sisniff

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Ein Netzwerk-Sniffer der für jedes Packet nebst Adresse und Port die lokal verbundene Anwendung und deren PID ermittelt und anzeigt.

Die Standard Sniffer wie tcpdump oder Wireshark zeigen lediglich die Packete über eine Schnittstelle auf.
sisniff hingegen versucht die dazugehörigen Anwendungen zu ermitteln und verknüpft diese mit den jeweiligen Packeten.

Es wird TCP, UDP und ICMP unterstützt, für IPv4 und IPv6.
Der Sniffer akzeptiert Filter wie sie bei tcpdump üblich sind.

Bei HTTP Verbindungen kann ausserdem ein Teil der Payload angezeigt werden.

sisniff Image


Die Option -h gibt eine Argumenteübersicht und listet die verfügbaren Interfaces auf. 

# ./sisniff -h
usage: sisniff [-h] -i {eth0,lo,wlan0} [-n] [-p program|not-program] [-4] [-6] [-pH] [-pHl] [filter]

sisniff V1.00
2017-2019 by sigi <https://wiki.zweiernet.ch/wiki/sisniff>

positional arguments:
  filter                Filter (BPF syntax) on top of IP (in dbl-quotes "...")

optional arguments:
  -h, --help            show this help message and exit
  -i {eth0,lo,wlan0}    Interface (required)
  -n                    Do not resolve IP-Addresses
  -p program|not-program
                        Filter by program name ([not-] negates)
  -4                    Only IPv4
  -6                    Only IPv6
  -pH                   Show HTTP Payload
  -pHl                  Show HTTP Payload, long output

Downloads der aktuellen Version
Source: https://git.zweiernet.ch/sigi/sisniff/raw/master/sisniff
gzipped: https://git.zweiernet.ch/sigi/sisniff/archive/master.tar.gz
Git Projektseite: https://git.zweiernet.ch/sigi/sisniff


i

Da sisniff auf der Scapy sniff()-Funktion aufsetzt, wird Scapy > 2.x benötigt:

Unter Debian/Ubuntu: apt-get install scapy
pip/pip3: pip install scapy
Andere: http://www.secdev.org/projects/scapy/


Python Code: 

#!/usr/bin/env python
 
# (c) 2017-2019 by Siegrist(SystemLoesungen) <PSS@ZweierNet.ch>
#
# All Rights reserved.
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License as
# published by the Free Software Foundation.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
 
from scapy.all import *
import pwd
import os
import re
import glob
import sys
import string
import fcntl
import struct
import argparse
if sys.version_info.major == 2:
    import commands as subprocess
elif sys.version_info.major == 3:
    import subprocess
 
def _to_str(inp):
    if sys.version_info.major == 2:
        return inp
    else:
        return "".join( chr(x) for x in inp)
 
 
VERSION = "1.00"
 
PROC_TCP4 = "/proc/net/tcp"
PROC_UDP4 = "/proc/net/udp"
PROC_ICMP4 = "/proc/net/icmp"
PROC_TCP6 = "/proc/net/tcp6"
PROC_UDP6 = "/proc/net/udp6"
PROC_PACKET = "/proc/net/packet"
 
# Services
TSERV = dict((TCP_SERVICES[k], k) for k in TCP_SERVICES.keys())
USERV = dict((UDP_SERVICES[k], k) for k in UDP_SERVICES.keys())
 
# IP Protocol Numbers (dec)
IPPROTO_ICMP = 1
IPPROTO_TCP = 6
IPROTOP_IGP = 9
IPPROTO_UDP = 17
 
nostate = set(['04','05','06''07','08','09','0C','0D'])
tcp_payload_hdrs = ['GET|POST|HTTP|HEAD|PUT|PATCH|DELETE|TRACE|OPTIONS|CONNECT']
numeric = False
payloadH = False
payloadHl = False
fillter = ""
 
def get_conn_info(proto,hosts,ports,ipvers):
    ''' returns: pid, exe, uid '''
    uid = 0
 
    line_array = _proc4load(proto,hosts,ports,ipvers)
 
    if line_array == 0:
        return ['?','?','?']
    '''    
    try:
        uid = pwd.getpwuid(int(line_array[7]))[0]       # Get user from UID.
    except:
        uid = line_array[7]
    '''
 
    inode = str(line_array[9])
    if inode == "0":
        return ['.','.','.']
 
