sinetstat

sinetstat ist eine Alternative zum Linux netstat-Programm.
Es ist nur auf Netzwerksocken ausgelegt, also nur TCP und UDP, keine Unix-Sockets.

Die Highlights:

IPv4inIPv6 Sockets (IPv4-mapped IPv6-Adressen)

Auf Dualstack Linux Systemen (nicht bei OpenBSD oder FreeBSD >5) können 'Zwitter'-Sockets für v6 und v4 Adressen, sogenannte IPv4-mapped IPv6-Adressen (Format: ::FFFF:192.168.1.1), erstellt werden (z.B. Apache). Der hauseigene netstat listet diese Ports aber nur für IPv6 auf, IPv4 Ports bei IPv4-mapped Adressen sind nicht ersichtlich.

sinetstat macht diese sichtbar.

Der Mechanismus dieses sichtbar machen ist allerdings weniger schön: da es meines Wissens keine Abbildung eines solchen Sockets im /proc-Dateisystem gibt, wird halt für jeden v6-Socket ein v4-connect versucht. Wird darauf geantwortet, so versteckt sich ein v4-Socket unter v6. Nicht wirklich schön, aber effektiv.

Command und Argumente

Linux netstat listet in der Program-Spalte das ausführende Programm auf. Das ist dann verwirrend, wenn dieses z.B. über einen Interpreter wie Perl oder Python läuft. Der angezeigte Name ist dann der des Interpreters und nicht des Programms, das durch den Interpreter ausgeführt wird.

Ausgelesen wird dabei der gestrippte Dateiname auf den symbolischen Link /proc[pid]/exe.

sinetstat macht das stadardmässig auch. Mit dem Parameter -w wird aber das eigentliche Programm angezeigt, gefunden in der Datei /proc[pid]/cmdline. Mit dem Parameter -W werden, ebenfalls aus /proc[pid]/cmdline, zusätzlich alle Argumente dieses Programms angezeigt.

UID

sinetstat listet ausserdem noch die UID, unter der das Programm ausgeführt wird.Hilfreich zum greppen.

Eine Uebersicht der Parameter gibt sinetstat -h:

 # sinetstat -h
usage: sinetstat [-h] [-l] [-e] [-r] [-w] [-W] [-t] [-u] [-4] [-6]
netstat utility V1.0
2017 by sigi <https://wiki.zweiernet.ch/wiki/sinetstat>

optional arguments:
  -h, --help  show this help message and exit
  -l          Only listening sockets
  -e          Only established sockets
  -r          Resolve IP-Addresses
  -w          Wide (show cmd)
  -W          Wider (show cmd with arguments)
  -t          Only TCP
  -u          Only UDP
  -4          Only IPv4
  -6          Only IPv6

Download

Die aktuellste Version steht auf GitLab zum Download .

Updates:

V0.93:

neuer Parameter '-e' für 'Established' Verbindungen. Als established gelten alle Verbindungen die nicht in den Zuständen LISTEN|SYN_SENT|SYN_RECV sind.

V0.95:

Anzeige von UDP 'ESTABLISHED'. Ja, scheinbar gibts das, obwohl UDP verbindungslos ist.

Und zwar dann, wenn eine Apllikation einen connect(2) Systemcall auf einem SOCK_DGRAM Socket zu einem Partner macht. Dabei werden dann nur Verbindungen von diesem Partner akzeptiert.

V1.0:

Namensänderung si_netstat -> sinetstat

Neue Parameter '-w' und '-W'.

-w zeigt das Kommando wie es in /proc/<pid>/cmdline zu finden ist.

-W listet zusätzlich die Kommandozeilen-Optionen auf.

V1.1:

Läuft eingeschränkt auch unter nicht-root User.

Und hier für die Ungeduldigen der Python 2.x Code:

#!/usr/bin/python2
 
# (c) 2016 by Siegrist(SystemLoesungen) <PSS @ ZweierNet.ch> 
# Website: [https://wiki.zweiernet.ch/wiki/Sinetstat]
# 
# This program is free software. 
#
# The program is based on a python netstat script that was written by da667 available on https://github.com/da667/netstat
# who had it adapted from Ricardo Pascal, available on http://voorloopnul.com/blog/a-python-netstat-in-less-than-100-lines-of-code.
#
# This version has some improvements make it an acceptable alternative to the original netstat command.
# So it can explore IPv4 in IPv6 listening sockets and some other information over and above the original netstat.
#
# Simply try: 'sinetstat -h'
#
 
 
import pwd
import os
import re
import glob
import socket
import sys
import string
import fcntl
import struct
import argparse
 
 
 
