JezK
Edit File: subnets.py
# Add/remove subnets to sites. # # Copyright (C) Catalyst.Net Ltd 2015 # Copyright Matthieu Patou <mat@matws.net> 2011 # # Catalyst.Net's contribution was written by Douglas Bagnall # <douglas.bagnall@catalyst.net.nz>. # # This program is free software; you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation; either version 3 of the License, or # (at your option) any later version. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License # along with this program. If not, see <http://www.gnu.org/licenses/>. # import ldb from ldb import FLAG_MOD_ADD, FLAG_MOD_REPLACE, LdbError from . sites import SiteNotFoundException class SubnetException(Exception): """Base element for Subnet errors""" pass class SubnetNotFound(SubnetException): """The subnet requested does not exist.""" pass class SubnetAlreadyExists(SubnetException): """The subnet being added already exists.""" pass class SubnetInvalid(SubnetException): """The subnet CIDR is invalid.""" pass class SiteNotFound(SubnetException): """The site to be used for the subnet does not exist.""" pass def create_subnet(samdb, configDn, subnet_name, site_name): """Create a subnet and associate it with a site. :param samdb: A samdb connection :param configDn: The DN of the configuration partition :param subnet_name: name of the subnet to create (a CIDR range) :return: None :raise SubnetAlreadyExists: if the subnet to be created already exists. :raise SiteNotFound: if the site does not exist. """ ret = samdb.search(base=configDn, scope=ldb.SCOPE_SUBTREE, expression='(&(objectclass=Site)(cn=%s))' % ldb.binary_encode(site_name)) if len(ret) != 1: raise SiteNotFound('A site with the name %s does not exist' % site_name) dn_site = ret[0].dn if not isinstance(subnet_name, str): raise SubnetInvalid("%s is not a valid subnet (not a string)" % subnet_name) dnsubnet = ldb.Dn(samdb, "CN=Subnets,CN=Sites") if dnsubnet.add_base(configDn) == False: raise SubnetException("dnsubnet.add_base() failed") if dnsubnet.add_child("CN=X") == False: raise SubnetException("dnsubnet.add_child() failed") dnsubnet.set_component(0, "CN", subnet_name) try: m = ldb.Message() m.dn = dnsubnet m["objectclass"] = ldb.MessageElement("subnet", FLAG_MOD_ADD, "objectclass") m["siteObject"] = ldb.MessageElement(str(dn_site), FLAG_MOD_ADD, "siteObject") samdb.add(m) except ldb.LdbError as e: (enum, estr) = e.args if enum == ldb.ERR_INVALID_DN_SYNTAX: raise SubnetInvalid("%s is not a valid subnet: %s" % (subnet_name, estr)) elif enum == ldb.ERR_ENTRY_ALREADY_EXISTS: # Subnet collisions are checked by exact match only, not # overlapping range. This won't stop you creating # 10.1.1.0/24 when there is already 10.1.0.0/16, or # prevent you from having numerous IPv6 subnets that refer # to the same range (e.g 5::0/16, 5::/16, 5:0:0::/16). raise SubnetAlreadyExists('A subnet with the CIDR %s already exists' % subnet_name) else: raise def delete_subnet(samdb, configDn, subnet_name): """Delete a subnet. :param samdb: A samdb connection :param configDn: The DN of the configuration partition :param subnet_name: Name of the subnet to delete :return: None :raise SubnetNotFound: if the subnet to be deleted does not exist. """ dnsubnet = ldb.Dn(samdb, "CN=Subnets,CN=Sites") if dnsubnet.add_base(configDn) == False: raise SubnetException("dnsubnet.add_base() failed") if dnsubnet.add_child("CN=X") == False: raise