root / snf-cyclades-app / synnefo / logic / ippool.py @ 8a4a931d
History | View | Annotate | Download (2.5 kB)
| 1 |
import ipaddr |
|---|---|
| 2 |
|
| 3 |
from bitarray import bitarray |
| 4 |
from base64 import b64encode, b64decode |
| 5 |
|
| 6 |
|
| 7 |
class IPPool(object): |
| 8 |
def __init__(self, network): |
| 9 |
self.net = network
|
| 10 |
self.network = ipaddr.IPNetwork(self.net.subnet) |
| 11 |
|
| 12 |
gateway = self.net.gateway
|
| 13 |
self.gateway = gateway and ipaddr.IPAddress(gateway) or None |
| 14 |
|
| 15 |
if self.net.reservations: |
| 16 |
self.reservations = bitarray()
|
| 17 |
self.reservations.fromstring(b64decode(self.net.reservations)) |
| 18 |
else:
|
| 19 |
numhosts = self.network.numhosts
|
| 20 |
self.reservations = bitarray(numhosts)
|
| 21 |
self.reservations.setall(False) |
| 22 |
self.reservations[0] = True |
| 23 |
self.reservations[numhosts - 1] = True |
| 24 |
# if self.net.type == 'PUBLIC_ROUTED':
|
| 25 |
# self.reservations[numhosts - 2] = True
|
| 26 |
|
| 27 |
def _contains(self, address): |
| 28 |
if address is None: |
| 29 |
return False |
| 30 |
addr = ipaddr.IPAddress(address) |
| 31 |
|
| 32 |
return (addr in self.network) |
| 33 |
|
| 34 |
def _address_index(self, address): |
| 35 |
"""Convert IP address to bitarray index
|
| 36 |
|
| 37 |
"""
|
| 38 |
if not self._contains(address): |
| 39 |
raise Exception("%s does not contain %s" % (str(self.network), address)) |
| 40 |
addr = ipaddr.IPAddress(address) |
| 41 |
|
| 42 |
return int(addr) - int(self.network.network) |
| 43 |
|
| 44 |
def _mark(self, address, value): |
| 45 |
index = self._address_index(address)
|
| 46 |
self.reservations[index] = value
|
| 47 |
|
| 48 |
def reserve(self, address): |
| 49 |
self._mark(address, True) |
| 50 |
|
| 51 |
def release(self, address): |
| 52 |
self._mark(address, False) |
| 53 |
|
| 54 |
def is_reserved(self, address): |
| 55 |
index = self._address_index(address)
|
| 56 |
return self.reservations[index] |
| 57 |
|
| 58 |
def is_full(self): |
| 59 |
return self.reservations.all() |
| 60 |
|
| 61 |
def count_reserved(self): |
| 62 |
return self.reservations.count(True) |
| 63 |
|
| 64 |
def count_free(self): |
| 65 |
return self.reservations.count(False) |
| 66 |
|
| 67 |
def get_map(self): |
| 68 |
return self.reservations.to01().replace("1", "X").replace("0", ".") |
| 69 |
|
| 70 |
def get_free_address(self): |
| 71 |
if self.is_full(): |
| 72 |
raise IPPool.IPPoolExhausted("%s if full" % str(self.network)) |
| 73 |
|
| 74 |
index = self.reservations.index(False) |
| 75 |
address = str(self.network[index]) |
| 76 |
self.reserve(address)
|
| 77 |
return address
|
| 78 |
|
| 79 |
def save(self): |
| 80 |
self._update_network()
|
| 81 |
self.net.save()
|
| 82 |
|
| 83 |
def _update_network(self): |
| 84 |
self.net.reservations = b64encode(self.reservations.tostring()) |
| 85 |
|
| 86 |
class IPPoolExhausted(Exception): |
| 87 |
pass
|