DeviceType = multicast allows one to specify a multicast address and port with
a Device statement. Tinc will then read/send packets to that multicast group
instead of to a tun/tap device. This allows interaction with UML, QEMU and KVM
instances that are listening on the same group.
When making outgoing connections, tinc goes through the list of Addresses and
tries all of them until one succeeds. However, before it would consider
establishing a TCP connection a success, even when the authentication failed.
This would be a problem if the first Address would point to a hostname and port
combination that belongs to the wrong tinc node, or perhaps even to a non-tinc
service, causing tinc to endlessly try this Address instead of moving to the
next one.
Problem found by Delf Eldkraft.
* Everything is identical except the headers of the records.
* Instead of sending explicit message length and having an implicit sequence
number, datagram mode has an implicit message length and an explicit sequence
number.
* The sequence number is used to set the most significant bytes of the counter.
Seeking in files and rewriting parts of them does not seem to work properly on
Windows. Instead, when old RSA keys are found when generating new ones, the
file containing the old keys is copied to a temporary file where the changes
are made, and that file is renamed back to the original filename. On Windows,
we cannot atomically replace files with a rename(), so we need to move the
original file out of the way first. If anything fails, the new code will warn
that the user has to solve the problem by hand.
This allows tincctl to receive log messages from a running tincd,
independent of what is logged to syslog or to file. Tincctl can receive
debug messages with an arbitrary level.
This allows administrators who frequently want to work with one tinc
network to omit the -n option. Since the NETNAME variable is set by
tincd when executing scripts, this makes it slightly easier to use
tincctl from within scripts.
The Broadcast option can be used to cause tinc to drop all broadcast and
multicast packets. This option might be expanded in the future to selectively
allow only some broadcast packet types.
The code introduced in commit 41a05f59ba is not
needed anymore, since tinc has been able to handle UDP packets from a different
source address than those of the TCP packets since 1.0.10. When using multiple
BindToAddress statements, this code does not make sense anymore, we do want the
kernel to choose the source address on its own.
Tinc will now, by default, decrement the TTL field of incoming IPv4 and IPv6
packets, before forwarding them to the virtual network device or to another
node. Packets with a TTL value of zero will be dropped, and an ICMP Time
Exceeded message will be sent back.
This behaviour can be disabled using the DecrementTTL option.
Scripts called by tinc would inherit its open filedescriptors. This could
be a problem if other long-running daemons are started from those scripts,
if those daemons would not close all filedescriptors before going into the
background.
Problem found and solution suggested by Nick Hibma.