SubnetException("dnsubnet.add_child() failed") dnsubnet.set_component(0, "CN", subnet_name) try: ret = samdb.search(base=dnsubnet, scope=ldb.SCOPE_BASE, expression="objectClass=subnet") if len(ret) != 1: raise SubnetNotFound('Subnet %s does not exist' % subnet_name) except LdbError as e1: (enum, estr) = e1.args if enum == ldb.ERR_NO_SUCH_OBJECT: raise SubnetNotFound('Subnet %s does not exist' % subnet_name) samdb.delete(dnsubnet) def rename_subnet(samdb, configDn, subnet_name, new_name): """Rename a subnet. :param samdb: A samdb connection :param configDn: The DN of the configuration partition :param subnet_name: Name of the subnet to rename :param new_name: New name for the subnet :return: None :raise SubnetNotFound: if the subnet to be renamed does not exist. :raise SubnetExists: if the subnet to be created already exists. """ dnsubnet = ldb.Dn(samdb, "CN=Subnets,CN=Sites") if dnsubnet.add_base(configDn) == False: raise SubnetException("dnsubnet.add_base() failed") if dnsubnet.add_child("CN=X") == False: raise SubnetException("dnsubnet.add_child() failed") dnsubnet.set_component(0, "CN", subnet_name) newdnsubnet = ldb.Dn(samdb, str(dnsubnet)) newdnsubnet.set_component(0, "CN", new_name) try: samdb.rename(dnsubnet, newdnsubnet) except LdbError as e2: (enum, estr) = e2.args if enum == ldb.ERR_NO_SUCH_OBJECT: raise SubnetNotFound('Subnet %s does not exist' % dnsubnet) elif enum == ldb.ERR_ENTRY_ALREADY_EXISTS: raise SubnetAlreadyExists('A subnet with the CIDR %s already exists' % new_name) elif enum == ldb.ERR_INVALID_DN_SYNTAX: raise SubnetInvalid("%s is not a valid subnet: %s" % (new_name, estr)) else: raise def set_subnet_site(samdb, configDn, subnet_name, site_name): """Assign a subnet to a site. This dissociates the subnet from its previous site. :param samdb: A samdb connection :param configDn: The DN of the configuration partition :param subnet_name: Name of the subnet :param site_name: Name of the site :return: None :raise SubnetNotFound: if the subnet does not exist. :raise SiteNotFound: if the site does not exist. """ dnsubnet = ldb.Dn(samdb, "CN=Subnets,CN=Sites") if dnsubnet.add_base(configDn) == False: raise SubnetException("dnsubnet.add_base() failed") if dnsubnet.add_child("CN=X") == False: raise SubnetException("dnsubnet.add_child() failed") dnsubnet.set_component(0, "CN", subnet_name) try: ret = samdb.search(base=dnsubnet, scope=ldb.SCOPE_BASE, expression="objectClass=subnet") if len(ret) != 1: raise SubnetNotFound('Subnet %s does not exist' % subnet_name) except LdbError as e3: (enum, estr) = e3.args if enum == ldb.ERR_NO_SUCH_OBJECT: raise SubnetNotFound('Subnet %s does not exist' % subnet_name) dnsite = ldb.Dn(samdb, "CN=Sites") if dnsite.add_base(configDn) == False: raise SubnetException("dnsites.add_base() failed") if dnsite.add_child("CN=X") == False: raise SubnetException("dnsites.add_child() failed") dnsite.set_component(0, "CN", site_name) dnservers = ldb.Dn(samdb, "CN=Servers") dnservers.add_base(dnsite) try: ret = samdb.search(base=dnsite, scope=ldb.SCOPE_BASE, expression="objectClass=site") if len(ret) != 1: raise SiteNotFoundException('Site %s does not exist' % site_name) except LdbError as e4: (enum, estr) = e4.args if enum == ldb.ERR_NO_SUCH_OBJECT: raise SiteNotFoundException('Site %s does not exist' % site_name) siteDn = str(ret[0].dn) m = ldb.Message() m.dn = dnsubnet m["siteObject"] = ldb.MessageElement(siteDn, FLAG_MOD_REPLACE, "siteObject") samdb.modify(m)