Commit Graph

137 Commits

Author SHA1 Message Date
luigi
b13eda2674 fix a typo in a comment 2015-07-18 15:28:32 +00:00
glebius
7c22152af0 o Use new function ip_fillid() in all places throughout the kernel,
where we want to create a new IP datagram.
o Add support for RFC6864, which allows to set IP ID for atomic IP
  datagrams to any value, to improve performance. The behaviour is
  controlled by net.inet.ip.rfc6864 sysctl knob, which is enabled by
  default.
o In case if we generate IP ID, use counter(9) to improve performance.
o Gather all code related to IP ID into ip_id.c.

Differential Revision:		https://reviews.freebsd.org/D2177
Reviewed by:			adrian, cy, rpaulo
Tested by:			Emeric POUPON <emeric.poupon stormshield.eu>
Sponsored by:			Netflix
Sponsored by:			Nginx, Inc.
Relnotes:			yes
2015-04-01 22:26:39 +00:00
fabient
d819d79785 On multi CPU systems, we may emit successive packets with the same id.
Fix the race by using an atomic operation.

Differential Revision:	https://reviews.freebsd.org/D2141
Obtained from:	emeric.poupon@stormshield.eu
MFC after:	1 week
Sponsored by:	Stormshield
2015-03-27 13:26:59 +00:00
adrian
aab402c146 Add a flag to ip_output() - IP_NODEFAULTFLOWID - which prevents it from
overriding an existing flowid/flowtype field in the outbound mbuf with
the inp_flowid/inp_flowtype details.

The upcoming RSS UDP support calculates a valid RSS value for outbound
mbufs and since it may change per send, it doesn't cache it in the inpcb.
So overriding it here would be wrong.

Differential Revision:	https://reviews.freebsd.org/D527
Reviewed by:	grehan
2014-09-09 00:19:02 +00:00
kevlo
dd40fa7e62 Change pr_output's prototype to avoid the need for explicit casts.
This is a follow up to r269699.

Phabric:	D564
Reviewed by:	jhb
2014-08-15 02:43:02 +00:00
kevlo
7727a3c215 Merge 'struct ip6protosw' and 'struct protosw' into one. Now we have
only one protocol switch structure that is shared between ipv4 and ipv6.

Phabric:	D476
Reviewed by:	jhb
2014-08-08 01:57:15 +00:00
glebius
d734bed796 Since both netinet/ and netinet6/ call into netipsec/ and netpfil/,
the protocol specific mbuf flags are shared between them.

- Move all M_FOO definitions into a single place: netinet/in6.h, to
  avoid future  clashes.
- Resolve clash between M_DECRYPTED and M_SKIP_FIREWALL which resulted
  in a failure of operation of IPSEC and packet filters.

Thanks to Nicolas and Georgios for all the hard work on bisecting,
testing and finally finding the root of the problem.

PR:			kern/186755
PR:			kern/185876
In collaboration with:	Georgios Amanakis <gamanakis gmail.com>
In collaboration with:	Nicolas DEFFAYET <nicolas-ml deffayet.com>
Sponsored by:		Nginx, Inc.
2014-03-12 14:29:08 +00:00
andre
fd76db4587 Move the global M_SKIP_FIREWALL mbuf flags to a protocol layer specific
flag instead.  The flag is only used within the IP and IPv6 layer 3
protocols.

Because some firewall packages treat IPv4 and IPv6 packets the same the
flag should have the same value for both.

Discussed with:	trociny, glebius
2013-08-19 11:08:36 +00:00
andre
1b3e4b45e5 Move ip_reassemble()'s use of the global M_FRAG mbuf flag to a protocol layer
specific flag instead.  The flag is only relevant while the packet stays in
the IP reassembly queue.

Discussed with:	trociny, glebius
2013-08-19 10:34:10 +00:00
ae
1b1e1de2b2 Use new macros to implement ipstat and tcpstat using PCPU counters.
Change interface of kread_counters() similar ot kread() in the netstat(1).
2013-07-09 09:43:03 +00:00
ae
d657004b7f Reflect removing of the counter_u64_subtract() function in the macro. 2013-04-12 16:29:15 +00:00
glebius
2a0fbb38ed Merge from projects/counters: TCP/IP stats.
Convert 'struct ipstat' and 'struct tcpstat' to counter(9).

