utils.py 文件源码

def calc_subnet(ipaddr, prefix, is_ipv6=False):
    if is_ipv6 and prefix == 128: return ipaddr
    if not is_ipv6 and prefix == 32: return ipaddr

    q = int(prefix / 8)
    r = prefix % 8

    if is_ipv6:
        byte_ipaddr = socket.inet_pton(socket.AF_INET6, ipaddr)
        results = list(bytes(16))
    else:
        byte_ipaddr = socket.inet_pton(socket.AF_INET, ipaddr)
        results = list(bytes(4))

    results[0:q] = byte_ipaddr[0:q]
    v = 0
    for n in range(r + 1):
        if n == 0: continue
        v += 2 ** (8 - n)

    results[q] = byte_ipaddr[q] & v
    if is_ipv6:
        return socket.inet_ntop(socket.AF_INET6, bytes(results))
    else:
        return socket.inet_ntop(socket.AF_INET, bytes(results))