安裝

yum install -y ngrep		
		

幫助信息

		
# ngrep -help
usage: ngrep <-hNXViwqpevxlDtTRM> <-IO pcap_dump> <-n num> <-d dev> <-A num>
             <-s snaplen> <-S limitlen> <-W normal|byline|single|none> <-c cols>
             <-P char> <-F file> <match expression> <bpf filter>
   -h  is help/usage
   -V  is version information
   -q  is be quiet (don't print packet reception hash marks)
   -e  is show empty packets
   -i  is ignore case
   -v  is invert match
   -R  is don't do privilege revocation logic
   -x  is print in alternate hexdump format
   -X  is interpret match expression as hexadecimal
   -w  is word-regex (expression must match as a word)
   -p  is don't go into promiscuous mode
   -l  is make stdout line buffered
   -D  is replay pcap_dumps with their recorded time intervals
   -t  is print timestamp every time a packet is matched
   -T  is print delta timestamp every time a packet is matched
         specify twice for delta from first match
   -M  is don't do multi-line match (do single-line match instead)
   -I  is read packet stream from pcap format file pcap_dump
   -O  is dump matched packets in pcap format to pcap_dump
   -n  is look at only num packets
   -A  is dump num packets after a match
   -s  is set the bpf caplen
   -S  is set the limitlen on matched packets
   -W  is set the dump format (normal, byline, single, none)
   -c  is force the column width to the specified size
   -P  is set the non-printable display char to what is specified
   -F  is read the bpf filter from the specified file
   -N  is show sub protocol number
   -d  is use specified device instead of the pcap default
		
		

# ngrep -q GET -d eth1 port 80
# ngrep -q POST -d eth1 port 80
# ngrep -q /news/111.html -d eth1 port 80
# ngrep -q User-Agent -d eth1 port 80
# ngrep -q Safari -d eth1 port 80
			

# ngrep -q HELO -d enp2s0 port 25mp
interface: enp2s0 (173.254.223.0/255.255.255.192)
filter: ( port 25 ) and (ip or ip6)
match: HELO

T 47.90.44.87:39023 -> 173.254.223.53:25 [AP]
  HELO localhost..                                                                                                                                                                                                                       

T 47.90.44.87:39024 -> 173.254.223.53:25 [AP]
  HELO localhost..                                                                                                                                                                                                                       

T 47.90.44.87:39025 -> 173.254.223.53:25 [AP]
  HELO localhost..
			

# ngrep -d eth0
# ngrep -d enp2s0