T5195: move helpers from vyos.validate to vyos.utils package

3 files changed, 266 insertions, 2 deletions

diff --git a/python/vyos/utils/__init__.py b/python/vyos/utils/__init__.py
index f2783113a..12ef2d3b8 100644
--- a/python/vyos/utils/__init__.py
+++ b/python/vyos/utils/__init__.py
@@ -13,6 +13,7 @@
 # You should have received a copy of the GNU Lesser General Public
 # License along with this library.  If not, see <http://www.gnu.org/licenses/>.
 
+from vyos.utils import assertion
 from vyos.utils import auth
 from vyos.utils import boot
 from vyos.utils import commit
diff --git a/python/vyos/utils/assertion.py b/python/vyos/utils/assertion.py
new file mode 100644
index 000000000..1aaa54dff
--- /dev/null
+++ b/python/vyos/utils/assertion.py
@@ -0,0 +1,81 @@
+# Copyright 2023 VyOS maintainers and contributors <maintainers@vyos.io>
+#
+# This library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
+#
+# This library 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
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this library.  If not, see <http://www.gnu.org/licenses/>.
+
+def assert_boolean(b):
+    if int(b) not in (0, 1):
+        raise ValueError(f'Value {b} out of range')
+
+def assert_range(value, lower=0, count=3):
+    if int(value, 16) not in range(lower, lower+count):
+        raise ValueError("Value out of range")
+
+def assert_list(s, l):
+    if s not in l:
+        o = ' or '.join([f'"{n}"' for n in l])
+        raise ValueError(f'state must be {o}, got {s}')
+
+def assert_number(n):
+    if not str(n).isnumeric():
+        raise ValueError(f'{n} must be a number')
+
+def assert_positive(n, smaller=0):
+    assert_number(n)
+    if int(n) < smaller:
+        raise ValueError(f'{n} is smaller than {smaller}')
+
+def assert_mtu(mtu, ifname):
+    assert_number(mtu)
+
+    import json
+    from vyos.utils.process import cmd
+    out = cmd(f'ip -j -d link show dev {ifname}')
+    # [{"ifindex":2,"ifname":"eth0","flags":["BROADCAST","MULTICAST","UP","LOWER_UP"],"mtu":1500,"qdisc":"pfifo_fast","operstate":"UP","linkmode":"DEFAULT","group":"default","txqlen":1000,"link_type":"ether","address":"08:00:27:d9:5b:04","broadcast":"ff:ff:ff:ff:ff:ff","promiscuity":0,"min_mtu":46,"max_mtu":16110,"inet6_addr_gen_mode":"none","num_tx_queues":1,"num_rx_queues":1,"gso_max_size":65536,"gso_max_segs":65535}]
+    parsed = json.loads(out)[0]
+    min_mtu = int(parsed.get('min_mtu', '0'))
+    # cur_mtu = parsed.get('mtu',0),
+    max_mtu = int(parsed.get('max_mtu', '0'))
+    cur_mtu = int(mtu)
+
+    if (min_mtu and cur_mtu < min_mtu) or cur_mtu < 68:
+        raise ValueError(f'MTU is too small for interface "{ifname}": {mtu} < {min_mtu}')
+    if (max_mtu and cur_mtu > max_mtu) or cur_mtu > 65536:
+        raise ValueError(f'MTU is too small for interface "{ifname}": {mtu} > {max_mtu}')
+
+def assert_mac(m):
+    split = m.split(':')
+    size = len(split)
+
+    # a mac address consits out of 6 octets
+    if size != 6:
+        raise ValueError(f'wrong number of MAC octets ({size}): {m}')
+
+    octets = []
+    try:
+        for octet in split:
+            octets.append(int(octet, 16))
+    except ValueError:
+        raise ValueError(f'invalid hex number "{octet}" in : {m}')
+
+    # validate against the first mac address byte if it's a multicast
+    # address
+    if octets[0] & 1:
+        raise ValueError(f'{m} is a multicast MAC address')
+
+    # overall mac address is not allowed to be 00:00:00:00:00:00
+    if sum(octets) == 0:
+        raise ValueError('00:00:00:00:00:00 is not a valid MAC address')
+
+    if octets[:5] == (0, 0, 94, 0, 1):
+        raise ValueError(f'{m} is a VRRP MAC address')
diff --git a/python/vyos/utils/network.py b/python/vyos/utils/network.py
index 3786caf26..3f9a3ef4b 100644
--- a/python/vyos/utils/network.py
+++ b/python/vyos/utils/network.py
@@ -13,7 +13,15 @@
 # You should have received a copy of the GNU Lesser General Public
 # License along with this library.  If not, see <http://www.gnu.org/licenses/>.
 
