MFC r345262:
Modify struct nat64_config.

Add second IPv6 prefix to generic config structure and rename another
fields to conform to RFC6877. Now it contains two prefixes and length:
PLAT is provider-side translator that translates N:1 global IPv6 addresses
to global IPv4 addresses. CLAT is customer-side translator (XLAT) that
algorithmically translates 1:1 IPv4 addresses to global IPv6 addresses.
Use PLAT prefix in stateless (nat64stl) and stateful (nat64lsn)
translators.

Modify nat64_extract_ip4() and nat64_embed_ip4() functions to accept
prefix length and use plat_plen to specify prefix length.

Retire net.inet.ip.fw.nat64_allow_private sysctl variable.
Add NAT64_ALLOW_PRIVATE flag and use "allow_private" config option to
configure this ability separately for each NAT64 instance.

Obtained from: Yandex LLC
Sponsored by: Yandex LLC

MFC r342908:
Reduce the size of struct ip_fw_args from 240 to 128 bytes on amd64.
And refactor the code to avoid unneeded initialization to reduce overhead
of per-packet processing.

ipfw(4) can be invoked by pfil(9) framework for each packet several times.
Each call uses on-stack variable of type struct ip_fw_args to keep the
state of ipfw(4) processing. Currently this variable has 240 bytes size
on amd64. Each time ipfw(4) does bzero() on it, and then it initializes
some fields.

glebius@ has reported that they at Netflix discovered, that initialization
of this variable produces significant overhead on packet processing.
After patching I managed to increase performance of packet processing on
simple routing with ipfw(4) firewalling to about 11% from 9.8Mpps up to
11Mpps (Xeon E5-2660 v4@ + Mellanox 100G card).

Introduced new field flags, it is used to keep track of what fields was
initialized. Some fields were moved into the anonymous union, to reduce
the size. They all are mutually exclusive. dummypar field was unused, and
therefore it is removed. The hopstore6 field type was changed from
sockaddr_in6 to a bit smaller struct ip_fw_nh6. And now the size of struct
ip_fw_args is 128 bytes.

ipfw_chk() was modified to properly handle ip_fw_args.flags instead of
rely on checking for NULL pointers.

Obtained from: Yandex LLC
Sponsored by: Yandex LLC
Differential Revision: https://reviews.freebsd.org/D18690

MFC r342909:
Fix the build with INVARIANTS.

MFC r343551:
Fix the bug introduced in r342908, that causes problems with dynamic
handling for protocols without ports numbers.

Since port numbers were uninitialized for protocols like ICMP/ICMPv6,
ipfw_chk() used some non-zero values to create dynamic states, and due
this it failed to match replies with created states.

Reported by: Oliver Hartmann, Boris Lytochkin
Obtained from: Yandex LLC

MFC r345004 (with modification):
Add IP_FW_NAT64 to codes that ipfw_chk() can return.

It will be used by upcoming NAT64 changes. We use separate code
to avoid propogating EACCES error code to user level applications
when NAT64 consumes a packet.

Obtained from: Yandex LLC
Sponsored by: Yandex LLC

MFC r339810: ipfw: implement ngtee/netgraph actions for layer-2 frames.

Kernel part of ipfw does not support and ignores rules other than
"pass", "deny" and dummynet-related for layer-2 (ethernet frames).
Others are processed as "pass".

Make it support ngtee/netgraph rules just like they are supported
for IP packets. For example, this allows us to mirror some frames
selectively to another interface for delivery to remote network analyzer
over RSPAN vlan. Assuming ng_ipfw(4) netgraph node has a hook named "900"
attached to "lower" hook of vlan900's ng_ether(4) node, that would be
as simple as:

ipfw add ngtee 900 ip from any to 8.8.8.8 layer2 out xmit igb0

PR: 213452
Tested-by: Fyodor Ustinov <ufm@ufm.su>

MFC r308237:

Remove the mbuf tag after use (for reinjected packets).

Fixes the packet processing in dummynet l2 rules.

Obtained from: pfSense
Sponsored by: Rubicon Communications, LLC (Netgate)

Stop abusing from struct ifnet presence to determine the packet direction
for dummynet, use the correct argument for that, remove the false coment
about the presence of struct ifnet.

