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David Girault a2498898b0 mdns: increase mDNS output packet size
When more than one service (just 2) need to be probed for conflict, generation
of the probe packet fail because pbuf is too small!

So OUTPACKET_SIZE renamed to MDNS_OUTPUT_PACKET_SIZE and moved to mdns_opts.h
to allow configuration. Default configuration raise it to 1450 to have enough
space when MDNS_MAX_SERVICES > 1 else it remain 512.

Extract from RFC 6762, chapter 17, Multicast DNS Message Size:

   The 1987 DNS specification [RFC1035] restricts DNS messages carried
   by UDP to no more than 512 bytes (not counting the IP or UDP
   headers).  For UDP packets carried over the wide-area Internet in
   1987, this was appropriate.  For link-local multicast packets on
   today's networks, there is no reason to retain this restriction.
   Given that the packets are by definition link-local, there are no
   Path MTU issues to consider.

   Multicast DNS messages carried by UDP may be up to the IP MTU of the
   physical interface, less the space required for the IP header (20
   bytes for IPv4; 40 bytes for IPv6) and the UDP header (8 bytes).

Signed-off-by: Simon Goldschmidt <goldsimon@gmx.de>
2019-12-11 20:11:13 +01:00
.vscode VS code workspace: add unit tests 2018-10-27 22:35:54 +02:00
contrib default_netif.c: add missing include 2019-12-11 19:49:26 +01:00
doc mdns: defined the service slot id as unsigned rather than signed. 2019-04-30 12:33:22 +02:00
src mdns: increase mDNS output packet size 2019-12-11 20:11:13 +01:00
test fuzz: adapt to changes in mdns 2019-12-11 19:50:50 +01:00
.gitattributes
.gitignore Update .gitignore for latest VSCode 2019-03-20 20:50:35 +01:00
.travis.yml Try to get ninja-build running on Travis 2018-10-18 11:05:07 +02:00
BUILDING Improve build system documentation 2018-10-21 20:30:48 +02:00
CHANGELOG sync CHANGELOG after releasing 2.1.1 2018-11-09 17:23:17 +01:00
CMakeLists.txt List supported build types in top-level CMakeLists.txt 2018-11-26 09:26:37 +01:00
COPYING
FEATURES Add ACD to several documents 2018-10-04 21:13:32 +02:00
FILES Add contrib subdir to FILES 2018-10-02 13:15:41 +02:00
README README: put wiki after mailing lists (it's not that good...) 2018-10-17 20:27:00 +02:00
travis.sh More cleanups to travis.sh - run all test even if some fail 2019-02-03 09:36:44 +01:00
UPGRADING Documentation improvements for 2.1.0 (mainly altcp/altcp_tls) 2018-09-24 22:44:32 +02:00

INTRODUCTION

lwIP is a small independent implementation of the TCP/IP protocol suite.

The focus of the lwIP TCP/IP implementation is to reduce the RAM usage
while still having a full scale TCP. This making lwIP suitable for use
in embedded systems with tens of kilobytes of free RAM and room for
around 40 kilobytes of code ROM.

lwIP was originally developed by Adam Dunkels at the Computer and Networks
Architectures (CNA) lab at the Swedish Institute of Computer Science (SICS)
and is now developed and maintained by a worldwide network of developers.

FEATURES

  * IP (Internet Protocol, IPv4 and IPv6) including packet forwarding over
    multiple network interfaces
  * ICMP (Internet Control Message Protocol) for network maintenance and debugging
  * IGMP (Internet Group Management Protocol) for multicast traffic management
  * MLD (Multicast listener discovery for IPv6). Aims to be compliant with
    RFC 2710. No support for MLDv2
  * ND (Neighbor discovery and stateless address autoconfiguration for IPv6).
    Aims to be compliant with RFC 4861 (Neighbor discovery) and RFC 4862
    (Address autoconfiguration)
  * DHCP, AutoIP/APIPA (Zeroconf), ACD (Address Conflict Detection)
    and (stateless) DHCPv6
  * UDP (User Datagram Protocol) including experimental UDP-lite extensions
  * TCP (Transmission Control Protocol) with congestion control, RTT estimation
    fast recovery/fast retransmit and sending SACKs
  * raw/native API for enhanced performance
  * Optional Berkeley-like socket API
  * TLS: optional layered TCP ("altcp") for nearly transparent TLS for any
    TCP-based protocol (ported to mbedTLS) (see changelog for more info)
  * PPPoS and PPPoE (Point-to-point protocol over Serial/Ethernet)
  * DNS (Domain name resolver incl. mDNS)
  * 6LoWPAN (via IEEE 802.15.4, BLE or ZEP)


APPLICATIONS

  * HTTP server with SSI and CGI (HTTPS via altcp)
  * SNMPv2c agent with MIB compiler (Simple Network Management Protocol), v3 via altcp
  * SNTP (Simple network time protocol)
  * NetBIOS name service responder
  * MDNS (Multicast DNS) responder
  * iPerf server implementation
  * MQTT client (TLS support via altcp)


LICENSE

lwIP is freely available under a BSD license.


DEVELOPMENT

lwIP has grown into an excellent TCP/IP stack for embedded devices,
and developers using the stack often submit bug fixes, improvements,
and additions to the stack to further increase its usefulness.

Development of lwIP is hosted on Savannah, a central point for
software development, maintenance and distribution. Everyone can
help improve lwIP by use of Savannah's interface, Git and the
mailing list. A core team of developers will commit changes to the
Git source tree.

The lwIP TCP/IP stack is maintained in the 'lwip' Git module and
contributions (such as platform ports) are in the 'contrib' Git module.

See doc/savannah.txt for details on Git server access for users and
developers.

The current Git trees are web-browsable:
  http://git.savannah.gnu.org/cgit/lwip.git
  http://git.savannah.gnu.org/cgit/lwip/lwip-contrib.git

Submit patches and bugs via the lwIP project page:
  http://savannah.nongnu.org/projects/lwip/

Continuous integration builds (GCC, clang):
  https://travis-ci.org/lwip-tcpip/lwip


DOCUMENTATION

Self documentation of the source code is regularly extracted from the current
Git sources and is available from this web page:
  http://www.nongnu.org/lwip/

Also, there are mailing lists you can subscribe at
  http://savannah.nongnu.org/mail/?group=lwip
plus searchable archives:
  http://lists.nongnu.org/archive/html/lwip-users/
  http://lists.nongnu.org/archive/html/lwip-devel/

There is a wiki about lwIP at
  http://lwip.wikia.com/wiki/LwIP_Wiki
You might get questions answered there, but unfortunately, it is not as
well maintained as it should be.

lwIP was originally written by Adam Dunkels:
  http://dunkels.com/adam/

Reading Adam's papers, the files in docs/, browsing the source code
documentation and browsing the mailing list archives is a good way to
become familiar with the design of lwIP.

Adam Dunkels <adam@sics.se>
Leon Woestenberg <leon.woestenberg@gmx.net>