreted as interface indexes) is now deprecated.
 * A patch for the Rhyolite.com routed in the FreeBSD base system
   is available in the -net archives. This only affects individuals
   running RIPv1 or RIPv2 via point-to-point and/or unnumbered interfaces.
 * Make IPv6 detach path similar to IPv4's in code flow; functionally same.
 * Bump __FreeBSD_version to 700048; see UPDATING.

This work was financially supported by another FreeBSD committer.

Obtained from:  p4://bms_netdev
Submitted by:   Wilbert de Graaf (original work)
Reviewed by:    rwatson (locking), silence from fenner,
		net@ (but with encouragement)
2007-06-12 16:24:56 +00:00
Andre Oppermann
beaa515e95 Some local and style(9) cleanups. 2007-04-04 15:30:31 +00:00
Bruce M Simpson
3548bfc964 Fix a long-standing limitation in IPv4 multicast group membership.
By making the imo_membership array a dynamically allocated vector,
this minimizes disruption to existing IPv4 multicast code. This
change breaks the ABI for the kernel module ip_mroute.ko, and may
cause a small amount of churn for folks working on the IGMPv3 merge.

Previously, sockets were subject to a compile-time limitation on
the number of IPv4 group memberships, which was hard-coded to 20.
The imo_membership relationship, however, is 1:1 with regards to
a tuple of multicast group address and interface address. Users who
ran routing protocols such as OSPF ran into this limitation on machines
with a large system interface tree.
2006-05-14 14:22:49 +00:00
Andre Oppermann
c444cdded2 Move MAX_IPOPTLEN and struct ipoption back into ip_var.h as
userland programs depend on it.

Pointed out by:	le
Sponsored by:	TCP/IP Optimization Fundraise 2005
2005-11-19 14:01:32 +00:00
Andre Oppermann
ef39adf007 Consolidate all IP Options handling functions into ip_options.[ch] and
include ip_options.h into all files making use of IP Options functions.

From ip_input.c rev 1.306:
  ip_dooptions(struct mbuf *m, int pass)
  save_rte(m, option, dst)
  ip_srcroute(m0)
  ip_stripoptions(m, mopt)

From ip_output.c rev 1.249:
  ip_insertoptions(m, opt, phlen)
  ip_optcopy(ip, jp)
  ip_pcbopts(struct inpcb *inp, int optname, struct mbuf *m)

No functional changes in this commit.

Discussed with:	rwatson
Sponsored by:	TCP/IP Optimization Fundraise 2005
2005-11-18 20:12:40 +00:00
Andrew Thompson
2fcb030ad5 Check the alignment of the IP header before passing the packet up to the
packet filter. This would cause a panic on architectures that require strict
alignment such as sparc64 (tier1) and ia64/ppc (tier2).

This adds two new macros that check the alignment, these are compile time
dependent on __NO_STRICT_ALIGNMENT which is set for i386 and amd64 where
alignment isn't need so the cost is avoided.

 IP_HDR_ALIGNED_P()
 IP6_HDR_ALIGNED_P()

Move bridge_ip_checkbasic()/bridge_ip6_checkbasic() up so that the alignment
is checked for ipfw and dummynet too.

PR:		ia64/81284
Obtained from:	NetBSD
Approved by:	re (dwhite), mlaier (mentor)
2005-07-02 23:13:31 +00:00
Warner Losh
c398230b64 /* -> /*- for license, minor formatting changes 2005-01-07 01:45:51 +00:00
Mike Silbersack
5f311da2cc Port randomization leads to extremely fast port reuse at high
connection rates, which is causing problems for some users.

To retain the security advantage of random ports and ensure
correct operation for high connection rate users, disable
port randomization during periods of high connection rates.

Whenever the connection rate exceeds randomcps (10 by default),
randomization will be disabled for randomtime (45 by default)
seconds.  These thresholds may be tuned via sysctl.

Many thanks to Igor Sysoev, who proved the necessity of this
change and tested many preliminary versions of the patch.