Fixes the input match of dummynet l2 rules.

Obtained from: pfSense
Sponsored by: Rubicon Communications, LLC (Netgate)

Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

use proper types to represent function pointers

Fix `ipfw fwd tablearg'. Use dedicated field nh4 in struct table_value
to obtain IPv4 next hop address in tablearg case.

Add `fwd tablearg' support for IPv6. ipfw(8) uses INADDR_ANY as next hop
address in O_FORWARD_IP opcode for specifying tablearg case. For IPv6 we
still use this opcode, but when packet identified as IPv6 packet, we
obtain next hop address from dedicated field nh6 in struct table_value.

Replace hopstore field in struct ip_fw_args with anonymous union and add
hopstore6 field. Use this field to copy tablearg value for IPv6.

Replace spare1 field in struct table_value with zoneid. Use it to keep
scope zone id for link-local IPv6 addresses. Since spare1 was used
internally, replace spare0 array with two variables spare0 and spare1.

Use getaddrinfo(3)/getnameinfo(3) functions for parsing and formatting
IPv6 addresses in table_value. Use zoneid field in struct table_value
to store sin6_scope_id value.

Since the kernel still uses embedded scope zone id to represent
link-local addresses, convert next_hop6 address into this form before
return from pfil processing. This also fixes in6_localip() check
for link-local addresses.

Differential Revision: https://reviews.freebsd.org/D2015
Obtained from: Yandex LLC
Sponsored by: Yandex LLC

Remove SYSCTL_VNET_* macros, and simply put CTLFLAG_VNET where needed.

Sponsored by: Nginx, Inc.

Set oif only for outgoing packets.

PR: 188543
MFC after: 1 week
Sponsored by: Yandex LLC

Fix breakage in ipfw+VIMAGE after r261590.

PR: kern/187665
Sponsored by: Nginx, Inc.

make ipfw_check_packet() and ipfw_check_frame() public,
so they can be used in the userspace version of ipfw/dummynet
(normally using netmap for the I/O path).

This is the first of a few commits to ease compiling the
ipfw kernel code in userspace.

Mechanically substitute flags from historic mbuf allocator with
malloc(9) flags within sys.

Exceptions:

- sys/contrib not touched
- sys/mbuf.h edited manually

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

Remove the IPFIREWALL_FORWARD kernel option and make possible to turn
on the related functionality in the runtime via the sysctl variable
net.pfil.forward. It is turned off by default.

Sponsored by: Yandex LLC
Discussed with: net@
MFC after: 2 weeks

Switch the entire IPv4 stack to keep the IP packet header
in network byte order. Any host byte order processing is
done in local variables and host byte order values are
never[1] written to a packet.

After this change a packet processed by the stack isn't
modified at all[2] except for TTL.

After this change a network stack hacker doesn't need to
scratch his head trying to figure out what is the byte order
at the given place in the stack.

[1] One exception still remains. The raw sockets convert host
byte order before pass a packet to an application. Probably
this would remain for ages for compatibility.

[2] The ip_input() still subtructs header len from ip->ip_len,
but this is planned to be fixed soon.

Reviewed by: luigi, Maxim Dounin <mdounin mdounin.ru>
Tested by: ray, Olivier Cochard-Labbe <olivier cochard.me>

Catch up with r241245 and do not return packet back in host byte order.

A step in resolving mess with byte ordering for AF_INET. After this change:

- All packets in NETISR_IP queue are in net byte order.
- ip_input() is entered in net byte order and converts packet
to host byte order right _after_ processing pfil(9) hooks.
- ip_output() is entered in host byte order and converts packet
to net byte order right _before_ processing pfil(9) hooks.
- ip_fragment() accepts and emits packet in net byte order.
- ip_forward(), ip_mloopback() use host byte order (untouched actually).
- ip_fastforward() no longer modifies packet at all (except ip_ttl).
- Swapping of byte order there and back removed from the following modules:
pf(4), ipfw(4), enc(4), if_bridge(4).
- Swapping of byte order added to ipfilter(4), based on __FreeBSD_version
- __FreeBSD_version bumped.
- pfil(9) manual page updated.

