cmon

README

CMon

A Simple Connection Monitor Written in Go

Installation

To install CMon, simply run:

go get github.com/vaelen/cmon/cmds/cmon

Example Output

The output is well formatted MarkDown.

Thu, 06 Apr 2017 12:10:44 -0500

Active Connections

Interface	Source -> Destination	Count	State
lo	172.28.128.100:0 -> 172.28.128.100:0	1	Closed
lo	127.0.0.1:40066 -> 127.0.1.1:27000	29	Active
lo	127.0.1.1:27000 -> 127.0.0.1:40066	27	Active
enp0s3	0.0.0.0:68 -> 255.255.255.255:67	1	Closed
enp0s3	fe80::9892:755f:c064:a26:546 -> ff02::1:2:547	2	Closed
enp0s3	54.173.82.137:443 -> 192.168.1.135:50716	7	Closed
enp0s3	192.168.1.135:50716 -> 54.173.82.137:443	7	Active
enp0s8	:0 -> :0	3	Active

Inactive Connections

Source -> Destination	State
127.0.1.1:27000 -> 127.0.0.1:44778	Inactive
172.28.128.100:36948 -> 172.28.128.101:27000	New
172.28.128.100:36950 -> 172.28.128.101:27000	New
127.0.1.1:27000 -> 127.0.0.1:44730	Inactive
172.28.128.100:36948 -> 172.28.128.101:27000	New
172.28.128.100:36950 -> 172.28.128.101:27000	New
127.0.1.1:27000 -> 127.0.0.1:40134	Inactive
172.28.128.100:36948 -> 172.28.128.101:27000	New
172.28.128.100:36950 -> 172.28.128.101:27000	New
127.0.1.1:27000 -> 127.0.0.1:44724	Inactive
172.28.128.100:36948 -> 172.28.128.101:27000	New
172.28.128.100:36950 -> 172.28.128.101:27000	New
127.0.0.1:44778 -> 127.0.1.1:27000	Inactive
172.28.128.100:36948 -> 172.28.128.101:27000	New
172.28.128.100:36950 -> 172.28.128.101:27000	New
127.0.0.1:44728 -> 127.0.1.1:27000	Inactive
172.28.128.100:36950 -> 172.28.128.101:27000	New
172.28.128.100:36948 -> 172.28.128.101:27000	New
127.0.0.1:40086 -> 127.0.1.1:27000	Inactive
172.28.128.100:36950 -> 172.28.128.101:27000	New
172.28.128.100:36948 -> 172.28.128.101:27000	New
127.0.0.1:44726 -> 127.0.1.1:27000	Inactive
172.28.128.100:36948 -> 172.28.128.101:27000	New
172.28.128.100:36950 -> 172.28.128.101:27000	New
127.0.1.1:27000 -> 127.0.0.1:40086	Inactive
172.28.128.100:36948 -> 172.28.128.101:27000	New
172.28.128.100:36950 -> 172.28.128.101:27000	New
127.0.0.1:44730 -> 127.0.1.1:27000	Inactive
172.28.128.100:36948 -> 172.28.128.101:27000	New
172.28.128.100:36950 -> 172.28.128.101:27000	New
172.28.128.100:36950 -> 172.28.128.101:27000	New
172.28.128.100:36948 -> 172.28.128.101:27000	New
127.0.1.1:27000 -> 127.0.0.1:44726	Inactive
172.28.128.100:36950 -> 172.28.128.101:27000	New
172.28.128.100:36948 -> 172.28.128.101:27000	New
127.0.1.1:27000 -> 127.0.0.1:44728	Inactive
172.28.128.100:36948 -> 172.28.128.101:27000	New
172.28.128.100:36950 -> 172.28.128.101:27000	New
127.0.0.1:44724 -> 127.0.1.1:27000	Inactive
172.28.128.100:36948 -> 172.28.128.101:27000	New
172.28.128.100:36950 -> 172.28.128.101:27000	New
172.28.128.100:36948 -> 172.28.128.101:27000	New
172.28.128.100:36950 -> 172.28.128.101:27000	New
172.28.128.100:36950 -> 172.28.128.101:27000	New
172.28.128.100:36948 -> 172.28.128.101:27000	New
127.0.0.1:40134 -> 127.0.1.1:27000	Inactive
172.28.128.100:36948 -> 172.28.128.101:27000	New
172.28.128.100:36950 -> 172.28.128.101:27000	New
172.28.128.100:36950 -> 172.28.128.101:27000	New
172.28.128.100:36948 -> 172.28.128.101:27000	New

Documentation

Index

• Constants
• func AsUint16(val interface{}) uint16
• func Monitor(ifNames []string, filter string, printInterval time.Duration, verbose bool)
• type Event
  • func Connections(mode Mode) []Event
  • func (e *Event) String() string
• type Mode
  • func FindMode() Mode
• type PrinterConfig
• type SnifferConfig
• type State
• type Stats

Constants

const ChannelBufferSize int = 100

Functions

func AsUint16

func AsUint16(val interface{}) uint16

func Monitor

func Monitor(ifNames []string, filter string, printInterval time.Duration, verbose bool)

Types

type Event

type Event struct {
	SrcIP   net.IP
	SrcPort uint16
	DstIP   net.IP
	DstPort uint16
	State   State
}

func Connections

func Connections(mode Mode) []Event

func (*Event) String

func (e *Event) String() string

type Mode

type Mode int

const (
	SS Mode = iota
	NETSTAT
)

func FindMode

func FindMode() Mode

type PrinterConfig

type PrinterConfig struct {
	Logger        *log.Logger
	Sources       []SnifferConfig
	PrintInterval time.Duration
}

type SnifferConfig

type SnifferConfig struct {
	IfName   string
	Filter   string
	Request  chan bool
	Response chan *Stats
	Event    chan Event
	Verbose  bool
}

type State

type State int

const (
	ACTIVE State = iota
	ESTABLISHED
	OTHER
)

type Stats

type Stats struct {
	Counts map[string]uint64
}