Network.Protocol.Snmp.AgentX

About

Library for write extensible SNMP agents.

data MIB

MIB describe objects and object-types in internal tree with data.

Instances

Show MIB

data Value :: *

Snmp data types

Constructors

OI OID

Zero

Integer Int32

String ByteString

IpAddress Word8 Word8 Word8 Word8

Counter32 Word32

Gaude32 Word32

TimeTicks Word32

Opaque ByteString

Counter64 Word64

ZeroDotZero

NoSuchInstance

NoSuchObject

EndOfMibView

Instances

Eq Value

Show Value

ASN1Object Value

data PVal

Wrapper for value

Constructors

Read

Fields

readAIO :: IO Value

ReadWrite

Fields

readAIO :: IO Value

commitSetAIO :: Value -> IO CommitError

testSetAIO :: Value -> IO TestError

undoSetAIO :: Value -> IO UndoError

Instances

Show PVal

rwValue :: IO Value -> (Value -> IO CommitError) -> (Value -> IO TestError) -> (Value -> IO UndoError) -> PVal

PVal constructor for read write value

rsValue :: Value -> PVal

PVal constructor for read only value

rdValue :: IO Value -> PVal

PVal constructor for read only IO Value

newtype Update

Update, for rebuild oid tree in runtime

Constructors

Update

Fields

unUpdate :: forall m. (Monad m, MonadIO m, Functor m) => m [MIB]

Instances

Show Update

mkObject

Arguments

:: Integer

OID number for this object

-> Parent

parent name for this object

-> Name

name for this object

-> Maybe Update

Just Update if you need dynamic module

-> MIB

created MIB

Constructor for MIB, create Object in mib tree

mkObjectType

Arguments

:: Integer

OID number for this object

-> Parent

parent

-> Name

name

-> Maybe Context

context

-> PVal

value

-> MIB

created MIB

Constructor for MIB, create Object-Type in mib tree

data CommitError

result for commitSetAIO (rfc 2741, section 7.2.4.2)

Constructors

NoCommitError

CommitFailed

Instances

Eq CommitError

Show CommitError

data TestError

result for testSetAIO (rfc 2741, section 7.2.4.1)

Constructors

NoTestError

TooBig

NoSuchName

BadValue

ReadOnly

GenError

NoAccess

WrongType

WrongLength

WrongEncoding

WrongValue

NoCreation

InconsistentValue

ResourceUnavailable

NotWritable

InconsistentName

Instances

Eq TestError

Show TestError

data UndoError

result for undoSetAIO (rfc 2741, section 7.2.4.3)

Constructors

NoUndoError

UndoFailed

Instances

Eq UndoError

Show UndoError

data Context

rfc 2571 section 3.3.1, rfc 2741 section 6.1.1 Context

Instances

Eq Context

Ord Context

Show Context

IsString Context

agent

Arguments

:: FilePath

path to socket

-> OID

base oid

-> Maybe Client

client

-> [MIB]

MIBs

-> IO ()

start agent

runAgent :: OID -> [MIB] -> Maybe Client -> Socket -> IO ()

start agent with socket exit when catch sigQUIT, sigTERM, keyboardSignal show MIB tree when catch sigUSR1

data Client

if you need client

Instances

Default Client

by default just ping every 5s.

Usage

Imports

module Main where

import Network.Protocol.Snmp.AgentX 
import qualified Data.ByteString as BS
import Data.ByteString (ByteString)
import Data.Fixed (div')
import Data.Time.Clock.POSIX (getPOSIXTime)
import Control.Applicative ((<$>))
import Control.Monad.State
import Data.IORef

Desribe values for monitoring

str :: ByteString -> PVal
str x = rsValue (String x)

now :: PVal
now = rdValue $  TimeTicks . flip div' 1 <$> liftIO getPOSIXTime

rws :: IORef Value -> PVal
rws io = rwValue readV commit test undo
  where
    test (String x) 
      | BS.length x < 10 = return NoTestError
      | otherwise = return TooBig
    test _ = return WrongType
    commit v = do
        writeIORef io v
        return NoCommitError
    undo _ = return NoUndoError
    readV = readIORef io

rwi :: IORef Value -> PVal
rwi io = rwValue readV commit test undo
  where
    test (Integer x) 
      | x < 5 = return NoTestError
      | otherwise = return TooBig
    test _ = return WrongType
    commit v = do
        writeIORef io v
        return NoCommitError
    undo _ = return NoUndoError
    readV = readIORef io

