Merge pull request #1731 from c-po/t578-container-backport

container: T578: backport podman from 1.4 development branch (equuleus)

1 files changed, 395 insertions, 0 deletions

diff --git a/src/conf_mode/container.py b/src/conf_mode/container.py
new file mode 100755
index 000000000..7567444db
--- /dev/null
+++ b/src/conf_mode/container.py
@@ -0,0 +1,395 @@
+#!/usr/bin/env python3
+#
+# Copyright (C) 2021-2022 VyOS maintainers and contributors
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License version 2 or later as
+# published by the Free Software Foundation.
+#
+# 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 os
+
+from ipaddress import ip_address
+from ipaddress import ip_network
+from time import sleep
+from json import dumps as json_write
+
+from vyos.base import Warning
+from vyos.config import Config
+from vyos.configdict import dict_merge
+from vyos.configdict import node_changed
+from vyos.util import call
+from vyos.util import cmd
+from vyos.util import run
+from vyos.util import write_file
+from vyos.template import inc_ip
+from vyos.template import is_ipv4
+from vyos.template import is_ipv6
+from vyos.template import render
+from vyos.xml import defaults
+from vyos import ConfigError
+from vyos import airbag
+airbag.enable()
+
+config_containers_registry = '/etc/containers/registries.conf'
+config_containers_storage = '/etc/containers/storage.conf'
+systemd_unit_path = '/run/systemd/system'
+
+def _cmd(command):
+    if os.path.exists('/tmp/vyos.container.debug'):
+        print(command)
+    return cmd(command)
+
+def network_exists(name):
+    # Check explicit name for network, returns True if network exists
+    c = _cmd(f'podman network ls --quiet --filter name=^{name}$')
+    return bool(c)
+
+# Common functions
+def get_config(config=None):
+    if config:
+        conf = config
+    else:
+        conf = Config()
+
+    base = ['container']
+    container = conf.get_config_dict(base, key_mangling=('-', '_'),
+                                     get_first_key=True, no_tag_node_value_mangle=True)
+    # We have gathered the dict representation of the CLI, but there are default
+    # options which we need to update into the dictionary retrived.
+    default_values = defaults(base)
+    # container base default values can not be merged here - remove and add them later
+    if 'name' in default_values:
+        del default_values['name']
+    container = dict_merge(default_values, container)
+
+    # Merge per-container default values
+    if 'name' in container:
+        default_values = defaults(base + ['name'])
+        if 'port' in default_values:
+            del default_values['port']
+        for name in container['name']:
+            container['name'][name] = dict_merge(default_values, container['name'][name])
+
+            # XXX: T2665: we can not safely rely on the defaults() when there are
+            # tagNodes in place, it is better to blend in the defaults manually.
+            if 'port' in container['name'][name]:
+                for port in container['name'][name]['port']:
+                    default_values = defaults(base + ['name', 'port'])
+                    container['name'][name]['port'][port] = dict_merge(
+                        default_values, container['name'][name]['port'][port])
+
+    # Delete container network, delete containers
+    tmp = node_changed(conf, base + ['network'])
+    if tmp: container.update({'network_remove' : tmp})
+
+    tmp = node_changed(conf, base + ['name'])
+    if tmp: container.update({'container_remove' : tmp})
+
+    return container
+
+def verify(container):
+    # bail out early - looks like removal from running config
+    if not container:
+        return None
+
+    # Add new container
+    if 'name' in container:
+        for name, container_config in container['name'].items():
+            # Container image is a mandatory option
+            if 'image' not in container_config:
+                raise ConfigError(f'Container image for "{name}" is mandatory!')
+
+            # Check if requested container image exists locally. If it does not
+            # exist locally - inform the user. This is required as there is a
+            # shared container image storage accross all VyOS images. A user can
+            # delete a container image from the system, boot into another version
+            # of VyOS and then it would fail to boot. This is to prevent any
+            # configuration error when container images are deleted from the
+            # global storage. A per image local storage would be a super waste
+            # of diskspace as there will be a full copy (up tu several GB/image)
+            # on upgrade. This is the "cheapest" and fastest solution in terms
+            # of image upgrade and deletion.
+            image = container_config['image']
+            if run(f'podman image exists {image}') != 0:
+                Warning(f'Image "{image}" used in container "{name}" does not exist '\
+                        f'locally. Please use "add container image {image}" to add it '\
+                        f'to the system! Container "{name}" will not be started!')
+
+            if 'network' in container_config:
+                if len(container_config['network']) > 1:
+                    raise ConfigError(f'Only one network can be specified for container "{name}"!')
+
+                # Check if the specified container network exists
+                network_name = list(container_config['network'])[0]
+                if network_name not in container.get('network', {}):
+                    raise ConfigError(f'Container network "{network_name}" does not exist!')
