ASN(1)

💅 ASN(1) — User Commands, bestie edition

okay so first of all, this is a User Commands manual page, and it's page 1 of the manual, which is the section for user commands. iykyk. it's called asn and it's literally the moment. 🦋

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✨ NAME ✨

asn — ASN / RPKI validity / BGP stats / IPv4v6 / Prefix / ASPath / Organization / IP reputation lookup tool

no cap, that's a whole lot of jobs for one little command and she ate every single one. 👑

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🌸 SYNOPSIS 🌸

asn [OPTIONS] [TARGET]
asn [-v] -l [SERVER OPTIONS]

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💖 DESCRIPTION 💖

ASN is a tool for performing various lookup operations related to ASN (Autonomous System Number), RPKI validity, BGP statistics, IPv4/v6 addresses, prefixes, ASPaths, organizations, and IP reputations.

that's the whole vibe: you give it a thing, it tells you everything about the thing. main character energy fr fr. ✨

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🎀 OPTIONS 🎀

• -t — (enable trace) — Turn on AS path trace to the TARGET. this is literally the default behavior, so it's giving "just confirming the vibe" 💅
• -n — (no trace | no additional INETNUM lookups) — Disable tracing the AS path to the TARGET (for IP targets), or Disable additional (unannounced / announced by other AS) INETNUM lookups for the TARGET (for AS targets). it's the off-switch for the tracing, depending on what kind of target you handed her.
• -d — (detailed) — Output detailed hop info during the AS path trace to the TARGET. This option also enables RPKI validation/BGP hijacking detection for every hop. every hop gets the full report card bestie 🫶
• -a — (ASN Suggest) — Lookup AS names and numbers matching TARGET. it's giving autocomplete but for autonomous systems.
• -u — (Transit/Upstream lookup) — Inspect BGP updates and ASPATHs for the TARGET address/prefix and identify possible transit/upstream autonomous systems. who's upstream? we're finding out. 🔥
• -c — (Country CIDR) — Lookup all IPv4/v6 CIDR blocks allocated to the TARGET country.
• -g — (Bulk Geolocate) — Geolocate all IPv4/v6 addresses passed as TARGET. This mode supports multiple targets, stdin input and IP extraction from input, e.g.

asn -g < /var/log/apache2/error.log or echo 1.1.1.1 2.2.2.2 | asn -g

• -s — (Shodan scan) — Query Shodan's InternetDB for CVE/CPE/Tags/Ports/Hostnames data about TARGET. This mode supports multiple targets and stdin input, e.g.

asn -s < iplist or echo 1.1.1.0/24 google.com | asn -s

• -o — (organization search) — Force TARGET to be treated as an Organization Name.
• -m — (monochrome output) — Disable colored output. no rainbow bestie, we're going plain 😭
• -v — (verbose) — Enable (and log to $HOME/asndebug.log) debug messages (URLs being queried and variable names being assigned). API call response data (i.e. the JSON output) is logged to the logfile. she's telling you EVERYTHING. the whole tea. 🍓
• -j — (compact JSON output) — Set output to compact JSON mode (ideal for machine parsing).
• -J — (pretty-printed JSON output) — Set output to pretty-printed JSON mode. same data, better outfit 💅
• -h — (help) — Show this help screen.
• -l — (lookup server) — Launch the script in server mode. See SERVER OPTIONS below.

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🦋 TARGET 🦋

• <AS Number> — Lookup matching ASN and BGP announcements/neighbours data.
• <IPv4/IPv6> — Lookup matching route(4/6), IP reputation, and ASN data.
• <Prefix> — Lookup matching ASN data.
• <host.name.tld> — Lookup matching IP, route, and ASN data. Supports multiple IPs — e.g. DNS RR.
• <URL> — Extract hostname/IP from the URL and lookup relative data. Supports any protocol prefix, non-standard ports, and prepended credentials.
• <Organization Name> — Search by company name and lookup network ranges exported by (or related to) the company.

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🌈 SERVER OPTIONS 🌈

• BIND_ADDRESS — IP address (v4/v6) to bind the listening server to (e.g., asn -l 0.0.0.0). Default value: 127.0.0.1 (IPv4) or ::1 (IPv6).
• BIND_PORT — TCP Port to bind the listening server to (e.g., asn -l 12345). Default value: 49200.
• BIND_ADDRESS BIND_PORT — IP address and port to bind the listening server to (e.g., asn -l ::1 12345).
• -v — (verbose) — Enable verbose output and debug messages in server mode.
• --allow host[,host,...] — Allow only given hosts to connect to the server.
• --allowfile file — A file of hosts allowed to connect to the server.
• --deny host[,host,...] — Deny given hosts from connecting to the server.
• --denyfile file — A file of hosts denied from connecting to the server.
• -m, --max-conns <n> — The maximum number of simultaneous connections accepted by the server. 100 is the default.

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💜 NOTES 💜

Every option in server mode (after -l) is passed directly to the ncat listener. Refer to man ncat for more details on the available commands.

Unless specified, the default IP:PORT values of 127.0.0.1:49200 (for IPv4) or [::1]:49200 (for IPv6) will be used (e.g., asn -l).

fr fr, she's just handing your flags straight to ncat. know what you're passing down the line bestie. 🧚

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⭐ EXAMPLES ⭐

Example server usage:

asn -l (starts server on default IP(v4/v6):PORT)

asn -l 0.0.0.0 --allow 192.168.0.0/24,192.168.1.0/24,192.168.2.245
(binds to all available IPv4 interfaces on the default port, allowing
only connections from the three specified subnets)

asn -l :: 2222 --allow 2001:DB8::/32 (binds to all available IPv6
interfaces on port 2222, allowing only connections from the specified
prefix)

asn -v -l 0.0.0.0 --allowfile ~/goodips.txt -m 5 (verbose mode, bind to
all IPv4 interfaces, use an allowfile with allowed addresses, accept a
maximum of 5 concurrent connections)

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💀 SEE ALSO 💀

To file a bug report or feature request, please open an issue on the project homepage: https://github.com/nitefood/asn

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👑 AUTHOR 👑

Project author: nitefood <nitefood0@gmail.com>

This manpage was created by Marcos Rodrigues de Carvalho (aka oday) <marcosrcarvalho42@gmail.com>

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and that's the whole page bestie 💖 this is version 0.77.0, dated July 2024, straight from the User Commands section of the manual — go forth and look up every ASN you can find, periodt. 🎀✨