VERSION = '1.01'
 
PROC_TCP4 = "/proc/net/tcp"
PROC_UDP4 = "/proc/net/udp"
PROC_TCP6 = "/proc/net/tcp6"
PROC_UDP6 = "/proc/net/udp6"
 
MAX_IPV4_ADDRESS = 0xffffffff
MAX_IPV6_ADDRESS = 0xffffffffffffffffffffffffffffffff
TCP_STATE = {
        '01':'ESTABLISHED',
        '02':'SYN_SENT',
        '03':'SYN_RECV',
        '04':'FIN_WAIT1',
        '05':'FIN_WAIT2',
        '06':'TIME_WAIT',
        '07':'CLOSE',
        '08':'CLOSE_WAIT',
        '09':'LAST_ACK',
        '0A':'LISTEN',
        '0B':'CLOSING'
        }
 
v4ports = []
opt_l = True
 
 
 
def grep_b(list, search):
    return [True for i in list if search in i]
 
def get_ip_address(ifname):
    s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
    return socket.inet_ntoa(fcntl.ioctl(
        s.fileno(),
        0x8915,  # SIOCGIFADDR
        struct.pack('256s', ifname[:15])
    )[20:24])
 
def _tcp4load():
    ''' Read the table of tcp connections & remove the header  '''
    with open(PROC_TCP4,'r') as f:
        content = f.readlines()
        content.pop(0)
    return content
 
def _tcp6load():
    ''' Read the table of tcpv6 connections & remove the header'''
    with open(PROC_TCP6,'r') as f:
        content = f.readlines()
        content.pop(0)
    return content
 
def _udp4load():
    '''Read the table of udp connections & remove the header '''
    with open(PROC_UDP4,'r') as f:
        content = f.readlines()
        content.pop(0)
    return content
 
def _udp6load():
    '''Read the table of udp connections & remove the header '''
    with open(PROC_UDP6,'r') as f:
        content = f.readlines()
        content.pop(0)
    return content
 
def _hex2dec(s):
    return str(int(s,16))
 
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[12:14],s[14:16],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]]
    #print '66666:', ':'.join(ip), s
    return ':'.join(ip)
 
def _ip6q(s):
    ip = [s[6:8]+s[4:6],s[2:4]+s[0:2],s[12:14]+s[14:16],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]]
    #print '666qqq:', ':'.join(ip), s
    return ':'.join(ip)
 
def _conv_v6(s):
    return s
 
 
 
def _remove_empty(array):
    return [x for x in array if x !='']
 
def _convert_ipv4_port(array):
    host,port = array.split(':')
    return _ip(host),_hex2dec(port)
 
def _convert_ipv6_port(array):
    host,port = array.split(':')
    return _ip6(host),_hex2dec(port)
 
def _convert_ipv6(array):
    host,port = array.split(':')
    return _ip6q(host)
 
def _addr_normal(s):
    return ':'.join(["%x" % x for x in [int(x, 16) for x in s.split(':')]])
 
def _countFollowingZeros(l):
    """Return number of elements containing 0 at the beginning of the list."""
    #print 'aaa:', l
    if len(l) == 0:
        return 0
    elif l[0] != 0:
        return 0
    else:
        return 1 + _countFollowingZeros(l[1:])
 
def _compress_v6(addr):
    hextets = [int(x, 16) for x in addr.split(':')]
    #print hextets
    followingzeros = [0] * 8
    for i in xrange(len(hextets)):
        followingzeros[i] = _countFollowingZeros(hextets[i:])
    # compressionpos is the position where we can start removing zeros
    compressionpos = followingzeros.index(max(followingzeros))
    if max(followingzeros) > 1:
        # genererate string with the longest number of zeros cut out
        # now we need hextets as strings
        hextets = [x for x in _addr_normal(addr).split(':')]
        while compressionpos < len(hextets) and hextets[compressionpos] == '0':
            del(hextets[compressionpos])
        hextets.insert(compressionpos, '')
        if compressionpos + 1 >= len(hextets):
            hextets.append('')
        if compressionpos == 0:
            hextets = [''] + hextets
        return ':'.join(hextets)
    else:
        return _addr_normal(addr)
 
 
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]
        return str(hname)
    except:
        return str(host)
 
