IceScan is a free open source network analyzing and security auditing tool for Unix-like and Windows operating systems. It uses libpcap, a packet capture and filtering library. Main features is active and passive scanning with various technics (for example, TCP SYN, IP protocol, TCP XMAS and more), passive OS detection and scripting engine. Get it from https://sourceforge.net/project/showfiles.php?group_id=185109 or from CVS! Windows binary release will come in next few days.
We're lack of active developers, so any help in development would be very good.
ChangeLog for IceScan v. 0.0.7rc1:
* fixed minor bugs with running on Win32.
+ UDP scan and ping completely rewritten.
+ TCP and UDP scan now independent and can be run in parallel.
* ICMP PortUnreach messages now handling in TCP/UDP raw scans.
+ OpenBSD port done.
+ first attempt to create script engine.
* fixed ACK scan.
+ added group results by host in output.
+ added detecting if target is localhost.
+ boosted localhost scan, fixed filtered ports on localhost.
+ added passive OS fingerprinting.
+ added detecting MTU, remote line type and remote system uptime when possible.
* fixed routing mask operation.
+ Ctrl-C signal correct handle in passive scan mode.
* list and "no" scans work correct now.
* fixed printing reverse hostname (domain name) in several places.
+ parallel DNS-resolver for resolving ip/revnames at active scan phase.
+ --system-dns ans --dns-servers options.
+ own DNS-resolver for resolving names/revnames at passive scan phase.
* fixed cpcapreader::read_rawpacket segfault on BIG packets.
* system dns servers extraction from resolv.conf(*nix) or registry.
* added --tcp-options: set tcp options at raw scan.
* added --open option: show only open(or possibly open) ports.
* fixed ARP discovery.
* fixed "No Scan" (S0) output.
+ added additional hosts debug stats.
+ added "all-hosts" congestion window.
+ added -w (dump recieved packets to tcpdump file) option.
+ added --pcap-filter (set the pcap filter) option.
* manpage fixes