  This speeds up IP forwarding at extreme packet rates, and
makes accounting more precise.

Sponsored by:	Nginx, Inc.
2013-04-08 19:57:21 +00:00
ae
4354018055 Remove the recently added sysctl variable net.pfil.forward.
Instead, add protocol specific mbuf flags M_IP_NEXTHOP and
M_IP6_NEXTHOP. Use them to indicate that the mbuf's chain
contains the PACKET_TAG_IPFORWARD tag. And do a tag lookup
only when this flag is set.

Suggested by:	andre
2012-11-02 01:20:55 +00:00
glebius
f79061ff05 o Remove last argument to ip_fragment(), and obtain all needed information
on checksums directly from mbuf flags. This simplifies code.
o Clear CSUM_IP from the mbuf in ip_fragment() if we did checksums in
  hardware. Some driver may not announce CSUM_IP in theur if_hwassist,
  although try to do checksums if CSUM_IP set on mbuf. Example is em(4).
o While here, consistently use CSUM_IP instead of its alias CSUM_DELAY_IP.
  After this change CSUM_DELAY_IP vanishes from the stack.

Submitted by:	Sebastian Kuzminsky <seb lineratesystems.com>
2012-10-26 21:06:33 +00:00
melifaro
02e40e1b73 Do not check if found IPv4 rte is dynamic if net.inet.icmp.drop_redirect is
enabled. This eliminates one mtx_lock() per each routing lookup thus improving
performance in several cases (routing to directly connected interface or routing
to default gateway).

Icmp redirects should not be used to provide routing direction nowadays, even
for end hosts. Routers should not use them too (and this is explicitly restricted
in IPv6, see RFC 4861, clause 8.2).

Current commit changes rnh_machaddr function to 'stock' rn_match (and back) for every
AF_INET routing table in given VNET instance on drop_redirect sysctl change.

This change is part of bigger patch eliminating rte locking.

Sponsored by:	Yandex LLC
MFC after:	2 weeks
2012-10-10 19:06:11 +00:00
melifaro
1fbae66b6e Introduce new link-layer PFIL hook V_link_pfil_hook.
Merge ether_ipfw_chk() and part of bridge_pfil() into
unified ipfw_check_frame() function called by PFIL.
This change was suggested by rwatson? @ DevSummit.

Remove ipfw headers from ether/bridge code since they are unneeded now.

Note this thange introduce some (temporary) performance penalty since
PFIL read lock has to be acquired for every link-level packet.

MFC after:     3 weeks
2012-09-04 19:43:26 +00:00
jhb
419867b9b4 Defer the work of freeing IPv4 multicast options from a socket to an
asychronous task.  This avoids tearing down multicast state including
sending IGMP leave messages and reprogramming MAC filters while holding
the per-protocol global pcbinfo lock that is used in the receive path of
packet processing.

Reviewed by:	rwatson
MFC after:	1 month
2011-12-29 20:41:16 +00:00
ae
6b5f802b89 Add new rule actions "call" and "return" to ipfw. They make
possible to organize subroutines with rules.

The "call" action saves the current rule number in the internal
stack and rules processing continues from the first rule with
specified number (similar to skipto action). If later a rule with
"return" action is encountered, the processing returns to the first
rule with number of "call" rule saved in the stack plus one or higher.

Submitted by:	Vadim Goncharov
Discussed by:	ipfw@, luigi@
2011-06-29 10:06:58 +00:00
bz
25cccaf492 MFp4 CH=191470:
Move the ipport_tick_callout and related functions from ip_input.c
to in_pcb.c.  The random source port allocation code has been merged
and is now local to in_pcb.c only.
Use a SYSINIT to get the callout started and no longer depend on
initialization from the inet code, which would not work in an IPv6
only setup.

Reviewed by:	gnn
Sponsored by:	The FreeBSD Foundation
Sponsored by:	iXsystems
MFC after:	4 days
2011-04-20 08:00:29 +00:00
bz
18b40a43ee MFp4 CH=183052 183053 183258:
In protosw we define pr_protocol as short, while on the wire
  it is an uint8_t.  That way we can have "internal" protocols
  like DIVERT, SEND or gaps for modules (PROTO_SPACER).
  Switch ipproto_{un,}register to accept a short protocol number(*)
  and do an upfront check for valid boundries. With this we
  also consistently report EPROTONOSUPPORT for out of bounds
  protocols, as we did for proto == 0.  This allows a caller
  to not error for this case, which is especially important
  if we want to automatically call these from domain handling.

