74d8b4a6be
* Support for Control Plane ACL's for Multi-asic Platforms.
Following changes were done:
1) Moved from using blocking listen() on Config DB to the select() model
via python-swsscommon since we have to wait on event from multiple
config db's
2) Since python-swsscommon is not available on host added libswsscommon and python-swsscommon
and dependent packages in the base image (host enviroment)
3) Made iptables programmed in all namespace using ip netns exec
Signed-off-by: Abhishek Dosi <abdosi@microsoft.com>
* Address Review Comments
Signed-off-by: Abhishek Dosi <abdosi@microsoft.com>
* Fix Review Comments
* Fix Comments
* Added Change for Multi-asic to have iptables
rules to accept internal docker tcp/udp traffic
needed for syslog and redis-tcp connection.
Signed-off-by: Abhishek Dosi <abdosi@microsoft.com>
* Fix Review Comments
* Added more comments on logic.
* Fixed all warning/errors reported by http://pep8online.com/
other than line > 80 characters.
* Fix Comment
Signed-off-by: Abhishek Dosi <abdosi@microsoft.com>
* Verified with swsscommon package. Fix issue for single asic platforms.
* Moved to new python package
* Address Review Comments.
Signed-off-by: Abhishek Dosi <abdosi@microsoft.com>
* Address Review Comments.
509 lines
26 KiB
Python
Executable File
509 lines
26 KiB
Python
Executable File
#!/usr/bin/env python
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#
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# caclmgrd
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#
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# Control plane ACL manager daemon for SONiC
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#
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# Upon starting, this daemon reads control plane ACL tables and rules from
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# Config DB, converts the rules into iptables rules and installs the iptables
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# rules. The daemon then indefintely listens for notifications from Config DB
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# and updates iptables rules if control plane ACL configuration has changed.
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#
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try:
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import ipaddress
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import os
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import subprocess
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import sys
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import syslog
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from sonic_py_common import device_info
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from swsscommon import swsscommon
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from swsssdk import SonicDBConfig, ConfigDBConnector
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except ImportError as err:
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raise ImportError("%s - required module not found" % str(err))
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VERSION = "1.0"
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SYSLOG_IDENTIFIER = "caclmgrd"
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# ========================== Syslog wrappers ==========================
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def log_info(msg):
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syslog.openlog(SYSLOG_IDENTIFIER)
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syslog.syslog(syslog.LOG_INFO, msg)
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syslog.closelog()
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def log_warning(msg):
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syslog.openlog(SYSLOG_IDENTIFIER)
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syslog.syslog(syslog.LOG_WARNING, msg)
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syslog.closelog()
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def log_error(msg):
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syslog.openlog(SYSLOG_IDENTIFIER)
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syslog.syslog(syslog.LOG_ERR, msg)
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syslog.closelog()
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# ========================== Helper Functions =========================
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def _ip_prefix_in_key(key):
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"""
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Function to check if IP prefix is present in a Redis database key.
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If it is present, then the key will be a tuple. Otherwise, the
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key will be a string.
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"""
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return (isinstance(key, tuple))
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# ============================== Classes ==============================
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class ControlPlaneAclManager(object):
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"""
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Class which reads control plane ACL tables and rules from Config DB,
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translates them into equivalent iptables commands and runs those
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commands in order to apply the control plane ACLs.