    pid = _get_pid_of_inode(inode)          # try get a pid
 
 
    if pid == "NoPid":
        #print(">>>>>>>>>>>NoPID:" + str(hosts) +" "+ str(ports) + "//" + str(line_array))
        return ['-', '-', uid]
 
    try:                                            # try read the process name.
        exe = os.readlink('/proc/'+pid+'/exe').split('/')[-1]
    except:
        exe = None
 
    #print(str(lhost) +" "+ str(lport) +" "+ inode +" "+ pid)
    return [pid, exe, uid]
 
 
def _proc4load(proto,hosts,ports,ipvers):
    ''' Read the table of tcp/udp connections
    tcp/udp: "sl,  local_address, rem_address, st, tx_queue rx_queue, tr tm->when, retrnsmt,   uid , timeout, inode ,..."
    ---- TCP states from https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/include/net/tcp_states.h?id=HEAD
    enum {
    TCP_ESTABLISHED = 1,
    TCP_SYN_SENT,
    TCP_SYN_RECV,
    TCP_FIN_WAIT1,
    TCP_FIN_WAIT2,
    TCP_TIME_WAIT,
    TCP_CLOSE,
    TCP_CLOSE_WAIT,
    TCP_LAST_ACK,
    TCP_LISTEN,
    TCP_CLOSING,    /* Now a valid state */
    TCP_NEW_SYN_RECV,
 
    TCP_MAX_STATES  /* Leave at the end! */
    };
    ----------
    '''
 
    #xhosts = _ip_hexrev(hosts)
    xports = _dec2hex(ports)
 
    if proto == IPPROTO_UDP:
        try:
            procv = PROC_UDP4
            if ipvers == 6:
                procv = PROC_UDP6
            with open(procv,'r') as f:               
                next(f)
                for line in f:
                    line_arrayu = _remove_empty(line.split(' '))
                    l_xhost,l_xport = line_arrayu[1].split(':')
                    if l_xhost not in xMYADDRS:
                        continue
                    if l_xport == xports:
                        return line_arrayu
 
                return 0
        except:
            print("open proc_udp4 error")
            return 0
    elif proto == IPPROTO_TCP:
        try:
            procv = PROC_TCP4
            if ipvers == 6:
                procv = PROC_TCP6
            with open(procv,'r') as f:
                next(f)
                for line in f:
                    line_arrayt = _remove_empty(line.split(' '))
                    if line_arrayt[3] in nostate:        # not some TCP state
                        continue
                    l_xhost,l_xport = line_arrayt[1].split(':')
                    if l_xhost not in xMYADDRS:
                        continue
                    if l_xport == xports:
                        return line_arrayt
 
                return 0
        except:
            print("open proc_tcp error")
            return 0
 
    elif proto == IPPROTO_ICMP:
        try:
            procv = PROC_ICMP4
            if ipvers == 6:
                procv = PROC_ICMP6
            with open(procv,'r') as f:
                next(f)
                for line in f:
                    line_arrayi = _remove_empty(line.split(' '))
                    l_xhost,l_xport = line_arrayi[1].split(':')
                    if l_xhost not in xMYADDRS:
                        continue
                    if l_xport == xports:
                        return line_arrayi
 
                return 0
        except:
            print("open proc_icmp4 error")
            return 0
 
    return 0
 
def _convert_ipv4_port(array):
    host,port = array.split(':')
    return _ip(host),_hex2dec(port)
 
def _hex2dec(s):
    return str(int(s,16))
 
def _dec2hex(p):
    return hex(int(p)).split('x')[-1].upper()
 
def _ip(s):
    ip = [(_hex2dec(s[6:8])),(_hex2dec(s[4:6])),(_hex2dec(s[2:4])),(_hex2dec(s[0:2]))]
    return '.'.join(ip)
 
def _ip6(s):
    ip = [s[6:8],s[4:6],s[2:4],s[0:2],s[14:16],s[12:14],s[10:12],s[8:10],s[22:24],s[20:22],s[18:20],s[16:18],s[30:32],s[28:30],s[26:28],s[24:26]]
    return ':'.join(ip)
 
def _ip_hexrev(ip):
    return ''.join([hex(int(x)+256)[3:] for x in ip.split('.')][::-1]).upper()
 
