ipgrab - A Verbose Packet Sniffer

       Michael S. Borella
       http://www.borella.net/mike/mike@borella.net

                                                  07 March 2007                                        IPGRAB(8)

ipgrab  reads  and  parses  packets  from  the link layer through the application layer, dumping explicit
       header information along the way.  It is a lot like tcpdump except that it  prints  almost  every  header
       field.

   Options-a     Do not display application layer data.

       -b     Buffer standard output. Useful when you're redirecting output to a file.

       -ccnt, --countcnt
              Terminate after receiving cnt packets.

       -Cproto, --CCPproto
              Assume a particular CCP protocol, such as MPPC. MPPC is the only one supported as yet.

       -d     Dump  extra  padding  in  packets.  For  example,  according to an IP header, the packet ends at a
              certain point, but the link layer may have  padded  it  beyond  that.  This  option  displays  the
              padding. Not valid in minimal mode.

       -h,--help
              Display usage screen with a brief description of the command line options.

       -iif, --interfaceif
              Makes  ipgrab  listen  to  packets  on  interface  if, e.g., eth0. If this option is not used, the
              default interface will be assumed.

       -l     Don't display link-layer headers. The following protocols are considered to be  link  layer:  ARP,
              CHAP, Ethernet, IPCP, LCP, LLC, Loopback, PPP, PPPoE, Raw, Slip.

       -m     Minimal mode output. When operating in this mode, ipgrab displays only brief header information.

       -n     Don't  display  network-layer headers. The following protocols are considered to be network layer:
              AH, ESP, GRE, ICMP, ICMPv6, IGMP, IP, IPv6, IPX, IPXRIP.

       -Pstring
              Initiate a dynamic  port  mapping.  This  option  must  be  followed  by  a  string  of  the  form
              `<protocol>=<port>', such as `http=8080'.

       -p     Dump  packet  payloads  beyond  what  IPgrab  parses.  In  other words, if IPgrab does not parse a
              particular application, this option will dump application data in hex and text format.

       -r FILE
              Read packets from a file, rather than an interface. The file should be created  in  "raw"  format,
              such as with '-w' option.

       -T     Do not display timestamps in minimal mode.

       -t     Don't  display  transport  layer  headers.  The following protocols are considered to be transport
              layer: SPX, TCP, UDP.

       -v,--version
              Display version number and then quit.

       -w FILE
              Write the raw packets to a file, rather than the screen. The packets will not be parsed. The  file
              can be read with the '-r' option.

       -x     Hex  dump  mode. After processing each layer, dump out the contents of that layer in hex and text.
              Only valid in main mode.

       expr   Berkeley packet filter expression.  See tcpdump(8) man page for details and examples.

       ipgrab - A Verbose Packet Sniffer

       Requires libpcap version 0.3 or greater to be installed.

tcpdump(8)

ipgrab [ -ablmnPprTtwx ] [ -c cnt ] [ -i if ] [ expr ]