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Attributes:
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config_db: Handle to Config Redis database via SwSS SDK
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"""
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ACL_TABLE = "ACL_TABLE"
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ACL_RULE = "ACL_RULE"
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ACL_TABLE_TYPE_CTRLPLANE = "CTRLPLANE"
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# To specify a port range instead of a single port, use iptables format:
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# separate start and end ports with a colon, e.g., "1000:2000"
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ACL_SERVICES = {
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"NTP": {
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"ip_protocols": ["udp"],
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"dst_ports": ["123"]
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},
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"SNMP": {
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"ip_protocols": ["tcp", "udp"],
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"dst_ports": ["161"]
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},
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"SSH": {
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"ip_protocols": ["tcp"],
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"dst_ports": ["22"]
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}
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}
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def __init__(self):
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SonicDBConfig.load_sonic_global_db_config()
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self.config_db_map = {}
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self.iptables_cmd_ns_prefix = {}
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self.config_db_map[''] = ConfigDBConnector(use_unix_socket_path=True, namespace='')
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self.config_db_map[''].connect()
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self.iptables_cmd_ns_prefix[''] = ""
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self.namespace_mgmt_ip = self.get_namespace_mgmt_ip(self.iptables_cmd_ns_prefix[''], '')
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self.namespace_docker_mgmt_ip = {}
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namespaces = device_info.get_all_namespaces()
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for front_asic_namespace in namespaces['front_ns']:
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self.config_db_map[front_asic_namespace] = ConfigDBConnector(use_unix_socket_path=True, namespace=front_asic_namespace)
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self.config_db_map[front_asic_namespace].connect()
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self.iptables_cmd_ns_prefix[front_asic_namespace] = "ip netns exec " + front_asic_namespace + " "
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self.namespace_docker_mgmt_ip[front_asic_namespace] = self.get_namespace_mgmt_ip(self.iptables_cmd_ns_prefix[front_asic_namespace],
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front_asic_namespace)
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for back_asic_namespace in namespaces['back_ns']:
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self.iptables_cmd_ns_prefix[back_asic_namespace] = "ip netns exec " + back_asic_namespace + " "
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self.namespace_docker_mgmt_ip[back_asic_namespace] = self.get_namespace_mgmt_ip(self.iptables_cmd_ns_prefix[back_asic_namespace],
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back_asic_namespace)
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def get_namespace_mgmt_ip(self, iptable_ns_cmd_prefix, namespace):
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ip_address_get_command = iptable_ns_cmd_prefix + "ip -4 -o addr show " + ("eth0" if namespace else "docker0") +\
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" | awk '{print $4}' | cut -d'/' -f1 | head -1"
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return self.run_commands([ip_address_get_command])
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def run_commands(self, commands):
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"""
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Given a list of shell commands, run them in order
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Args:
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commands: List of strings, each string is a shell command
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"""
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for cmd in commands:
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proc = subprocess.Popen(cmd, shell=True, stdout=subprocess.PIPE)
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(stdout, stderr) = proc.communicate()
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if proc.returncode != 0:
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log_error("Error running command '{}'".format(cmd))
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elif stdout:
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return stdout.rstrip('\n')
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def parse_int_to_tcp_flags(self, hex_value):
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tcp_flags_str = ""
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if hex_value & 0x01:
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tcp_flags_str += "FIN,"
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if hex_value & 0x02:
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tcp_flags_str += "SYN,"
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if hex_value & 0x04:
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tcp_flags_str += "RST,"
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if hex_value & 0x08:
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tcp_flags_str += "PSH,"
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if hex_value & 0x10:
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tcp_flags_str += "ACK,"
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if hex_value & 0x20:
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tcp_flags_str += "URG,"
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# iptables doesn't handle the flags below now. It has some special keys for it:
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# --ecn-tcp-cwr This matches if the TCP ECN CWR (Congestion Window Received) bit is set.
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# --ecn-tcp-ece This matches if the TCP ECN ECE (ECN Echo) bit is set.
