func (self *internal_pinger) serve() {
defer self.wait.Done()
reply := make([]byte, 2048)
var buffer C.asn_buf_t
var pdu C.snmp_pdu_t
for 1 == atomic.LoadInt32(&self.is_running) {
l, ra, err := self.conn.ReadFrom(reply)
if err != nil {
if strings.Contains(err.Error(), "No service is operating") { //Port Unreachable
continue
}
if strings.Contains(err.Error(), "forcibly closed by the remote host") { //Port Unreachable
continue
}
self.ch <- &PingResult{Error: fmt.Errorf("ReadFrom failed: %v, %v", ra, err)}
continue
}
C.set_asn_u_ptr(&buffer.asn_u, (*C.char)(unsafe.Pointer(&reply[0])))
buffer.asn_len = C.size_t(l)
err = DecodePDUHeader(&buffer, &pdu)
if nil != err {
self.ch <- &PingResult{Error: fmt.Errorf("Parse Data failed: %s %v", ra.String(), err)}
continue
}
ver := SNMP_Verr
id := 0
//community := ""
switch pdu.version {
case uint32(SNMP_V3):
ver = SNMP_V3
id = int(pdu.identifier)
case uint32(SNMP_V2C):
ver = SNMP_V2C
err = DecodePDUBody(&buffer, &pdu)
if nil == err {
id = int(pdu.request_id)
}
//community = C.GoString(pdu.community)
case uint32(SNMP_V1):
ver = SNMP_V1
err = DecodePDUBody(&buffer, &pdu)
if nil == err {
id = int(pdu.request_id)
}
//community = C.GoString(pdu.community)
}
// if 0 == len(community) {
// community = self.community
// }
self.ch <- &PingResult{Id: id, Addr: ra, Version: ver, Community: self.community, SecurityParams: self.securityParams, Timestamp: time.Now()}
C.snmp_pdu_free(&pdu)
}
}
func encodeNativePdu(bs []byte, pdu *C.snmp_pdu_t) ([]byte, SnmpError) {
if pdu.engine.max_msg_size == 0 {
pdu.engine.max_msg_size = C.int32_t(*maxPDUSize)
}
var buffer C.asn_buf_t
C.set_asn_u_ptr(&buffer.asn_u, (*C.char)(unsafe.Pointer(&bs[0])))
buffer.asn_len = C.size_t(len(bs))
ret_code := C.snmp_pdu_encode(pdu, &buffer)
if 0 != ret_code {
err := Error(SnmpResult(ret_code), C.GoString(C.snmp_pdu_get_error(pdu, ret_code)))
return nil, err
}
length := C.get_buffer_length(&buffer, (*C.u_char)(unsafe.Pointer(&bs[0])))
return bs[0:length], nil
}
func DecodePDU(send_bytes []byte, priv_type PrivType, priv_key []byte, is_dump bool) (PDU, SnmpError) {
var buffer C.asn_buf_t
var pdu C.snmp_pdu_t
C.set_asn_u_ptr(&buffer.asn_u, (*C.char)(unsafe.Pointer(&send_bytes[0])))
buffer.asn_len = C.size_t(len(send_bytes))
err := DecodePDUHeader(&buffer, &pdu)
if nil != err {
return nil, err
}
defer C.snmp_pdu_free(&pdu)
err = FillUser(&pdu, SNMP_AUTH_NOAUTH, nil, priv_type, priv_key)
if nil != err {
return nil, err
}
err = DecodePDUBody(&buffer, &pdu)
if nil != err {
return nil, err
}
if is_dump {
C.snmp_pdu_dump(&pdu)
}
var ok bool = false
if uint32(SNMP_V3) == pdu.version {
var v3 V3PDU
ok, err = v3.decodePDU(&pdu)
if ok {
return &v3, err
}
return nil, err
}
var v2 V2CPDU
ok, err = v2.decodePDU(&pdu)
if ok {
return &v2, err
}
return nil, err
}
func (client *UdpClient) handleRecv(recv_bytes []byte) {
defer func() {
if e := recover(); nil != e {
var buffer bytes.Buffer
buffer.WriteString(fmt.Sprintf("[panic]%v", e))
for i := 1; ; i += 1 {
_, file, line, ok := runtime.Caller(i)
if !ok {
break
}
buffer.WriteString(fmt.Sprintf(" %s:%d\r\n", file, line))
}
client.ERROR.Print(client.logCtx, buffer.String())
}
}()
var buffer C.asn_buf_t
var result PDU
var req *clientRequest
var ok bool
internal := newNativePdu()
C.snmp_pdu_init(internal)
defer releaseNativePdu(internal)
C.set_asn_u_ptr(&buffer.asn_u, (*C.char)(unsafe.Pointer(&recv_bytes[0])))
buffer.asn_len = C.size_t(len(recv_bytes))
err := DecodePDUHeader(&buffer, internal)
if nil != err {
client.ERROR.Print(client.logCtx, "decode head of pdu failed", err)
return
}
defer C.snmp_pdu_free(internal)
if uint32(SNMP_V3) == internal.version {
req, ok = client.pendings[int(internal.identifier)]
if !ok {
client.ERROR.Print(client.logCtx, "request with requestId was ", int(internal.identifier), " or ", int(internal.request_id), " is not exists.")
// for i, _ := range client.pendings {
// client.ERROR.Print(i)
// }
return
}
delete(client.pendings, int(internal.identifier))
v3old, ok := req.request.(*V3PDU)
if !ok {
err = Error(SNMP_CODE_FAILED, "receive pdu is a v3 pdu.")
goto complete
}
usm, ok := v3old.securityModel.(*USM)
if !ok {
err = Error(SNMP_CODE_FAILED, "receive pdu is not usm.")
goto complete
}
err = FillUser(internal, usm.auth_proto, usm.localization_auth_key,
usm.priv_proto, usm.localization_priv_key)
if nil != err {
client.ERROR.Print(client.logCtx, "fill user information failed,", err.Error())
goto complete
}
err, ok = DecodePDUBody2(&buffer, internal)
if nil != err {
client.ERROR.Print(client.logCtx, "decode body of pdu failed", err.Error())
goto complete
}
if ok {
client.ERROR.Print(client.logCtx, "ignored some error", hex.EncodeToString(recv_bytes))
}
if client.DEBUG.IsEnabled() {
C.snmp_pdu_dump(internal)
}
var v3 V3PDU
_, err = v3.decodePDU(internal)
result = &v3
} else {
err, ok = DecodePDUBody2(&buffer, internal)
if nil != err {
client.ERROR.Print(client.logCtx, "decode body of pdu failed", err.Error())
return
}
if ok {
client.ERROR.Print(client.logCtx, "ignored some error", hex.EncodeToString(recv_bytes))
}
req, ok = client.pendings[int(internal.request_id)]
if !ok {
client.ERROR.Print(client.logCtx, "request with requestId was", int(internal.request_id), "is not exists.")
return
}
delete(client.pendings, int(internal.request_id))
if client.DEBUG.IsEnabled() {
C.snmp_pdu_dump(internal)
}
v2 := &V2CPDU{}
_, err = v2.decodePDU(internal)
result = v2
}
complete:
req.reply(result, err)
}