 
 
 
def netstat_tcp4():
    '''
    Function to return a list with status of tcp4 connections on Linux systems.
    '''
 
    tcpcontent =_tcp4load()
    tcpresult = []
    for line in tcpcontent:
        line_array = _remove_empty(line.split(' '))     # Split lines and remove empty spaces.
        l_host,l_port = _convert_ipv4_port(line_array[1]) # Convert ipaddress and port from hex to decimal.
        r_host,r_port = _convert_ipv4_port(line_array[2])
        tcp_id = line_array[0]
        state = TCP_STATE[line_array[3]]
        if state != 'LISTEN' and o_listen == True:
            continue
        if ( state == 'LISTEN' or state == 'SYN_SENT' or state == 'SYN_RECV' ) and o_estab == True:
            continue
 
        try:
            uid = pwd.getpwuid(int(line_array[7]))[0]       # Get user from UID.
        except:
            uid = line_array[7]
        inode = line_array[9]                           # Need the inode to get process pid.
        if int(inode) > 0:
            pid = _get_pid_of_inode(inode)
            try:                                            # try read the process name.
                if o_wide == True:
                    with open('/proc/'+pid+'/cmdline','r') as f:
                        exe = ' '.join(f.read().split('\x00')).split(' ')[0]
                elif o_wider == True:
                    with open('/proc/'+pid+'/cmdline','r') as f:
                        exe = ' '.join(f.read().split('\x00'))
                else:
                    exe = os.readlink('/proc/'+pid+'/exe').split('/')[-1]
            except:
                exe = '-'
        else:
            pid = '-'
            exe = '-'
 
        if o_numeric == False:
            r_host = _resolve_ip(r_host)
 
        nline = '%-7s %-24s  %-24s  %-11s  %-8s  %-6s  %-s' % ('TCP4', l_host+': '+l_port, r_host+': '+r_port, state, uid, pid, exe)
 
        tcpresult.append(nline)
 
        # update v4inv6check list
        v4ports.append(l_port)
 
    return tcpresult
 
def netstat_tcp6():
    '''
    This function returns a list of tcp connections utilizing ipv6. 
    '''
    tcpcontent = _tcp6load()
    tcpresult = []
    for line in tcpcontent:
        line_array = _remove_empty(line.split(' '))
        l_host,l_port = _convert_ipv6_port(line_array[1])
        r_host,r_port = _convert_ipv6_port(line_array[2])
        tcp_id = line_array[0]
        state = TCP_STATE[line_array[3]]
        if state != 'LISTEN' and o_listen == True:
            continue
        if ( state == 'LISTEN' or state == 'SYN_SENT' or state == 'SYN_RECV' ) and o_estab == True:
            continue
 
        try:
            uid = pwd.getpwuid(int(line_array[7]))[0]       # Get user from UID.
        except:
            uid = line_array[7]
        inode = line_array[9]
        if int(inode) > 0:
            pid = _get_pid_of_inode(inode)
            try:                                            # try read the process name.
                if o_wide == True:
                    with open('/proc/'+pid+'/cmdline','r') as f:
                        exe = ' '.join(f.read().split('\x00')).split(' ')[0]
                elif o_wider == True:
                    with open('/proc/'+pid+'/cmdline','r') as f:
                        exe = ' '.join(f.read().split('\x00'))
                else:
                    exe = os.readlink('/proc/'+pid+'/exe').split('/')[-1]
            except:
                exe = '-'
        else:
            pid = '-'
            exe = '-'
 
        nline = '%-7s %-24s  %-24s  %-11s  %-8s  %-6s  %-s' % ('TCP6', _compress_v6(_convert_ipv6(line_array[1]))+': '+l_port, _compress_v6(_convert_ipv6(line_array[2]))+': '+r_port, state, uid, pid, exe)
 
        tcpresult.append(nline)
 
    return tcpresult
 
 
def netstat_tcp4in6():
    '''
    Returns a list of tcp ipv4 in ipv6 listen sockets.
    '''    
    #print xx()
 
    tcpcontent = _tcp6load()
    tcpresult = []
    for line in tcpcontent:
        line_array = _remove_empty(line.split(' '))
        #if TCP_STATE[line_array[3]] != 'LISTEN':
        #	continue
 
        l_host,l_port = _convert_ipv6_port(line_array[1])
        r_host,r_port = _convert_ipv6_port(line_array[2])
        if grep_b(v4ports,l_port):
            continue
        tcp_id = line_array[0]
        state = TCP_STATE[line_array[3]]
        if state != 'LISTEN' and o_listen == True:
            continue
        if ( state == 'LISTEN' or state == 'SYN_SENT' or state == 'SYN_RECV' ) and o_estab == True:
            continue
 