Build dynamic tree

dynTree :: IORef Value -> Update
dynTree i = Update $ do
    Integer count <- liftIO $ readIORef i
    return $ concatMap fun [0 .. count]
    where
    fun x = [ mkObject (fromIntegral x) "trees" ("tree" ++ show x) Nothing
            , mkObjectType 0 ("tree" ++ show x) "abr" Nothing (str "abr")
            , mkObjectType 1 ("tree" ++ show x) "abrvalg" Nothing (str "abrvalg")
            ]

Describe context

ver :: Maybe Context
ver = Just "version"

Construct full tree

simpleTree :: IORef Value -> IORef Value -> [MIB]
simpleTree m i = 
      [ mkObject 0 "Fixmon" "about" Nothing
      , mkObjectType 0 "about" "name" Nothing $ rsValue (String "Fixmon agent")
      , mkObjectType 1 "about" "version" Nothing $ rsValue (String "0.0.1")
      , mkObjectType 1 "about" "version" ver $ rsValue (String "Alpha")
      , mkObjectType 2 "about" "comment" Nothing (rws m) 
      , mkObject 1 "Fixmon" "dyn" Nothing
      , mkObjectType 0 "dyn" "counter" Nothing (rwi i)
      , mkObject 1 "dyn" "trees" (Just $ dynTree i)
      ]

tree :: IO [MIB]
tree = do
    m <- newIORef (String "init")
    i <- newIORef (Integer 0)
    return $ simpleTree m i

Start subagent

main :: IO ()
main = agent "/var/agentx/master" [1,3,6,1,4,1,44729] Nothing =<< tree

Examples

SNMP server config
> cat /etc/snmp/snmpd.conf
> rwuser sha
> createUser sha SHA "password" DESi
> master agentx
> agentXPerms 777 775

SNMP client config
> cat /etc/snmp/snmp.conf
> defVersion 3
> defSecurityName sha
> defSecurityLevel authPriv
> defPassphrase password
> defAuthType SHA
> defPrivType DES
> defContext ""

Build example
> cabal install -f example
Start SNMP server
> sudo snmpd
Start SNMP agent
> .cabal-sandbox/bin/agentx_example

Get MIB tree
 > snmpwalk -r 1 -On localhost 1.3.6.1.4.1.44729
 > .1.3.6.1.4.1.44729.0.0 = STRING: "Fixmon agent"
 > .1.3.6.1.4.1.44729.0.1 = STRING: "0.0.1"
 > .1.3.6.1.4.1.44729.0.2 = STRING: "init"
 > .1.3.6.1.4.1.44729.1.0 = INTEGER: 0
 > .1.3.6.1.4.1.44729.1.1.0.0 = STRING: "abr"
 > .1.3.6.1.4.1.44729.1.1.0.1 = STRING: "abrvalg"
 
Change MIB tree 
 >  snmpset -r 1  -On localhost .1.3.6.1.4.1.44729.1.0 i 2
 > .1.3.6.1.4.1.44729.1.0 = INTEGER: 2
 >  snmpwalk -r 1 -On localhost 1.3.6.1.4.1.44729
 > .1.3.6.1.4.1.44729.0.0 = STRING: "Fixmon agent"
 > .1.3.6.1.4.1.44729.0.1 = STRING: "0.0.1"
 > .1.3.6.1.4.1.44729.0.2 = STRING: "init"
 > .1.3.6.1.4.1.44729.1.0 = INTEGER: 2
 > .1.3.6.1.4.1.44729.1.1.0.0 = STRING: "abr"
 > .1.3.6.1.4.1.44729.1.1.0.1 = STRING: "abrvalg"
 > .1.3.6.1.4.1.44729.1.1.1.0 = STRING: "abr"
 > .1.3.6.1.4.1.44729.1.1.1.1 = STRING: "abrvalg"
 > .1.3.6.1.4.1.44729.1.1.2.0 = STRING: "abr"
 > .1.3.6.1.4.1.44729.1.1.2.1 = STRING: "abrvalg"