Commit Graph

10 Commits

Author SHA1 Message Date
Robert Quattlebaum
f145c17039 core/net/resolv: IPv6 and mDNS ("Bonjour") support. Major refactor.
This patch updates the DNS resolver to support IPv6 and introduces an
improved API for looking up DNS entries. This patch also adds optional
support for mDNS lookups and responses to the DNS resolver.

Here is a quick summary of the changes:

 * Added support for IPv6 lookups.
 * DNS queries now honor record expiration.
 * Added support for mDNS, compatible with "Bonjour".
 * Implemented a new lookup api, `resolv_lookup2()`, which provides
   more information about the state of the record(error, expired,
   looking-up, etc.).

About mDNS/Bonjour Support
--------------------------

This patch adds basic support for mDNS/Bonjour, which allows you to
refer to the name of a device instead of its IP address. This is
incredibly convenient for IPv6 addresses because they tend to be very
long and difficult to remember. It is especially important for
link-local IPv6 addresses, since not all programs support the '%'
notation for indicating a network interface (required on systems with
more than one network interface to disambiguate).

In other words, instead of typing in this:

 * `http://[fe80::58dc:d7ed:a644:628f%en1]/`

You can type this instead:

 * `http://contiki.local/`

Huge improvement, no?

The convenience extends beyond that: this mechanism can be used for
nodes to talk to each other based on their human-readable names instead
of their IPv6 addresses. So instead of a switch on
`aaaa::58dc:d7ed:a644:628f` triggering an actuator on
`aaaa::ed26:19c1:4bd2:f95b`, `light-switch.local` can trigger the
actuator on `living-room-lights.local`.

What you need to do to be able to look up `.local` names on your
workstation depends on a few factors:

 * Your machine needs to be able to send and receive multicast packets
   to and from the LoWPAN. You can do this easily with the Jackdaw
   firmware on an RZUSBStick. If you have a border router, you will need
   it to bridge the mDNS multicast packets across the border.

 * If you are using a Mac, you win. All Apple devices support mDNS
   lookups.

 * If you are using Windows, you can install Apple's Bonjour for Windows
   package. (This may be already installed on your machine if you have
   installed iTunes) After you install this you can easily do `.local`
   lookups.

 * If you are using a Unix machine, you can install Avahi.

The default hostname is set to `contiki.local.`. You can change the
hostname programmatically by calling `resolv_set_hostname()`. You can
change the default hostname by changing `CONTIKI_CONF_DEFAULT_HOSTNAME`.

You may disable mDNS support by setting `RESOLV_CONF_SUPPORTS_MDNS` to
`0`.

---------------------------------

core/net/resolv: `resolv_lookup2()` -> `resolv_lookup()`

Note that this patch should fix several `resolv_lookup()` bugs
that already existed. There were many cases where `resolv_lookup()`
was being called and the IP address ignored, but later code
assumed that the IP address had been fetched... ANYWAY, those
should be fixed now.

---------------------------------

examples/udp-ipv6: Updated client to use MDNS to lookup the server.

Also updated the Cooja regression test simulation.
2013-03-10 11:40:08 -07:00
Adam Dunkels
944537fccf Removed all old RCS tags in the Contiki source tree. Those RCS tags are not used any more, as we are now using git to manage the Contiki source tree 2012-10-26 15:54:49 +02:00
Adam Dunkels
d28ea5e915 Compile with SMALL=1 to make binary fit in memory 2011-09-06 01:59:01 +02:00
adamdunkels
511389ae09 Have to remove PLATFORM_BUILD from the makefile to make code fit into memory 2010-02-04 07:53:52 +00:00
adamdunkels
b5ea3e297b Readded the shell file module so that the nightly test works 2010-02-03 20:42:23 +00:00
adamdunkels
53d93eb83f Removed Coffee to reduces the size to make it compile successfully 2010-02-02 19:41:49 +00:00
joxe
3b97f72c0c added makefile with saved target 2009-06-23 21:03:13 +00:00
adamdunkels
61d33173a3 Renamed the serial module to serial-line 2009-03-18 07:20:18 +00:00
fros4943
659c7e7311 added webserver-nogui source and WITH_NULLMAC to example code (too large otherwise) 2009-03-03 17:25:33 +00:00
fros4943
008d4ba33f sky example running both webserver and serial shell (overrides default slip handler) 2009-01-15 13:18:19 +00:00