Changes since 1.0.9:
* Mark Forwarding and DirectOnly options as being experimental.
* Don't redefine MAX if it already exists.
* Fixes for definitions under Windows.
* Ensure subnet-up/down scripts are called after HUP when necessary.
* Fix reloading Subnets when StrictSubnets is set.
* Reload Subnets when getting a HUP signal and StrictSubnets is used.
* Ensure ICMP_NET_ANO is defined.
* Convert Port to numeric form before sending it to other nodes.
If one uses a symbolic name for the Port option, tinc will send that name
literally to other nodes. However, it is not guaranteed that all nodes have
the same contents in /etc/services, or have such a file at all.
* Never delete Subnets when StrictSubnets is set
If a node is unreachable, and not connected to an edge anymore, it gets
deleted. When this happens its subnets are also removed, which should
not happen with StrictSubnets=yes.
Solution:
- do not remove subnets in src/net.c::purge(), we know that all subnets
in the list came from our hosts files.
I think here you got the check wrong by looking at the tunnelserver
code below it - with strictsubnets we still inform others but do not
remove the subnet from our data.
- do not remove nodes in net.c::purge() that still have subnets
attached.
* Log unauthorized Subnets when StrictSubnets is set.
* ConnectTo does not mean tinc does not listen for incoming connections anymore.
* Fixes for the Forwarding option.
* Add the DirectOnly option.
When this option is enabled, packets that cannot be sent directly to the destination node,
but which would have to be forwarded by an intermediate node, are dropped instead.
When combined with the IndirectData option,
packets for nodes for which we do not have a meta connection with are also dropped.
* Add the Forwarding option.
This determines if and how incoming packets that are not meant for the local
node are forwarded. It can either be off, internal (tinc forwards them itself,
as in previous versions), or kernel (packets are always sent to the TUN/TAP
device, letting the kernel sort them out).
* Add the StrictSubnets option.
When this option is enabled, tinc will not accept dynamic updates of Subnets
from other nodes, but will only use Subnets read from local host config files
to build its routing table.
* Preload all Subnets in TunnelServer mode.
This simplifies the logic in protocol_subnet.c.
* Check for dirent.h.
* Simplify reading lines from configuration files.
Instead of allocating storage for each line read, we now read into fixed-size
buffers on the stack. This fixes a case where a malformed configuration file
could crash tinc.
* Clamp MSS to miminum MTU in both directions.
Clamp MSS of both incoming and outgoing packets, and use the minimum of the
PMTU of both directions when clamping.
* Add --disable-zlib configure option
* Add --disable-lzo configure option
* Ensure peers with a meta connection always have our key.
This keeps UDP probes going, which in turn keeps NAT mappings alive.
* Update copyright notices.
* Try to set DF bit on BSDs as well.
Every operating system seems to have its own, slightly different way to disable
packet fragmentation. Emit a compiler warning when no suitable way is found.
On OpenBSD, it seems impossible to do it for IPv4.
* Immediately exchange keys when establishing a meta connection.
This in turn will trigger PMTU discovery, and ensures nodes know each others
reflexive UDP address and port.
* Determine peer's reflexive address and port when exchanging keys.
To help peers that are behind NAT connect to each other directly via UDP, they
need to know the exact external address and port that they use. Keys exchanged
between NATted peers necessarily go via a third node, which knows this address
and port, and can append this information to the keys, which is in turned used
by the peers.
Since PMTU discovery will immediately trigger UDP communication from both sides
to each other, this should allow direct communication between peers behind
full, address-restricted and port-restricted cone NAT.
* Be liberal in accepting KEY_CHANGED/REQ_KEY/ANS_KEY requests.
When we got a key request for or from a node we don't know, we disconnected the
node that forwarded us that request. However, especially in TunnelServer mode,
disconnecting does not help. We now ignore such requests, but since there is no
way of telling the original sender that the request was dropped, we now retry
sending REQ_KEY requests when we don't get an ANS_KEY back.
* Run subnet-up/down scripts for local MAC addresses as well.
* Fix subnet-up/down scripts being called with an empty SUBNET.
