FastNetMon 也可以结合 BGP 协议,打造自动化的抗 DDoS 安全防御系统。当发现受到攻击的时候,通过在 BGP 上宣告 blocked 受到攻击的 IP 地址。从而将攻击转移到其他地点,保证本地的其他服务不受到 DDoS 攻击的影响。

测试环境:Centos7

  • 安装 FastNetMon

官网:https://fastnetmon.com/install/

    wget https://raw.githubusercontent.com/pavel-odintsov/fastnetmon/master/src/fastnetmon_install.pl -Ofastnetmon_install.pl 
    sudo perl fastnetmon_install.pl --do-not-track-me
  • 使用 pf\_ring 作为 FastNetMon 的抓包引擎

FastNetMon 在安装的时候,已经安装了 pf\_ring 。
如果有比较新的发行版(内核 >= 3.6)可以开启 AF\_PACKET ,安装并启动 irqbalance 来获得更好的抓包性能。

首先编辑文件 /etc/fastnetmon.conf,将 mirror 的值改为 on ,这将使用 pf\_ring 作为抓包引擎。

    # PF_RING traffic capture, enough fast but wire speed version need paid license
    mirror = on

同时,可以顺便把报警阈值调小一点,方便后面测试攻击。

    # Limits for Dos/DDoS attacks threshold_pps = 200
    threshold_mbps = 10
    threshold_flows = 350

编辑 /etc/networks\_list 以 CIDR 格式添加需要监控的网段。
保存启动并保持在后台运行,同时可以添加到 /etc/rc.d/rc.local 开机启动。

    /opt/fastnetmon/fastnetmon --daemonize

查看日志

    tail -f /var/log/fastnetmon.log
  • 模拟 DDoS 攻击测试 FastNetMon

接下来我们测试 fastnetmon 是否能正确识别 DDoS 攻击。
首先我们配置一下 FastNetMon 的通知脚本

    wget https://raw.githubusercontent.com/pavel-odintsov/fastnetmon/master/src/notify_about_attack.sh -O/usr/local/bin/notify_about_attack.sh
    chmod 755 /usr/local/bin/notify_about_attack.sh

编辑这个脚本,找到 ban 的条件语句,由于只是进行测试,我仅仅输出一条消息到 /var/log/ban.log 日志中。

    if [ "$4" = "ban" ]; then
        echo "FastNetMon Guard: IP $1 blocked because $2 attack with power $3 pps" >> /var/log/ban.log
        exit 0
    fi

这样通知脚本就配置好了。

我使用 iperf 工具来模拟 DDoS 攻击,这个工具一般用于测试网络带宽,当然也可以通过大量发包模拟一次 DDoS 攻击。
在 CentOS 上可以通过 yum 直接安装 iperf:yum install iperf
然后通过 iperf -su 命令启动 iperf 的服务器端。
这里 -u 参数指明侦听 udp 端口。
我将我的 mbp 作为攻击的发器端,同样安装 iperf : brew install iperf
在客户端上向服务器发起探测:iperf -u -c 10.1.2.137 -b 100M -P 5
这时,在服务器上执行 FastNetMon 的客户端命令 /opt/fastnetmon/fastnetmon\_clinet 进行查看,可以看到出现如下信息。

    FastNetMon v1.0 FastVPS Eesti OU (c) VPS and dedicated: http://FastVPS.host
    IPs ordered by: packets
    Incoming traffic         42594 pps    491 mbps      0 flows
    10.1.2.137               35552 pps    410 mbps      0 flows  *banned*
    
    Outgoing traffic             1 pps    0 mbps      0 flows
    10.1.2.137                   1 pps    0 mbps      0 flows  *banned*
    
    Internal traffic             0 pps    0 mbps
    
    Other traffic                0 pps    0 mbps
    
    Screen updated in:              0 sec 191 microseconds
    Traffic calculated in:          0 sec 7 microseconds
    Total amount of not processed packets: 0
    Packets received:    404792
    Packets dropped:        0
    Packets dropped:        0.0 %
    
    Ban list:
    10.1.2.137/35552 pps incoming at 04_06_16_00:40:13

因为之前我设置了攻击阈值为 200 pps,10 mb,目前的这个负载量已经远远超过我设定的阈值,被认为遭到了攻击。可以看到,目前 10.1.2.137 这个 IP 已经被拉进 Ban list 之中了。

