flag) is received in response. This can be due to an extremely rare TCP feature
known as a simultaneous open or split handshake connection.
see http://nmap.org/misc/split-handshake.pdf
Added a reason code: ER_SYN and associated reason string: "split-handshake-syn".
changes. The first is that Port objects don't allocate memory for
service and RPC results unless that information is set. This reduces the
size of a bare Port from 92 to 40 bytes on my machine. The second change
is that PortList now has the notion of a "default port state," which is
the state of any ports that didn't receive a response. These ports don't
need an allocated Port object, which saves a lot of memory in scans
where most ports didn't get a response.
a layer 4 protocol used mostly for telephony related applications.
This brings the following new features:
o SCTP INIT chunk port scan (-sY): open ports return an INIT-ACK
chunk, closed ones an ABORT chunk. This is the SCTP equivalent
of a TCP SYN stealth scan.
o SCTP COOKIE-ECHO chunk port scan (-sZ): open ports are silent,
closed ports return an ABORT chunk.
o SCTP INIT chunk ping probes (-PY): host discovery using SCTP
INIT chunk packets.
o SCTP-specific IP protocol scan (-sO -p sctp).
o SCTP-specific traceroute support (--traceroute).
o The ability to use the deprecated Adler32 algorithm as specified
in RFC 2960 instead of CRC32C from RFC 4960 (--adler32).
o 42 well-known SCTP ports were added to the nmap-services file.
Part of the work on SCTP support was kindly sponsored by
Compass Security AG, Switzerland. [Daniel Roethlisberger]
