Rename validator/ to config/

config/address.py

@@ -0,0 +1,122 @@
+#
+# Copyright (c) 2022 Pim van Pelt
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at:
+#     http://www.apache.org/licenses/LICENSE-2.0
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+import logging
+import config.interface as interface
+import ipaddress
+
+def get_all_addresses_except_ifname(yaml, except_ifname):
+    """ Return a list of all ipaddress.ip_interface() instances in the entire config,
+        except for those that belong to 'ifname'.
+    """
+    ret = []
+    if 'interfaces' in yaml:
+        for ifname, iface in yaml['interfaces'].items():
+            if ifname == except_ifname:
+                continue
+
+            if 'addresses' in iface:
+                for a in iface['addresses']:
+                    ret.append(ipaddress.ip_interface(a))
+            if 'sub-interfaces' in iface:
+                for subid, sub_iface in iface['sub-interfaces'].items():
+                    sub_ifname = "%s.%d" % (ifname, subid)
+                    if sub_ifname == except_ifname:
+                        continue
+
+                    if 'addresses' in sub_iface:
+                        for a in sub_iface['addresses']:
+                            ret.append(ipaddress.ip_interface(a))
+    if 'loopbacks' in yaml:
+        for ifname, iface in yaml['loopbacks'].items():
+            if ifname == except_ifname:
+                continue
+
+            if 'addresses' in iface:
+                for a in iface['addresses']:
+                    ret.append(ipaddress.ip_interface(a))
+    if 'bridgedomains' in yaml:
+        for ifname, iface in yaml['bridgedomains'].items():
+            if ifname == except_ifname:
+                continue
+
+            if 'addresses' in iface:
+                for a in iface['addresses']:
+                    ret.append(ipaddress.ip_interface(a))
+
+    return ret
+
+def is_allowed(yaml, ifname, iface_addresses, ip_interface):
+    """ Returns True if there is at most one occurence of the ip_interface (an IPv4/IPv6 prefix+len)
+        in the entire config. That said, we need the 'iface_addresses' because VPP is a bit fickle in
+        this regard.
+
+        IP addresses from the same prefix/len can be added to a given interface (ie 192.0.2.1/24 and
+        192.0.2.2/24), but other than that, any prefix can not occur as a more-specific or less-specific
+        of any other interface.
+
+        So, we will allow:
+        - any ip_interface that is of equal network/len of existing one(s) _on the same interface_
+
+        And, we will reject
+        - any ip_interface that is a more specific of any existing one
+        - any ip_interface that is a less specific of any existing one
+
+        Examples:
+        vpp# set interface ip address loop0 192.0.2.1/24
+        vpp# set interface ip address loop0 192.0.2.2/24
+        vpp# set interface ip address loop0 192.0.2.1/29
+        set interface ip address: failed to add 192.0.2.1/29 on loop0 which conflicts with 192.0.2.1/24 for interface loop0
+        vpp# set interface ip address loop0 192.0.2.3/23
+        set interface ip address: failed to add 192.0.2.3/23 on loop0 which conflicts with 192.0.2.1/24 for interface loop0
+    """
+    ## print("input: (%s,%s)" % (iface_addresses, ip_interface))
+    all_other_addresses = get_all_addresses_except_ifname(yaml, ifname)
+    ## print("All IPs: %s" % all_other_addresses)
+
+    my_ip_network = ipaddress.ip_network(ip_interface, strict=False)
+
+    for ipi in all_other_addresses:
+        if ipi.version != my_ip_network.version:
+            continue
+
+        if ipaddress.ip_network(ipi, strict=False) == my_ip_network:
+            ## print("Same: %s == %s" % (ip_interface, ipi))
+            return False
+
+        if ipaddress.ip_network(ipi, strict=False).subnet_of(my_ip_network):
+            ## print("More: %s == %s" % (ip_interface, ipi))
+            return False
+
+        if my_ip_network.subnet_of(ipaddress.ip_network(ipi, strict=False)):
+            ## print("Less: %s == %s" % (ip_interface, ipi))
+            return False
+
+    for ip in iface_addresses:
+        ipi = ipaddress.ip_interface(ip)
+        if ipi.version != my_ip_network.version:
+            continue
+
+        if ipaddress.ip_network(ipi, strict=False) == my_ip_network:
+            ## print("iface same: %s == %s" % (ip_interface, ipi))
+            return True
+
+        if ipaddress.ip_network(ipi, strict=False).subnet_of(my_ip_network):
+            ## print("iface more: %s == %s" % (ip_interface, ipi))
+            return False
+
+        if my_ip_network.subnet_of(ipaddress.ip_network(ipi, strict=False)):
+            ## print("iface less: %s == %s" % (ip_interface, ipi))
+            return False
+
+    return True