MFC After:	20 seconds
2005-01-02 01:50:57 +00:00
Andre Oppermann
de38924dc0 Support for dynamically loadable and unloadable IP protocols in the ipmux.
With pr_proto_register() it has become possible to dynamically load protocols
within the PF_INET domain.  However the PF_INET domain has a second important
structure called ip_protox[] that is derived from the 'struct protosw inetsw[]'
and takes care of the de-multiplexing of the various protocols that ride on
top of IP packets.

The functions ipproto_[un]register() allow to dynamically adjust the ip_protox[]
array mux in a consistent and easy way.  To register a protocol within
ip_protox[] the existence of a corresponding and matching protocol definition
in inetsw[] is required.  The function does not allow to overwrite an already
registered protocol.  The unregister function simply replaces the mux slot with
the default index pointer to IPPROTO_RAW as it was previously.
2004-10-19 15:45:57 +00:00
Andre Oppermann
e098266191 Remove the last two global variables that are used to store packet state while
it travels through the IP stack.  This wasn't much of a problem because IP
source routing is disabled by default but when enabled together with SMP and
preemption it would have very likely cross-corrupted the IP options in transit.

The IP source route options of a packet are now stored in a mtag instead of the
global variable.
2004-09-15 20:13:26 +00:00
Andre Oppermann
c21fd23260 Always compile PFIL_HOOKS into the kernel and remove the associated kernel
compile option.  All FreeBSD packet filters now use the PFIL_HOOKS API and
thus it becomes a standard part of the network stack.

If no hooks are connected the entire packet filter hooks section and related
activities are jumped over.  This removes any performance impact if no hooks
are active.

Both OpenBSD and DragonFlyBSD have integrated PFIL_HOOKS permanently as well.
2004-08-27 15:16:24 +00:00
Andre Oppermann
9b932e9e04 Convert ipfw to use PFIL_HOOKS. This is change is transparent to userland
and preserves the ipfw ABI.  The ipfw core packet inspection and filtering
functions have not been changed, only how ipfw is invoked is different.

However there are many changes how ipfw is and its add-on's are handled:

 In general ipfw is now called through the PFIL_HOOKS and most associated
 magic, that was in ip_input() or ip_output() previously, is now done in
 ipfw_check_[in|out]() in the ipfw PFIL handler.

 IPDIVERT is entirely handled within the ipfw PFIL handlers.  A packet to
 be diverted is checked if it is fragmented, if yes, ip_reass() gets in for
 reassembly.  If not, or all fragments arrived and the packet is complete,
 divert_packet is called directly.  For 'tee' no reassembly attempt is made
 and a copy of the packet is sent to the divert socket unmodified.  The
 original packet continues its way through ip_input/output().

 ipfw 'forward' is done via m_tag's.  The ipfw PFIL handlers tag the packet
 with the new destination sockaddr_in.  A check if the new destination is a
 local IP address is made and the m_flags are set appropriately.  ip_input()
 and ip_output() have some more work to do here.  For ip_input() the m_flags
 are checked and a packet for us is directly sent to the 'ours' section for
 further processing.  Destination changes on the input path are only tagged
 and the 'srcrt' flag to ip_forward() is set to disable destination checks
 and ICMP replies at this stage.  The tag is going to be handled on output.
 ip_output() again checks for m_flags and the 'ours' tag.  If found, the
 packet will be dropped back to the IP netisr where it is going to be picked
 up by ip_input() again and the directly sent to the 'ours' section.  When
 only the destination changes, the route's 'dst' is overwritten with the
 new destination from the forward m_tag.  Then it jumps back at the route
 lookup again and skips the firewall check because it has been marked with
 M_SKIP_FIREWALL.  ipfw 'forward' has to be compiled into the kernel with
 'option IPFIREWALL_FORWARD' to enable it.

 DUMMYNET is entirely handled within the ipfw PFIL handlers.  A packet for
 a dummynet pipe or queue is directly sent to dummynet_io().  Dummynet will
 then inject it back into ip_input/ip_output() after it has served its time.
 Dummynet packets are tagged and will continue from the next rule when they
 hit the ipfw PFIL handlers again after re-injection.