  (*) the functions have been without any in-tree consumer
  since the initial introducation, so this is considered save.

  Implement ip6proto_{un,}register() similarly to their legacy IP
  counter parts to allow modules to hook up dynamically.

Reviewed by:	philip, will
MFC after:	1 week
2010-09-02 17:43:44 +00:00
bz
0a90ef1728 MFP4: @176978-176982, 176984, 176990-176994, 177441
"Whitspace" churn after the VIMAGE/VNET whirls.

Remove the need for some "init" functions within the network
stack, like pim6_init(), icmp_init() or significantly shorten
others like ip6_init() and nd6_init(), using static initialization
again where possible and formerly missed.

Move (most) variables back to the place they used to be before the
container structs and VIMAGE_GLOABLS (before r185088) and try to
reduce the diff to stable/7 and earlier as good as possible,
to help out-of-tree consumers to update from 6.x or 7.x to 8 or 9.

This also removes some header file pollution for putatively
static global variables.

Revert VIMAGE specific changes in ipfilter::ip_auth.c, that are
no longer needed.

Reviewed by:	jhb
Discussed with:	rwatson
Sponsored by:	The FreeBSD Foundation
Sponsored by:	CK Software GmbH
MFC after:	6 days
2010-04-29 11:52:42 +00:00
bz
29381991cf Split up ip_drain() into an outer lock and iterator part and
a "locked" version that will only handle a single network stack
instance. The latter is called directly from ip_destroy().

Hook up an ip_destroy() function to release resources from the
legacy IP network layer upon virtual network stack teardown.

Sponsored by:	ISPsystem
Reviewed by:	rwatson
MFC After:	5 days
2010-02-20 19:59:52 +00:00
luigi
db333db4e6 Following up on a request from Ermal Luci to make
ip_divert work as a client of pf(4),
make ip_divert not depend on ipfw.

This is achieved by moving to ip_var.h the struct ipfw_rule_ref
(which is part of the mtag for all reinjected packets) and other
declarations of global variables, and moving to raw_ip.c global
variables for filter and divert hooks.

Note that names and locations could be made more generic
(ipfw_rule_ref is really a generic reference robust to reconfigurations;
the packet filter is not necessarily ipfw; filters and their clients
are not necessarily limited to ipv4), but _right now_ most
of this stuff works on ipfw and ipv4, so i don't feel like
doing a gratuitous renaming, at least for the time being.
2010-01-07 10:39:15 +00:00
julian
79c1f884ef Virtualize the pfil hooks so that different jails may chose different
packet filters. ALso allows ipfw to be enabled on on ejail and disabled
on another. In 8.0 it's a global setting.

Sitting aroung in tree waiting to commit for: 2 months
MFC after:	2 months
2009-10-11 05:59:43 +00:00
rwatson
5c6699ad3d Many network stack subsystems use a single global data structure to hold
all pertinent statatistics for the subsystem.  These structures are
sometimes "borrowed" by kernel modules that require a place to store
statistics for similar events.

Add KPI accessor functions for statistics structures referenced by kernel
modules so that they no longer encode certain specifics of how the data
structures are named and stored.  This change is intended to make it
easier to move to per-CPU network stats following 8.0-RELEASE.

The following modules are affected by this change:

      if_bridge
      if_cxgb
      if_gif
      ip_mroute
      ipdivert
      pf

In practice, most of these statistics consumers should, in fact, maintain
their own statistics data structures rather than borrowing structures
from the base network stack.  However, that change is too agressive for
this point in the release cycle.

Reviewed by:	bz
Approved by:	re (kib)
2009-08-02 19:43:32 +00:00
rwatson
88f8de4d40 Remove unused VNET_SET() and related macros; only VNET_GET() is
ever actually used.  Rename VNET_GET() to VNET() to shorten
variable references.