Commit 052ff8b2c598358d1c5febaa9f9f5fc5d384cfd3 contained a bug that causes
scripts to be called with an empty, or possibly corrupted SUBNET variable when
a Subnet is added or removed while the owner is still online. In router mode,
this normally does not happen, but in switch mode this is normal.
* Make MSS clamping configurable, but enabled by default.
It can either be set globally in tinc.conf, or per-node in host config files.
* Also clamp MSS of TCP over IPv6 packets.
* Optimise handling of select() returning <= 0.
Before, we immediately retried select() if it returned -1 and errno is EAGAIN
or EINTR, and if it returned 0 it would check for network events even if we
know there are none. Now, if -1 or 0 is returned we skip checking network
events, but we do check for timer and signal events.
* Ping nodes immediately when receiving SIGALRM.
One reason to send the ALRM signal is to let tinc immediately try to connect to
outgoing nodes, for example when PPP or DHCP configuration of the outgoing
interface finished. Conversely, when the outgoing interface goes down one can
now send this signal to let tinc quickly detect that links are down too.
* Clamp MSS of IPv4 SYN packets.
Some ISPs block the ICMP Fragmentation Needed packets that tinc sends. We
clamp the MSS of IPv4 SYN packets to prevent hosts behind those ISPs from
sending too large packets.
* Allow Port and PMTUDiscovery options in tinc.conf, always enable PMTUDiscovery by default.
* Use xstrdup() instead of xasprintf() to copy static strings.
* Allow port to be specified in Address statements.
This allows one to connect to use more than one port number to connect to
another node. The syntax is now:
Address = <hostname> [<port>]
* Do not fragment packets smaller than RFC defined minimum MTUs.
For IPv6, the minimum MTU is 1280 (RFC 2460), for IPv4 the minimum is actually
68, but this is such a low limit that it will probably hurt performance, so we
do as if it is 576 (the minimum packet size hosts should be able to handle, RFC
791). If we detect a path MTU smaller than those minima, and we have to handle
a packet that is bigger than the PMTU but smaller than those minima, we forward
them via TCP instead of fragmenting or returning ICMP packets.
* Forget addresses of unreachable nodes.
We clear the cached address used for UDP connections when a node becomes
unreachable. This also prevents host-up scripts from passing the old, cached
address from when the host becomes reachable again from a different address.
* Remove unused variable in lookup_subnet_*() functions.
* When learning MAC addresses, only check our own Subnets for previous entries.
Before it would check all addresses, and not learn an address if another node
already claimed that address. This caused fast roaming to fail, the code from
commit 6f6f426b353596edca77829c0477268fc2fc1925 was never triggered.
* Start a tinc service if it already exists.
* Fast handoff of roaming MAC addresses.
In switch mode, if a known MAC address is claimed by a second node before it
expired at the first node, it is likely that this is because a computer has
roamed from the LAN of the first node to that of the second node. To ensure
packets for that computer are routed to the second node, the first node should
delete its corresponding Subnet as soon as possible, without waiting for the
normal expiry timeout.
* Move socket error interpretation to utils.h.
* Use WSAGetLastError() to determine cause of network errors on Windows.
This reduces log spam and lets path MTU discovery work faster.
* Remove localedir leftovers.
* Use IP_DONTFRAGMENT instead of IP_MTU_DISCOVER on Windows.
This ensures the DF bit on outgoing UDP packets gets set on Windows when path
MTU discovery is enabled, reducing fragmentation.
* Forward packets to not directly reachable hosts via UDP if possible.
If MTU probing discovered a node was not reachable via UDP, packets for it were
forwarded to the next hop, but always via TCP, even if the next hop was
reachable via UDP. This is now fixed by retrying to send the packet using
send_packet() if the destination is not the same as the nexthop.
* Make maxmtu equal to minmtu when fixing the path MTU to a node.
This ensures MTU probes used to ping nodes are not too large, and prevents
restarting MTU probing unnecessarily.
* Always reply to MTU probes via UDP.
It could sometime happen that a node would return MTU probes via TCP, which
does not make a lot of sense.
* Allow UDP packets with an address different from the corresponding TCP connection.
* Use uint32_t instead of long int for connection options.
Options should have a fixed width anyway, but this also fixes a possible MinGW
compiler bug where %lx tries to print a 64 bit value, even though a long int is
only 32 bits.
