1ASTRACEROUTE(8) netsniff-ng toolkit ASTRACEROUTE(8)
2
6 astraceroute - autonomous system trace route utility
7
9 astraceroute [options]
10
12 astraceroute is a small utility to retrieve path information in a
13 traceroute like way, but with additional geographical location informa‐
14 tion. It tracks the route of a packet from the local host to the remote
15 host by successively increasing the IP's TTL field, starting from 1, in
16 the hope that each intermediate node will send an ICMP TIME_EXCEEDED
17 notification back to the local host when the TTL value is decremented
18 to 0.
19 astraceroute supports IPv4 and IPv6 queries and will display country
21 and city information, if available, the AS number the hop belongs to,
22 and its ISP name. astraceroute also displays timing information and
23 reverse DNS data.
24 Due to astraceroute's configurability, it is also possible to gather
26 some more useful information about the hop regarding what it does and
27 does not allow to pass through. This is done by using clear text
28 strings for probing DPIs or keywords. This tool might be a good start
29 for further in-depth analysis of such systems.
30
32 -H <host>, --host <host>
33 Hostname or IPv4 or IPv6 address of the remote host where the AS route
34 should be traced to. In the case of an IPv6 address or host, option
35 ''-6'' must be used. IPv4 is the default.
36 -p <port>, --port <port>
38 TCP port for the remote host to use. If not specified, the default port
39 used is 80.
40 -i <device>, -d <device>, --dev <device>
42 Networking device to start the trace route from, e.g. eth0, wlan0.
43 -f <ttl>, --init-ttl <ttl>
45 Initial TTL value to be used. This option might be useful if you are
46 not interested in the first n hops, but only the following ones. The
47 default initial TTL value is 1.
48 -m <ttl>, --max-ttl <ttl>
50 Maximum TTL value to be used. If not otherwise specified, the maximum
51 TTL value is 30. Thus, after this has been reached astraceroute exits.
52 -q <num>, --num-probes <num>
54 Specifies the number of queries to be done on a particular hop. The
55 default is 2 query requests.
56 -x <sec>, --timeout <sec>
58 Tells astraceroute the probe response timeout in seconds, in other
59 words the maximum time astraceroute must wait for an ICMP response from
60 the current hop. The default is 3 seconds.
61 -X <string>, --payload <string>
63 Places an ASCII cleartext string into the packet payload. Cleartext
64 that contains whitespace must be put into quotes (e.g.: "censor me").
65 -l <len>, --totlen <len>
67 Specifies the total length of the packet. Payload that does not have a
68 cleartext string in it is padded with random garbage.
69 -4, --ipv4
71 Use IPv4 only requests. This is the default.
72 -6, --ipv6
74 Use IPv6 only requests. This must be used when passing an IPv6 host as
75 an argument.
76 -n, --numeric
78 Tells astraceroute to not perform reverse DNS lookup for hop replies.
79 The reverse option is ''-N''.
80 -u, --update
82 The built-in geo-database update mechanism will be invoked to get Max‐
83 mind's latest version. To configure search locations for databases, the
84 file /etc/netsniff-ng/geoip.conf contains possible addresses. Thus, to
85 save bandwidth or for mirroring Maxmind's databases (to bypass their
86 traffic limit policy), different hosts or IP addresses can be placed
87 into geoip.conf, separated by a newline.
88 -L, --latitude
90 Also show latitude and longitude of hops.
91 -N, --dns
93 Tells astraceroute to perform reverse DNS lookup for hop replies. The
94 reverse option is ''-n''.
95 -S, --syn
97 Use TCP's SYN flag for the request.
98 -A, --ack
100 Use TCP's ACK flag for the request.
101 -F, --fin
103 Use TCP's FIN flag for the request.
104 -P, --psh
106 Use TCP's PSH flag for the request.
107 -U, --urg
109 Use TCP's URG flag for the request.
110 -R, --rst
112 Use TCP's RST flag for the request.
113 -E, --ecn-syn
115 Use TCP's ECN flag for the request.
116 -t <tos>, --tos <tos>
118 Explicitly specify IP's TOS.
119 -G, --nofrag
121 Set IP's no fragmentation flag.
122 -Z, --show-packet
124 Show and dissect the returned packet.
125 -v, --version
127 Show version information and exit.
128 -h, --help
130 Show user help and exit.
131
133 astraceroute -i eth0 -N -S -H netsniff-ng.org
134 This sends out a TCP SYN probe via the ''eth0'' networking device to
135 the remote IPv4 host netsniff-ng.org. This request is most likely to
136 pass. Also, tell astraceroute to perform reverse DNS lookups for each
137 hop.
138 astraceroute -6 -i eth0 -S -E -N -H www.6bone.net
140 In this example, a TCP SYN/ECN probe for the IPv6 host www.6bone.net is
141 being performed. Also in this case, the ''eth0'' device is being used
142 as well as a reverse DNS lookup for each hop.
143 astraceroute -i eth0 -N -F -H netsniff-ng.org
145 Here, we send out a TCP FIN probe to the remote host netsniff-ng.org.
146 Again, on each hop a reverse DNS lookup is being done and the queries
147 are transmitted from ''eth0''. IPv4 is used.
148 astraceroute -i eth0 -N -FPU -H netsniff-ng.org
150 As in most other examples, we perform a trace route to IPv4 host net‐
151 sniff-ng.org and do a TCP Xmas probe this time.
152 astraceroute -i eth0 -N -H netsniff-ng.org -X censor-me -Z
154 In this example, we have a Null probe to the remote host netsniff-
155 ng.org, port 80 (default) and this time, we append the cleartext string
156 "censor-me" into the packet payload to test if a firewall or DPI will
157 let this string pass. Such a trace could be done once without, and once
158 with, a blacklisted string to gather possible information about censor‐
159 ship.
160
162 If a TCP-based probe fails after a number of retries, astraceroute will
163 automatically fall back to ICMP-based probes to pass through firewalls
164 and routers used in load balancing for example.
165 To gather more information about astraceroute's displayed AS numbers,
167 see e.g.: http://bgp.he.net/AS<number>.
168
170 The geographical locations are estimated with the help of Maxmind's
171 GeoIP database and can differ from the real physical location. To
172 decrease the possible errors, update the database regularly using
173 astraceroute's --update option.
174 At some point in time, we need a similar approach to gather more reli‐
176 able path information such as in the paris-traceroute tool.
177 Due to the generic nature of astraceroute, it currently has a built-in
179 mechanism to stop the trace after a fixed number of hops, since the
180 configurable TCP flags can have anything included. It is possible to
181 decrease this number of course. In the future, if a SYN probe is sent
182 out, there should be a listener so that we can stop the trace if we
183 detect a handshake in progress.
184
186 astraceroute is licensed under the GNU GPL version 2.0.
187
189 astraceroute was originally written for the netsniff-ng toolkit by
190 Daniel Borkmann. It is currently maintained by Tobias Klauser
191 <tklauser@distanz.ch> and Daniel Borkmann <dborkma@tik.ee.ethz.ch>.
192
194 netsniff-ng(8), trafgen(8), mausezahn(8), ifpps(8), bpfc(8), flow‐
195 top(8), curvetun(8)
196
198 Manpage was written by Daniel Borkmann.
199
201 This page is part of the Linux netsniff-ng toolkit project. A descrip‐
202 tion of the project, and information about reporting bugs, can be found
203 at http://netsniff-ng.org/.
204Linux 03 March 2013 ASTRACEROUTE(8)