freebsd kernel with SKQ
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Bill Paul a6e95b4420 Improve DoS avoidance in RPC stream oriented transports. The TCP transport
uses readtcp() to gather data from the network; readtcp() uses select(),
with a timeout of 35 seconds. The problem with this is that if you
connect to a TCP server, send two bytes of data, then just pause, the
server will remain blocked in readtcp() for up to 35 seconds, which is
sort of a long time. If you keep doing this every 35 seconds, you can
keep the server occupied indefinitely.

To fix this, I modified readtcp() (and its cousin, readunix() in svc_unix.c)
to monitor all service transport handles instead of just the current socket.
This allows the server to keep handling new connections that arrive while
readtcp() is running. This prevents one client from potentially monopolizing
a server.

Also, while I was here, I fixed a bug in the timeout calculations. Someone
attempted to adjust the timeout so that if select() returned EINTR and the
loop was restarted, the timeout would be reduced so that rather than waiting
for another 35 seconds, you could never wait for more than 35 seconds total.
Unfortunately, the calculation was wrong, and the timeout could expire much
sooner than 35 seconds.
1998-05-18 16:12:13 +00:00
bin Correct use of .Nm. Add rcsid. 1998-05-18 06:51:59 +00:00
contrib Make a bit of FreeBSD-specific code a bit more specific => i386 only. 1998-05-13 22:55:44 +00:00
crypto Fix nasty typo that randomly caused kinit to not properly deduce the 1998-03-29 07:27:43 +00:00
etc replaced check_rcpt ruleset with one 1998-05-17 23:05:16 +00:00
games Cast pointers to longs, not ints. 1998-05-09 11:33:22 +00:00
gnu Change the order of the include paths so that the architecture specific 1998-05-15 06:42:37 +00:00
include nuke signanosleep(). 1998-05-14 11:33:04 +00:00
kerberos5 Fix a break in the includes where the build blows chunks if it is 1997-10-02 15:03:23 +00:00
kerberosIV Debogotify. ln -f should be ln -s to allow the obj/ dir to be 1998-03-28 07:47:05 +00:00
lib Improve DoS avoidance in RPC stream oriented transports. The TCP transport 1998-05-18 16:12:13 +00:00
libexec Back out "always UTC" fix since some people want visually identical 'ls' 1998-05-18 00:06:28 +00:00
lkm The FreeBSD lkm design is aout specific. 1998-05-15 11:57:05 +00:00
release Go back to 240640 split size. Interesting experiment but somebody 1998-05-12 08:02:48 +00:00
sbin Make this safe for an alpha build, leaving out just about everything 1998-05-18 04:46:29 +00:00
secure Staticise a variable. 1997-10-08 07:02:48 +00:00
share syscons is i386 specific due to machine/console.h 1998-05-15 11:55:47 +00:00
sys 1. Don't use "nosys" and generate coredumps for unconfigured 1998-05-18 12:53:45 +00:00
tools Updates to support adding driver files outside the i386 area. 1998-05-06 05:45:17 +00:00
usr.bin Include correct header to get definition of struct sockaddr_un. 1998-05-16 21:35:37 +00:00
usr.sbin replaced check_rcpt ruleset with one 1998-05-17 22:58:51 +00:00
COPYRIGHT This is the official 4.4 Lite copyright. 1994-09-11 07:53:28 +00:00
Makefile Make perl a build tool since it is required during a make depend. 1998-05-18 03:28:02 +00:00
Makefile.alpha Add perl to the list of build tools because it is needed to build the 1998-05-12 23:11:58 +00:00
README Note that /etc is not installed by world target either. 1997-08-09 14:36:20 +00:00

This is the top level of the FreeBSD source directory.  This file
was last revised on: $Id: README,v 1.10 1997/02/23 09:18:39 peter Exp $

For copyright information, please see the file COPYRIGHT in this
directory (additional copyright information also exists for some
sources in this tree - please see the specific source directories for
more information).

The Makefile in this directory supports a number of targets for
building components (or all) of the FreeBSD source tree, the most
commonly used one being ``world'', which rebuilds and installs
everything in the FreeBSD system from the source tree except the
kernel and the contents of /etc.  Please see the top of the Makefile
in this directory for more information on the standard build targets
and compile-time flags.

Building a kernel with config(8) is a somewhat more involved process,
documentation for which can be found at:
   http://www.freebsd.org/handbook/kernelconfig.html
And in the config(8) man page.

The sample kernel configuration files reside in the sys/i386/conf
sub-directory (assuming that you've installed the kernel sources), the
file named GENERIC being the one used to build your initial installation
kernel.  The file LINT contains entries for all possible devices, not
just those commonly used, and is meant more as a general reference
than an actual kernel configuration file (a kernel built from it
wouldn't even run).


Source Roadmap:
---------------
bin		System/User commands.

contrib		Packages contributed by 3rd parties.

eBones		Kerberos package - NOT FOR EXPORT!

etc		Template files for /etc

games		Amusements.

gnu		Various commands and libraries under the GNU Public License.
		Please see gnu/COPYING* for more information.

include		System include files.

lib		System libraries.

libexec		System daemons.

lkm		Loadable Kernel Modules.

release		Release building Makefile & associated tools.

sbin		System commands.

secure		DES and DES-related utilities - NOT FOR EXPORT!

share		Shared resources.

sys		Kernel sources.

tools		Utilities for regression testing and miscellaneous tasks.

usr.bin		User commands.

usr.sbin	System administration commands.


For information on synchronizing your source tree with one or more of
the FreeBSD Project's development branches, please see:

  http://www.freebsd.org/handbook/synching.html