* Add dummy device.
* Clarify and increase level of log message about MTU probes to unreachable nodes.
* Handle weighted Subnets in switch and hub modes.
We now handle MAC Subnets in exactly the same way as IPv4 and IPv6 Subnets.
This also fixes a problem that causes unncessary broadcasting of unicast
packets in VPNs where some daemons run 1.0.10 and some run other versions.
* Fix a possible crash when sending the HUP signal.
When the HUP signal is sent while some outgoing connections have not been made
yet, or are being retried, a NULL pointer could be dereferenced resulting in
tinc crashing. We fix this by more careful handling of outgoing_ts, and by
deleting all connections that have not been fully activated yet at the HUP
signal is received.
* Fix description of the WEIGHT environment variable.
* Include missing header.
* Remove debugging message when reading packets from a BSD device.
* Allow the cloning /dev/tap interface to be used on FreeBSD and NetBSD.
This device works like /dev/tun on Linux, automatically creating a new tap
interface when a program opens it. We now pass the actual name of the newly
created interface in $INTERFACE.
* Use MTU probes to regularly ping other nodes over UDP.
This keeps NAT mappings for UDP alive, and will also detect when a node is not
reachable via UDP anymore or if the path MTU is decreasing. Tinc will fall back
to TCP if the node has become unreachable.
If UDP communication is impossible, we stop sending probes, but we retry if it
changes its keys.
We also decouple the UDP and TCP ping mechanisms completely, to ensure tinc
properly detects failure of either method.
* Small updates to the documentation.
Mention that TCPOnly is not necessary anymore since tinc will autodetect
whether it can send via UDP or not. Also mention the WEIGHT environment
variable and the new default value (2048 bits) of RSA keys.
* Ensure that the texinfo manual can be converted to HTML.
The top node was made conditional with the @iftex command, since it should not
appear in PostScript and PDF output. However, it is still necessary for
texi2html, so we have to use @ifnottex instead.
Texi2html also complains about the use of @cindex in the copyright statement,
so we remove that.
* Revert "Raise default crypto algorithms to AES256 and SHA256."
Although it would be better to have the new defaults, only the most recent
releases of most of the platforms supported by tinc come with a version of
OpenSSL that supports SHA256. To ensure people can compile tinc and that nodes
can interact with each other, we revert the default back to Blowfish and SHA1.
* Remove code duplication when checking ADD_EDGE/DEL_EDGE messages.
* Don't disconnect clients in TunnelServer mode who send unauthorised ADD_SUBNETs.
So that we are liberal in what we accept.
* Removed last gettext function.
* Remove autogenerated files from EXTRA_DIST.
Apparently they were once necessary, but autoconf now includes them
automatically. Some of them are not used anymore, and this caused make dist to
fail.
* Update the NEWS.
* Add more authors to the copyright headers.
Git's log and blame tools were used to find out which files had significant
contributions from authors who sent in patches that were applied before we used
git.
* Drop support for localisation.
Localised messages don't make much sense for a daemon, and there is only the
Dutch translation which costs time to maintain.
* Remove checkpoint tracing.
This feature is not necessary anymore since we have tools like valgrind today
that can catch stack overflow errors before they make a backtrace in gdb
impossible.
* K&R style braces.
* Update the address of the Free Software Foundation in all copyright headers.
* Remove Ivo's old email addresses.
* Remove all occurences of $Id$.
* Update copyright information.
- Update year numbers in copyright headers.
- Add copyright information for Michael Tokarev and Florian Forster to the
copyright headers of files to which they have contributed significantly.
- Mention Michael and Florian in AUTHORS.
- Mention that tinc is GPLv3 or later if compiled with the --enable-tunemu
flag.
* Send large packets we cannot handle properly via TCP.
During the path MTU discovery phase, we might not know the maximum MTU yet, but
we do know a safe minimum. If we encounter a packet that is larger than that
the minimum, we now send it via TCP instead to ensure it arrives. We also
allow large packets that we cannot fragment or create ICMP replies for to be
sent via TCP.
* Raise default RSA key length to 2048 bits.
* Use a mutex to allow the TAP reader to process packets faster on Windows.