Discussed with:	bz, julian
Reviewed by:	bz
Approved by:	re (kensmith, kib)
2009-07-16 21:13:04 +00:00
rwatson
57ca4583e7 Build on Jeff Roberson's linker-set based dynamic per-CPU allocator
(DPCPU), as suggested by Peter Wemm, and implement a new per-virtual
network stack memory allocator.  Modify vnet to use the allocator
instead of monolithic global container structures (vinet, ...).  This
change solves many binary compatibility problems associated with
VIMAGE, and restores ELF symbols for virtualized global variables.

Each virtualized global variable exists as a "reference copy", and also
once per virtual network stack.  Virtualized global variables are
tagged at compile-time, placing the in a special linker set, which is
loaded into a contiguous region of kernel memory.  Virtualized global
variables in the base kernel are linked as normal, but those in modules
are copied and relocated to a reserved portion of the kernel's vnet
region with the help of a the kernel linker.

Virtualized global variables exist in per-vnet memory set up when the
network stack instance is created, and are initialized statically from
the reference copy.  Run-time access occurs via an accessor macro, which
converts from the current vnet and requested symbol to a per-vnet
address.  When "options VIMAGE" is not compiled into the kernel, normal
global ELF symbols will be used instead and indirection is avoided.

This change restores static initialization for network stack global
variables, restores support for non-global symbols and types, eliminates
the need for many subsystem constructors, eliminates large per-subsystem
structures that caused many binary compatibility issues both for
monitoring applications (netstat) and kernel modules, removes the
per-function INIT_VNET_*() macros throughout the stack, eliminates the
need for vnet_symmap ksym(2) munging, and eliminates duplicate
definitions of virtualized globals under VIMAGE_GLOBALS.

Bump __FreeBSD_version and update UPDATING.

Portions submitted by:  bz
Reviewed by:            bz, zec
Discussed with:         gnn, jamie, jeff, jhb, julian, sam
Suggested by:           peter
Approved by:            re (kensmith)
2009-07-14 22:48:30 +00:00
bz
b017972f11 Add the explicit include of vimage.h to another five .c files still
missing it.

Remove the "hidden" kernel only include of vimage.h from ip_var.h added
with the very first Vimage commit r181803 to avoid further kernel poisoning.
2009-06-17 12:44:11 +00:00
zec
8b1f38241a Introduce an infrastructure for dismantling vnet instances.
Vnet modules and protocol domains may now register destructor
functions to clean up and release per-module state.  The destructor
mechanisms can be triggered by invoking "vimage -d", or a future
equivalent command which will be provided via the new jail framework.

While this patch introduces numerous placeholder destructor functions,
many of those are currently incomplete, thus leaking memory or (even
worse) failing to stop all running timers.  Many of such issues are
already known and will be incrementaly fixed over the next weeks in
smaller incremental commits.

Apart from introducing new fields in structs ifnet, domain, protosw
and vnet_net, which requires the kernel and modules to be rebuilt, this
change should have no impact on nooptions VIMAGE builds, since vnet
destructors can only be called in VIMAGE kernels.  Moreover,
destructor functions should be in general compiled in only in
options VIMAGE builds, except for kernel modules which can be safely
kldunloaded at run time.

Bump __FreeBSD_version to 800097.
Reviewed by:	bz, julian
Approved by:	rwatson, kib (re), julian (mentor)
2009-06-08 17:15:40 +00:00
luigi
1384b62c4b More cleanup in preparation of ipfw relocation (no actual code change):
+ move ipfw and dummynet hooks declarations to raw_ip.c (definitions
  in ip_var.h) same as for most other global variables.
  This removes some dependencies from ip_input.c;

+ remove the IPFW_LOADED macro, just test ip_fw_chk_ptr directly;

+ remove the DUMMYNET_LOADED macro, just test ip_dn_io_ptr directly;

+ move ip_dn_ruledel_ptr to ip_fw2.c which is the only file using it;

To be merged together with rev 193497

MFC after:	5 days
2009-06-05 13:44:30 +00:00
rwatson
692f8aa2fa Update stats in struct ipstat using four new macros, IPSTAT_ADD(),
IPSTAT_INC(), IPSTAT_SUB(), and IPSTAT_DEC(), rather than directly
manipulating the fields across the kernel.  This will make it easier
to change the implementation of these statistics, such as using
per-CPU versions of the data structures.

MFC after:	3 days
2009-04-11 23:35:20 +00:00
bms
71233409ea Merge IGMPv3 and Source-Specific Multicast (SSM) to the FreeBSD
IPv4 stack.