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# if hex_value & 0x40:
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# tcp_flags_str += "ECE,"
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# if hex_value & 0x80:
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# tcp_flags_str += "CWR,"
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# Delete the trailing comma
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tcp_flags_str = tcp_flags_str[:-1]
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return tcp_flags_str
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def generate_block_ip2me_traffic_iptables_commands(self, namespace):
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INTERFACE_TABLE_NAME_LIST = [
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"LOOPBACK_INTERFACE",
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"MGMT_INTERFACE",
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"VLAN_INTERFACE",
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"PORTCHANNEL_INTERFACE",
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"INTERFACE"
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]
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block_ip2me_cmds = []
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# Add iptables rules to drop all packets destined for peer-to-peer interface IP addresses
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for iface_table_name in INTERFACE_TABLE_NAME_LIST:
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iface_table = self.config_db_map[namespace].get_table(iface_table_name)
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if iface_table:
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for key, _ in iface_table.iteritems():
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if not _ip_prefix_in_key(key):
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continue
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iface_name, iface_cidr = key
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ip_ntwrk = ipaddress.ip_network(iface_cidr, strict=False)
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# For VLAN interfaces, the IP address we want to block is the default gateway (i.e.,
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# the first available host IP address of the VLAN subnet)
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ip_addr = next(ip_ntwrk.hosts()) if iface_table_name == "VLAN_INTERFACE" else ip_ntwrk.network_address
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if isinstance(ip_ntwrk, ipaddress.IPv4Network):
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block_ip2me_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "iptables -A INPUT -d {}/{} -j DROP".format(ip_addr, ip_ntwrk.max_prefixlen))
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elif isinstance(ip_ntwrk, ipaddress.IPv6Network):
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block_ip2me_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "ip6tables -A INPUT -d {}/{} -j DROP".format(ip_addr, ip_ntwrk.max_prefixlen))
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else:
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log_warning("Unrecognized IP address type on interface '{}': {}".format(iface_name, ip_ntwrk))
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return block_ip2me_cmds
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def generate_allow_internal_docker_ip_traffic_commands(self, namespace):
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allow_internal_docker_ip_cmds = []
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if namespace:
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# For namespace docker allow all tcp/udp traffic from host docker bridge to its eth0 management ip
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allow_internal_docker_ip_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "iptables -A INPUT -p tcp -s {} -d {} -j ACCEPT".format
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(self.namespace_mgmt_ip, self.namespace_docker_mgmt_ip[namespace]))
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allow_internal_docker_ip_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "iptables -A INPUT -p udp -s {} -d {} -j ACCEPT".format
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(self.namespace_mgmt_ip, self.namespace_docker_mgmt_ip[namespace]))
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else:
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# In host allow all tcp/udp traffic from namespace docker eth0 management ip to host docker bridge
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for docker_mgmt_ip in self.namespace_docker_mgmt_ip.values():
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allow_internal_docker_ip_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "iptables -A INPUT -p tcp -s {} -d {} -j ACCEPT".format
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(docker_mgmt_ip, self.namespace_mgmt_ip))
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allow_internal_docker_ip_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "iptables -A INPUT -p udp -s {} -d {} -j ACCEPT".format
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(docker_mgmt_ip, self.namespace_mgmt_ip))
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return allow_internal_docker_ip_cmds
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def is_rule_ipv4(self, rule_props):
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if (("SRC_IP" in rule_props and rule_props["SRC_IP"]) or
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("DST_IP" in rule_props and rule_props["DST_IP"])):
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return True
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else:
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return False
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def is_rule_ipv6(self, rule_props):
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if (("SRC_IPV6" in rule_props and rule_props["SRC_IPV6"]) or
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("DST_IPV6" in rule_props and rule_props["DST_IPV6"])):
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return True
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else:
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return False
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def get_acl_rules_and_translate_to_iptables_commands(self, namespace):
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"""
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Retrieves current ACL tables and rules from Config DB, translates
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control plane ACLs into a list of iptables commands that can be run
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in order to install ACL rules.
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Returns:
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A list of strings, each string is an iptables shell command
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"""
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iptables_cmds = []
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# First, add iptables commands to set default policies to accept all
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# traffic. In case we are connected remotely, the connection will not
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# drop when we flush the current rules
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "iptables -P INPUT ACCEPT")
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "iptables -P FORWARD ACCEPT")
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "iptables -P OUTPUT ACCEPT")
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# Add iptables command to flush the current rules
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "iptables -F")
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# Add iptables command to delete all non-default chains
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "iptables -X")
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# Add same set of commands for ip6tables
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "ip6tables -P INPUT ACCEPT")
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "ip6tables -P FORWARD ACCEPT")
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "ip6tables -P OUTPUT ACCEPT")