The TAP-Win32 device is not a socket, and select() under Windows only works
with sockets. Tinc used a separate thread to read from the TAP-Win32 device,
and passed this via a local socket to the main thread which could then select()
from it. We now use a global mutex, which is only unlocked when the main thread
is waiting for select(), to allow the TAP reader thread to process packets
directly.
* Remove extra {.
* Raise default crypto algorithms to AES256 and SHA256.
In light of the recent improvements of attacks on SHA1, the default hash
algorithm in tinc is now SHA256. At the same time, the default symmetric
encryption algorithm has been changed to AES256.
* Use access() instead of stat() for checking whether scripts exist.
* Remove dropin random() function, as it is not used anymore.
* Allow compiling for Windows XP and higher.
This allows us to use getaddrinfo(), getnameinfo() and related functions, which
allow tinc to make connections over existing IPv6 networks. These functions are
not available on Windows 2000 however. By default, support is enabled, but when
compiling for Windows 2000 the configure switch --with-windows2000 should be
used.
Since getaddrinfo() et al. are not functions but macros on Windows, we have to
use AC_CHECK_DECLS() instead of AC_CHECK_FUNCS() in configure.in.
* Also do not use drand48(), it is not available on Windows.
* Use only rand(), not random().
We used both rand() and random() in our code. Since it returns an int, we have
to use %x in our format strings instead of %lx. This fixes a crash under
Windows when cross-compiling tinc with a recent version of MinGW.
* Apparently it's impolite to ask GCC to subtract two pointers.
If two pointers do not belong to the same array, pointer subtraction gives
nonsensical results, depending on the level of optimisation and the
architecture one is compiling for. It is apparently not just subtracting the
pointer values and dividing by the size of the object, but uses some kind of
higher magic not intended for mere mortals. GCC will not warn about this at
all. Casting to void * is also a no-no, because then GCC does warn that strict
aliasing rules are being broken. The only safe way to query the ordering of two
pointers is to use the (in)equality operators.
The unsafe implementation of connection_compare() has probably caused the "old
connection_t for ... still lingering" messages. Our implementation of AVL trees
is augmented with a doubly linked list, which is normally what is traversed.
Only when deleting an old connection the tree itself is traversed.
* Remove superfluous call to avl_delete().
* Handle unicast packets larger than PMTU in switch mode.
If PMTUDiscovery is enabled, and we see a unicast packet that is larger than
the path MTU in switch mode, treat it just like we would do in router mode.
* Allow PMTUDiscovery in switch and hub modes again.
PMTUDiscovery was disabled in commit d5b56bbba56480b5565ffb38496175a7c1df60ac
because tinc did not handle packets larger than the path MTU in switch and hub
modes. We now allow it again in preparation of proper support, but default to
off.
* Put Subnet weight in a separate environment variable.
Commit 5674bba5c54c1aee3a4ac5b3aba6b3ebded91bbc introduced weighted Subnets,
but the weight was included in the SUBNET variable passed to subnet-up/down
scripts. This makes it harder to use in those scripts. The weight is now
stripped from the SUBNET variable and put in the WEIGHT variabel.
* Don't stat() on iPhone/iPod.
Grzegorz Dymarek noted that tinc segfaults at the stat() call in
execute_script() on the iPhone. We can omit the stat() call for the moment,
the subsequent call to system() will fail with just a warning.
* Add support for iPhones and recent iPods.
This is a slightly modified patch from Grzegorz Dymarek that allows tinc to use
the tunemu device, which allows tinc to be compiled for iPhones and recent
iPods. To enable support for tunemu, the --enable-tunemu option has to be used
when running the configure script.
* Another safe bitfield conversion.
* Add the GPL license to the repository.
Tinc is licensed under the GPL version 2 or later. To ensure autoconf does not
install the wrong license if COPYING is missing, we have to put the right one
in place.
* Convert bitfields to integers in a safe way.
This is commit eb391c52eed46f3f03b404553df417851fc0cb90 redone, but without the
non-standard anonymous union.
* Ensure tinc compiles with gcc -std=c99.
We use a lot of C99 features already, but also some extensions which are not in
the standard.
* UNIX signal numbers start at 1.
* Replace asprintf() by xasprintf().
* Check the return value of fscanf() when reading a PID file.
