Floodlight Static Flow Pusher API

什么是 Static Flow Pusher?

Static Flow Pusher 是一个 Floodlight 模块，使用的是REST API接口,允许用户在OpenFlow 网络中插入流表。

主动式和反应式流插入

OpenFlow 支持两种流表插入: 主动式和反应式。当数据包抵达OpenFlow交换机，而交换机没有该包对应的匹配流表时，反应时流表插入起作用。该数据包被送到控制器，由控制器进行评估，并向交换机添加相应的流表，从而把该数据包正确的转发出去。主动式插入则是在数据包到达之前就插入相应的流表，这就是两种方式的区别。

Static Flow Pusher 对于主动式流表插入很有用。Floodlight 默认会加载 Forwarding模块，该模块使用反应式流插入，如果你只想使用静态流，你可以在floodlight.properties配置文件中删除 Forwarding。

API 概要

URI
Description
Arguments
/wm/staticflowentrypusher/json静态流添加或删除操作HTTP POST data (add flow), HTTP DELETE (for deletion)/wm/staticflowentrypusher/list/<switch>/json列举交换机的静态流表switch: Valid Switch DPID (XX:XX:XX:XX:XX:XX:XX:XX) or "all"/wm/staticflowentrypusher/clear/<switch>/json清除交换机的静态流表switch: Valid Switch DPID (XX:XX:XX:XX:XX:XX:XX:XX) or "all"

添加静态流操作

静态流添加是通过REST API接口来进行的。例如，在交换机1上插入一条让数据包从端口1进端口2出的流表，则可以使用curl命令。第二个命令可以显示插入的流表。

curl -d '{"switch": "00:00:00:00:00:00:00:01", "name":"flow-mod-1", "priority":"32768", "ingress-port":"1","active":"true", "actions":"output=2"}' http://<controller_ip>:8080/wm/staticflowentrypusher/jsoncurl http://<controller_ip>:8080/wm/core/switch/1/flow/json;

删除静态流操作

通过包含流表名字的 HTTP DELETE命令来删除指定流表。

curl -X DELETE -d '{"name":"flow-mod-1"}' http://<controller_ip>:8080/wm/staticflowentrypusher/json

flow entry的可能属性

Key
Value
Notes
switch<switch ID>ID of the switch (data path) that this rule should be added to
xx:xx:xx:xx:xx:xx:xx:xxname<string>Name of the flow entry, this is the primary key, it MUST be uniqueactions<key>=<value>See table of actions below
Specify multiple actions using a comma-separated list
Specifying no actions will cause the packets to be droppedpriority<number>default is 32767
maximum value is 32767active<boolean> wildcards  ingress-port<number>switch port on which the packet is received
Can be hexadecimal (with leading 0x) or decimalsrc-mac<mac address>xx:xx:xx:xx:xx:xxdst-mac<mac address>xx:xx:xx:xx:xx:xxvlan-id<number>Can be hexadecimal (with leading 0x) or decimalvlan-priority<number>Can be hexadecimal (with leading 0x) or decimalether-type<number>Can be hexadecimal (with leading 0x) or decimaltos-bits<number>Can be hexadecimal (with leading 0x) or decimalprotocol<number>Can be hexadecimal (with leading 0x) or decimalsrc-ip<ip address>xx.xx.xx.xxdst-ip<ip address>xx.xx.xx.xxsrc-port<number>Can be hexadecimal (with leading 0x) or decimaldst-port<number>Can be hexadecimal (with leading 0x) or decimal

Possible actions within the "action" field:

Key
ValueNotesoutput<number>
all
controller
local
ingress-port
normal
floodno "drop" option
(instead, specify no action to drop packets)
enqueue<number>:<number>First number is port number, second is queue ID
Can be hexadecimal (with leading 0x) or decimalstrip-vlan  set-vlan-id<number>Can be hexadecimal (with leading 0x) or decimalset-vlan-priority<number>Can be hexadecimal (with leading 0x) or decimalset-src-mac<mac address>xx:xx:xx:xx:xx:xxset-dst-mac<mac address>xx:xx:xx:xx:xx:xxset-tos-bits<number> set-src-ip<ip address>xx.xx.xx.xxset-dst-ip<ip address>xx.xx.xx.xxset-src-port<number>Can be hexadecimal (with leading 0x) or decimalset-dst-port<number>Can be hexadecimal (with leading 0x) or decimal

静态流表插入的实际应用

我们可以使用Python脚本写流表操作，例如, 使用mininet产生一个简单的拓扑，并连接上控制器,默认的拓扑是一个交换机（s1）和两个主机（h2和h3）。

sudo mn --controller=remote --ip=<controller ip> --port=6633

下面的代码插入从h2到h3的流和h3到h2的流。

import httplibimport jsonclass StaticFlowPusher(object):    def __init__(self, server):        self.server = server    def get(self, data):        ret = self.rest_call({}, 'GET')        return json.loads(ret[2])    def set(self, data):        ret = self.rest_call(data, 'POST')        return ret[0] == 200    def remove(self, objtype, data):        ret = self.rest_call(data, 'DELETE')        return ret[0] == 200    def rest_call(self, data, action):        path = '/wm/staticflowentrypusher/json'        headers = {            'Content-type': 'application/json',            'Accept': 'application/json',            }        body = json.dumps(data)        conn = httplib.HTTPConnection(self.server, 8080)        conn.request(action, path, body, headers)        response = conn.getresponse()        ret = (response.status, response.reason, response.read())        print ret        conn.close()        return retpusher = StaticFlowPusher('<insert_controller_ip')flow1 = {    'switch':"00:00:00:00:00:00:00:01",    "name":"flow-mod-1",    "cookie":"0",    "priority":"32768",    "ingress-port":"1",    "active":"true",    "actions":"output=flood"    }flow2 ={    'switch':"00:00:00:00:00:00:00:01",    "name":"flow-mod-2",    "cookie":"0",    "priority":"32768",    "ingress-port":"2",    "active":"true",    "actions":"output=flood"    }pusher.set(flow1)pusher.set(flow2)

通过ping命令进行测试

 mininet> h2 ping h3