Reviewed by: ray, luigi, eri, melifaro
Tested by: glebius (LE), ray (BE)

o Create directory sys/netpfil, where all packet filters should
reside, and move there ipfw(4) and pf(4).

o Move most modified parts of pf out of contrib.

Actual movements:

sys/contrib/pf/net/*.c -> sys/netpfil/pf/
sys/contrib/pf/net/*.h -> sys/net/
contrib/pf/pfctl/*.c -> sbin/pfctl
contrib/pf/pfctl/*.h -> sbin/pfctl
contrib/pf/pfctl/pfctl.8 -> sbin/pfctl
contrib/pf/pfctl/*.4 -> share/man/man4
contrib/pf/pfctl/*.5 -> share/man/man5

sys/netinet/ipfw -> sys/netpfil/ipfw

The arguable movement is pf/net/*.h -> sys/net. There are
future plans to refactor pf includes, so I decided not to
break things twice.

Not modified bits of pf left in contrib: authpf, ftp-proxy,
tftp-proxy, pflogd.

The ipfw(4) movement is planned to be merged to stable/9,
to make head and stable match.

Discussed with: bz, luigi

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

Always use the opt_*.h options for ipfw.ko, not just when
compiled into the kernel.
Do not try to build the module in case of no INET support but
keep #error calls for now in case we would compile it into the
kernel.

This should fix an issue where the module would fail to enable
IPv6 support from the rc framework, but also other INET and INET6
parts being silently compiled out without giving a warning in the
module case.

While here garbage collect unneeded opt_*.h includes.
opt_ipdn.h is not used anywhere but we need to leave the DUMMYNET
entry in options for conditional inclusion in kernel so keep the
file with the same name.

Reported by: pluknet
Reviewed by: plunket, jhb
MFC After: 3 days

Unbreak no-ip and no-inet6 module builds with ipfw. For now continue to
build the ip_fw_pfil.c hooks and ipfw even in case of no-ip under the
assumption that the private L2 hook (which hopefully eventually will be a
pfil hook as well) can still be useful.

Allow building the module without inet as well.

Glanced at by: jhb
MFC after: 3 days

Allow the ipfw.ko module built with a kernel to honor any IPFIREWALL_*
options defined in the kernel config. This more closely matches the
behavior of other modules which inherit configuration settings from the
kernel configuration during a kernel + modules build.

Reviewed by: luigi
Approved by: re (kib)
MFC after: 1 week

Add support for IPv6 to ipfw fwd:
Distinguish IPv4 and IPv6 addresses and optional port numbers in
user space to set the option for the correct protocol family.
Add support in the kernel for carrying the new IPv6 destination
address and port.
Add support to TCP and UDP for IPv6 and fix UDP IPv4 to not change
the address in the IP header.
Add support for IPv6 forwarding to a non-local destination.
Add a regession test uitilizing VIMAGE to check all 20 possible
combinations I could think of.

Obtained from: David Dolson at Sandvine Incorporated
(original version for ipfw fwd IPv6 support)
Sponsored by: Sandvine Incorporated
PR: bin/117214
MFC after: 4 weeks
Approved by: re (kib)

Add possibility to pass IPv6 packets to a divert(4) socket.

Submitted by: sem

Do not use SET_HOST_IPLEN() macro for IPv6 packets.

PR: kern/157239
MFC after: 2 weeks

After some off-list discussion, revert a number of changes to the
DPCPU_DEFINE and VNET_DEFINE macros, as these cause problems for various
people working on the affected files. A better long-term solution is
still being considered. This reversal may give some modules empty
set_pcpu or set_vnet sections, but these are harmless.

Changes reverted:

------------------------------------------------------------------------
r215318 | dim | 2010-11-14 21:40:55 +0100 (Sun, 14 Nov 2010) | 4 lines

Instead of unconditionally emitting .globl's for the __start_set_xxx and
__stop_set_xxx symbols, only emit them when the set_vnet or set_pcpu
sections are actually defined.

------------------------------------------------------------------------
r215317 | dim | 2010-11-14 21:38:11 +0100 (Sun, 14 Nov 2010) | 3 lines

Apply the STATIC_VNET_DEFINE and STATIC_DPCPU_DEFINE macros throughout
the tree.

