The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.
Discussed with: pfg
MFC After: 3 days
Sponsored by: Netflix
The packet_limit can fall to 0, leading to a divide by zero abort in
the "packets % packet_limit".
An possible solution would be to apply a lower limit of 1 after the
calculation of packet_limit, but since any number modulo 1 gives 0,
the more efficient solution is to skip the modulo operation for
packet_limit <= 1.
Since this is a fix for a panic observed in stable/12, merging this
fix to stable/12 and stable/13 before expiry of the 3 day waiting
period might be justified, if it works for the reporter of the issue.
Reported by: Karl Denninger <karl@denninger.net>
MFC after: 3 days
The kernel part of ipfw(8) does initialize LibAlias uncondistionally
with an zeroized port range (allowed ports from 0 to 0). During
restucturing of libalias, port ranges are used everytime and are
therefor initialized with different values than zero. The secondary
initialization from ipfw (and probably others) overrides the new
default values and leave the instance in an unfunctional state. The
obvious solution is to detect such reinitializations and use the new
default value instead.
MFC after: 3 days
The expiration time of direct address mappings is explicitly
uninitialized. Expire times are always compared during housekeeping.
Despite the uninitialized value does not harm, it's simpler to just
set it to a reasonable default. This was detected during valgrinding
the test suite.
MFC after: 3 days
Compiling libalias results in warnings about unused functions.
Those warnings are caused by clang's heuristic to consider an inline
function as in use, iff the declaration is in a *.c file.
Declarations in *.h files do not emit those warnings.
Hence the declarations must be moved to an extra *.h file.
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D30844
Current data structure is using a hash of unordered lists. Those
unordered lists are quite efficient, because the least recently
inserted entries are most likely to be used again. In order to avoid
long search times in other cases, the lists are hashed into many
buckets. Unfortunatly a search for a miss needs an exhaustive
inspection and a careful definition of the hash.
Splay trees offer a similar feature: Almost O(1) for access of the
least recently used entries, and amortized O(ln(n)) for almost all
other cases. Get rid of the hash.
Now the data structure should able to quickly react to external
packets without eating CPU cycles for breakfast, preventing a DoS.
PR: 192888
Discussed with: Dimitry Luhtionov
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D30536
Current data structure is using a hash of unordered lists. Those
unordered lists are quite efficient, because the least recently
inserted entries are most likely to be used again. In order to avoid
long search times in other cases, the lists are hashed into many
buckets. Unfortunatly a search for a miss needs an exhaustive
inspection and a careful definition of the hash.
Splay trees offer a similar feature - almost O(1) for access of the
least recently used entries), and amortized O(ln(n) - for almost all
other cases. Get rid of the hash.
Discussed with: Dimitry Luhtionov
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D30516
The entry deleteAllLinks in the struct libalias is only used to signal
a state between internal calls. It's not used between API calls.
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D30604
Get rid of PORT_BASE, replace by AliasRange. Simplify code.
Factor out the search for a new port. Improves the perfomance a bit.
Discussed with: Dimitry Luhtionov
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D30581
Let PPTP use its own data structure.
Regroup and rename other lists, which are not PPTP.
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D30580
Reorder incoming links by grouping of common search terms.
Significant performance improvement for incoming (missing) flows.
Remove LSNAT from outgoing search.
Slight speedup due to less comparsions in the loop.
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D30574
Factor out the outgoing search function.
Preparation for a new data structure.
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D30572
Separate the partially specified links into a separate data structure.
This would causes a major parformance impact, if there are many of
them. Use a (smaller) hash table to speed up the partially link
access.
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D30570
Search fully specified links first. Some performance loss due to need
to revisit the db twice, if not found.
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D30569
Factor out the common Out and In filter
Slightly better performance due to eager skip of search loop
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D30568
Summary:
- Use LibAliasTime as a real global variable for central timekeeping.
- Reduce number of syscalls in user space considerably.
- Dynamically adjust the packet counters to match the second resolution.
- Only check the first few packets after a time increase for expiry.
Discussed with: hselasky
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D30566
Replace current expensive, but sparsly called housekeeping
by a single, repetive action.
This is part of a larger restructure of libalias in order to switch to
more efficient data structures. The whole restructure process is
split into 15 reviews to ease reviewing. All those steps will be
squashed into a single commit for MFC in order to hide the
intermediate states from production systems.
Reviewed by: hselasky
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D30277
The functionality to detect a newly created link after processing a
single packet is decoupled from the packet processing. Every new
packet is processed asynchronously and will reset the indicator, hence
the function is unusable. I made a Google search for third party code,
which uses the function, and failed to find one.
That's why the function should be removed: It unusable and unused.
A much simplified API/ABI will remain in anything below 14.
Discussed with: kp
Reviewed by: manpages (bcr)
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D30275
The commit 189f8eea contains a refactorisation of a constant. During
later review D30283 the naming of the constant was improved and the
initialization became explicit. Put this into the tree, in order to
MFC the correct naming.
The field nullAddress in struct libalias is never set and never used.
It exists as a placeholder for an unused argument only.
Reviewed by: hselasky
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D30253
libalias is a convolut of various coding styles modified by a series
of different editors enforcing interesting convetions on spacing and
comments.