-import os
+def _are_same_ip(one, two):
+    from socket import AF_INET
+    from socket import AF_INET6
+    from socket import inet_pton
+    from vyos.template import is_ipv4
+    # compare the binary representation of the IP
+    f_one = AF_INET if is_ipv4(one) else AF_INET6
+    s_two = AF_INET if is_ipv4(two) else AF_INET6
+    return inet_pton(f_one, one) == inet_pton(f_one, two)
 
 def get_protocol_by_name(protocol_name):
     """Get protocol number by protocol name
@@ -48,6 +56,7 @@ def get_interface_config(interface):
     """ Returns the used encapsulation protocol for given interface.
         If interface does not exist, None is returned.
     """
+    import os
     if not os.path.exists(f'/sys/class/net/{interface}'):
         return None
     from json import loads
@@ -59,6 +68,7 @@ def get_interface_address(interface):
     """ Returns the used encapsulation protocol for given interface.
         If interface does not exist, None is returned.
     """
+    import os
     if not os.path.exists(f'/sys/class/net/{interface}'):
         return None
     from json import loads
@@ -85,7 +95,6 @@ def get_interface_namespace(iface):
             if iface == tmp["ifname"]:
                 return netns
 
-
 def is_wwan_connected(interface):
     """ Determine if a given WWAN interface, e.g. wwan0 is connected to the
     carrier network or not """
@@ -110,6 +119,7 @@ def is_wwan_connected(interface):
 