 BRIDGING and IPFW_ETHER are not changed yet and use ipfw_chk() directly as
 they did before.  Later this will be changed to dedicated ETHER PFIL_HOOKS.

More detailed changes to the code:

 conf/files
	Add netinet/ip_fw_pfil.c.

 conf/options
	Add IPFIREWALL_FORWARD option.

 modules/ipfw/Makefile
	Add ip_fw_pfil.c.

 net/bridge.c
	Disable PFIL_HOOKS if ipfw for bridging is active.  Bridging ipfw
	is still directly invoked to handle layer2 headers and packets would
	get a double ipfw when run through PFIL_HOOKS as well.

 netinet/ip_divert.c
	Removed divert_clone() function.  It is no longer used.

 netinet/ip_dummynet.[ch]
	Neither the route 'ro' nor the destination 'dst' need to be stored
	while in dummynet transit.  Structure members and associated macros
	are removed.

 netinet/ip_fastfwd.c
	Removed all direct ipfw handling code and replace it with the new
	'ipfw forward' handling code.

 netinet/ip_fw.h
	Removed 'ro' and 'dst' from struct ip_fw_args.

 netinet/ip_fw2.c
	(Re)moved some global variables and the module handling.

 netinet/ip_fw_pfil.c
	New file containing the ipfw PFIL handlers and module initialization.

 netinet/ip_input.c
	Removed all direct ipfw handling code and replace it with the new
	'ipfw forward' handling code.  ip_forward() does not longer require
	the 'next_hop' struct sockaddr_in argument.  Disable early checks
	if 'srcrt' is set.

 netinet/ip_output.c
	Removed all direct ipfw handling code and replace it with the new
	'ipfw forward' handling code.

 netinet/ip_var.h
	Add ip_reass() as general function.  (Used from ipfw PFIL handlers
	for IPDIVERT.)

 netinet/raw_ip.c
	Directly check if ipfw and dummynet control pointers are active.

 netinet/tcp_input.c
	Rework the 'ipfw forward' to local code to work with the new way of
	forward tags.

 netinet/tcp_sack.c
	Remove include 'opt_ipfw.h' which is not needed here.

 sys/mbuf.h
	Remove m_claim_next() macro which was exclusively for ipfw 'forward'
	and is no longer needed.

Approved by:	re (scottl)
2004-08-17 22:05:54 +00:00
David Malone
1f44b0a1b5 Get rid of the RANDOM_IP_ID option and make it a sysctl. NetBSD
have already done this, so I have styled the patch on their work:

        1) introduce a ip_newid() static inline function that checks
        the sysctl and then decides if it should return a sequential
        or random IP ID.

        2) named the sysctl net.inet.ip.random_id

        3) IPv6 flow IDs and fragment IDs are now always random.
        Flow IDs and frag IDs are significantly less common in the
        IPv6 world (ie. rarely generated per-packet), so there should
        be smaller performance concerns.

The sysctl defaults to 0 (sequential IP IDs).

Reviewed by:	andre, silby, mlaier, ume
Based on:	NetBSD
MFC after:	2 months
2004-08-14 15:32:40 +00:00
Andre Oppermann
2bde81acd6 Provide the sysctl net.inet.ip.process_options to control the processing
of IP options.

 net.inet.ip.process_options=0  Ignore IP options and pass packets unmodified.
 net.inet.ip.process_options=1  Process all IP options (default).
 net.inet.ip.process_options=2  Reject all packets with IP options with ICMP
  filter prohibited message.

This sysctl affects packets destined for the local host as well as those
only transiting through the host (routing).

IP options do not have any legitimate purpose anymore and are only used
to circumvent firewalls or to exploit certain behaviours or bugs in TCP/IP
stacks.

Reviewed by:	sam (mentor)
2004-05-06 18:46:03 +00:00
Darren Reed
ab884d993e Rename ip_claim_next_hop() to m_claim_next_hop(), give it an extra arg
(the type of tag to claim) and push it out of ip_var.h into mbuf.h alongside
all of the other macros that work ok mbuf's and tag's.
2004-05-02 06:36:30 +00:00
Warner Losh
f36cfd49ad Remove advertising clause from University of California Regent's
license, per letter dated July 22, 1999 and email from Peter Wemm,
Alan Cox and Robert Watson.