* Add xasprintf() and xvasprintf().
These functions wrap asprintf() and vasprintf(), and check the return value. If
the function failed, tinc will exit with an error message, similar to xmalloc()
and friends.
* Remove extra semicolon in my definition of setpriority()
* Always remove a node from the UDP tree before freeing it.
Valgrind caught tinc reading free'd memory during a purge(). This was caused by
first removing it from the main node tree, which will already call free_node(),
and then removing it from the UDP tree. This might cause spurious segmentation
faults.
* Change level of some debug messages, zero pointer after freeing hostname.
* Do not log errors when recvfrom() returns EAGAIN or EINTR.
Although we select() before we call recvfrom(), it sometimes happens that
select() tells us we can read but a subsequent read fails anyway. This is
harmless.
* Remove pending MTU probe events when a node's reachability status changes.
* Don't try to send MTU probes to unreachable nodes.
If there is an outstanding MTU probe event for a node which is not reachable
anymore, a UDP packet would be sent to that node, which caused a key request to
be sent to that node, which triggered a NULL pointer dereference. Probes and
other UDP packets to unreachable nodes are now dropped.
* Properly set HMAC length for incoming packets.
* try outgoing connections before chroot/drop_privs
When chrooted, we either need to force-initialize resolver
and/or nsswitch somehow (no clean way) or resolve all the
names we want before entering chroot jail. The latter
looks cleaner, easier and it is actually safe because
we still don't talk with the remote nodes there, only
initiating outgoing connections.
* cleanup setpriority thing to make it readable
* Add some const where appropriate.
* Add ProcessPriority option.
This option can be set to low, normal or high. On UNIX flavours, this changes
the nice value of the process by +10, 0 and -10 respectively. On Windows, it
sets the priority to BELOW_NORMAL_PRIORITY_CLASS, NORMAL_PRIORITY_CLASS and
HIGH_PRIORITY_CLASS respectively.
A high priority might help to reduce latency and packet loss on the VPN.
* src/net_socket.c: Bind outgoing TCP sockets to `BindToAddress'.
If a host has multiple addresses on an interface, the source address of the TCP
connection(s) was picked by the operating system while the UDP packets used a
bound socket, i. e. the source address was the address specified by the user.
This caused problems because the receiving code requires the TCP connection and
the UDP connection to originate from the same IP address.
This patch adds support for the `BindToInterface' and `BindToAddress' options
to the setup of outgoing TCP connections.
Tested with Debian Etch on x86 and Debian Lenny on x86_64.
Signed-off-by: Florian Forster <octo@verplant.org>
* src/linux/device.c: Fix segfault when running without `--net'.
If running without `--net', the (global) variable `netname' is NULL. This
creates a segmentation fault because this NULL-pointer is passed to strdup:
Program terminated with signal 11, Segmentation fault.
#0 0xb7d30463 in strlen () from /lib/tls/i686/cmov/libc.so.6
(gdb) bt
#0 0xb7d30463 in strlen () from /lib/tls/i686/cmov/libc.so.6
#1 0xb7d30175 in strdup () from /lib/tls/i686/cmov/libc.so.6
#2 0x0805bf47 in xstrdup (s=0x0) at xmalloc.c:118 <---
#3 0x0805be33 in setup_device () at device.c:66
#4 0x0805072e in setup_myself () at net_setup.c:432
#5 0x08050db2 in setup_network () at net_setup.c:536
#6 0x0805b27f in main (argc=Cannot access memory at address 0x0) at tincd.c:580
This patch fixes this by checking `netname' in `setup_device'. An alternative
would be to check for NULL-pointers in `xstrdup' and return NULL in this case.
Signed-off-by: Florian Forster <octo@verplant.org>
* tunnelserver: log which ADD_SUBNET was refused
Add some logging about refused ADD_SUBNET
(it causes subsequent client disconnect so it's
important to know which subnet was at fault).
Maybe we should just ignore it completely.
* Do not forward broadcast packets when TunnelServer is enabled.
First of all, the idea behind the TunnelServer option is to hide all other
nodes from each other, so we shouldn't forward broadcast packets from them
anyway. The other reason is that since edges from other nodes are ignored, the
calculated minimum spanning tree might not be correct, which can result in
routing loops.