现在我们查看 FastNetMon 是否触发了通知,查看 /var/log/ban.log 这个日志,可以看到通知的消息。

    FastNetMon Guard: IP 10.1.2.137 blocked because incoming attack with power 293 pps

FastNetMon 确实触发了通知的操作。

安装 InfluxDB

    wget https://dl.influxdata.com/influxdb/releases/influxdb-1.7.6.x86_64.rpm
    sudo yum localinstall influxdb-1.7.6.x86_64.rpm

编辑 InfluxDB 的配置文件 /etc/influxdb/influxdb.conf 中的 graphite 选项,按照如下配置:

    [[graphite]]
      enabled = true
      bind-address = "127.0.0.1:2003"
      database = "dc1"
      protocol = "tcp"
      consistency-level = "one"
      name-separator = "."
    
      # batch-size / batch-timeout requires InfluxDB >= 0.9.3
      batch-size = 5000 # will flush if this many points get buffered
      batch-timeout = "1s" # will flush at least this often even if we haven't hit buffer limit
    
      templates = [
        "fastnetmon.hosts.* app.measurement.cidr.direction.function.resource",
        "fastnetmon.networks.* app.measurement.cidr.direction.resource",
        "fastnetmon.total.* app.measurement.direction.resource"
      ]
    

现在就可以启动 InfluxDB 了。

    systemctl start influxdb 
    

同样,需要在 FastNetMon 的配置文件 /etc/fastnetmon.conf 里做一些配置。

    graphite = on
    graphite_host = 127.0.0.1
    graphite_port = 2003
    graphite_prefix = fastnetmon

保存好后重启 FastNetMon。

安装 Grafana

    wget https://dl.grafana.com/oss/release/grafana-6.1.6-1.x86_64.rpm 
    sudo yum localinstall grafana-6.1.6-1.x86_64.rpm

启动。

    service grafana-server start

InfluxDB 作为数据源添加,并通过 Grafana 官方给出示例模板添加图表。
模板链接:https://grafana.com/dashboards/7378
如果正确配置,这时已经可以看到数据了。

附 Fastnetmon 配置文件:

    ###
    ### Main configuration params
    ###
    
    ### Logging configuration
    
    # enable this option if you want to send logs to local syslog facility
    logging:local_syslog_logging = off
    
    # enable this option if you want to send logs to a remote syslog server via UDP
    logging:remote_syslog_logging = off
    
    # specify a custom server and port for remote logging
    logging:remote_syslog_server = 10.10.10.10
    logging:remote_syslog_port = 514
    
    # Enable/Disable any actions in case of attack
    enable_ban = on
    
    # disable processing for certain direction of traffic
    process_incoming_traffic = on
    process_outgoing_traffic = on
    
    # How many packets will be collected from attack traffic
    ban_details_records_count = 500
    
    # How long (in seconds) we should keep an IP in blocked state
    # If you set 0 here it completely disables unban capability
    ban_time = 1900
    
    # Check if the attack is still active, before triggering an unban callback with this option
    # If the attack is still active, check each run of the unban watchdog
    unban_only_if_attack_finished = on
    
    # enable per subnet speed meters
    # For each subnet, list track speed in bps and pps for both directions
    enable_subnet_counters = on
    
    # list of all your networks in CIDR format
    networks_list_path = /etc/networks_list
    
    # list networks in CIDR format which will be not monitored for attacks
    white_list_path = /etc/networks_whitelist
    
    # redraw period for client's screen
    check_period = 1
    
    # Connection tracking is very useful for attack detection because it provides huge amounts of information,
    # but it's very CPU intensive and not recommended in big networks
    enable_connection_tracking = off
    