Approved by: core, peter, alc, rwatson
2004-04-07 20:46:16 +00:00
Max Laier
ac9d7e2618 Re-remove MT_TAGs. The problems with dummynet have been fixed now.
Tested by: -current, bms(mentor), me
Approved by: bms(mentor), sam
2004-02-25 19:55:29 +00:00
Max Laier
36e8826ffb Backout MT_TAG removal (i.e. bring back MT_TAGs) for now, as dummynet is
not working properly with the patch in place.

Approved by: bms(mentor)
2004-02-18 00:04:52 +00:00
Max Laier
1094bdca51 This set of changes eliminates the use of MT_TAG "pseudo mbufs", replacing
them mostly with packet tags (one case is handled by using an mbuf flag
since the linkage between "caller" and "callee" is direct and there's no
need to incur the overhead of a packet tag).

This is (mostly) work from: sam

Silence from: -arch
Approved by: bms(mentor), sam, rwatson
2004-02-13 19:14:16 +00:00
Andre Oppermann
c76ff7084f Make ipstealth global as we need it in ip_fastforward too. 2003-11-15 01:45:56 +00:00
Andre Oppermann
02c1c7070e Remove the global one-level rtcache variable and associated
complex locking and rework ip_rtaddr() to do its own rtlookup.
Adopt all its callers to this and make ip_output() callable
with NULL rt pointer.

Reviewed by:	sam (mentor)
2003-11-14 21:48:57 +00:00
Robert Watson
eca8a663d4 Modify the MAC Framework so that instead of embedding a (struct label)
in various kernel objects to represent security data, we embed a
(struct label *) pointer, which now references labels allocated using
a UMA zone (mac_label.c).  This allows the size and shape of struct
label to be varied without changing the size and shape of these kernel
objects, which become part of the frozen ABI with 5-STABLE.  This opens
the door for boot-time selection of the number of label slots, and hence
changes to the bound on the number of simultaneous labeled policies
at boot-time instead of compile-time.  This also makes it easier to
embed label references in new objects as required for locking/caching
with fine-grained network stack locking, such as inpcb structures.

This change also moves us further in the direction of hiding the
structure of kernel objects from MAC policy modules, not to mention
dramatically reducing the number of '&' symbols appearing in both the
MAC Framework and MAC policy modules, and improving readability.

While this results in minimal performance change with MAC enabled, it
will observably shrink the size of a number of critical kernel data
structures for the !MAC case, and should have a small (but measurable)
performance benefit (i.e., struct vnode, struct socket) do to memory
conservation and reduced cost of zeroing memory.

NOTE: Users of MAC must recompile their kernel and all MAC modules as a
result of this change.  Because this is an API change, third party
MAC modules will also need to be updated to make less use of the '&'
symbol.

Suggestions from:	bmilekic
Obtained from:		TrustedBSD Project
Sponsored by:		DARPA, Network Associates Laboratories
2003-11-12 03:14:31 +00:00
Sam Leffler
252f24a2cf divert socket fixups:
o pickup Giant in divert_packet to protect sbappendaddr since it
  can be entered through MPSAFE callouts or through ip_input when
  mpsafenet is 1
o add missing locking on output
o add locking to abort and shutdown
o add a ctlinput handler to invalidate held routing table references
  on an ICMP redirect (may not be needed)

Supported by:	FreeBSD Foundation
2003-11-08 23:09:42 +00:00
Sam Leffler
929b31ddab Lock ip forwarding route cache. While we're at it, remove the global
variable ipforward_rt by introducing an ip_forward_cacheinval() call
to use to invalidate the cache.