Diffs are minimized against p4.
PCS has been used for some protocol verification, more widespread
testing of recorded sources in Group-and-Source queries is needed.
sizeof(struct igmpstat) has changed.

__FreeBSD_version is bumped to 800070.
2009-03-09 17:53:05 +00:00
bz
83a32f8750 Put a global variables, which were virtualized but formerly
missed under VIMAGE_GLOBAL.

Start putting the extern declarations of the  virtualized globals
under VIMAGE_GLOBAL as the globals themsevles are already.
This will help by the time when we are going to remove the globals
entirely.

While there garbage collect a few dead externs from ip6_var.h.

Sponsored by:	The FreeBSD Foundation
2008-12-11 16:26:38 +00:00
zec
7b573d1496 Conditionally compile out V_ globals while instantiating the appropriate
container structures, depending on VIMAGE_GLOBALS compile time option.

Make VIMAGE_GLOBALS a new compile-time option, which by default will not
be defined, resulting in instatiations of global variables selected for
V_irtualization (enclosed in #ifdef VIMAGE_GLOBALS blocks) to be
effectively compiled out.  Instantiate new global container structures
to hold V_irtualized variables: vnet_net_0, vnet_inet_0, vnet_inet6_0,
vnet_ipsec_0, vnet_netgraph_0, and vnet_gif_0.

Update the VSYM() macro so that depending on VIMAGE_GLOBALS the V_
macros resolve either to the original globals, or to fields inside
container structures, i.e. effectively

#ifdef VIMAGE_GLOBALS
#define V_rt_tables rt_tables
#else
#define V_rt_tables vnet_net_0._rt_tables
#endif

Update SYSCTL_V_*() macros to operate either on globals or on fields
inside container structs.

Extend the internal kldsym() lookups with the ability to resolve
selected fields inside the virtualization container structs.  This
applies only to the fields which are explicitly registered for kldsym()
visibility via VNET_MOD_DECLARE() and vnet_mod_register(), currently
this is done only in sys/net/if.c.

Fix a few broken instances of MODULE_GLOBAL() macro use in SCTP code,
and modify the MODULE_GLOBAL() macro to resolve to V_ macros, which in
turn result in proper code being generated depending on VIMAGE_GLOBALS.

De-virtualize local static variables in sys/contrib/pf/net/pf_subr.c
which were prematurely V_irtualized by automated V_ prepending scripts
during earlier merging steps.  PF virtualization will be done
separately, most probably after next PF import.

Convert a few variable initializations at instantiation to
initialization in init functions, most notably in ipfw.  Also convert
TUNABLE_INT() initializers for V_ variables to TUNABLE_FETCH_INT() in
initializer functions.

Discussed at:	devsummit Strassburg
Reviewed by:	bz, julian
Approved by:	julian (mentor)
Obtained from:	//depot/projects/vimage-commit2/...
X-MFC after:	never
Sponsored by:	NLnet Foundation, The FreeBSD Foundation
2008-12-10 23:12:39 +00:00
zec
7ecd715d48 Unhide declarations of network stack virtualization structs from
underneath #ifdef VIMAGE blocks.

This change introduces some churn in #include ordering and nesting
throughout the network stack and drivers but is not expected to cause
any additional issues.

In the next step this will allow us to instantiate the virtualization
container structures and switch from using global variables to their
"containerized" counterparts.

Reviewed by:	bz, julian
Approved by:	julian (mentor)
Obtained from:	//depot/projects/vimage-commit2/...
X-MFC after:	never
Sponsored by:	NLnet Foundation, The FreeBSD Foundation
2008-11-28 23:30:51 +00:00
julian
06489a5bf1 Another V_ forgotten 2008-08-25 05:49:16 +00:00
bz
1021d43b56 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
1dfc5c98a4 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
bms
ffd77d9ba5 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
890976965d Some local and style(9) cleanups. 2007-04-04 15:30:31 +00:00
bms
18895e4f42 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
5d67ac3cb1 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
a6a209f2cc 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
thompsa
d7e928629d 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
imp
a50ffc2912 /* -> /*- for license, minor formatting changes 2005-01-07 01:45:51 +00:00
silby
c79cd91efc 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
00d43f4bd8 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
5b67b5c1f3 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
d243747d92 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
e4a34b65ad 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