    # Different approaches to attack detection
    ban_for_pps = on
    ban_for_bandwidth = on
    ban_for_flows = off
    
    # Limits for Dos/DDoS attacks
    threshold_pps = 20000
    threshold_mbps = 1000
    threshold_flows = 3500
    
    # Per protocol attack thresholds
    # We don't implement per protocol flow limits, sorry :(
    # These limits should be smaller than global pps/mbps limits
    
    threshold_tcp_mbps = 100000
    threshold_udp_mbps = 100000
    threshold_icmp_mbps = 100000
    
    threshold_tcp_pps = 100000
    threshold_udp_pps = 100000
    threshold_icmp_pps = 100000
    
    ban_for_tcp_bandwidth = off
    ban_for_udp_bandwidth = off
    ban_for_icmp_bandwidth = off
    
    ban_for_tcp_pps = off
    ban_for_udp_pps = off
    ban_for_icmp_pps = off
    
    ###
    ### Traffic capture methods
    ###
    
    # PF_RING traffic capture, fast enough but the wirespeed version needs a paid license
    mirror = off
    
    # Port mirroring sample rate
    pfring_sampling_ratio = 1
    
    # Netmap traffic capture (very fast but needs patched drivers)
    mirror_netmap = off
    
    # SnabbSwitch traffic capture
    mirror_snabbswitch = off
    
    # AF_PACKET capture engine
    # Please use it only with modern Linux kernels (3.6 and more)
    # And please install birq for irq ditribution over cores
    mirror_afpacket = off
    
    # use PCI-e addresses here instead of OS device names. You can find them in "lspci" output
    interfaces = eth0
    
    # Port mirroring sampling ratio
    netmap_sampling_ratio = 1
    
    # This option should be enabled if you are using Juniper with mirroring of the first X bytes of packet: maximum-packet-length 110;
    netmap_read_packet_length_from_ip_header = off
    
    # Pcap mode, very slow and thus not suitable for production
    pcap = off
    # Netflow capture method with v5, v9 and IPFIX support
    netflow = on
    # sFLOW capture suitable for switches
    sflow = off
    
    # PF_RING configuration
    # If you have a license for PF_RING ZC, enable this mode and it might achieve wire speed for 10GE
    enable_pf_ring_zc_mode = off
    
    # Configuration for netmap, mirror, pcap modes
    # For pcap and PF_RING we could specify "any"
    # For netmap and PF_RING we could specify multiple interfaces = eth0
    interfaces = eth0
    
    # We use average values for traffic speed to certain IP and we calculate average over this time slice
    average_calculation_time = 5
    
    # We use average values for traffic speed for subnet and we calculate average over this time slice
    average_calculation_time_for_subnets = 20
    
    # Netflow configuration
    
    # it's possible to specify multiple ports here, using commas as delimiter
    netflow_port = 1234
    netflow_host = 0.0.0.0
    
    # To bind to all interfaces = eth0
    # To bind to all interfaces = eth0
    # To bind to localhost for a specific protocol:      ::1 or 127.0.0.1
    
    # Netflow v9 and IPFIX agents use different and very complex approaches for notifying about sample ratio
    # Here you could specify a sampling ratio for all this agents
    # For NetFLOW v5 we extract sampling ratio from packets directely and this option not used
    netflow_sampling_ratio = 1
    
    # In some cases with NetFlow we could get huge bursts related to aggregated data nature
    # We could try to get smoother data with this option, i.e. we will divide counters on collection interval time
    netflow_divide_counters_on_interval_length = off
    
    # Process each netflow packet with LUA
    # This option is not default and you need build it additionally
    # netflow_lua_hooks_path = /usr/src/fastnetmon/src/netflow_hooks.lua
    
    # sFLOW configuration
    
    # It's possible to specify multiple ports here, using commas as delimiter
    sflow_port = 6343
    # sflow_port = 6343,6344
    sflow_host = 0.0.0.0
    
    # process each sFLOW packet with LUA
    # This option is not default and you need build it additionally
    # sflow_lua_hooks_path = /usr/src/fastnetmon/src/sflow_hooks.lua
    
    # sFlow processing QinQ
    sflow_qinq_process = off
    
    # sFlow ethertype of outer tag in QinQ
    sflow_qinq_ethertype = 0x8100
    
    ###
    ### Actions when attack detected
    ###
    
    # This script executed for ban, unban and attack detail collection
    notify_script_path = /usr/local/bin/notify_about_attack.sh
    
    # pass attack details to notify_script via stdin
    # Pass details only in case of "ban" call
    # No details will be passed for "unban" call
    notify_script_pass_details = on
    