        try:
            uid = pwd.getpwuid(int(line_array[7]))[0]       # Get user from UID.
        except:
            uid = line_array[7]
        inode = line_array[9]
        if int(inode) > 0:
            pid = _get_pid_of_inode(inode)
            try:                                            # try read the process name.
                if o_wide == True:
                    with open('/proc/'+pid+'/cmdline','r') as f:
                        exe = ' '.join(f.read().split('\x00')).split(' ')[0]
                elif o_wider == True:
                    with open('/proc/'+pid+'/cmdline','r') as f:
                        exe = ' '.join(f.read().split('\x00'))
                else:
                    exe = os.readlink('/proc/'+pid+'/exe').split('/')[-1]
            except:
                exe = '-'
        else:
            pid = '-'
            exe = '-'
 
        if l_host == '00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:01':
        	if _check_v4inv6_port("127.0.0.1",l_port):
        	    nline = '%-7s %-24s  %-24s  %-11s  %-8s  %-6s  %-s' % ('TCP4in6', '127.0.0.1: '+l_port, _compress_v6(_convert_ipv6(line_array[2]))+': '+r_port, state, uid, pid, exe)
        	    tcpresult.append(nline)
        if l_host == "00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00":
        	if _check_v4inv6_port("0.0.0.0",l_port):
        	    nline = '%-7s %-24s  %-24s  %-11s  %-8s  %-6s  %-s' % ('TCP4in6', '0.0.0.0: '+l_port, _compress_v6(_convert_ipv6(line_array[2]))+': '+r_port, state, uid, pid, exe)
        	    tcpresult.append(nline)
        #else:
        #    for a in MYIFS.split():
        #       _check_v4inv6_port(get_ip_address(a),l_port) 
 
    return tcpresult
 
 
def netstat_udp4():
    '''
    Function to return a list with status of udp connections.
    '''
 
    udpcontent =_udp4load()
    udpresult = []
    for line in udpcontent:
        line_array = _remove_empty(line.split(' '))
        l_host,l_port = _convert_ipv4_port(line_array[1])
        r_host,r_port = _convert_ipv4_port(line_array[2])
        udp_id = line_array[0]
        udp_state = TCP_STATE[line_array[3]]
        if ( udp_state != 'ESTABLISHED' and o_estab == True ) or o_estab == False:
            continue
        if udp_state != 'ESTABLISHED':
            udp_state =' ' #UDP is stateless
        try:
            uid = pwd.getpwuid(int(line_array[7]))[0]       # Get user from UID.
        except:
            uid = line_array[7]
        inode = line_array[9]
        if int(inode) > 0:
            pid = _get_pid_of_inode(inode)
            try:                                            # try read the process name.
                if o_wide == True:
                    with open('/proc/'+pid+'/cmdline','r') as f:
                        exe = ' '.join(f.read().split('\x00')).split(' ')[0]
                elif o_wider == True:
                    with open('/proc/'+pid+'/cmdline','r') as f:
                        exe = ' '.join(f.read().split('\x00'))
                else:
                    exe = os.readlink('/proc/'+pid+'/exe').split('/')[-1]
            except:
                exe = '-'
        else:
            pid = '-'
            exe = '-'
 
        nline = '%-7s %-24s  %-24s  %-11s  %-8s  %-6s  %-s' % ('UDP4', l_host+': '+l_port, r_host+': '+r_port, udp_state, uid, pid, exe)
 
        udpresult.append(nline)
    return udpresult
 
def netstat_udp6():
    '''
    Function to return a list of udp connection utilizing ipv6
    '''
 
    udpcontent =_udp6load()
    udpresult = []
    for line in udpcontent:
        line_array = _remove_empty(line.split(' '))
        l_host,l_port = _convert_ipv6_port(line_array[1])
        r_host,r_port = _convert_ipv6_port(line_array[2])
        udp_id = line_array[0]
        udp_state = TCP_STATE[line_array[3]]
        if ( udp_state != 'ESTABLISHED' and o_estab == True ) or o_estab == False:
            continue
        if udp_state != 'ESTABLISHED':
            udp_state =' ' #UDP is stateless
        try:
            uid = pwd.getpwuid(int(line_array[7]))[0]       # Get user from UID.
        except:
            uid = line_array[7]
        inode = line_array[9]
        if int(inode) > 0:
            pid = _get_pid_of_inode(inode)
            try:                                            # try read the process name.
                if o_wide == True:
                    with open('/proc/'+pid+'/cmdline','r') as f:
                        exe = ' '.join(f.read().split('\x00')).split(' ')[0]
                elif o_wider == True:
                    with open('/proc/'+pid+'/cmdline','r') as f:
                        exe = ' '.join(f.read().split('\x00'))
                else:
                    exe = os.readlink('/proc/'+pid+'/exe').split('/')[-1]
            except:
                exe = '-'
        else:
            pid = '-'
            exe = '-'
 