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "ip6tables -F")
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "ip6tables -X")
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# Add iptables/ip6tables commands to allow all traffic from localhost
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "iptables -A INPUT -s 127.0.0.1 -i lo -j ACCEPT")
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "ip6tables -A INPUT -s ::1 -i lo -j ACCEPT")
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# Add iptables commands to allow internal docker traffic
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iptables_cmds += self.generate_allow_internal_docker_ip_traffic_commands(namespace)
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# Add iptables/ip6tables commands to allow all incoming packets from established
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# connections or new connections which are related to established connections
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "iptables -A INPUT -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT")
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "ip6tables -A INPUT -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT")
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# Add iptables/ip6tables commands to allow bidirectional ICMPv4 ping and traceroute
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# TODO: Support processing ICMPv4 service ACL rules, and remove this blanket acceptance
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "iptables -A INPUT -p icmp --icmp-type echo-request -j ACCEPT")
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "iptables -A INPUT -p icmp --icmp-type echo-reply -j ACCEPT")
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "iptables -A INPUT -p icmp --icmp-type destination-unreachable -j ACCEPT")
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "iptables -A INPUT -p icmp --icmp-type time-exceeded -j ACCEPT")
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# Add iptables/ip6tables commands to allow bidirectional ICMPv6 ping and traceroute
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# TODO: Support processing ICMPv6 service ACL rules, and remove this blanket acceptance
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "ip6tables -A INPUT -p icmpv6 --icmpv6-type echo-request -j ACCEPT")
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "ip6tables -A INPUT -p icmpv6 --icmpv6-type echo-reply -j ACCEPT")
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "ip6tables -A INPUT -p icmpv6 --icmpv6-type destination-unreachable -j ACCEPT")
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "ip6tables -A INPUT -p icmpv6 --icmpv6-type time-exceeded -j ACCEPT")
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# Add iptables/ip6tables commands to allow all incoming Neighbor Discovery Protocol (NDP) NS/NA/RS/RA messages
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# TODO: Support processing NDP service ACL rules, and remove this blanket acceptance
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "ip6tables -A INPUT -p icmpv6 --icmpv6-type neighbor-solicitation -j ACCEPT")
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "ip6tables -A INPUT -p icmpv6 --icmpv6-type neighbor-advertisement -j ACCEPT")
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "ip6tables -A INPUT -p icmpv6 --icmpv6-type router-solicitation -j ACCEPT")
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "ip6tables -A INPUT -p icmpv6 --icmpv6-type router-advertisement -j ACCEPT")
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# Add iptables/ip6tables commands to allow all incoming IPv4 DHCP packets
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "iptables -A INPUT -p udp --dport 67:68 -j ACCEPT")
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "ip6tables -A INPUT -p udp --dport 67:68 -j ACCEPT")
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# Add iptables/ip6tables commands to allow all incoming IPv6 DHCP packets
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "iptables -A INPUT -p udp --dport 546:547 -j ACCEPT")
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "ip6tables -A INPUT -p udp --dport 546:547 -j ACCEPT")
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# Add iptables/ip6tables commands to allow all incoming BGP traffic
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# TODO: Determine BGP ACLs based on configured device sessions, and remove this blanket acceptance
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "iptables -A INPUT -p tcp --dport 179 -j ACCEPT")
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "iptables -A INPUT -p tcp --sport 179 -j ACCEPT")
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "ip6tables -A INPUT -p tcp --dport 179 -j ACCEPT")
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iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "ip6tables -A INPUT -p tcp --sport 179 -j ACCEPT")
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# Get current ACL tables and rules from Config DB
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self._tables_db_info = self.config_db_map[namespace].get_table(self.ACL_TABLE)
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self._rules_db_info = self.config_db_map[namespace].get_table(self.ACL_RULE)
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num_ctrl_plane_acl_rules = 0
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# Walk the ACL tables
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for (table_name, table_data) in self._tables_db_info.iteritems():
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table_ip_version = None
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# Ignore non-control-plane ACL tables
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if table_data["type"] != self.ACL_TABLE_TYPE_CTRLPLANE:
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continue
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acl_services = table_data["services"]
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for acl_service in acl_services:
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if acl_service not in self.ACL_SERVICES:
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log_warning("Ignoring control plane ACL '{}' with unrecognized service '{}'"
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.format(table_name, acl_service))
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continue
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log_info("Translating ACL rules for control plane ACL '{}' (service: '{}')"
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.format(table_name, acl_service))
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# Obtain default IP protocol(s) and destination port(s) for this service
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ip_protocols = self.ACL_SERVICES[acl_service]["ip_protocols"]
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dst_ports = self.ACL_SERVICES[acl_service]["dst_ports"]
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acl_rules = {}
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for ((rule_table_name, rule_id), rule_props) in self._rules_db_info.iteritems():
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if rule_table_name == table_name:
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if not rule_props:
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log_warning("rule_props for rule_id {} empty or null!".format(rule_id))
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continue
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try:
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acl_rules[rule_props["PRIORITY"]] = rule_props
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except KeyError:
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log_error("rule_props for rule_id {} does not have key 'PRIORITY'!".format(rule_id))
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continue
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# If we haven't determined the IP version for this ACL table yet,
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# try to do it now. We attempt to determine heuristically based on
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# whether the src or dst IP of this rule is an IPv4 or IPv6 address.
