Quando si tratta di sicurezza informatica è cosa buona e giusta utilizzare le ultime versioni dei programmi che utilizziamo per effettuare i test, uno di questi è Nmap (Networking Mapper), il più famoso e secondo me il miglior port scanner (e non solo…) al mondo.

Nmap è scritto fondamentalmente in C ed in C++, ed ha numerosi frontend che onestamente odio con tutto il cuore.

E’ nato nel 1997 dal famoso hacker tedesco Fyodor ed il suo sviluppo è ancora in corso.

In questo articolo vedremo come compilare da sorgente l’ultima versione stabile (attualmente la 7.40) su Debian Jessie.

Innanzitutto soddisfiamo le sue dipendenze digitando:

# apt-get install gcc g++ make

Andiamo sul sulla pagina di download del sito di nmap per vedere qual’è l’ultima versione: https://nmap.org/download.html

Al momento in cui scrivo è la 7.40, scarichiamo quindi il suo codice sorgente:

$ aria2c https://nmap.org/dist/nmap-7.40.tar.bz2

Decomprimiamolo ed entriamo nella cartella generata:

$ tar -xvjf nmap-7.40.tar.bz2 && cd nmap-7.40

Adesso configuriamo l’installer in modo da generarci il Makefile per la compilazione:

$ ./configure

Se la configurazione è andata a buon fine vedremo un output simile a questo:

            .       .
            \`-"'"-'/
             } 6 6 {
            ==. Y ,==
              /^^^\  .
             /     \  )  Ncat: A modern interpretation of classic Netcat
            (  )-(  )/
            -""---""---   /
           /   Ncat    \_/
          (     ____
           \_.=|____E
Configuration complete.

                    ___.-------.___
                _.-' ___.--;--.___ `-._
             .-' _.-'  /  .+.  \  `-._ `-.
           .' .-'      |-|-o-|-|      `-. `.
          (_  _)
            `--._``-..__`._|_.'__..-''_.--'
                  ``--._________.--''
   ____  _____  ____    ____       _       _______
  |_   \|_   _||_   \  /   _|     / \     |_   __ \
    |   \ | |    |   \/   |      / _ \      | |__) |
    | |\ \| |    | |\  /| |     / ___ \     |  ___/
   _| |_\   |_  _| |_\/_| |_  _/ /   \ \_  _| |_
  |_____|\____||_____||_____||____| |____||_____|

  NMAP IS A POWERFUL TOOL -- USE CAREFULLY AND RESPONSIBLY
Configured with: ndiff zenmap nping openssl lua ncat
Configured without: localdirs nmap-update
Type make (or gmake on some *BSD machines) to compile.

Ci dice anche di lanciare il make, ed infatti è quello che faremo:

$ make

Se non ci sono errori possiamo procedere alla sua installazione con il comando:

# make install

Se tutto è andato a buon fine dovremmo vedere un output simile a questo:

NPING SUCCESSFULLY INSTALLED
make[1]: uscita dalla directory "/home/davenull/nmap-7.40/nping"
NMAP SUCCESSFULLY INSTALLED

Per vedere se funziona basta lanciarlo senza parametri:

# nmap

E dovremmo ricevere l’help come output, eccolo qui:

