func GetValue(oid asn1.ObjectIdentifier, community string, addr net.UDPAddr) (interface{}, error) {
conn, err := net.DialUDP("udp", nil, &addr)
if err != nil {
return nil, err
}
defer conn.Close()
r := PDU{
RequestId: 199,
ErrorStatus: 0,
ErrorIndex: 0,
VarBindList: []VarBind{
VarBind{
Name: oid,
Value: Null(),
},
},
}
data, err := asn1.Marshal(r)
if err != nil {
return nil, err
}
m := Message{
Version: 1,
Community: NewOctetString(community),
Data: Any(data),
}
data, err = asn1.Marshal(m)
if err != nil {
return nil, err
}
_, err = conn.Write(data)
if err != nil {
return nil, err
}
data = make([]byte, 1500)
read, err := conn.Read(data)
if err != nil {
return nil, err
}
pdu, err := decode(data[:read])
if err != nil {
return nil, err
}
switch response := pdu.(type) {
case *PDU:
return parseVarValue(response.VarBindList[0].Value)
}
return nil, nil
}
func TestSNMPGetNextRequest(t *testing.T) {
r := PDU{
RequestId: 199,
ErrorStatus: 0,
ErrorIndex: 0,
VarBindList: []VarBind{
VarBind{
Name: []int{1, 3, 6, 1, 2, 1, 1, 1, 0},
Value: Null(),
},
},
}
data, err := asn1.Marshal(r)
if err != nil {
t.Error(err)
}
m := Message{
Version: 1,
Community: NewOctetString("timer"),
Data: Any(data),
}
data, err = asn1.Marshal(m)
if err != nil {
t.Error(err)
}
addr := net.UDPAddr{net.IPv4(192, 168, 1, 254), 161}
conn, err := net.DialUDP("udp4", nil, &addr)
if err != nil {
t.Error(err)
}
defer conn.Close()
written, err := conn.Write(data)
if err != nil {
t.Error(err)
}
if written != len(data) {
t.Errorf("did not write the full data %d", written)
}
}