Supported by:	FreeBSD Foundation
2003-10-14 19:19:12 +00:00
Sam Leffler
134ea22494 o update PFIL_HOOKS support to current API used by netbsd
o revamp IPv4+IPv6+bridge usage to match API changes
o remove pfil_head instances from protosw entries (no longer used)
o add locking
o bump FreeBSD version for 3rd party modules

Heavy lifting by:	"Max Laier" <max@love2party.net>
Supported by:		FreeBSD Foundation
Obtained from:		NetBSD (bits of pfil.h and pfil.c)
2003-09-23 17:54:04 +00:00
Bruce M Simpson
8afa230470 Add the IP_ONESBCAST option, to enable undirected IP broadcasts to be sent on
specific interfaces. This is required by aodvd, and may in future help us
in getting rid of the requirement for BPF from our import of isc-dhcp.

Suggested by:   fenestro
Obtained from:  BSD/OS
Reviewed by:    mini, sam
Approved by:    jake (mentor)
2003-08-20 14:46:40 +00:00
Jeffrey Hsu
1e78ac216e 1. Basic PIM kernel support
Disabled by default. To enable it, the new "options PIM" must be
added to the kernel configuration file (in addition to MROUTING):

options	MROUTING		# Multicast routing
options	PIM			# Protocol Independent Multicast

2. Add support for advanced multicast API setup/configuration and
extensibility.

3. Add support for kernel-level PIM Register encapsulation.
Disabled by default.  Can be enabled by the advanced multicast API.

4. Implement a mechanism for "multicast bandwidth monitoring and upcalls".

Submitted by:	Pavlin Radoslavov <pavlin@icir.org>
2003-08-07 18:16:59 +00:00
Matthew N. Dodd
2c56e246fa Back out support for RFC3514.
RFC3514 poses an unacceptale risk to compliant systems.
2003-04-02 20:14:44 +00:00
Matthew N. Dodd
09139a4537 Implement support for RFC 3514 (The Security Flag in the IPv4 Header).
(See: ftp://ftp.rfc-editor.org/in-notes/rfc3514.txt)

This fulfills the host requirements for userland support by
way of the setsockopt() IP_EVIL_INTENT message.

There are three sysctl tunables provided to govern system behavior.

	net.inet.ip.rfc3514:

		Enables support for rfc3514.  As this is an
		Informational RFC and support is not yet widespread
		this option is disabled by default.

	net.inet.ip.hear_no_evil

		 If set the host will discard all received evil packets.

	net.inet.ip.speak_no_evil

		If set the host will discard all transmitted evil packets.

The IP statistics counter 'ips_evil' (available via 'netstat') provides
information on the number of 'evil' packets recieved.

For reference, the '-E' option to 'ping' has been provided to demonstrate
and test the implementation.
2003-04-01 08:21:44 +00:00
Mike Silbersack
375386e284 Add the ability to limit the number of IP fragments allowed per packet,
and enable it by default, with a limit of 16.

At the same time, tweak maxfragpackets downward so that in the worst
possible case, IP reassembly can use only 1/2 of all mbuf clusters.

MFC after: 	3 days
Reviewed by:	hsu
Liked by:	bmah
2003-02-22 06:41:47 +00:00
Luigi Rizzo
b375c9ec2c Back out the ip_fragment() code -- it is not urgent to have it in now,
I will put it back in in a better form after 5.0 is out.

Requested by: sam, rwatson, luigi (on second thought)
Approved by: re
2002-11-20 18:56:25 +00:00
Luigi Rizzo
3e372e140c Move the ip_fragment code from ip_output() to a separate function,
so that it can be reused elsewhere (there is a number of places
where it can be useful). This also trims some 200 lines from
the body of ip_output(), which helps readability a bit.

(This change was discussed a few weeks ago on the mailing lists,
Julian agreed, silence from others. It is not a functional change,
so i expect it to be ok to commit it now but i am happy to back it
out if there are objections).

While at it, fix some function headers and replace m_copy() with
m_copypacket() where applicable.

MFC after: 1 week
2002-11-17 16:30:44 +00:00
Luigi Rizzo
bbb4330b61 Massive cleanup of the ip_mroute code.
No functional changes, but:

  + the mrouting module now should behave the same as the compiled-in
    version (it did not before, some of the rsvp code was not loaded
    properly);
  + netinet/ip_mroute.c is now truly optional;
  + removed some redundant/unused code;
  + changed many instances of '0' to NULL and INADDR_ANY as appropriate;
  + removed several static variables to make the code more SMP-friendly;
  + fixed some minor bugs in the mrouting code (mostly, incorrect return
    values from functions).