This patch is a baseline to start with a perfomance rework of
libalias. Upcoming patches should be focus on the code, not on the
style. That's why most annoying style errors should be fixed
beforehand.
Reviewed by: hselasky
Discussed by: emaste
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D30259
terminating a TCP connection.
If a TCP packet must be retransmitted and the data length has changed in the
retransmitted packet, due to the internal workings of TCP, typically when ACK
packets are lost, then there is a 30% chance that the logic in GetDeltaSeqOut()
will find the correct length, which is the last length received.
This can be explained as follows:
If a "227 Entering Passive Mode" packet must be retransmittet and the length
changes from 51 to 50 bytes, for example, then we have three cases for the
list scan in GetDeltaSeqOut(), depending on how many prior packets were
received modulus N_LINK_TCP_DATA=3:
case 1: index 0: original packet 51
index 1: retransmitted packet 50
index 2: not relevant
case 2: index 0: not relevant
index 1: original packet 51
index 2: retransmitted packet 50
case 3: index 0: retransmitted packet 50
index 1: not relevant
index 2: original packet 51
This patch simply changes the searching order for TCP packets, always starting
at the last received packet instead of any received packet, in
GetDeltaAckIn() and GetDeltaSeqOut().
Else no functional changes.
Discussed with: rscheff@
Submitted by: Andreas Longwitz <longwitz@incore.de>
PR: 230755
MFC after: 1 week
Sponsored by: Mellanox Technologies // NVIDIA Networking
to be a true RFC 6598 NAT444 setup, where each network segment (e.g. user,
subnet) can have their own dedicated port aliasing ranges.
Reviewed by: donner, kp
Approved by: 0mp (mentor), donner, kp
Differential Revision: https://reviews.freebsd.org/D23450
This fixes -Wcast-align warnings caused by the underaligned `struct ip`.
This also silences them in the public functions by changing the function
signature from char * to void *. This is source and binary compatible and
avoids the -Wcast-align warning.
Reviewed By: ae, gbe (manpages)
Differential Revision: https://reviews.freebsd.org/D27882
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.
The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
No functional change intended.
- Remove locking, since all module(9) events are running under &Giant.
- Use TAILQ for protocol handlers and fix a bug which led to
infinite cycle. Bug found in VirtualBox [1]
- Simplify code everywhere.
- Fix documentation.
[1] https://www.virtualbox.org/pipermail/vbox-dev/2013-November/011936.html
PR: 183792 [1]
Submitted by: Valery Ushakov <uwe NetBSD.org> [1]
Sponsored by: Nginx, Inc.
alias address needs to be specified.
Add inbound handler to the alias_ftp module. It helps handle active
FTP transfer mode for the case with external clients and FTP server behind
NAT. Fix passive FTP transfer case for server behind NAT using redirect with
external IP address different from NAT ip address.
PR: kern/157957
Submitted by: Alexander V. Chernikov
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
translation. It turns out this is useful for applications which require
source port randomization for security (i.e. dns servers).
Discussed with: secteam
Requested by: mlaier
MFC after: 2 weeks
to reduce performance degradation under heavy outgoing scan/flood.
Scalability is now much more important then several kilobytes of RAM.
Remove unneded TCP-specific expiration handeling. Before this connected
TCP sessions could never expire. Now connected TCP sessions will expire
after 24hours of inactivity.
Simplify HouseKeeping() to avoid several mul/div-s per packet. Taking into
account increased LINK_TABLE_OUT_SIZE, precision is still much more then
required.
restrict the utilization of direct pointers to the content of
ip packet. These modifications are functionally nop()s thus
can be merged with no side effects.
o fixed a comment
o made in kernel libalias a bit less verbose (disabled automatic
logging everytime a new link is added or deleted)
Approved by: glebius (mentor)
With the first part of my previous Summer of Code work, we get:
-made libalias modular:
-support for 'particular' protocols (like ftp/irc/etcetc) is no more
hardcoded inside libalias, but it's available through external
modules loadable at runtime
-modules are available both in kernel (/boot/kernel/alias_*.ko) and
user land (/lib/libalias_*)
-protocols/applications modularized are: cuseeme, ftp, irc, nbt, pptp,
skinny and smedia
-added logging support for kernel side
-cleanup
After a buildworld, do a 'mergemaster -i' to install the file libalias.conf
in /etc or manually copy it.
During startup (and after every HUP signal) user land applications running
the new libalias will try to read a file in /etc called libalias.conf:
that file contains the list of modules to load.
User land applications affected by this commit are ppp and natd:
if libalias.conf is present in /etc you won't notice any difference.
The only kernel land bit affected by this commit is ng_nat:
if you are using ng_nat, and it doesn't correctly handle
ftp/irc/etcetc sessions anymore, remember to kldload
the correspondent module (i.e. kldload alias_ftp).
General information and details about the inner working are available
in the libalias man page under the section 'MODULAR ARCHITECTURE
(AND ipfw(4) SUPPORT)'.
NOTA BENE: this commit affects _ONLY_ libalias, ipfw in-kernel nat
support will be part of the next libalias-related commit.
Approved by: glebius
Reviewed by: glebius, ru