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if not table_ip_version:
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if self.is_rule_ipv6(rule_props):
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table_ip_version = 6
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elif self.is_rule_ipv4(rule_props):
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table_ip_version = 4
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if (self.is_rule_ipv6(rule_props) and (table_ip_version == 4)):
|
|
log_error("CtrlPlane ACL table {} is a IPv4 based table and rule {} is a IPV6 rule! Ignoring rule."
|
|
.format(table_name, rule_id))
|
|
acl_rules.pop(rule_props["PRIORITY"])
|
|
elif (self.is_rule_ipv4(rule_props) and (table_ip_version == 6)):
|
|
log_error("CtrlPlane ACL table {} is a IPv6 based table and rule {} is a IPV4 rule! Ignroing rule."
|
|
.format(table_name, rule_id))
|
|
acl_rules.pop(rule_props["PRIORITY"])
|
|
|
|
# If we were unable to determine whether this ACL table contains
|
|
# IPv4 or IPv6 rules, log a message and skip processing this table.
|
|
if not table_ip_version:
|
|
log_warning("Unable to determine if ACL table '{}' contains IPv4 or IPv6 rules. Skipping table..."
|
|
.format(table_name))
|
|
continue
|
|
|
|
# For each ACL rule in this table (in descending order of priority)
|
|
for priority in sorted(acl_rules.iterkeys(), reverse=True):
|
|
rule_props = acl_rules[priority]
|
|
|
|
if "PACKET_ACTION" not in rule_props:
|
|
log_error("ACL rule does not contain PACKET_ACTION property")
|
|
continue
|
|
|
|
# Apply the rule to the default protocol(s) for this ACL service
|
|
for ip_protocol in ip_protocols:
|
|
for dst_port in dst_ports:
|
|
rule_cmd = "ip6tables" if table_ip_version == 6 else "iptables"
|
|
rule_cmd += " -A INPUT -p {}".format(ip_protocol)
|
|
|
|
if "SRC_IPV6" in rule_props and rule_props["SRC_IPV6"]:
|
|
rule_cmd += " -s {}".format(rule_props["SRC_IPV6"])
|
|
elif "SRC_IP" in rule_props and rule_props["SRC_IP"]:
|
|
rule_cmd += " -s {}".format(rule_props["SRC_IP"])
|
|
|
|
rule_cmd += " --dport {}".format(dst_port)
|
|
|
|
# If there are TCP flags present and ip protocol is TCP, append them
|
|
if ip_protocol == "tcp" and "TCP_FLAGS" in rule_props and rule_props["TCP_FLAGS"]:
|
|
tcp_flags, tcp_flags_mask = rule_props["TCP_FLAGS"].split("/")
|
|
|
|
tcp_flags = int(tcp_flags, 16)
|
|
tcp_flags_mask = int(tcp_flags_mask, 16)
|
|
|
|
if tcp_flags_mask > 0:
|
|
rule_cmd += " --tcp-flags {mask} {flags}".format(mask=self.parse_int_to_tcp_flags(tcp_flags_mask), flags=self.parse_int_to_tcp_flags(tcp_flags))
|
|
|
|
# Append the packet action as the jump target
|
|
rule_cmd += " -j {}".format(rule_props["PACKET_ACTION"])
|
|
|
|
iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + rule_cmd)
|
|
num_ctrl_plane_acl_rules += 1
|
|
|
|
# Add iptables commands to block ip2me traffic
|
|
iptables_cmds += self.generate_block_ip2me_traffic_iptables_commands(namespace)
|
|
|
|
# Add iptables/ip6tables commands to allow all incoming packets with TTL of 0 or 1
|
|
# This allows the device to respond to tools like tcptraceroute
|
|
iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "iptables -A INPUT -m ttl --ttl-lt 2 -j ACCEPT")
|
|
iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "ip6tables -A INPUT -p tcp -m hl --hl-lt 2 -j ACCEPT")
|
|
|
|
# Finally, if the device has control plane ACLs configured,
|
|
# add iptables/ip6tables commands to drop all other incoming packets
|
|
if num_ctrl_plane_acl_rules > 0:
|
|
iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "iptables -A INPUT -j DROP")
|
|
iptables_cmds.append(self.iptables_cmd_ns_prefix[namespace] + "ip6tables -A INPUT -j DROP")
|
|
|
|
return iptables_cmds
|
|
|
|
def update_control_plane_acls(self, namespace):
|
|
"""
|
|
Convenience wrapper which retrieves current ACL tables and rules from
|
|
Config DB, translates control plane ACLs into a list of iptables
|
|
commands and runs them.