# IPv6 /proc/net/tcp6 format from expanded ip-address
def _to_v6_proc(s):
	s = s.replace(":", "")
	ip = [s[6:8],s[4:6],s[2:4],s[0:2],s[14:16],s[12:14],s[10:12],s[8:10],s[22:24],s[20:22],s[18:20],s[16:18],s[30:32],s[28:30],s[26:28],s[24:26]]
	return ''.join(ip).upper()
 
def expand_v6(ip):
    ipa = ip.split(':')     # liste
 
    if '' in ipa:
        if ipa.count('') > 1:   # korr ::1 or :::
            for i in range(ipa.count('')-1):
                ipa.remove('')
 
        miss = 8 - len(ipa) +1
        for i in range(miss):
            ipa.insert(ipa.index('')+i, '0000')        
        ipa.remove('')
 
        return ':'.join(["%04x" % x for x in [int(x, 16) for x in ipa]])
    else:
        return ':'.join(["%04x" % x for x in [int(x, 16) for x in ipa]])
 
 
def _remove_empty(array):
    return [x for x in array if x != '']
 
def _get_pid_of_inode(inode):
    s_term = r'^socket\:\['+ inode +r'\]$'
    for item in glob.iglob('/proc/[0-9]*/fd/[0-9]*'):
        try:
            if re.match(s_term,os.readlink(item)):
                return item.split('/')[2]
        except:
            pass
    return "NoPid"
 
def _resolve_ip(host):
    """
    resolve ip und update dictionary res_cache {'ip': 'name'}.
    If resolution for a ip failed, 'name' is n_try ... 0.
    """
    try:
        hname = socket.gethostbyaddr(host)[0]
        res_cache[host] = str(hname)
        return str(hname)
    except:
        res_cache[host] = str(host)
        return str(host)
 
def check_root():
   if os.getuid() == 0:
       return True
   else:
       return False
 
## Define our Custom Action function
def doPackets(packet):
 
    program = "-"
    pid = "-"    
    uid = "-"    
    o_proto = ""
    o_dport = "none"
    o_sport = "none"
    flags = ""
 
    # only local addresses
    if packet[0][1].src in MYADDRS:
        conn_addr = packet[0][1].src
        if packet.haslayer(TCP) or packet.haslayer(UDP) or packet.haslayer(ICMP):
            try:
                conn_port = packet[0][2].sport
            except:
                conn_port = 99999
        o_dir = 1
    else:
        conn_addr = packet[0][1].dst
        if packet.haslayer(TCP) or packet.haslayer(UDP) or packet.haslayer(ICMP):
            try:
                conn_port = packet[0][2].dport
            except:
                conn_port = 99999
        o_dir = 0
 
    if packet.haslayer(TCP) or packet.haslayer(UDP) or packet.haslayer(ICMP):        # grrr, no info in /proc/net/icmp so far. or packet.haslayer(ICMP):
        # logemol casch 
        c_hash = conn_addr+'=:='+str(conn_port)
        if not any(x[0] == c_hash for x in conn_cache):
            # get the connection info from packet
            if packet[0][1].version == 4:
            	spid,sexe,suid = get_conn_info(packet[0][1].proto, conn_addr, conn_port, packet[0][1].version)
            elif packet[0][1].version == 6:
            	spid,sexe,suid = get_conn_info(packet[0][1].nh, conn_addr, conn_port, packet[0][1].version)
            if re.match("^[0-9]+$", spid):
                program = sexe
                pid = spid
                uid = suid
 
