subnets.py 11.5 KB
Newer Older
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
# Copyright 2013 GRNET S.A. All rights reserved.
#
# Redistribution and use in source and binary forms, with or
# without modification, are permitted provided that the following
# conditions are met:
#
#   1. Redistributions of source code must retain the above
#      copyright notice, this list of conditions and the following
#      disclaimer.
#
#   2. Redistributions in binary form must reproduce the above
#      copyright notice, this list of conditions and the following
#      disclaimer in the documentation and/or other materials
#      provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY GRNET S.A. ``AS IS'' AND ANY EXPRESS
# OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL GRNET S.A OR
# CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
# USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
# AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
# POSSIBILITY OF SUCH DAMAGE.
#
# The views and conclusions contained in the software and
# documentation are those of the authors and should not be
# interpreted as representing official policies, either expressed
# or implied, of GRNET S.A.

from logging import getLogger
from snf_django.lib import api
from snf_django.lib.api import faults

from django.conf.urls import patterns
from django.http import HttpResponse
from django.utils import simplejson as json

from snf_django.lib.api import utils
from synnefo.db.models import Subnet, Network, IPPoolTable
from synnefo.logic import networks

from ipaddr import IPv4Network, IPv6Network, IPv4Address, IPAddress, IPNetwork

log = getLogger(__name__)


def subnet_command(action):
    def decorator(func):
        @wraps(func)
        @transaction.commit_on_success()
        def wrapper(subnet, *args, **kwargs):
            return func(subnet, *args, **kwargs)
        return wrapper
    return decorator


def list_subnets(user_id):
    """List all subnets of a user"""
    log.debug('list_subnets')

    user_subnets = Subnet.objects.filter(network__userid=user_id)
    subnets_dict = [subnet_to_dict(sub)
                    for sub in user_subnets.order_by('id')]

    return subnets_dict


@transaction.commit_on_success
def create_subnet(network_id, cidr, name, ipversion, gateway, dhcp, slac,
                  dns_nameservers, allocation_pools, host_routes, user_id):
    """
    Create a subnet
    network_id and the desired cidr are mandatory, everything else is optional
    """
    try:
        network = Network.objects.get(id=network_id)
    except Network.DoesNotExist:
        raise api.faults.ItemNotFound("No networks found with that id")

    if ipversion not in [4, 6]:
        raise api.faults.BadRequest("Malformed IP version type")

    # Returns the first available IP in the subnet
    if ipversion == 6:
        potential_gateway = str(IPv6Network(cidr).network + 1)
        check_number_of_subnets(network, 6)
    else:
        potential_gateway = str(IPv4Network(cidr).network + 1)
        check_number_of_subnets(network, 4)

    if ipversion == 6:
        networks.validate_network_params(None, None, cidr, gateway)
        if slac is not None:
            dhcp = check_boolean_value(slac, "enable_slac")
        else:
            dhcp = check_boolean_value(dhcp, "dhcp")
    else:
        networks.validate_network_params(cidr, gateway)
        dhcp = check_boolean_value(dhcp, "dhcp")

    name = check_name_length(name)

    gateway_ip = IPAddress(gateway)
    cidr_ip = IPNetwork(cidr)

    sub = Subnet.objects.create(name=name, network=network, cidr=cidr,
                                ipversion=ipversion, gateway=gateway,
                                dhcp=dhcp, host_routes=hosts,
                                dns_nameservers=dns)

    pool_list = list()
    if allocation_pools is not None:
        # If the user specified IP allocation pools, validate them and use them
        if ipversion == 6:
            raise api.faults.Conflict("Can't allocate an IP Pool in IPv6")
        validate_subpools(pool_list, cidr_ip, gateway_ip)
    if allocation_pools is None and ipversion == 4:
        # Check if the gateway is the first IP of the subnet, in this case
        # create a single ip pool
        if int(gateway_ip) - int(cidr_ip) == 1:
            pool_list = [[gateway_ip + 1, cidr_ip.broadcast - 1]]
        else:
            # If the gateway isn't the first available ip, create two different
            # ip pools adjacent to said ip
            pool_list.append([cidr_ip.network + 1, gateway_ip - 1])
            pool_list.append([gateway_ip + 1, cidr_ip.broadcast - 1])

    if pool_list:
        create_ip_pools(pool_list, cidr_ip, sub)

    return sub


def get_subnet(sub_id):
    """Show info of a specific subnet"""
    log.debug('get_subnet %s', sub_id)
    try:
        subnet = Subnet.objects.get(id=sub_id)
    except Subnet.DoesNotExist:
        raise api.faults.ItemNotFound("Subnet not found")

    subnet_dict = subnet_to_dict(subnet)
    return subnet_dict


def delete_subnet():
    """
    Delete a subnet, raises BadRequest
    A subnet is deleted ONLY when the network that it belongs to is deleted
    """
    raise api.faults.BadRequest("Deletion of a subnet is not supported")