------------------------------------------------------------------------
r215316 | dim | 2010-11-14 21:23:02 +0100 (Sun, 14 Nov 2010) | 2 lines

Add macros to define static instances of VNET_DEFINE and DPCPU_DEFINE.

Apply the STATIC_VNET_DEFINE and STATIC_DPCPU_DEFINE macros throughout
the tree.

fix breakage in in-kernel NAT: the code did not honor
net.inet.ip.fw.one_pass and always moved to the next rule
in case of a successful nat.

This should fix several related PR (waiting for feedback
before closing them)

PR: 145167 149572 150141
MFC after: 3 days

whitespace fixes (trailing whitespace, bad indentation
after a merge, etc.)

Bring in the most recent version of ipfw and dummynet, developed
and tested over the past two months in the ipfw3-head branch. This
also happens to be the same code available in the Linux and Windows
ports of ipfw and dummynet.

The major enhancement is a completely restructured version of
dummynet, with support for different packet scheduling algorithms
(loadable at runtime), faster queue/pipe lookup, and a much cleaner
internal architecture and kernel/userland ABI which simplifies
future extensions.

In addition to the existing schedulers (FIFO and WF2Q+), we include
a Deficit Round Robin (DRR or RR for brevity) scheduler, and a new,
very fast version of WF2Q+ called QFQ.

Some test code is also present (in sys/netinet/ipfw/test) that
lets you build and test schedulers in userland.

Also, we have added a compatibility layer that understands requests
from the RELENG_7 and RELENG_8 versions of the /sbin/ipfw binaries,
and replies correctly (at least, it does its best; sometimes you
just cannot tell who sent the request and how to answer).
The compatibility layer should make it possible to MFC this code in a
relatively short time.

Some minor glitches (e.g. handling of ipfw set enable/disable,
and a workaround for a bug in RELENG_7's /sbin/ipfw) will be
fixed with separate commits.

CREDITS:
This work has been partly supported by the ONELAB2 project, and
mostly developed by Riccardo Panicucci and myself.
The code for the qfq scheduler is mostly from Fabio Checconi,
and Marta Carbone and Francesco Magno have helped with testing,
debugging and some bug fixes.

check that we have an ipv4 packet before swapping ip_len and ip_off.
This should fix the handling of ipv6 packets which i broke when i
made ipfw operate on packets in network format.

Reported by: Hajimu UMEMOTO

some header shuffling to help decoupling ip_divert from ipfw

this file does not require ip_dummynet.h

Various cleanup done in ipfw3-head branch including:
- use a uniform mtag format for all packets that exit and re-enter
the firewall in the middle of a rulechain. On reentry, all tags
containing reinject info are renamed to MTAG_IPFW_RULE so the
processing is simpler.

- make ipfw and dummynet use ip_len and ip_off in network format
everywhere. Conversion is done only once instead of tracking
the format in every place.

- use a macro FREE_PKT to dispose of mbufs. This eases portability.

On passing i also removed a few typos, staticise or localise variables,
remove useless declarations and other minor things.

Overall the code shrinks a bit and is hopefully more readable.

I have tested functionality for all but ng_ipfw and if_bridge/if_ethersubr.
For ng_ipfw i am actually waiting for feedback from glebius@ because
we might have some small changes to make.
For if_bridge and if_ethersubr feedback would be welcome
(there are still some redundant parts in these two modules that
I would like to remove, but first i need to check functionality).

bring the NGM_IPFW_COOKIE back into ng_ipfw.h, libnetgraph expects
to find it there. Unfortunately this reintroduces the dependency
on ip_fw_pfil.c

bring in several cleanups tested in ipfw3-head branch, namely:

r201011
- move most of ng_ipfw.h into ip_fw_private.h, as this code is
ipfw-specific. This removes a dependency on ng_ipfw.h from some files.

