How to get all ip ranges from asn?

Question

I want to get all IP address ranges/blocks from as number. I can search throw google but need to write them manually. I want to get them all at once? Is this possible to get only ip address ranges from websites at once?

Answer 1

If you don't have whois installed, you can achieve similar using a direct TCP connection to the WHOIS server.

For IPv4:

echo '-i origin AS15169' | nc whois.radb.net 43  | grep '^route:'

For IPv6:

echo '-i origin AS15169' | nc whois.radb.net 43  | grep '^route6:'

Similar can be achieved with Python using the socket lib (in the standard library):

import socket

with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
    s.connect(('whois.radb.net', 43))
    s.sendall(b"-i origin AS15169\n")
    result = ''
    while True:
        data = s.recv(16).decode('utf8')
        if not data:
            break
        result += data

result = [i for i in result.split('\n') if i.startswith('route')]
print (result)

Answer 2

You can use whois servers instead of bgp.he.net or any other websites like this.

whois -h whois.radb.net -- '-i origin AS01' | grep 'route:'

Just run this command on your Linux machine.

Answer 3

sh ip bgp regex _<number>$

this shows the advertised netbocks from AS known to the local machine (on a cisco, quagga or FRR router). Some looking glasses will let you make this search (some won't).