NDIFF(1)

NAME
ndiff - find differences between two nmap network scans

SYNOPSIS
 ndiff    [-b|-baseline  <file-or-:tag>]   [-o|-observed  <file-or-:tag>]
          [-op|-output-ports <ocufx>]      [-of|-output-hosts <nmc>]
          [-fmt|-format <terse | minimal | verbose | machine | html | htmle>]

DESCRIPTION
ndiff allows a network administrator or other interested party to easily monitor one or more networks for changes in port states and running services. It achieves this by comparing the results of two nmap scans, one designated the "baseline", the other "observation".

Both baseline and observation are stored in files generated via nmap's -m switch.

OPTIONS

-b <filename-or-:tag>
-baseline <filename-or-:tag>
    Specifies the nmap results to use as the baseline for the comparison. Normally this is the name of an nmap machine-parseable file, but if the parameter starts with a colon (:), it is treated as a key into a data store. See "DATA STORES" below for more information.

    See "SUBSTITUTIONS" below for information about using %-style expansions within filenames and :tags.

-o <filename-or-:tag>
-observed <filename-or-:tag>
    Specifies the nmap results to use as the "observed results" for the comparison. Normally this is the name of an nmap machine-parseable file, but if the parameter starts with a colon (:), it is treated as a key into a data store. See "DATA STORES" below for more information.

    See "SUBSTITUTIONS" below for information about using %-style expansions within filenames and :tags.

-fmt  <terse | minimal | verbose | machine | html | htmle>
-format  <terse | minimal | verbose | machine | html | htmle>
    Specifies the level of detail in the output. "html" causes ndiff to generate an html page, while "htmle" causes ndiff to generate an embeddable html fragment (See ndiff2html).

-op [ocufx]
-output-ports [ocufk]
    Specifies which ports to display when outputting changed hosts. Any combination of the characters [ocufx] may be specified to enable printing of ports that changed to states (in the "observed" scan) as follows:

     o = open
     c = closed
     f = filtered
     x = unfiltered
     k = unknown (wasn't scanned or host wasn't up)

-oh [nmc]
-output-hosts [nmc]
    Specifies which types hosts to display. Any combination of [nmc] may be specified, as follows:

     n = new hosts (in the "observed" scan)
     m = missing hosts ( " " " )
     c = changed hosts ( " " " )

-of <file>
-output-file <file>
    Send the output to the specified file. % substitutions are supported in the filename, see "SUBSTITUTIONS" below.

DATA STORES
Nrun and its related tools can manipulate results in regular nmap-format files, in any user-specified location, or they can handle storing and organizing the data on behalf of the user, through a user-configurable "data store".

Whenever you precede a results tag with a colon (:), the tag will be treated as a unique key into a data store, identifying the results set.

Currently the only supported data store is nmap format files placed in a preconfigured directory. Other types may be added at a later date.

A legal tag may contain any alphanumeric string, plus dash, underscore, and dot. %-style substitutions in the ilk of the "date" command are also supported, allowing a tag to contain date, time, or the local hostname. See "SUBSTITUTIONS" below for more information.

SUBSTITUTIONS
%-style substitutions supported in tags as follows:

%H = hour
%M = minute
%S = second
%D = day of month
%m = month of year (01-12)
%Y = year, four digits
%j = day of year, three digits
%w = day of week (0-6) one digit

Except where noted, the above items are two digits, and local time. All are zero-padded as appropriate.

In addtion-

%F = output of "hostname" on the local machine

BUGS
It's too slow -- approx 3 scanned hosts per second on a Pentium II-300. No support for human-readable hostnames and portnames. Port/protocol output formatting is inconsistent in certain places.

AUTHOR
James Levine <jdl@vinecorp.com>