- move many equivalent definitions of direction (IN, OUT) for
reinjected packets into ip_fw_private.h

- document the structure of the packet tags used for dummynet
and netgraph;

r201049
- merge some common code to attach/detach hooks into
a single function.

r201055
- remove some duplicated code in ip_fw_pfil. The input
and output processing uses almost exactly the same code so
there is no need to use two separate hooks.
ip_fw_pfil.o goes from 2096 to 1382 bytes of .text

r201057 (see the svn log for full details)
- macros to make the conversion of ip_len and ip_off
between host and network format more explicit

r201113 (the remaining parts)
- readability fixes -- put braces around some large for() blocks,
localize variables so the compiler does not think they are uninitialized,
do not insist on precise allocation size if we have more than we need.

r201119
- when doing a lookup, keys must be in big endian format because
this is what the radix code expects (this fixes a bug in the
recently-introduced 'lookup' option)

No ABI changes in this commit.

MFC after: 1 week

merge code from ipfw3-head to reduce contention on the ipfw lock
and remove all O(N) sequences from kernel critical sections in ipfw.

In detail:

1. introduce a IPFW_UH_LOCK to arbitrate requests from
the upper half of the kernel. Some things, such as 'ipfw show',
can be done holding this lock in read mode, whereas insert and
delete require IPFW_UH_WLOCK.

2. introduce a mapping structure to keep rules together. This replaces
the 'next' chain currently used in ipfw rules. At the moment
the map is a simple array (sorted by rule number and then rule_id),
so we can find a rule quickly instead of having to scan the list.
This reduces many expensive lookups from O(N) to O(log N).

3. when an expensive operation (such as insert or delete) is done
by userland, we grab IPFW_UH_WLOCK, create a new copy of the map
without blocking the bottom half of the kernel, then acquire
IPFW_WLOCK and quickly update pointers to the map and related info.
After dropping IPFW_LOCK we can then continue the cleanup protected
by IPFW_UH_LOCK. So userland still costs O(N) but the kernel side
is only blocked for O(1).

4. do not pass pointers to rules through dummynet, netgraph, divert etc,
but rather pass a <slot, chain_id, rulenum, rule_id> tuple.
We validate the slot index (in the array of #2) with chain_id,
and if successful do a O(1) dereference; otherwise, we can find
the rule in O(log N) through <rulenum, rule_id>

All the above does not change the userland/kernel ABI, though there
are some disgusting casts between pointers and uint32_t

Operation costs now are as follows:

Function Old Now Planned
-------------------------------------------------------------------
+ skipto X, non cached O(N) O(log N)
+ skipto X, cached O(1) O(1)
XXX dynamic rule lookup O(1) O(log N) O(1)
+ skipto tablearg O(N) O(1)
+ reinject, non cached O(N) O(log N)
+ reinject, cached O(1) O(1)
+ kernel blocked during setsockopt() O(N) O(1)
-------------------------------------------------------------------

The only (very small) regression is on dynamic rule lookup and this will
be fixed in a day or two, without changing the userland/kernel ABI

Supported by: Valeria Paoli
MFC after: 1 month

Various cosmetic cleanup of the files:
- move global variables around to reduce the scope and make them
static if possible;
- add an ipfw_ prefix to all public functions to prevent conflicts
(the same should be done for variables);
- try to pack variable declaration in an uniform way across files;
- clarify some comments;
- remove some misspelling of names (#define V_foo VNET(bar)) that
slipped in due to cut&paste
- remove duplicate static variables in different files;

MFC after: 1 month

Start splitting ip_fw2.c and ip_fw.h into smaller components.
At this time we pull out from ip_fw2.c the logging functions, and
support for dynamic rules, and move kernel-only stuff into
netinet/ipfw/ip_fw_private.h

No ABI change involved in this commit, unless I made some mistake.
ip_fw.h has changed, though not in the userland-visible part.

Files touched by this commit:

conf/files
now references the two new source files

netinet/ip_fw.h
remove kernel-only definitions gone into netinet/ipfw/ip_fw_private.h.

netinet/ipfw/ip_fw_private.h
new file with kernel-specific ipfw definitions

netinet/ipfw/ip_fw_log.c
ipfw_log and related functions

netinet/ipfw/ip_fw_dynamic.c
code related to dynamic rules

netinet/ipfw/ip_fw2.c
removed the pieces that goes in the new files

netinet/ipfw/ip_fw_nat.c
minor rearrangement to remove LOOKUP_NAT from the
main headers. This require a new function pointer.