                # update cache
                if len(conn_cache) >= cc_maxlen:
                    conn_cache.pop(0)
                conn_cache.append([c_hash,program,pid])
            else:
                program = sexe
                pid = spid
                uid = suid
        else:
            # me honds fom casch
            indx = [x[0] for x in conn_cache].index(c_hash)
            program = conn_cache[indx][1]
            pid = conn_cache[indx][2]
            uid = 0
            # cache aktualisieren
            renew = conn_cache.pop(indx)
            conn_cache.append(renew)
 
    try:
        filter_prog
    except:
        pass
    else:
        if filter_prog.startswith('not-'):
            if program == filter_prog[4:]:
                return
        else:
            if program != filter_prog:
                return
 
 
    o_payload = ""
 
    if packet.haslayer(UDP):
        o_proto = "UDP"
        try:
            o_dport = "\033[1m"+USERV[packet[0][2].dport]+"\033[0m"
        except:
            o_dport = str(packet[0][2].dport)
        try:
            o_sport = "\033[1m"+USERV[packet[0][2].sport]+"\033[0m"
        except:
            o_sport = str(packet[0][2].sport)
        flags = ""
        #o_payload = _to_str(packet[0].sprintf('%10s,UDP.payload%'))
    elif packet.haslayer(TCP):
        o_proto = "TCP"
        try:
            o_dport = "\033[1m"+TSERV[packet[0][2].dport]+"\033[0m"
        except:
            o_dport = str(packet[0][2].dport)
        try:
            o_sport = "\033[1m"+TSERV[packet[0][2].sport]+"\033[0m"
        except:
            o_sport = str(packet[0][2].sport)
        flags = packet[0].sprintf('%3s,TCP.flags%')
        if payloadH == True:
            if packet.haslayer(Raw):
                #tpld = packet[0].sprintf('%TCP.payload%')
                tpld = _to_str(packet[0][TCP].load)
                tpldhead = tpld[0:8]
                #print("tpld:" + tpldhead)
                if re.match(r'GET|POST|HTTP|HEAD|PUT|PATCH|DELETE|TRACE|OPTIONS|CONNECT.*', tpldhead):
                    if payloadHl == True:
                        o_payload = str(tpld)
                    else:
                        request_line, gaga = tpld.split('\r\n', 1)
                        o_payload = str(request_line)
                    #o_payload = tpld[0:20]
    elif packet.haslayer(ICMP):
        o_proto = "ICMP"
        if conn_port == 99999:
            o_dport = "-"
            o_sport = "-"
        else:
            try:
                o_dport = "\033[1m"+USERV[packet[0][2].sport]+"\033[0m"
            except:
                o_dport = str(packet[0][2].sport)
            try:
                o_sport = "\033[1m"+USERV[packet[0][2].dport]+"\033[0m"
            except:
                o_sport = str(packet[0][2].dport)
        flags = "["+packet[0].sprintf('%ICMP.type%') + "/" + packet[0].sprintf('%ICMP.code%')+"]"
    else:
        layerukn = packet[0][1].getlayer(1)
        if layerukn is None:
            o_proto = "UNKNOWN"
        else:
            #print("Layer:", xxl1.name)
            o_proto = layerukn.name
 
        #o_proto = "UNKNOWN"
 
    if packet[0][1].version == 4:
    	packlen = str(packet[0][1].len)
    if packet[0][1].version == 6:
    	packlen = str(packet[0][1].plen)
 
    if o_dir == 1:
        if numeric == False:
            #if res_cache.has_key(packet[0][1].dst):
            if packet[0][1].dst in res_cache:
                rem_name = res_cache[packet[0][1].dst]
            else:
                rem_name = _resolve_ip(packet[0][1].dst)
        else:
            rem_name = packet[0][1].dst
 
        #return "\033[1m "+str(packet[0].time)+" "+str(program)+"\033[0m" +"/"+ str(pid) + " - " + o_proto + ": " + packet[0][1].src + ":" + o_sport + "\033[1m\033[31m  ->>>  \033[0m" + rem_name + ":" + o_dport + " " + flags + " Len:" + str(packet[0][1].len) + " : " + o_payload          
        return "\033[1m"+str(program)+"\033[0m" +"/"+ str(pid) + " - " + o_proto + ": " + packet[0][1].src + ":" + o_sport + "\033[1m\033[31m  ->>>  \033[0m" + rem_name + ":" + o_dport + " " + flags + " Len:" + packlen + " : " + o_payload
    else:
        if numeric == False:
            #if res_cache.has_key(packet[0][1].src):
            if packet[0][1].src in res_cache:
                rem_name = res_cache[packet[0][1].src]
            else:
                rem_name = _resolve_ip(packet[0][1].src)
        else:
            rem_name = packet[0][1].src
 
        return "\033[1m"+str(program)+"\033[0m" +"/"+ str(pid) + " - " + o_proto + ": " + packet[0][1].dst + ":" + o_dport + "\033[1m\033[36m  <<<-  \033[0m" + rem_name + ":" + o_sport + " " + flags + " Len:" + packlen + " : " + o_payload
 