    # collect a full dump of the attack with full payload in pcap compatible format
    collect_attack_pcap_dumps = off
    
    # Execute Deep Packet Inspection on captured PCAP packets
    process_pcap_attack_dumps_with_dpi = off
    
    # Save attack details to Redis
    redis_enabled = off
    
    # Redis configuration
    redis_port = 6379
    redis_host = 127.0.0.1
    
    # specify a custom prefix here
    redis_prefix = mydc1
    
    # We could store attack information to MongoDB
    mongodb_enabled = off
    mongodb_host = localhost
    mongodb_port = 27017
    mongodb_database_name = fastnetmon
    
    # If you are using PF_RING non ZC version you could block traffic on host with hardware filters
    # Please be aware! We can not remove blocks with this action plugin
    pfring_hardware_filters_enabled = off
    
    # announce blocked IPs with BGP protocol with ExaBGP
    exabgp = off
    exabgp_command_pipe = /var/run/exabgp.cmd
    exabgp_community = 65001:666
    
    # specify multiple communities with this syntax:
    # exabgp_community = [65001:666 65001:777]
    
    # specify different communities for host and subnet announces
    # exabgp_community_subnet = 65001:667
    # exabgp_community_host = 65001:668
    
    exabgp_next_hop = 10.0.3.114
    
    # In complex cases you could have both options enabled and announce host and subnet simultaneously
    
    # Announce /32 host itself with BGP
    exabgp_announce_host = on
    
    # Announce origin subnet of IP address instead IP itself
    exabgp_announce_whole_subnet = off
    
    # Announce Flow Spec rules when we could detect certain attack type
    # Please we aware! Flow Spec announce triggered when we collect some details about attack,
    # i.e. when we call attack_details script
    # Please disable exabgp_announce_host and exabgp_announce_whole_subnet if you want to use this feature
    # Please use ExaBGP v4 only (Git version), for more details: https://github.com/pavel-odintsov/fastnetmon/blob/master/docs/BGP_FLOW_SPEC.md
    exabgp_flow_spec_announces = off
    
    # GoBGP intergation
    gobgp = off
    gobgp_next_hop = 0.0.0.0
    gobgp_announce_host = on
    gobgp_announce_whole_subnet = off
    
    # Graphite monitoring
    # InfluxDB is also supported, please check our reference:
    # https://github.com/pavel-odintsov/fastnetmon/blob/master/docs/INFLUXDB_INTEGRATION.md
    graphite = on
    # Please use only IP because domain names are not allowed here
    graphite_host = 127.0.0.1
    graphite_port = 2003
    
    # Default namespace for Graphite data
    graphite_prefix = fastnetmon
    
    # Add local IP addresses and aliases to monitoring list
    # Works only for Linux
    monitor_local_ip_addresses = on
    
    # Create group of hosts with non-standard thresholds
    # You should create this group before (in configuration file) specifying any limits
    hostgroup = my_hosts:10.10.10.221/32,10.10.10.222/32
    
    # Configure this group
    my_hosts_enable_ban = off
    
    my_hosts_ban_for_pps = off
    my_hosts_ban_for_bandwidth = off
    my_hosts_ban_for_flows = off
    
    my_hosts_threshold_pps = 20000
    my_hosts_threshold_mbps = 1000
    my_hosts_threshold_flows = 3500
    
    # Path to pid file for checking "if another copy of tool is running", it's useful when you run multiple instances of tool
    pid_path = /var/run/fastnetmon.pid
    
    # Path to file where we store information for fastnetmon_client
    cli_stats_file_path = /tmp/fastnetmon.dat
    
    # Enable gRPC api (required for fastnetmon_api_client tool)
    enable_api = off
    
    ###
    ### Client configuration
    ###
    
    # Field used for sorting in client, valid values are: packets, bytes or flows
    sort_parameter = packets
    # How much IPs will be listed for incoming and outgoing channel eaters
    max_ips_in_list = 7

参考文章:
http://echohn.github.io/2016/06/03/use-fastnetmon-and-grafana-to-build-a-graphical-ddos-early-warning-system/
https://blog.csdn.net/weixin\_41004350/article/details/78492397
http://ju.outofmemory.cn/entry/316687

Last modification:September 6, 2019
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