A bunch of other kernel files that included netinet/ip_fw.h now
require netinet/ipfw/ip_fw_private.h as well.
Not 100% sure i caught all of them.

MFC after: 1 month

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

Fix ipfw's initialization functions to get the correct order of evaluation
to allow vnet and non vnet operation. Move some functions from ip_fw_pfil.c
to ip_fw2.c and mode to mostly using the SYSINIT and VNET_SYSINIT handlers
instead of the modevent handler. Correct some spelling errors in comments
in the affected code. Note this bug fixes a crash in NON VIMAGE kernels when
ipfw is unloaded.

This patch is a minimal patch for 8.0
I have a much larger patch that actually fixes the underlying problems
that will be applied after 8.0

Reviewed by: zec@, rwatson@, bz@(earlier version)
Approved by: re (rwatson)
MFC after: Immediatly

Purge mergeinfo in sys/ that is either empty or a subset of the parent
mergeinfo on sys/ itself.

Approved by: re (mergeinfo blanket)

Merge the remainder of kern_vimage.c and vimage.h into vnet.c and
vnet.h, we now use jails (rather than vimages) as the abstraction
for virtualization management, and what remained was specific to
virtual network stacks. Minor cleanups are done in the process,
and comments updated to reflect these changes.

Reviewed by: bz
Approved by: re (vimage blanket)

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)

Close long existed race with net.inet.ip.fw.one_pass = 0:
If packet leaves ipfw to other kernel subsystem (dummynet, netgraph, etc)
it carries pointer to matching ipfw rule. If this packet then reinjected back
to ipfw, ruleset processing starts from that rule. If rule was deleted
meanwhile, due to existed race condition panic was possible (as well as
other odd effects like parsing rules in 'reap list').

P.S. this commit changes ABI so userland ipfw related binaries should be
recompiled.

MFC after: 1 month
Tested by: Mikolaj Golub

move kernel ipfw-related sources to a separate directory,
adjust conf/files and modules' Makefiles accordingly.

No code or ABI changes so this and most of previous related
changes can be easily MFC'ed

MFC after: 5 days

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

Permit buiding kernels with options VIMAGE, restricted to only a single
active network stack instance. Turning on options VIMAGE at compile
time yields the following changes relative to default kernel build:

1) V_ accessor macros for virtualized variables resolve to structure
fields via base pointers, instead of being resolved as fields in global
structs or plain global variables. As an example, V_ifnet becomes:

options VIMAGE: ((struct vnet_net *) vnet_net)->_ifnet
default build: vnet_net_0._ifnet
options VIMAGE_GLOBALS: ifnet

2) INIT_VNET_* macros will declare and set up base pointers to be used
by V_ accessor macros, instead of resolving to whitespace:

INIT_VNET_NET(ifp->if_vnet); becomes

struct vnet_net *vnet_net = (ifp->if_vnet)->mod_data[VNET_MOD_NET];

3) Memory for vnet modules registered via vnet_mod_register() is now
allocated at run time in sys/kern/kern_vimage.c, instead of per vnet
module structs being declared as globals. If required, vnet modules
can now request the framework to provide them with allocated bzeroed
memory by filling in the vmi_size field in their vmi_modinfo structures.

4) structs socket, ifnet, inpcbinfo, tcpcb and syncache_head are
extended to hold a pointer to the parent vnet. options VIMAGE builds
will fill in those fields as required.

5) curvnet is introduced as a new global variable in options VIMAGE
builds, always pointing to the default and only struct vnet.

6) struct sysctl_oid has been extended with additional two fields to
store major and minor virtualization module identifiers, oid_v_subs and
oid_v_mod. SYSCTL_V_* family of macros will fill in those fields
accordingly, and store the offset in the appropriate vnet container
struct in oid_arg1.
In sysctl handlers dealing with virtualized sysctls, the
SYSCTL_RESOLVE_V_ARG1() macro will compute the address of the target
variable and make it available in arg1 variable for further processing.

Unused fields in structs vnet_inet, vnet_inet6 and vnet_ipfw have
been deleted.

