PATH6(1)

📦
version 2.2 · 2 versions
, in epel 10, epel 9, fedora 43, fedora 44

💖 NAME 💖

okay so bestie, welcome to the path6(1) page — straight out of the General Commands Manual, no cap ✨ this entire doc is about path6, aka a versatile IPv6-based traceroute tool 🦋

✨ SYNOPSIS ✨

path6 [-d] [-i INTERFACE] [-s SRC_ADDR[/LEN]] [-S LINK_SRC_ADDR] [-D
LINK_DST_ADDR] [-y FRAG_SIZE] [-u DST_OPT_HDR_SIZE] [-U
DST_OPT_U_HDR_SIZE] [-H HBH_OPT_HDR_SIZE] [-r LIMIT] [-p PROBE_TYPE] [-P
PAYLOAD_SIZE] [-a DST_PORT] [-X TCP_FLAGS] [-v] [-h]

🌸 DESCRIPTION 🌸

path6 is an IPv6 traceroute tool, and the way she handles IPv6 Extension Headers?? full support, literally all of them, obsessed 💅

She's part of the SI6 Networks' IPv6 Toolkit: a security assessment suite for the IPv6 protocols 👑

💅 OPTIONS 💅

path6 takes its parameters as command-line options. Each of the options can be specified with a short name (one character preceded with the hyphen character, as e.g. -i) or with a long name (a string preceded with two hyphen characters, as e.g. --interface) 🎀

Most of probe packet details can be specified by means of the available options. When TCP or UDP probe packets are employed, the Source Port of the probe packets is used to encode the probe packet number. iykyk 🧚

ngl bestie, the current version of the tool will only print IPv6 addresses and will not try to reverse-map such IPv6 addresses into hostnames. so don't come for her about names, she's not doing that 😭
  • -i interface, --interface interface — specifies the network interface to be used by the path6 tool. It can be used for overriding the output interface selected based on the local routing table.
  • -s SRC_ADDR, --src-address SRC_ADDR — specifies the IPv6 source address (or IPv6 prefix) to be used for the Source Address of the attack packets. If a prefix is specified, the Source Address is randomly selected from that prefix. random queen behavior ✨
  • -d DST_ADDR, --dst-address DST_ADDR — specifies the IPv6 Destination Address of the target 🎯
  • -S SRC_LINK_ADDR, --src-link-address SRC_LINK_ADDR — can be used to override the link-layer Source Address of the packets.
  • -D DST_LINK_ADDR, --dst-link-address DST_LINK_ADDR — can be used to override the link-layer Destination Address of the outgoing packets.
  • -y SIZE, --frag-hdr SIZE — specifies that the probe packets must be fragmented. The fragment size must be specified as an argument to this option ✂️
  • -u HDR_SIZE, --dst-opt-hdr HDR_SIZE — specifies that a Destination Options header is to be included in the outgoing packet(s). The extension header size must be specified as an argument to this option (the header is filled with padding options). Multiple Destination Options headers may be specified by means of multiple -u options. stack 'em, bestie 🌈
  • -U HDR_SIZE, --dst-opt-u-hdr HDR_SIZE — specifies a Destination Options header to be included in the "unfragmentable part" of the outgoing packet(s). The header size must be specified as an argument to this option (the header is filled with padding options). Multiple Destination Options headers may be specified by means of multiple -U options.
  • -H HDR_SIZE, --hbh-opt-hdr HDR_SIZE — specifies that a Hop-by-Hop Options header is to be included in the outgoing packet(s). The header size must be specified as an argument to this option (the header is filled with padding options). Multiple Hop-by-Hop Options headers may be specified by means of multiple -H options.
  • -f FLOW_LABEL, --flow-LABEL FLOW_LABEL — specifies the Flow Label value of the probe packets. If the special keyword 'random' is specified instead of a number, the Flow Label value of each probe packet will be set to a random value 🎲
  • -m MODE, --output-mode MODE — controls how information is displayed. 'script' specifies that information is output in the following format:
Hop#Address#SflowLabel#RFlowLabel#RTT

where:

  • Hop: Hops from source
  • Address: IPv6 Source Address of the system responding to the probe packet.
  • SflowLabel: Flow Label value originally set in the probe packet.
  • RflowLabel: Flow Label value seen by the system responding to the probe packet.
  • RTT: Round-Trip Time, in milliseconds.