* Use packet size before decompression to calculate path MTU.
Since compression can either grow or shrink a packet, the size of an MTU probe
after decompression might not reflect the real path MTU. Now we use the size
before decompression, which is independent of the compression algorithm, and
substract a safety margin such that the calculated path MTU will be safe even
for packets which grow as much as possible after compression.
* Add declaration for sockaddrcmp_noport().
* Fix ans_key exchange in recent changes
send_ans_key() was using the wrong in vs. outkeylength to
terminate the key being sent, so it was always empty.
* Use xrealloc instead of if(ptr) ptr = xmalloc().
* Fix initialisation of packet decryption context broken by commit 3308d13e7e3bf20cfeaf6f2ab17228a9820cea66.
Instead of a single, global decryption context, each node has its own context.
However, in send_ans_key(), the global context was initialised. This commit
fixes that and removes the global context completely.
Also only set status.validkey after all checks have been evaluated.
* don't log every strange packet coming to the UDP port
it's a sure way to fill up syslog. Only log those if
debug level is up to PROTOCOL
* Fix link to Mattias Nissler's tun/tap driver for MacOS/X.
* If PMTUDiscovery is not set, do not forward packets via TCP unnecessarily.
* ignore indirect edge registrations in tunnelserver mode
In tunnelserver mode we're not interested to hear about
our client edges, just like in case of subnets. Just
ignore all requests which are not about our node or the
client node.
The fix is very similar to what was done for subnets.
Note that we don't need to add the "unknown" nodes to
the list in tunnelserver mode too, so move allocation
of new nodes down the line.
* TunnelServer: Don't disconnect client on DEL_SUBNET too
Similar changes as was in 2327d3f6eb5982bcc922ff1ab1ec436ba6aeffdc
but for del_subnet_h().
Before, we vere returning false (and causing disconnect of the
client) in case of tunnelserver and the client sending DEL_SUBNET
for non-his subnet or for subnet which owner isn't in our connection
list.
After the mentioned change to add_subnet_h() that routine does not
add such indirect owners to the connection list anymore, so that
was ok (owner == NULL and we return true).
But if we too has a connection with the node about which the client
is sending DEL_SUBNET notification, say, because that client lost
connection with that other node, we'll disconnect this client from
us too, returning false for indirect DEL_SUBNET.
Fix that by allowing and ignoring indirect DEL_SUBNET in tunnelserver
mode.
Also rearranged the function a bit, to match add_subnet_h() (in
particular, syntax-check everything first, see if we've seen this
request before).
And also fix some comments.
* format 'not supported on this platform' error message
Format it in a similar way in all places, to make translation happier.
No functional changes.
* change error messages in droppriv code to match the rest
Change formatting of error messages about failed syscalls
to be the same as in other places in tincd.
Also suggest a change in "$foo not supported on this platform"
message as it's now used more than once.
* bugfix: chdir(/) after chroot
Fix the famous chdir(".") vs chdir("/") after chroot(something).
* bugfix: move mlock to after detach() so it works for child, not parent
mlock()/mlockall() are not persistent across fork(), and it's
done in parent process before daemon() which does fork(). So
basically, current --mlock does nothing useful.
Move mlock() to after detach() so it works for child process
instead of parent.
Also, check if the platform supports mlock right when processing
options (since else we'll have to die after startup, not at
startup, the error message will be in log only).
* bugfix: initialize pid (as read from pidfile) to zero
If we didn't read any number from a pid file, we'll return
an unitialized variable to the caller, and it will treat
that garbage as a pid of a process (possible to kill).
Fix that.
* Implement privilege dropping
Add two options, -R/--chroot and -U/--user=user, to chroot to the
config directory (where tinc.conf is located) and to perform
setuid to the user specified, after all the initialization is done.
What's left is handling of pid file since we can't remove it anymore.
* Rename setup_network_connections() and split out try_outgoing_connections()
In preparation of chroot/setuid operations, split out call to
try_outgoing_connections() from setup_network_connections()
(which was the last call in setup_network_connections()).
This is because dropping privileges should be done in-between
setup_network_connections() and try_outgoing_connections().
This patch renames setup_network_connections() to setup_network()
and moves call to try_outgoing_connections() into main routine.