Reviewed by: bz, rwatson
Approved by: julian (mentor)

Optimize packet flow: if net.inet.ip.fw.one_pass != 0 and packet was
processed by ipfw once - avoid second ipfw_chk() call.
This saves us from unnecessary IPFW_RLOCK(), m_tag_find() calls and
ip/tcp/udp header parsing.

MFC after: 2 month

Implement an ipfw action to reassemble ip packets: reass.

correct some #include

IPFW's pfil hook/unhook code ignores the return values of pfil_add_hook()
and pfil_remove_hook(), so cast them to (void).

MFC after: pretty soon

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

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

Merge more of currently non-functional (i.e. resolving to
whitespace) macros from p4/vimage branch.

Do a better job at enclosing all instantiations of globals
scheduled for virtualization in #ifdef VIMAGE_GLOBALS blocks.

De-virtualize and mark as const saorder_state_alive and
saorder_state_any arrays from ipsec code, given that they are never
updated at runtime, so virtualizing them would be pointless.

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

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

Raise a bit ipfw kld priority.

Discussed on: net-, ipfw-.

1) dummynet_io() declaration has changed.
2) Alter packet flow inside dummynet: allow certain packets to bypass
dummynet scheduler. Benefits are:

- lower latency: if packet flow does not exceed pipe bandwidth, packets
will not be (up to tick) delayed (due to dummynet's scheduler granularity).
- lower overhead: if packet avoids dummynet scheduler it shouldn't reenter ip
stack later. Such packets can be fastforwarded.
- recursion (which can lead to kernel stack exhaution) eliminated. This fix
long existed panic, which can be triggered this way:
kldload dummynet
sysctl net.inet.ip.fw.one_pass=0
ipfw pipe 1 config bw 0
for i in `jot 30`; do ipfw add 1 pipe 1 icmp from any to any; done
ping -c 1 localhost

3) Three new sysctl nodes are added:
net.inet.ip.dummynet.io_pkt - packets passed to dummynet
net.inet.ip.dummynet.io_pkt_fast - packets avoided dummynet scheduler
net.inet.ip.dummynet.io_pkt_drop - packets dropped by dummynet

P.S. Above comments are true only for layer 3 packets. Layer 2 packet flow
is not changed yet.

MFC after: 3 month

Add FBSDID to all files in netinet so that people can more
easily include file version information in bug reports.

Approved by: re (kensmith)

Summer of Code 2005: improve libalias - part 2 of 2

With the second (and last) part of my previous Summer of Code work, we get:

-ipfw's in kernel nat

-redirect_* and LSNAT support

General information about nat syntax and some examples are available
in the ipfw (8) man page. The redirect and LSNAT syntax are identical
to natd, so please refer to natd (8) man page.

To enable in kernel nat in rc.conf, two options were added:

o firewall_nat_enable: equivalent to natd_enable

o firewall_nat_interface: equivalent to natd_interface

Remember to set net.inet.ip.fw.one_pass to 0, if you want the packet
to continue being checked by the firewall ruleset after being
(de)aliased.

NOTA BENE: due to some problems with libalias architecture, in kernel
nat won't work with TSO enabled nic, thus you have to disable TSO via
ifconfig (ifconfig foo0 -tso).

Approved by: glebius (mentor)

revert last change.. premature.. need to wait until if_ethersubr.c
uses pfil to get to ipfw.

Move some variables to a more likely place
and remove "temporary" stuff that is not needed any more.

Reintroduce net.inet6.ip6.fw.enable sysctl to dis/enable the ipv6 processing
seperately. Also use pfil hook/unhook instead of keeping the check
functions in pfil just to return there based on the sysctl. While here fix
some whitespace on a nearby SYSCTL_ macro.

obey opt_inet6.h and opt_ipsec.h in kernel build directory.

Requested by: hrs

Add IPv6 support to IPFW and Dummynet.

Submitted by: Mariano Tortoriello and Raffaele De Lorenzo (via luigi)

When a packet has been reinjected into ipfw(4) after dummynet(4) processing
we have a non-NULL args.rule. If the same packet later is subject to "tee"
rule, its original is sent again into ipfw_chk() and it reenters at the same
rule. This leads to infinite loop and frozen router.

