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
|