MFC r313821 r315277 r315286

Use inet_ntoa_r() instead of inet_ntoa() throughout the kernel.

inet_ntoa() cannot be used safely in a multithreaded environment
because it uses a static local buffer. Instead, use inet_ntoa_r()
with a buffer on the caller's stack, except for KTR messages.
KTR can correctly log the immediate integral values passed to it,
as well as constant strings, but not non-constant strings,
since they might change by the time ktrdump retrieves them.
Therefore, use hex notation in KTR messages.

Sponsored by: Dell EMC

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

Avoid potential bad pointer dereference.

Previously RuleAdd would leave entry->la unset for the first entry in
the proxyList.

Sponsored by: ADARA Networks
MFC After: 1 week

Move inet_aton() (specular to inet_ntoa(), already present in libkern)
into libkern in order to made it usable by other modules than alias_proxy.

Obtained from: Sandvine Incorporated
Sponsored by: Sandvine Incorporated
MFC: 1 week

MFP4:
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 Kill EOLWS while I'm here.

o Fix strtoul() error conditions check.

PR: kern/108211
Submitted by: Yong Tang
MFC after: 2 weeks

Do not assign result of (char *) cast to u_char * variable.

o made in kernel libalias mpsafe
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)

Summer of Code 2005: improve libalias - part 1 of 2

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

Disable checksum processing in LibAlias, when it works as a
kernel module. LibAlias is not aware about checksum offloading,
so the caller should provide checksum calculation. (The only
current consumer is ng_nat(4)). When TCP packet internals has
been changed and it requires checksum recalculation, a cookie
is set in th_x2 field of TCP packet, to inform caller that it
needs to recalculate checksum. This ugly hack would be removed
when LibAlias is made more kernel friendly.

Incremental checksum updates are left as is, since they don't
conflict with offloading.

Approved by: re (scottl)

Add a workaround for 64-bit archs: store unsigned long return value in
temporary variable, check it and then cast to in_addr_t.

s/DEBUG/LIBALIAS_DEBUG/, since DEBUG is defined in LINT and
not supported for kernel build.

More bits for kernel version:
- copy inet_aton() from libc
- disable getservbyname() lookup and accept only numeric port

Always include alias.h before alias_local.h

Fix argument order for bcopy() in last commit.

Noticed by: njl
Pointy hat to: glebius

Use bcopy() instead of memmove().

Play with includes so that libalias can be compiled both as userland
library and kernel module.

Introduce inline {ip,udp,tcp}_next() functions which take a pointer to an
{ip,udp,tcp} header and return a void * pointing to the payload (i.e. the
first byte past the end of the header and any required padding). Use them
consistently throughout libalias to a) reduce code duplication, b) improve
code legibility, c) get rid of a bunch of alignment warnings.

Make libalias WARNS?=6-clean. This mostly involves renaming variables
named link, foo_link or link_foo to lnk, foo_lnk or lnk_foo, fixing
signed / unsigned comparisons, and shoving unused function arguments
under the carpet.

I was hoping WARNS?=6 might reveal more serious problems, and perhaps
the source of the -O2 breakage, but found no smoking gun.

Parenthesize return values.

Mechanical whitespace cleanup.

Run through indent(1) so I can read the code without getting a headache.
The result isn't quite knf, but it's knfer than the original, and far
more consistent.

Mostly mechanical rework of libalias:

Makes it possible to have multiple packet aliasing instances in a
single process by moving all static and global variables into an
instance structure called "struct libalias".

Redefine a new API based on s/PacketAlias/LibAlias/g

Add new "instance" argument to all functions in the new API.

Implement old API in terms of the new API.

Correct typos, mostly s/ a / an / where appropriate. Some whitespace cleanup,
especially in troff files.

Remove trailing whitespace

cmott@scientech.com -> cm@linktel.net

Requested by: Charles Mott <cmott@scientech.com>

Add __FBSDID's to libalias

Add BSD-style copyright headers

Approved by: Charles Mott <cmott@scientech.com>

Remove an extraneous declaration.

Ignore leading witespace in the string given to PacketAliasProxyRule().

strtok -> strsep (no strtok allowed in libraries)
add unsigned char cast to ctype macro

Add $FreeBSD$ and spell Eklund properly.

Approved by: brian (well, he approved adding $Id$)

Add a ``const'' and remove some inconsistent prototype args.

Remove all diagnostics to stdout/stderr with #ifdef DEBUG
Statify functions in alias_nbt.c

Version 3.0: January 1, 1999
- Transparent proxying support added.
- PPTP redirecting support added based on patches
contributed by Dru Nelson <dnelson@redwoodsoft.com>.

Submitted by: Charles Mott <cmott@srv.net>