+
+                if 'address' in container_config['network'][network_name]:
+                    address = container_config['network'][network_name]['address']
+                    network = None
+                    if is_ipv4(address):
+                        network = [x for x in container['network'][network_name]['prefix'] if is_ipv4(x)][0]
+                    elif is_ipv6(address):
+                        network = [x for x in container['network'][network_name]['prefix'] if is_ipv6(x)][0]
+
+                    # Specified container IP address must belong to network prefix
+                    if ip_address(address) not in ip_network(network):
+                        raise ConfigError(f'Used container address "{address}" not in network "{network}"!')
+
+                    # We can not use the first IP address of a network prefix as this is used by podman
+                    if ip_address(address) == ip_network(network)[1]:
+                        raise ConfigError(f'IP address "{address}" can not be used for a container, '\
+                                          'reserved for the container engine!')
+
+            if 'device' in container_config:
+                for dev, dev_config in container_config['device'].items():
+                    if 'source' not in dev_config:
+                        raise ConfigError(f'Device "{dev}" has no source path configured!')
+
+                    if 'destination' not in dev_config:
+                        raise ConfigError(f'Device "{dev}" has no destination path configured!')
+
+                    source = dev_config['source']
+                    if not os.path.exists(source):
+                        raise ConfigError(f'Device "{dev}" source path "{source}" does not exist!')
+
+            if 'environment' in container_config:
+                for var, cfg in container_config['environment'].items():
+                    if 'value' not in cfg:
+                        raise ConfigError(f'Environment variable {var} has no value assigned!')
+
+            if 'volume' in container_config:
+                for volume, volume_config in container_config['volume'].items():
+                    if 'source' not in volume_config:
+                        raise ConfigError(f'Volume "{volume}" has no source path configured!')
+
+                    if 'destination' not in volume_config:
+                        raise ConfigError(f'Volume "{volume}" has no destination path configured!')
+
+                    source = volume_config['source']
+                    if not os.path.exists(source):
+                        raise ConfigError(f'Volume "{volume}" source path "{source}" does not exist!')
+
+            if 'port' in container_config:
+                for tmp in container_config['port']:
+                    if not {'source', 'destination'} <= set(container_config['port'][tmp]):
+                        raise ConfigError(f'Both "source" and "destination" must be specified for a port mapping!')
+
+            # If 'allow-host-networks' or 'network' not set.
+            if 'allow_host_networks' not in container_config and 'network' not in container_config:
+                raise ConfigError(f'Must either set "network" or "allow-host-networks" for container "{name}"!')
+
+            # Can not set both allow-host-networks and network at the same time
+            if {'allow_host_networks', 'network'} <= set(container_config):
+                raise ConfigError(f'"allow-host-networks" and "network" for "{name}" cannot be both configured at the same time!')
+
+    # Add new network
+    if 'network' in container:
+        for network, network_config in container['network'].items():
+            v4_prefix = 0
+            v6_prefix = 0
+            # If ipv4-prefix not defined for user-defined network
+            if 'prefix' not in network_config:
+                raise ConfigError(f'prefix for network "{network}" must be defined!')
+
+            for prefix in network_config['prefix']:
+                if is_ipv4(prefix): v4_prefix += 1
+                elif is_ipv6(prefix): v6_prefix += 1
+
+            if v4_prefix > 1:
+                raise ConfigError(f'Only one IPv4 prefix can be defined for network "{network}"!')
+            if v6_prefix > 1:
+                raise ConfigError(f'Only one IPv6 prefix can be defined for network "{network}"!')
+
+
+    # A network attached to a container can not be deleted
+    if {'network_remove', 'name'} <= set(container):
+        for network in container['network_remove']:
+            for container, container_config in container['name'].items():
+                if 'network' in container_config and network in container_config['network']:
+                    raise ConfigError(f'Can not remove network "{network}", used by container "{container}"!')