Nmap 7.40 ( https://nmap.org )
Usage: nmap [Scan Type(s)] [Options] {target specification}
TARGET SPECIFICATION:
  Can pass hostnames, IP addresses, networks, etc.
  Ex: scanme.nmap.org, microsoft.com/24, 192.168.0.1; 10.0.0-255.1-254
  -iL : Input from list of hosts/networks
  -iR : Choose random targets
  --exclude : Exclude hosts/networks
  --excludefile : Exclude list from file
HOST DISCOVERY:
  -sL: List Scan - simply list targets to scan
  -sn: Ping Scan - disable port scan
  -Pn: Treat all hosts as online -- skip host discovery
  -PS/PA/PU/PY[portlist]: TCP SYN/ACK, UDP or SCTP discovery to given ports
  -PE/PP/PM: ICMP echo, timestamp, and netmask request discovery probes
  -PO[protocol list]: IP Protocol Ping
  -n/-R: Never do DNS resolution/Always resolve [default: sometimes]
  --dns-servers : Specify custom DNS servers
  --system-dns: Use OS's DNS resolver
  --traceroute: Trace hop path to each host
SCAN TECHNIQUES:
  -sS/sT/sA/sW/sM: TCP SYN/Connect()/ACK/Window/Maimon scans
  -sU: UDP Scan
  -sN/sF/sX: TCP Null, FIN, and Xmas scans
  --scanflags : Customize TCP scan flags
  -sI : Idle scan
  -sY/sZ: SCTP INIT/COOKIE-ECHO scans
  -sO: IP protocol scan
  -b : FTP bounce scan
PORT SPECIFICATION AND SCAN ORDER:
  -p : Only scan specified ports
    Ex: -p22; -p1-65535; -p U:53,111,137,T:21-25,80,139,8080,S:9
  --exclude-ports : Exclude the specified ports from scanning
  -F: Fast mode - Scan fewer ports than the default scan
  -r: Scan ports consecutively - don't randomize
  --top-ports : Scan  most common ports
  --port-ratio : Scan ports more common than 
SERVICE/VERSION DETECTION:
  -sV: Probe open ports to determine service/version info
  --version-intensity : Set from 0 (light) to 9 (try all probes)
  --version-light: Limit to most likely probes (intensity 2)
  --version-all: Try every single probe (intensity 9)
  --version-trace: Show detailed version scan activity (for debugging)
SCRIPT SCAN:
  -sC: equivalent to --script=default
  --script=:  is a comma separated list of
           directories, script-files or script-categories
  --script-args=: provide arguments to scripts
  --script-args-file=filename: provide NSE script args in a file
  --script-trace: Show all data sent and received
  --script-updatedb: Update the script database.
  --script-help=: Show help about scripts.
            is a comma-separated list of script-files or
           script-categories.
OS DETECTION:
  -O: Enable OS detection
  --osscan-limit: Limit OS detection to promising targets
  --osscan-guess: Guess OS more aggressively
TIMING AND PERFORMANCE:
  Options which take  are in seconds, or append 'ms' (milliseconds),
  's' (seconds), 'm' (minutes), or 'h' (hours) to the value (e.g. 30m).
  -T: Set timing template (higher is faster)
  --min-hostgroup/max-hostgroup : Parallel host scan group sizes
  --min-parallelism/max-parallelism : Probe parallelization
  --min-rtt-timeout/max-rtt-timeout/initial-rtt-timeout : Specifies
      probe round trip time.
  --max-retries : Caps number of port scan probe retransmissions.
  --host-timeout : Give up on target after this long
  --scan-delay/--max-scan-delay : Adjust delay between probes
  --min-rate : Send packets no slower than  per second
  --max-rate : Send packets no faster than  per second
FIREWALL/IDS EVASION AND SPOOFING:
  -f; --mtu : fragment packets (optionally w/given MTU)
  -D : Cloak a scan with decoys
  -S : Spoof source address
  -e : Use specified interface
  -g/--source-port : Use given port number
  --proxies : Relay connections through HTTP/SOCKS4 proxies
  --data : Append a custom payload to sent packets
  --data-string : Append a custom ASCII string to sent packets
  --data-length : Append random data to sent packets
  --ip-options : Send packets with specified ip options
  --ttl : Set IP time-to-live field
  --spoof-mac : Spoof your MAC address
  --badsum: Send packets with a bogus TCP/UDP/SCTP checksum
OUTPUT:
  -oN/-oX/-oS/-oG : Output scan in normal, XML, s|<rIpt kIddi3,
     and Grepable format, respectively, to the given filename.
  -oA : Output in the three major formats at once
  -v: Increase verbosity level (use -vv or more for greater effect)
  -d: Increase debugging level (use -dd or more for greater effect)
  --reason: Display the reason a port is in a particular state
  --open: Only show open (or possibly open) ports
  --packet-trace: Show all packets sent and received
  --iflist: Print host interfaces and routes (for debugging)
  --append-output: Append to rather than clobber specified output files
  --resume : Resume an aborted scan
  --stylesheet : XSL stylesheet to transform XML output to HTML
  --webxml: Reference stylesheet from Nmap.Org for more portable XML
  --no-stylesheet: Prevent associating of XSL stylesheet w/XML output
MISC:
  -6: Enable IPv6 scanning
  -A: Enable OS detection, version detection, script scanning, and traceroute
  --datadir : Specify custom Nmap data file location
  --send-eth/--send-ip: Send using raw ethernet frames or IP packets
  --privileged: Assume that the user is fully privileged
  --unprivileged: Assume the user lacks raw socket privileges
  -V: Print version number
  -h: Print this help summary page.
EXAMPLES:
  nmap -v -A scanme.nmap.org
  nmap -v -sn 192.168.0.0/16 10.0.0.0/8
  nmap -v -iR 10000 -Pn -p 80
SEE THE MAN PAGE (https://nmap.org/book/man.html) FOR MORE OPTIONS AND EXAMPLES

Nei prossimi articoli vedremo come utilizzarlo al meglio.