        nline = '%-7s %-24s  %-24s  %-11s  %-8s  %-6s  %-s' % ('UDP6', _compress_v6(_convert_ipv6(line_array[1]))+': '+l_port, _compress_v6(_convert_ipv6(line_array[2]))+': '+r_port, udp_state, uid, pid, exe)
 
        udpresult.append(nline)
    return udpresult
 
 
def _get_pid_of_inode(inode):
    '''
    To retrieve the process pid, check every running process and look for one using
    the given inode.
    '''
    for item in glob.glob('/proc/[0-9]*/fd/[0-9]*'):
        try:
            if re.search(inode,os.readlink(item)):
                return item.split('/')[2]
        except:
            pass
    return None
 
def check_root():
    if os.getuid() == 0:
        return True
    else:
        return False
 
def _check_v4inv6_port(addr,portnr):
    '''
    check if a v4 port is listening over ip6. Strange, we do a SYN connect for every port not listening v4.
    thats because I think there is no image in the /proc filesystem
    '''
    #print 'aaacc:', addr, portnr
    is_onnected = False
    try:
        try:
            t_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        except:
            print("Error: Can't open socket!\n")
            return False
        t_socket.connect((addr, int(portnr)))
        is_onnected = True
    except:
        is_onnected = False    
    finally:
        if(is_onnected and portnr != t_socket.getsockname()[1]):
            #print("{}:{} Open \n".format(addr, portnr))
            t_socket.close()
            return True
        t_socket.close()
        return False
 
 
if __name__ == '__main__':
    if not check_root():
        print("This program needs root privileges !\nThats because of reading the /proc filesystem and using functions like getpwuid().\nSo I give up\n")
        sys.exit()
 
 
    #print
    # commandline params
    o_numeric = True
    o_listen = False
    o_estab = None
    o_wide = False
    o_wider = False
    o_udp = True
    o_tcp = True
    o_v6 = True
    o_v4 = True
    parser = argparse.ArgumentParser(description='netstat utility V'+VERSION+"\n2017 by sigi <https://wiki.zweiernet.ch/wiki/sinetstat>",
                                   formatter_class=argparse.RawDescriptionHelpFormatter )
    parser.add_argument('-l', help="Only listening sockets", action="store_true")
    parser.add_argument('-e', help="Only established sockets", action="store_true")
    parser.add_argument('-r', help="Resolve IP-Addresses", action="store_true")
    parser.add_argument('-w', help="Wide (show cmd)", action="store_true")
    parser.add_argument('-W', help="Wider (show cmd with arguments)", action="store_true")
    parser.add_argument('-t', help="Only TCP", action="store_true")
    parser.add_argument('-u', help="Only UDP", action="store_true")
    parser.add_argument('-4', dest='v4', help="Only IPv4", action="store_true")
    parser.add_argument('-6', dest='v6', help="Only IPv6", action="store_true")
    args = parser.parse_args()
    if args.r:
        o_numeric = False
    if args.l:
        o_listen = True
    if args.e:
        o_estab = True
        o_listen = False
    if args.w:
        o_wide = True
    if args.W:
        o_wider = True
        o_wide = False
    if args.t:
        o_udp = False 
    if args.u:
        o_tcp = False
    if args.v4:
        o_v6 = False
    if args.v6:
        o_v4 = False
 
 
    # Output
    print '%-7s %-24s  %-24s  %-11s  %-8s  %-6s  %-s' % ('Proto', 'Local Address', 'Remote Address', 'State', 'UID', 'PID', 'Program')
    print '%-7s %-24s  %-24s  %-11s  %-8s  %-6s  %-s' % ('-----', '-------------', '--------------', '-----', '---', '---', '-------')
    #print "\nTCP (v4) Results:\n"
    if o_v4 == True and o_tcp == True: 
        for conn_tcp in netstat_tcp4():
            print conn_tcp
    #print "\nTCP (v4inv6) Results:\n"
    if o_v4 == True and o_tcp == True:
        for conn_tcp46 in netstat_tcp4in6():
            print conn_tcp46
    #print "\nTCP (v6) Results:\n"
    if o_v6 == True and o_tcp == True:
        for conn_tcp6 in netstat_tcp6():
            print conn_tcp6
    #print "\nUDP (v4) Results:\n"
    if o_v4 == True and o_udp == True and not args.l:
        for conn_udp in netstat_udp4():
            print conn_udp
    #print "\nUDP (v6) Results:\n"
    if o_v6 == True and o_udp == True and not args.l:
        for conn_udp6 in netstat_udp6():
            print conn_udp6