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ASN(1) User Commands ASN(1)

NAME

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

SYNOPSIS

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

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.

OPTIONS

(enable trace)
Enable AS path trace to the TARGET (this is the default behavior)
(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)
(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
(ASN Suggest)
Lookup AS names and numbers matching TARGET
(Transit/Upstream lookup)
Inspect BGP updates and ASPATHs for the TARGET address/prefix and identify possible transit/upstream autonomous systems
(Country CIDR)
Lookup all IPv4/v6 CIDR blocks allocated to the TARGET country
(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
(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
(organization search)
Force TARGET to be treated as an Organization Name
(monochrome output)
Disable colored output
(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.
(compact JSON output)
Set output to compact JSON mode (ideal for machine parsing)
(pretty-printed JSON output)
Set output to pretty-printed JSON mode
(help)
Show this help screen
(lookup server)
Launch the script in server mode. See SERVER OPTIONS below

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.

SERVER OPTIONS

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).
TCP Port to bind the listening server to (e.g., 'asn -l 12345').
Default value: 49200.
IP address and port to bind the listening server to (e.g., 'asn -l ::1 12345').
(verbose)
Enable verbose output and debug messages in server mode.
Allow only given hosts to connect to the server.
A file of hosts allowed to connect to the server.
Deny given hosts from connecting to the server.
A file of hosts denied from connecting to the server.
The maximum number of simultaneous connections accepted by the server. 100 is the default.

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').

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)

SEE ALSO

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

AUTHOR

Project author: nitefood <nitefood0@gmail.com>

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

July 2024 0.77.0