@transaction.commit_on_success
def update_subnet(sub_id, name):
    """
    Update the fields of a subnet
    Only the name can be updated
    """
    log.info('Update subnet %s, name %s', % (sub_id, name))

    try:
        subnet = Subnet.objects.get(id=sub_id)
    except:
        raise api.faults.ItemNotFound("Subnet not found")

    check_name_length(name)

    subnet.name = name
    subnet.save()

    return subnet


#Utility functions
def subnet_to_dict(subnet):
    """Returns a dictionary containing the info of a subnet"""
    dns = check_empty_lists(subnet.dns_nameservers)
    hosts = check_empty_lists(subnet.host_routes)
    allocation_pools = subnet.ip_pools.all()
    pools = list()

    if allocation_pools:
        for pool in allocation_pools:
            cidr = IPNetwork(pool.base)
            start = str(cidr.network + pool.offset)
            end = str(cidr.network + pool.offset + pool.size - 1)
            pools.append({"start": start, "end": end})

    dictionary = dict({'id': str(subnet.id),
                       'network_id': str(subnet.network.id),
                       'name': subnet.name if subnet.name is not None else "",
                       'tenant_id': subnet.network.userid,
                       'user_id': subnet.network.userid,
                       'gateway_ip': subnet.gateway,
                       'ip_version': subnet.ipversion,
                       'cidr': subnet.cidr,
                       'enable_dhcp': subnet.dhcp,
                       'dns_nameservers': dns,
                       'host_routes': hosts,
                       'allocation_pools': pools if pools is not None else []})

    if subnet.ipversion == 6:
        dictionary['enable_slac'] = subnet.dhcp

    return dictionary


def string_to_ipaddr(pools):
    """
    Convert [["192.168.42.1", "192.168.42.15"],
            ["192.168.42.30", "192.168.42.60"]]
    to
            [[IPv4Address('192.168.42.1'), IPv4Address('192.168.42.15')],
            [IPv4Address('192.168.42.30'), IPv4Address('192.168.42.60')]]
    and sort the output
    """
    pool_list = [(map(lambda ip_str: IPAddress(ip_str), pool))
                 for pool in pools]
    pool_list.sort()
    return pool_list


def create_ip_pools(pools, cidr, subnet):
    """Create IP Pools in the database"""
    for pool in pools:
        size = int(pool[1]) - int(pool[0]) + 1
        base = str(cidr)
        offset = int(pool[0]) - int(cidr.network)
        ip_pool = IPPoolTable.objects.create(size=size, offset=offset,
                                             base=base, subnet=subnet)


def check_empty_lists(value):
    """Check if value is Null/None, in which case we return an empty list"""
    if value is None:
        return []
    return value


def check_number_of_subnets(network, version):
    """Check if a user can add a subnet in a network"""
    if network.subnets.filter(ipversion=version):
        raise api.faults.BadRequest("Only one subnet of IPv4/IPv6 per "
                                    "network is allowed")


def check_boolean_value(value, key):
    """Check if dhcp value is in acceptable values"""
    if value not in [True, False]:
        raise api.faults.BadRequest("Malformed request, %s must "
                                    "be True or False" % key)
    return value


def check_name_length(name):
    """Check if the length of a name is within acceptable value"""
    if len(str(name)) > Subnet.SUBNET_NAME_LENGTH:
        raise api.faults.BadRequest("Subnet name too long")
    return name


def check_for_hosts_dns(subnet):
    """
    Check if a request contains host_routes or dns_nameservers options
    Expects the request in a dictionary format
    """
    if subnet.get('host_routes', None):
        raise api.faults.BadRequest("Setting host routes isn't supported")
    if subnet.get('dns_nameservers', None):
        raise api.faults.BadRequest("Setting dns nameservers isn't supported")


def get_subnet_fromdb(subnet_id, user_id, for_update=False):
    """
    Return a Subnet instance or raise ItemNotFound.
    This is the same as util.get_network
    """
    try:
        subnet_id = int(subnet_id)
        if for_update:
            return Subnet.objects.select_for_update().get(id=subnet_id,
                                                          network__userid=
                                                          user_id)
        return Subnet.objects.get(id=subnet_id, network__userid=user_id)
    except (ValueError, Subnet.DoesNotExist):
        raise api.faults.ItemNotFound('Subnet not found')


def parse_ip_pools(pools):
    """
    Convert [{'start': '192.168.42.1', 'end': '192.168.42.15'},
             {'start': '192.168.42.30', 'end': '192.168.42.60'}]
    to
            [["192.168.42.1", "192.168.42.15"],
             ["192.168.42.30", "192.168.42.60"]]
    """
    pool_list = list()
    for pool in pools:
        parse = [pool["start"], pool["end"]]
        pool_list.append(parse)
    return pool_list


def validate_subpools(pool_list, cidr, gateway):
    """
    Validate the given IP pools are inside the cidr range
    Validate there are no overlaps in the given pools
    Finally, validate the gateway isn't in the given ip pools
    Input must be a list containing a sublist with start/end ranges as
    ipaddr.IPAddress items eg.,
    [[IPv4Address('192.168.42.11'), IPv4Address('192.168.42.15')],
     [IPv4Address('192.168.42.30'), IPv4Address('192.168.42.60')]]
    """
    if pool_list[0][0] <= cidr.network:
        raise api.faults.Conflict("IP Pool out of bounds")
    elif pool_list[-1][1] >= cidr.broadcast:
        raise api.faults.Conflict("IP Pool out of bounds")

    for start, end in pool_list:
        if start > end:
            raise api.faults.Conflict("Invalid IP pool range")
        # Raise BadRequest if gateway is inside the pool range
        if not (gateway < start or gateway > end):
            raise api.faults.Conflict("Gateway cannot be in pool range")

    # Check if there is a conflict between the IP Poll ranges
    end = cidr.network
    for pool in pool_list:
        if end >= pool[0]:
            raise api.faults.Conflict("IP Pool range conflict")
        end = pool[1]