Assign args.rule to NULL, any time we are going to send packet back to
ipfw_chk() after a tee rule. This is a temporary workaround, which we
will leave for RELENG_5. In HEAD we are going to make divert(4) save
next rule the same way as dummynet(4) does.

PR: kern/79546
Submitted by: Oleg Bulyzhin
Reviewed by: maxim, andre
MFC after: 3 days

Add a ng_ipfw node, implementing a quick and simple interface between
ipfw(4) and netgraph(4) facilities.

Reviewed by: andre, brooks, julian

- Reduce number of arguments passed to dummynet_io(), we already have cookie
in struct ip_fw_args itself.
- Remove redundant &= 0xffff from dummynet_io().

o Clean up interface between ip_fw_chk() and its callers:

- 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

/* -> /*- for license, minor formatting changes

Revert last change.

Andre:
First lets get major new features into the kernel in a clean and nice way,
and then start optimizing. In this case we don't have any obfusication that
makes later profiling and/or optimizing difficult in any way.

Requested by: csjp, sam

Check that DUMMYNET_LOADED before seeking dummynet m_tag.

Reviewed by: andre
MFC after: 1 week

Convert IPDIVERT into a loadable module. This makes use of the dynamic loadability
of protocols. The call to divert_packet() is done through a function pointer. All
semantics of IPDIVERT remain intact. If IPDIVERT is not loaded ipfw will refuse to
install divert rules and natd will complain about 'protocol not supported'. Once
it is loaded both will work and accept rules and open the divert socket. The module
can only be unloaded if no divert sockets are open. It does not close any divert
sockets when an unload is requested but will return EBUSY instead.

Add an additional struct inpcb * argument to pfil(9) in order to enable
passing along socket information. This is required to work around a LOR with
the socket code which results in an easy reproducible hard lockup with
debug.mpsafenet=1. This commit does *not* fix the LOR, but enables us to do
so later. The missing piece is to turn the filter locking into a leaf lock
and will follow in a seperate (later) commit.

This will hopefully be MT5'ed in order to fix the problem for RELENG_5 in
forseeable future.

Suggested by: rwatson
A lot of work by: csjp (he'd be even more helpful w/o mentor-reviews ;)
Reviewed by: rwatson, csjp
Tested by: -pf, -ipfw, LINT, csjp and myself
MFC after: 3 days

LOR IDs: 14 - 17 (not fixed yet)

If we have to 'ipfw fwd'-tag a packet the second time in ipfw_pfil_out() don't
prepend an already existing tag again. Instead unlink it and prepend it again
to have it as the first tag in the chain.

PR: kern/71380

Make 'ipfw tee' behave as inteded and designed. A tee'd packet is copied
and sent to the DIVERT socket while the original packet continues with the
next rule. Unlike a normally diverted packet no IP reassembly attemts are
made on tee'd packets and they are passed upwards totally unmodified.

Note: This will not be MFC'd to 4.x because of major infrastucture changes.

PR: kern/64240 (and many others collapsed into that one)

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.

Revert the last change to sys/modules/ipfw/Makefile and fix a
standalone module build in a better way.

Silence from: andre
MFC after: 3 days

Fix a stupid typo which prevented an ipfw KLD unload from successfully cleaning
up its remains. Do not terminate 'if' lines with ';'.

Spotted by: claudio@OpenBSD.ORG (sitting 3m from my desk)
Pointy hat to: andre

Give a useful error message if someone tries to compile IPFIREWALL into the
kernel without specifying PFIL_HOOKS as well.

Do not unconditionally ignore IPDIVERT and IPFIREWALL_FORWARD when building
the ipfw KLD.

For IPFIREWALL_FORWARD this does not have any side effects. If the module
has it but not the kernel it just doesn't do anything.

For IPDIVERT the KLD will be unloadable if the kernel doesn't have IPDIVERT
compiled in too. However this is the least disturbing behaviour. The user
can just recompile either module or the kernel to match the other one. The
access to the machine is not denied if ipfw refuses to load.

Bring back the sysctl 'net.inet.ip.fw.enable' to unbreak the startup scripts
and to be able to disable ipfw if it was compiled directly into the kernel.

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)