This commit is also a prerequisite to the addition of support for PIM,
which i would like to put in before DP2 (it does not change any of
the existing APIs, anyways).

Note, in the process we found out that some device drivers fail to
properly handle changes in IFF_ALLMULTI, leading to interesting
behaviour when a multicast router is started. This bug is not
corrected by this commit, and will be fixed with a separate commit.

Detailed changes:
--------------------
netinet/ip_mroute.c     all the above.
conf/files              make ip_mroute.c optional
net/route.c             fix mrt_ioctl hook
netinet/ip_input.c      fix ip_mforward hook, move rsvp_input() here
                        together with other rsvp code, and a couple
                        of indentation fixes.
netinet/ip_output.c     fix ip_mforward and ip_mcast_src hooks
netinet/ip_var.h        rsvp function hooks
netinet/raw_ip.c        hooks for mrouting and rsvp functions, plus
                        interface cleanup.
netinet/ip_mroute.h     remove an unused and optional field from a struct

Most of the code is from Pavlin Radoslavov and the XORP project

Reviewed by: sam
MFC after: 1 week
2002-11-15 22:53:53 +00:00
Poul-Henning Kamp
53be11f680 Fix two instances of variant struct definitions in sys/netinet:
Remove the never completed _IP_VHL version, it has not caught on
anywhere and it would make us incompatible with other BSD netstacks
to retain this version.

Add a CTASSERT protecting sizeof(struct ip) == 20.

Don't let the size of struct ipq depend on the IPDIVERT option.

This is a functional no-op commit.

Approved by:	re
2002-10-20 22:52:07 +00:00
Sam Leffler
5d84645305 Replace aux mbufs with packet tags:
o instead of a list of mbufs use a list of m_tag structures a la openbsd
o for netgraph et. al. extend the stock openbsd m_tag to include a 32-bit
  ABI/module number cookie
o for openbsd compatibility define a well-known cookie MTAG_ABI_COMPAT and
  use this in defining openbsd-compatible m_tag_find and m_tag_get routines
o rewrite KAME use of aux mbufs in terms of packet tags
o eliminate the most heavily used aux mbufs by adding an additional struct
  inpcb parameter to ip_output and ip6_output to allow the IPsec code to
  locate the security policy to apply to outbound packets
o bump __FreeBSD_version so code can be conditionalized
o fixup ipfilter's call to ip_output based on __FreeBSD_version

Reviewed by:	julian, luigi (silent), -arch, -net, darren
Approved by:	julian, silence from everyone else
Obtained from:	openbsd (mostly)
MFC after:	1 month
2002-10-16 01:54:46 +00:00
Robert Watson
9daf40feaa Perform a nested include of _label.h if #ifdef _KERNEL. This will
satisfy consumers of ip_var.h that need a complete definition of
struct ipq and don't include mac.h.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, NAI Labs
2002-08-15 14:34:02 +00:00
Robert Watson
549e4c9e4e Introduce support for Mandatory Access Control and extensible
kernel access control.

Label IP fragment reassembly queues, permitting security features to
be maintained on those objects.  ipq_label will be used to manage
the reassembly of fragments into IP datagrams using security
properties.  This permits policies to deny the reassembly of fragments,
as well as influence the resulting label of a datagram following
reassembly.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, NAI Labs
2002-07-30 23:09:20 +00:00
Robert Watson
69dac2ea47 Don't export 'struct ipq' from kernel, instead #ifdef _KERNEL. As kernel
data structures pick up security and synchronization primitives, it
becomes increasingly desirable not to arbitrarily export them via
include files to userland, as the userland applications pick up new
#include dependencies.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, NAI Labs
2002-07-20 22:46:20 +00:00
Luigi Rizzo
ec3057db9e Remove ip_fw_fwd_addr (forgotten in previous commit)
remove some extra whitespace.
2002-06-23 09:03:42 +00:00
Luigi Rizzo
2b25acc158 Remove (almost all) global variables that were used to hold
packet forwarding state ("annotations") during ip processing.
The code is considerably cleaner now.