Each line of output corresponds to one probe packet. By default, three (3) probe packets are sent for each hop value 👑

path6 learns the Flow Label values from the IPv6 packets embedded in the payload of ICMPv6 error messages. Thus, in order for the tool to learn the received Flow Label values all the way till the destination host, probe types other than TCP should be employed (see option '-p'). When employing TCP as the probe packet type, the final probe packet will elicit a TCP segment from the target system, rather than an ICMPv6 error message, and thus it will be impossible to learn the Flow Label value received at the target system. When TCP is employed as the probe type, the 'RflowLabel' of the response from the target system will contain the special value 0xffffffff. The value 0xffffffff is not a possible Flow Label value, since the Flow Label field is 20-bits long. so if you see that, that's why, don't panic 🙈

  • -p PROBE_TYPE, --probe-type PROBE_TYPE — specifies the protocol to be used for the probe packets. Possible arguments are: "icmp" (for ICMPv6 Echo Request), "tcp" (for TCP), and "udp" (for UDP). If left unspecified, the probe packets default to ICMPv6 Echo Request 💖
  • -P PAYLOAD_SIZE, --payload-size PAYLOAD_SIZE — specifies the payload size of the probe packets.
  • -o SRC_PORT, --src-port SRC_PORT — specifies the TCP/UDP Source Port. If left unspecified, the Source Port is randomized from the range 1024-65535 🎀
  • -a DST_PORT, --dst-port DST_PORT — specifies the TCP/UDP Destination Port. If left unspecified, the Destination Port defaults to 80 for the TCP case, and a randomized value (in the range 60000-65000) for the UDP case.
  • -X TCP_FLAGS, --tcp-flags TCP_FLAGS — used to set specific the TCP flags. The flags are specified as "F" (FIN), "S" (SYN), "R" (RST), "P" (PSH), "A" (ACK), "U" (URG), "X" (no flags).

If this option is left unspecified, the ACK bit is set on all probe packets.

  • -v, --verbose — selects the "verbosity" of the tool. If this option is left unspecified, only minimum information is printed 🤫
  • -h, --help — print help information for the path6 tool 🫶

🔥 EXAMPLES 🔥

The following sections illustrate typical use cases of the path6 tool.

⭐ Example #1

# path6 -d 2001:db8::1 -u 8 -p icmp

Perform traceroute to 2001:db8::1 employing ICMPv6 echo request packets with a Destination Options extension header of 8 bytes ✨

⭐ Example #2

# path6 -d www.example.com -p icmp -P 500 -y 256

Perform traceroute to the first IPv6 address mapped to by the domain name 'www.example.com', using ICMPv6 Echo Requests with a payload of 500 bytes, fragmenting the probe packets to at most 256 bytes (thus resulting in two IPv6 fragments) ✂️ two little fragments, so cute

⭐ Example #3

# path6 -d 2001:db8::1 -p tcp -a 80

Perform traceroute to the IPv6 address 2001:db8::1, employing TCP segments destined to TCP port 80 as the probe packets 💅

⭐ Example #4

# path6 -d www.si6networks.com -m script -p udp -r 1pps --flow-label random

Perform traceroute to the first IPv6 address corresponding to the domain name 'www.si6networks.com'. Produce 'script' output. Use udp for the probe packets. Send at most 1 probe packets per second. Set the Flow Label of each probe packet to a different random value 🎲🌈

🦋 SEE ALSO 🦋

👑 AUTHOR 👑

The path6 tool and the corresponding manual pages were produced by Fernando Gont <fgont@si6networks.com> for SI6 Networks <https://www.si6networks.com>. iconic, truly 💖

Copyright (c) 2014-2021 Fernando Gont.

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is available at <http://www.gnu.org/licenses/fdl.html>.

and that's the whole page bestie!! 🫶 this one came from the General Commands Manual, and it's filed under PATH6(1) — no date on the footer, she's just timeless like that 💅✨

📦 where this page comes from