+
+    return None
+
+def generate_run_arguments(name, container_config):
+    image = container_config['image']
+    memory = container_config['memory']
+    shared_memory = container_config['shared_memory']
+    restart = container_config['restart']
+
+    # Add capability options. Should be in uppercase
+    cap_add = ''
+    if 'cap_add' in container_config:
+        for c in container_config['cap_add']:
+            c = c.upper()
+            c = c.replace('-', '_')
+            cap_add += f' --cap-add={c}'
+
+    # Add a host device to the container /dev/x:/dev/x
+    device = ''
+    if 'device' in container_config:
+        for dev, dev_config in container_config['device'].items():
+            source_dev = dev_config['source']
+            dest_dev = dev_config['destination']
+            device += f' --device={source_dev}:{dest_dev}'
+
+    # Check/set environment options "-e foo=bar"
+    env_opt = ''
+    if 'environment' in container_config:
+        for k, v in container_config['environment'].items():
+            env_opt += f" -e \"{k}={v['value']}\""
+
+    # Publish ports
+    port = ''
+    if 'port' in container_config:
+        protocol = ''
+        for portmap in container_config['port']:
+            protocol = container_config['port'][portmap]['protocol']
+            sport = container_config['port'][portmap]['source']
+            dport = container_config['port'][portmap]['destination']
+            port += f' -p {sport}:{dport}/{protocol}'
+
+    # Bind volume
+    volume = ''
+    if 'volume' in container_config:
+        for vol, vol_config in container_config['volume'].items():
+            svol = vol_config['source']
+            dvol = vol_config['destination']
+            volume += f' -v {svol}:{dvol}'
+
+    container_base_cmd = f'--detach --interactive --tty --replace {cap_add} ' \
+                         f'--memory {memory}m --shm-size {shared_memory}m --memory-swap 0 --restart {restart} ' \
+                         f'--name {name} {device} {port} {volume} {env_opt}'
+
+    if 'allow_host_networks' in container_config:
+        return f'{container_base_cmd} --net host {image}'
+
+    ip_param = ''
+    networks = ",".join(container_config['network'])
+    for network in container_config['network']:
+        if 'address' in container_config['network'][network]:
+            address = container_config['network'][network]['address']
+            ip_param = f'--ip {address}'
+
+    return f'{container_base_cmd} --net {networks} {ip_param} {image}'
+
+def generate(container):
+    # bail out early - looks like removal from running config
+    if not container:
+        if os.path.exists(config_containers_registry):
+            os.unlink(config_containers_registry)
+        if os.path.exists(config_containers_storage):
+            os.unlink(config_containers_storage)
+        return None
+
+    if 'network' in container:
+        for network, network_config in container['network'].items():
+            tmp = {
+                'cniVersion' : '0.4.0',
+                'name' : network,
+                'plugins' : [{
+                    'type': 'bridge',
+                    'bridge': f'cni-{network}',
+                    'isGateway': True,
+                    'ipMasq': False,
+                    'hairpinMode': False,
+                    'ipam' : {
+                        'type': 'host-local',
+                        'routes': [],
+                        'ranges' : [],
+                    },
+                }]
+            }
+
+            for prefix in network_config['prefix']:
+                net = [{'gateway' : inc_ip(prefix, 1), 'subnet' : prefix}]
+                tmp['plugins'][0]['ipam']['ranges'].append(net)
+
+                # install per address-family default orutes
+                default_route = '0.0.0.0/0'
+                if is_ipv6(prefix):
+                    default_route = '::/0'
+                tmp['plugins'][0]['ipam']['routes'].append({'dst': default_route})
+
+            write_file(f'/etc/cni/net.d/{network}.conflist', json_write(tmp, indent=2))
+
+    render(config_containers_registry, 'container/registries.conf.j2', container)
+    render(config_containers_storage, 'container/storage.conf.j2', container)
+
+    if 'name' in container:
+        for name, container_config in container['name'].items():
+            if 'disable' in container_config:
+                continue
+
+            file_path = os.path.join(systemd_unit_path, f'vyos-container-{name}.service')
+            run_args = generate_run_arguments(name, container_config)
+            render(file_path, 'container/systemd-unit.j2', {'name': name, 'run_args': run_args})
+
+    return None
+
+def apply(container):
+    # Delete old containers if needed. We can't delete running container
+    # Option "--force" allows to delete containers with any status
+    if 'container_remove' in container:
+        for name in container['container_remove']:
+            file_path = os.path.join(systemd_unit_path, f'vyos-container-{name}.service')
+            call(f'systemctl stop vyos-container-{name}.service')
+            if os.path.exists(file_path):
+                os.unlink(file_path)
+
+    call('systemctl daemon-reload')
+
+    # Delete old networks if needed
+    if 'network_remove' in container:
+        for network in container['network_remove']:
+            call(f'podman network rm {network}')
+            tmp = f'/etc/cni/net.d/{network}.conflist'
+            if os.path.exists(tmp):
+                os.unlink(tmp)
+
+    # Add container
+    disabled_new = False
+    if 'name' in container:
+        for name, container_config in container['name'].items():
+            image = container_config['image']
+
+            if run(f'podman image exists {image}') != 0:
+                # container image does not exist locally - user already got
+                # informed by a WARNING in verfiy() - bail out early
+                continue
+
+            if 'disable' in container_config:
+                # check if there is a container by that name running
+                tmp = _cmd('podman ps -a --format "{{.Names}}"')
+                if name in tmp:
+                    file_path = os.path.join(systemd_unit_path, f'vyos-container-{name}.service')
+                    call(f'systemctl stop vyos-container-{name}.service')
+                    if os.path.exists(file_path):
+                        disabled_new = True
+                        os.unlink(file_path)
+                continue
+
+            cmd(f'systemctl restart vyos-container-{name}.service')
+
+    if disabled_new:
+        call('systemctl daemon-reload')
+
+    return None
+
+if __name__ == '__main__':
+    try:
+        c = get_config()
+        verify(c)
+        generate(c)
+        apply(c)
+    except ConfigError as e:
+        print(e)
+        exit(1)