The variables removed by this change are:

        ip_divert_cookie        used by divert sockets
        ip_fw_fwd_addr          used for transparent ip redirection
        last_pkt                used by dynamic pipes in dummynet

Removal of the first two has been done by carrying the annotations
into volatile structs prepended to the mbuf chains, and adding
appropriate code to add/remove annotations in the routines which
make use of them, i.e. ip_input(), ip_output(), tcp_input(),
bdg_forward(), ether_demux(), ether_output_frame(), div_output().

On passing, remove a bug in divert handling of fragmented packet.
Now it is the fragment at offset 0 which sets the divert status of
the whole packet, whereas formerly it was the last incoming fragment
to decide.

Removal of last_pkt required a change in the interface of ip_fw_chk()
and dummynet_io(). On passing, use the same mechanism for dummynet
annotations and for divert/forward annotations.

option IPFIREWALL_FORWARD is effectively useless, the code to
implement it is very small and is now in by default to avoid the
obfuscation of conditionally compiled code.

NOTES:
 * there is at least one global variable left, sro_fwd, in ip_output().
   I am not sure if/how this can be removed.

 * I have deliberately avoided gratuitous style changes in this commit
   to avoid cluttering the diffs. Minor stule cleanup will likely be
   necessary

 * this commit only focused on the IP layer. I am sure there is a
   number of global variables used in the TCP and maybe UDP stack.

 * despite the number of files touched, there are absolutely no API's
   or data structures changed by this commit (except the interfaces of
   ip_fw_chk() and dummynet_io(), which are internal anyways), so
   an MFC is quite safe and unintrusive (and desirable, given the
   improved readability of the code).

MFC after: 10 days
2002-06-22 11:51:02 +00:00
Alfred Perlstein
4d77a549fe Remove __P. 2002-03-19 21:25:46 +00:00
Ruslan Ermilov
bd7142087b - Make ip_rtaddr() global, and use it to look up the correct source
address in icmp_reflect().
- Two new "struct icmpstat" members: icps_badaddr and icps_noroute.

PR:		kern/31575
Obtained from:	BSD/OS
MFC after:	1 week
2001-11-30 10:40:28 +00:00
Julian Elischer
f0ffb944d2 Patches from Keiichi SHIMA <keiichi@iij.ad.jp>
to make ip use the standard protosw structure again.

Obtained from: Well, KAME I guess.
2001-09-03 20:03:55 +00:00
Hajimu UMEMOTO
3384154590 Sync with recent KAME.
This work was based on kame-20010528-freebsd43-snap.tgz and some
critical problem after the snap was out were fixed.
There are many many changes since last KAME merge.

TODO:
  - The definitions of SADB_* in sys/net/pfkeyv2.h are still different
    from RFC2407/IANA assignment because of binary compatibility
    issue.  It should be fixed under 5-CURRENT.
  - ip6po_m member of struct ip6_pktopts is no longer used.  But, it
    is still there because of binary compatibility issue.  It should
    be removed under 5-CURRENT.

Reviewed by:	itojun
Obtained from:	KAME
MFC after:	3 weeks
2001-06-11 12:39:29 +00:00
Kris Kennaway
64dddc1872 Add ``options RANDOM_IP_ID'' which randomizes the ID field of IP packets.
This closes a minor information leak which allows a remote observer to
determine the rate at which the machine is generating packets, since the
default behaviour is to increment a counter for each packet sent.

Reviewed by:    -net
Obtained from:  OpenBSD
2001-06-01 10:02:28 +00:00
Ruslan Ermilov
1e3d5af041 Invalidate cached forwarding route (ipforward_rt) whenever a new route
is added to the routing table, otherwise we may end up using the wrong
route when forwarding.

PR:		kern/10778
Reviewed by:	silence on -net
2001-03-19 09:16:16 +00:00
Poul-Henning Kamp
462b86fe91 <sys/queue.h> makeover. 2001-03-16 20:00:53 +00:00