def __contains__(self, item):
item = IPAddr(item)
if item in self.removed: return False
n = item.toUnsigned()
mask = (1 << self.host_size) - 1
nm = (n & mask) | self.network.toUnsigned()
if nm != n: return False
if (n & mask) == mask:
return False
if (n & mask) < self.first:
return False
if (n & mask) > self.last:
return False
return True
class SimpleAddressPool(AddressPool):
"""
Simple AddressPool for simple subnet based pools.
"""
def __init__(self, network="192.168.0.0/24", first=1, last=None,
count=None):
"""
Simple subnet-based address pool
Allocates count IP addresses out of network/network_size, starting
with the first'th. You may specify the end of the range with either
last (to specify the last'th address to use) or count to specify the
number to use. If both are None, use up to the end of all
legal addresses.
Example for all of 192.168.x.x/16:
SimpleAddressPool("192.168.0.0/16", 1, 65534)
"""
network, network_size = parse_cidr(network)
self.first = first
self.network_size = network_size
self.host_size = 32 - network_size
self.network = IPAddr(network)
if last is None and count is None:
self.last = (1 << self.host_size) - 2
elif last is not None:
self.last = last
elif count is not None:
self.last = self.first + count - 1
else:
raise RuntimeError("Cannot specify both last and count")
self.removed = set()
if self.count <= 0: raise RuntimeError("Bad first/last range")
if first == 0: raise RuntimeError("Can't allocate 0th address")
if self.host_size < 0 or self.host_size > 32:
raise RuntimeError("Bad network")
if IPAddr(self.last | self.network.toUnsigned()) not in self:
raise RuntimeError("Bad first/last range")
def __repr__(self):
return str(self)
def __str__(self):
t = self.network.toUnsigned()
t = (IPAddr(t | self.first), IPAddr(t | self.last))
return "<Addresses from %s to %s>" % t
@property
def subnet_mask(self):
return IPAddr(((1 << self.network_size) - 1) << self.host_size)
@property
def count(self):
return self.last - self.first + 1
def __contains__(self, item):
item = IPAddr(item)
if item in self.removed: return False
n = item.toUnsigned()
mask = (1 << self.host_size) - 1
nm = (n & mask) | self.network.toUnsigned()
if nm != n: return False
if (n & mask) == mask:
return False
if (n & mask) < self.first:
return False
if (n & mask) > self.last:
return False
return True
def append(self, item):
item = IPAddr(item)
if item not in self.removed:
if item in self:
raise RuntimeError("%s is already in this pool" % (item,))
else:
raise RuntimeError("%s does not belong in this pool" % (item,))
self.removed.remove(item)
def remove(self, item):
item = IPAddr(item)
if item not in self:
raise RuntimeError("%s not in this pool" % (item,))
self.removed.add(item)
def __len__(self):
return (self.last - self.first + 1) - len(self.removed)
def __getitem__(self, index):
if index < 0:
raise RuntimeError("Negative indices not allowed")
if index >= len(self):
raise IndexError("Item does not exist")
c = self.first
# Use a heuristic to find the first element faster (we hope)
# Note this means that removing items changes the order of
# our "list".
c += len(self.removed)
while c > self.last:
c -= self.count
while True:
addr = IPAddr(c | self.network.toUnsigned())
if addr not in self.removed:
assert addr in self
index -= 1
if index < 0:
return addr
c += 1
if c > self.last:
c -= self.count
