syn_cache_unreach() should remove the entry, or just continue on.
Algorithm is to only remove the entry if we've had more than one unreach
error and have retransmitted 3 or more times. This prevents the following
scenario, as noted in PR #5909 (PR from Ty Sarna, scenario from
Charles Hannum):
* Host A sends a SYN.
* Host A retransmits the SYN.
* Host B gets the first SYN and sends a SYN-ACK.
* Host B gets the second SYN and sends a SYN-ACK.
* One of the SYN-ACK bounces with an
ICMP unreachable, causing the `SYN cache' entry to be
removed with no notification.
* Host A receives the other SYN-ACK, sends an ACK, and goes to
ESTABLISHED state.
Should fix PR #5909.
suggestion in draft-floyd-incr-init-win-03. Rather than scaling cwnd back
by the ratio of new segment size to old segment size, we perform a slow start
using the Initial Window, computed with the new segment size.
from the output flags for CLOSING state. There is no harm in retransmitting
the FIN, and this change has unexpected side effects that break simultaneous
close behaviour.
NETHER, NFDDI, NARC are not used anywhere. Remove #include "ether.h",
which had no effect.
Removes clash with "options NATM" for native-ATM network protocol stack.
(1.44) missed a test for the right interface, making some machines answer
to some bogus arp requests (like for WHO-HAS 127.0.0.1).
The quick patch in 1.46-1.47 does not work for so-called "unnumbered"
interfaces, that is, (point-to-point) interfaces that share their local
address with another (e.g., the Ethernet) interface.
We add a macro to in_var.h, to step (in the current implementation) through
the hash chain and fine more entries with the same address, and use that
in if_arp.c to find one which belongs to our interface.
as with user-land programs, include files are installed by each directory
in the tree that has includes to install. (This allows more flexibility
as to what gets installed, makes 'partial installs' easier, and gives us
more options as to which machines' includes get installed at any given
time.) The old SYS_INCLUDES={symlinks,copies} behaviours are _both_
still supported, though at least one bug in the 'symlinks' case is
fixed by this change. Include files can't be build before installation,
so directories that have includes as targets (e.g. dev/pci) have to move
those targets into a different Makefile.
- Don't use home-grown queue manipulation. Use <sys/queue.h> instead. The
data structures are a little larger, but we are otherwise wasting the
memory chunk anyway (we're already a 64-byte malloc bucket).
- Fix a bug in the cache-is-full case: if the oldest element removed from
the first non-empty bucket was the only element in the bucket, the
bucket wouldn't be removed from the bucket cache, causing queue corruption
later.
- Optimize the syn cache timers by using PRT timers rather than home-grown
decrement-and-propagate timers.
This code is now a fair bit smaller, and significantly easier to read
and understand.
the protocol dispatch layer for TCP timers. This saves having to
modify a potentially large number of timer values (which were shorts,
and expanded to ... a lot of code on the Alpha).
- kern/5381 (Dennis Ferguson): check IP header checksum in fast forward
code.
- In ipflow_slowtimo(), if no IP flows are in use, don't bother checking
all of the hash buckets.
flow, by setting the "can fast forward" flag in the packet header, and
giving a chance for filters to clear the flag. If the flag is still
set after the filters have given it a chance, the packet will be used
to create a fast-forward flow entry.
the burst size allowed, but rather a fixed number of packets, as
described in the Internet Draft. Default allowed burst is 4 packets,
per the Draft.
Make the use of CWM and the allowed burst size tunable via sysctl.
if_fddisubr.c to fastpath IP forwarding. If ip_forward successfully
forwards a packet, it will create a cache (ipflow) entry. ether_input
and fddi_input will first call ipflow_fastforward with the received
packet and if the packet passes enough tests, it will be forwarded (the
ttl is decremented and the cksum is adjusted incrementally).
conditional (tcp_compat_42). The kernel config option TCP_COMPAT_42
will still enable this by default, or disable this by default if the
option is not included (i.e. current behavior). This will be made a
sysctl soon.
rule was to update the timestamp if the sequence numbers are in range. New
rule adds a check that the timestamp is advancing, thus preventing our notion
of the most recent timestamp from incorrectly moving backwards.