NMap，也就是Network Mapper，是Linux下的网络扫描和嗅探工具包。其基本功能有三个，一是探测一组主机是否在线；其次是扫描 主机端口，嗅探所提供的网络服务；还可以推断主机所用的操作系统 。Nmap可用于扫描仅有两个节点的LAN，直至500个节点以上的网络。Nmap 还允许用户定制扫描技巧。通常，一个简单的使用ICMP协议的ping操 作可以满足一般需求；也可以深入探测UDP或者TCP端口，直至主机所 使用的操作系统；还可以将所有探测结果记录到各种格式的日志中， 供进一步分析操作。
o [Zenmap] Fixed a hang that would occur on Mac OS X 10.7. A symptom
of the hang was this message in the system console:
"Couldn t recognize the image file format for file
o [Zenmap] Fixed a crash that happened when activating the host filter.
File "zenmapCoreSearchResult.pyo", line 155, in match_os
o Fixed an error that occurred when scanning certain addresses like
192.168.0.0 on Windows XP:
get_srcaddr: can t connect socket: The requested address is not valid in its context.
nexthost: failed to determine route to 10.80.0.0
o Fixed a bug that caused Nmap to fail to find any network interface when
at least one of them is in the monitor mode. The fix was to define the
ARP_HRD_IEEE80211_RADIOTAP 802.11 radiotap header identifier in the
libdnet-stripped code. Network interfaces that are in this mode are used
by radiotap for 802.11 frame injection and reception. The bug was
reported by Tom Eichstaedt and Henri Doreau.
[Djalal Harouni, Henri Doreau]
o Fixed the greppable output of hosts that time-out (when --host-timeout was
used and the host timed-out after something was received from that host).
This issue was reported by Matthew Morgan. [jah]
o [Zenmap] Updated the version of Python used to build the Windows
release from 2.7.1 to 2.7.3 to remove a false-positive security
alarm flagged by tools such as Secunia PSI. There was a minor
vulnerability in certain Python27.dll web functionality (which Nmap
doesn t use anyway) and Secunia was flagging all software which
includes that version of Python27.dll. This update should prevent
the false alarm.
Nmap ( Network Mapper ) is a free and open source (license) utility for network exploration or security auditing. Many systems and network administrators also find it useful for tasks such as network inventory, managing service upgrade schedules, and monitoring host or service uptime. Nmap uses raw IP packets in novel ways to determine what hosts are available on the network, what services (application name and version) those hosts are offering, what operating systems (and OS versions) they are running, what type of packet filters/firewalls are in use, and dozens of other characteristics. It was designed to rapidly scan large networks, but works fine against single hosts. Nmap runs on all major computer operating systems, and official binary packages are available for Linux, Windows, and Mac OS X. In addition to the classic command-line Nmap executable, the Nmap suite includes an advanced GUI and results viewer (Zenmap), a flexible data transfer, redirection, and debugging tool (Ncat), a utility for comparing scan results (Ndiff), and a packet generation and response analysis tool (Nping).