 def get_bridge_fdb(interface):
     """ Returns the forwarding database entries for a given interface """
+    import os
     if not os.path.exists(f'/sys/class/net/{interface}'):
         return None
     from json import loads
@@ -211,3 +221,175 @@ def is_listen_port_bind_service(port: int, service: str) -> bool:
         if service == pid_name and port == pid_port:
             return True
     return False
+
+def is_ipv6_link_local(addr):
+    """ Check if addrsss is an IPv6 link-local address. Returns True/False """
+    from ipaddress import ip_interface
+    from vyos.template import is_ipv6
+    addr = addr.split('%')[0]
+    if is_ipv6(addr):
+        if ip_interface(addr).is_link_local:
+            return True
+
+    return False
+
+def is_addr_assigned(ip_address, vrf=None) -> bool:
+    """ Verify if the given IPv4/IPv6 address is assigned to any interface """
+    from netifaces import interfaces
+    from vyos.utils.network import get_interface_config
+    from vyos.utils.dict import dict_search
+
+    for interface in interfaces():
+        # Check if interface belongs to the requested VRF, if this is not the
+        # case there is no need to proceed with this data set - continue loop
+        # with next element
+        tmp = get_interface_config(interface)
+        if dict_search('master', tmp) != vrf:
+            continue
+
+        if is_intf_addr_assigned(interface, ip_address):
+            return True
+
+    return False
+
+def is_intf_addr_assigned(intf, address) -> bool:
+    """
+    Verify if the given IPv4/IPv6 address is assigned to specific interface.
+    It can check both a single IP address (e.g. 192.0.2.1 or a assigned CIDR
+    address 192.0.2.1/24.
+    """
+    from vyos.template import is_ipv4
+
+    from netifaces import ifaddresses
+    from netifaces import AF_INET
+    from netifaces import AF_INET6
+
+    # check if the requested address type is configured at all
+    # {
+    # 17: [{'addr': '08:00:27:d9:5b:04', 'broadcast': 'ff:ff:ff:ff:ff:ff'}],
+    # 2:  [{'addr': '10.0.2.15', 'netmask': '255.255.255.0', 'broadcast': '10.0.2.255'}],
+    # 10: [{'addr': 'fe80::a00:27ff:fed9:5b04%eth0', 'netmask': 'ffff:ffff:ffff:ffff::'}]
+    # }
+    try:
+        addresses = ifaddresses(intf)
+    except ValueError as e:
+        print(e)
+        return False
+
+    # determine IP version (AF_INET or AF_INET6) depending on passed address
+    addr_type = AF_INET if is_ipv4(address) else AF_INET6
+
+    # Check every IP address on this interface for a match
+    netmask = None
+    if '/' in address:
+        address, netmask = address.split('/')
+    for ip in addresses.get(addr_type, []):
+        # ip can have the interface name in the 'addr' field, we need to remove it
+        # {'addr': 'fe80::a00:27ff:fec5:f821%eth2', 'netmask': 'ffff:ffff:ffff:ffff::'}
+        ip_addr = ip['addr'].split('%')[0]
+
+        if not _are_same_ip(address, ip_addr):
+            continue
+
+        # we do not have a netmask to compare against, they are the same
+        if not netmask:
+            return True
+
+        prefixlen = ''
+        if is_ipv4(ip_addr):
+            prefixlen = sum([bin(int(_)).count('1') for _ in ip['netmask'].split('.')])
+        else:
+            prefixlen = sum([bin(int(_,16)).count('1') for _ in ip['netmask'].split('/')[0].split(':') if _])
+
+        if str(prefixlen) == netmask:
+            return True
+
+    return False
+
+def is_loopback_addr(addr):
+    """ Check if supplied IPv4/IPv6 address is a loopback address """
+    from ipaddress import ip_address
+    return ip_address(addr).is_loopback
+
+def is_wireguard_key_pair(private_key: str, public_key:str) -> bool:
+    """
+     Checks if public/private keys are keypair
+    :param private_key: Wireguard private key
+    :type private_key: str
+    :param public_key: Wireguard public key
+    :type public_key: str
+    :return: If public/private keys are keypair returns True else False
+    :rtype: bool
+    """
+    from vyos.utils.process import cmd
+    gen_public_key = cmd('wg pubkey', input=private_key)
+    if gen_public_key == public_key:
+        return True
+    else:
+        return False
+
+def is_subnet_connected(subnet, primary=False):
+    """
+    Verify is the given IPv4/IPv6 subnet is connected to any interface on this
+    system.
+
+    primary check if the subnet is reachable via the primary IP address of this
+    interface, or in other words has a broadcast address configured. ISC DHCP
+    for instance will complain if it should listen on non broadcast interfaces.
+
+    Return True/False
+    """
+    from ipaddress import ip_address
+    from ipaddress import ip_network
+
+    from netifaces import ifaddresses
+    from netifaces import interfaces
+    from netifaces import AF_INET
+    from netifaces import AF_INET6
+
+    from vyos.template import is_ipv6
+
+    # determine IP version (AF_INET or AF_INET6) depending on passed address
+    addr_type = AF_INET
+    if is_ipv6(subnet):
+        addr_type = AF_INET6
+
+    for interface in interfaces():
+        # check if the requested address type is configured at all
+        if addr_type not in ifaddresses(interface).keys():
+            continue
+
+        # An interface can have multiple addresses, but some software components
+        # only support the primary address :(
+        if primary:
+            ip = ifaddresses(interface)[addr_type][0]['addr']
+            if ip_address(ip) in ip_network(subnet):
+                return True
+        else:
+            # Check every assigned IP address if it is connected to the subnet
+            # in question
+            for ip in ifaddresses(interface)[addr_type]:
+                # remove interface extension (e.g. %eth0) that gets thrown on the end of _some_ addrs
+                addr = ip['addr'].split('%')[0]
+                if ip_address(addr) in ip_network(subnet):
+                    return True
+
+    return False
+
+def is_afi_configured(interface, afi):
+    """ Check if given address family is configured, or in other words - an IP
+    address is assigned to the interface. """
+    from netifaces import ifaddresses
+    from netifaces import AF_INET
+    from netifaces import AF_INET6
+
+    if afi not in [AF_INET, AF_INET6]:
+        raise ValueError('Address family must be in [AF_INET, AF_INET6]')
+
+    try:
+        addresses = ifaddresses(interface)
+    except ValueError as e:
+        print(e)
+        return False
+
+    return afi in addresses