|
|
"""
|
|
iptables_cmds = self.get_acl_rules_and_translate_to_iptables_commands(namespace)
|
|
log_info("Issuing the following iptables commands:")
|
|
for cmd in iptables_cmds:
|
|
log_info(" " + cmd)
|
|
|
|
self.run_commands(iptables_cmds)
|
|
|
|
def run(self):
|
|
# Select Time-out for 10 Seconds
|
|
SELECT_TIMEOUT_MS = 1000 * 10
|
|
|
|
# Initlaize Global config that loads all database*.json
|
|
if device_info.is_multi_npu():
|
|
swsscommon.SonicDBConfig.initializeGlobalConfig()
|
|
|
|
# Create the Select object
|
|
sel = swsscommon.Select()
|
|
# Map of Namespace <--> susbcriber table's object
|
|
config_db_subscriber_table_map = {}
|
|
|
|
# Loop through all asic namespaces (if present) and host (namespace='')
|
|
for namespace in self.config_db_map.keys():
|
|
# Unconditionally update control plane ACLs once at start on given namespace
|
|
self.update_control_plane_acls(namespace)
|
|
# Connect to Config DB of given namespace
|
|
acl_db_connector = swsscommon.DBConnector("CONFIG_DB", 0, False, namespace)
|
|
# Subscribe to notifications when ACL tables changes
|
|
subscribe_acl_table = swsscommon.SubscriberStateTable(acl_db_connector, swsscommon.CFG_ACL_TABLE_TABLE_NAME)
|
|
# Subscribe to notifications when ACL rule tables changes
|
|
subscribe_acl_rule_table = swsscommon.SubscriberStateTable(acl_db_connector, swsscommon.CFG_ACL_RULE_TABLE_NAME)
|
|
# Add both tables to the selectable object
|
|
sel.addSelectable(subscribe_acl_table)
|
|
sel.addSelectable(subscribe_acl_rule_table)
|
|
# Update the map
|
|
config_db_subscriber_table_map[namespace] = []
|
|
config_db_subscriber_table_map[namespace].append(subscribe_acl_table)
|
|
config_db_subscriber_table_map[namespace].append(subscribe_acl_rule_table)
|
|
|
|
# Loop on select to see if any event happen on config db of any namespace
|
|
while True:
|
|
(state, c) = sel.select(SELECT_TIMEOUT_MS)
|
|
# Continue if select is timeout or selectable object is not return
|
|
if state != swsscommon.Select.OBJECT:
|
|
continue
|
|
# Get the corresponding namespace from selectable object
|
|
namespace = c.getDbNamespace()
|
|
# Pop data of both Subscriber Table object of namespace that got config db acl table event
|
|
for table in config_db_subscriber_table_map[namespace]:
|
|
table.pop()
|
|
# Update the Control Plane ACL of the namespace that got config db acl table event
|
|
self.update_control_plane_acls(namespace)
|
|
|
|
# ============================= Functions =============================
|
|
|
|
|
|
def main():
|
|
log_info("Starting up...")
|
|
|
|
if not os.geteuid() == 0:
|
|
log_error("Must be root to run this daemon")
|
|
print "Error: Must be root to run this daemon"
|
|
sys.exit(1)
|
|
|
|
# Instantiate a ControlPlaneAclManager object
|
|
caclmgr = ControlPlaneAclManager()
|
|
caclmgr.run()
|
|
|
|
|
|
if __name__ == "__main__":
|
|
main()
|