No functional changes.
* Handle UDP packets from different and ports than advertised.
Previously, tinc used a fixed address and port for each node for UDP packet
exchange. The port was the one advertised by that node as its listening port.
However, due to NAT the port might be different. Now, tinc sends a different
session key to each node. This way, the sending node can be determined from
incoming packets by checking the MAC against all session keys. If a match is
found, the address and port for that node are updated.
* Use a simple Random Early Drop algorithm in send_tcppacket().
* Disable PMTUDiscovery in switch and hub modes.
In switch and hub modes, tinc does not generate ICMP packets in response to
packets that are larger than the path MTU. However, if PMTUDiscovery is
enabled, the IP_MTU_DISCOVER and IPV6_MTU_DISCOVER option is set on the UDP
sockets, which causes all UDP packets to be sent with the DF bit set, causing
large packets to be dropped, even if they would otherwise be routed fine.
* Update THANKS and copyright information.
* Allow weight to be assigned to Subnets.
Tinc allows multiple nodes to own the same Subnet, but did not have a sensible
way to decide which one to send packets to. Tinc also did not check the
reachability of nodes when deciding where to route packets to, so it would not
automatically fail over to a reachable node.
Tinc now assigns a weight to each Subnet. The default weight is 10, with lower
weights having higher priority. The Subnets are now internally sorted in the
same way as the kernel's routing table, and the Subnets are search linearly,
skipping those of unreachable nodes. A small cache of recently used addresses
is used to speed up the lookup functions.
* Enable PMTUDiscovery only if BOTH sides wants it.
Don't enable PMTUDiscovery if at least one side does not support it.
Before it was enabled if at least one side supported it, now both are required.
* Handle neighbor solicitation requests without link layer addresses.
Apparently FreeBSD likes to send out neighbor solicitation requests, even on a
tun interface where this is completely pointless. These requests do not have an
option header containing a link layer address, so the proxy-neighborsol code
was treating these requests as invalid. We now handle such requests, and send
back equally pointless replies, also without a link layer address. This seems
to satisfy FreeBSD.
* Allow tunnelserver to work with clients that have other peers.
In TunnelServer mode, tinc server disconnects any client if it announces
indirect subnets -- subnets that are not theirs (e.g. subnets for nodes
the CLIENT has connections now, even if those nodes are known to the server
too). Fix that by ignoring such (indirect) announces instead.
While we're at it, move check for such indirect subnet registration to
before allocating new node structure, as in TunnelServer mode we don't
really need to know that other node.
* Disable old RSA keys when generating new ones.
When generating an RSA keypair, the new public and private keys are appended to
files. However, when OpenSSL reads keys it only reads the first in a file, not
the last. Instead of printing an easily ignored warning, tinc now disables old
keys when appending new ones.
* Validate Name before using it in a filename when generating a keypair.
* Allow reading config files with CRLF endings on Unix systems.
* Remove unused definitions from net.h.
* Use a global list to track outgoing connections.
Previously an outgoing_t was maintained for each outgoing connection,
but the pointer to it was either stored in a connection_t or in an event_t.
This made it very hard to keep track of and to clean up.
Now a list is created when tinc starts and reads all the ConnectTo variables,
and which is recreated when tinc receives a HUP signal.
* Add missing cleanup functions in close_network_connections().
* Change flush_events() to expire_events().
The former function made a totally bogus shallow copy of the event_tree, called
the handler of each event and then deleted the whole tree. This should've
caused tinc to crash when an ALARM signal was sent more than once, but for some
reason it didn't. It also behaved incorrectly when a handler added a new event.
The new function just moves the expiration time of all events to the past.
* Move free()s at the end om main() to the proper destructor functions.
* Only send packets via UDP if UDP communication is possible.
When no session key is known for a node, or when it is doing PMTU discovery but
no MTU probes have returned yet, packets are sent via TCP. Some logic is added
to make sure intermediate nodes continue forwarding via TCP. The per-node
packet queue is now no longer necessary and has been removed.
* Consistently allocate device and iface variables on the heap.
This fixes a segfault when no Device has been specified and tinc exits, and it
would try to free() a static string. Thanks to Borg for spottin.
* Update documentation for git.
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