 
 
## -- Ond denn s'Hooptprogramm
 
# root check
if not check_root():
    print("This program needs root privileges !\nThats because of reading the /proc filesystem and using libpcap functions.\nSo I give up\n")
    conf.sniff_promisc=0
    conf.sniff_promisc=0
    sys.exit()
 
# get the interfaces
ifaces = subprocess.getoutput("ls /sys/class/net")
iface_list = ifaces.split('\n')
 
rfilter = "ip or ip6"
print("")
# commandline params
parser = argparse.ArgumentParser(description='sisniff V'+VERSION+"\n2017-2019 by sigi <https://wiki.zweiernet.ch/wiki/sisniff>",
                                   formatter_class=argparse.RawDescriptionHelpFormatter)
parser.add_argument('-i', help="Interface (required)", choices=iface_list, required=True)
parser.add_argument('-n', help="Do not resolve IP-Addresses", action="store_true")
parser.add_argument('-p', help='Filter by program name ([not-] negates)', type=str, metavar='program|not-program')
parser.add_argument('-4', dest='v4', help="Only IPv4", action="store_true")
parser.add_argument('-6', dest='v6', help="Only IPv6", action="store_true")
parser.add_argument('-pH', help="Show HTTP Payload", action="store_true")
parser.add_argument('-pHl', help="Show HTTP Payload, long output", action="store_true")
parser.add_argument('filter', nargs='?', help="Filter (BPF syntax) on top of IP (in dbl-quotes \"...\")", type=str)
args = parser.parse_args()
iface = args.i
if args.n:
    numeric = True
if args.v4:
	rfilter = "ip"
if args.v6:
	rfilter = "ip6"
if args.pH:
    payloadH = True
if args.pHl:
    payloadH = True
    payloadHl = True
if args.filter:
    fillter = " and (" + args.filter + ")"
    print("> Applying Filter: \"" + rfilter + fillter + "\"") 
if args.p:
    filter_prog = args.p
 
 
# local addresses
if args.v6:
	MYADDRS=[]
	xMYADDRS = []
else:
	MYADDRS = _remove_empty(os.popen("ip addr show " + iface + " | egrep 'inet ' | awk '{{print $2}}' | awk -F'/' '{{print $1}}'").read().split())
	MYADDRS.append('0.0.0.0')
	MYADDRS.append('127.0.0.1')
	xMYADDRS = [_ip_hexrev(x) for x in MYADDRS]  
if args.v4:
	MYADDRS6=[]
else:
	MYADDRS6 = _remove_empty(os.popen("ip addr show " + iface + " | egrep 'inet6' | grep -vi fe80 | awk '{{print $2}}' | awk -F'/' '{{print $1}}'").read().split())
	MYADDRS6.append(':::')
	MYADDRS6.append('::1')
	MYADDRS = MYADDRS + MYADDRS6
xMYADDRS = xMYADDRS + [_to_v6_proc(expand_v6(x)) for x in MYADDRS6]
print("> My IP-Addresses: " + str(MYADDRS))
 
# confirmed connections cache (ringboffer)
conn_cache = []
cc_maxlen = 20
 
# resolver cache
res_cache = {}
n_try = 3
print("")
print("Prog/PID mavericks: \033[1m?/?\033[0m = No entry in /proc/net/xxx; \033[1m-/-\033[0m = No PID for Inode found; \033[1m./.\033[0m = Inode=0;")
print("")
print("Program/PID: Local addr:port <<->> Remote addr:port [Flags] Len:length : [Payload]")
print("-------------------------------------------------------------------------------")
 
# sniff, filtering for IP traffic
sniff(filter=rfilter+fillter,iface=iface,prn=doPackets, store=0)
 
## -- oond denn isch schloss

Von «https://wiki.zweiernet.ch/mediawiki/index.php?title=Sisniff&oldid=498»