DOKK / manpages / debian 12 / dsniff / dsniff.8.en
DSNIFF(8) System Manager's Manual DSNIFF(8)

dsniff - password sniffer



dsniff [-c] [-d] [-m] [-n]
    [-i interface | -p pcapfile] [-s
    snaplen] [-f services] [-t
    trigger[,...]]] [-r|-w savefile]
    [expression]










dsniff is a password sniffer which handles FTP, Telnet,
    SMTP, HTTP, POP, poppass, NNTP, IMAP, SNMP, LDAP, Rlogin, RIP, OSPF, PPTP
    MS-CHAP, NFS, VRRP, YP/NIS, SOCKS, X11, CVS, IRC, AIM, ICQ, Napster,
    PostgreSQL, Meeting Maker, Citrix ICA, Symantec pcAnywhere, NAI Sniffer,
    Microsoft SMB, Oracle SQL*Net, Sybase and Microsoft SQL protocols.


dsniff automatically detects and minimally parses each
    application protocol, only saving the interesting bits, and uses Berkeley DB
    as its output file format, only logging unique authentication attempts. Full
    TCP/IP reassembly is provided by libnids(3).


I wrote dsniff with honest intentions - to audit my own
    network, and to demonstrate the insecurity of cleartext network protocols.
    Please do not abuse this software.









  

  
Perform half-duplex TCP stream reassembly, to handle asymmetrically routed
      traffic (such as when using arpspoof(8) to intercept client traffic bound
      for the local gateway).

  

  
Enable debugging mode.

  

  
Enable automatic protocol detection.

  

  
Do not resolve IP addresses to hostnames.

  

  
Specify the interface to listen on.

  

  
Rather than processing the contents of packets observed upon the network
      process the given PCAP capture file.

  

  
Analyze at most the first snaplen bytes of each TCP connection,
      rather than the default of 1024.

  

  
Load triggers from a services file.

  

  
Load triggers from a comma-separated list, specified as
      port/proto=service (e.g. 80/tcp=http).

  

  
Read sniffed sessions from a savefile created with the -w
      option.

  

  
Write sniffed sessions to savefile rather than parsing and printing
      them out.

  

  
Specify a tcpdump(8) filter expression to select traffic to sniff.




On a hangup signal dsniff will dump its current trigger
    table to dsniff.services.









  
/usr/share/dsniff/dsniff.services

  
Default trigger table

  
/usr/share/dsniff/dsniff.magic

  
Network protocol magic










arpspoof(8), libnids(3), services(5), magic(5)








Dug Song <dugsong@monkey.org>








dsniff's automatic protocol detection feature is based on
    the classic file(1) command by Ian Darwin, and shares its historical
    limitations and bugs.