NAME

       snmpm_mpd - Message Processing and Dispatch module for the SNMP manager

DESCRIPTION

       The  module  snmpm_mpd  implements the version independent Message Processing and Dispatch
       functionality in SNMP for the manager. It is supposed to be used from a Network  Interface
       process (Definition of Manager Net if).

       Legacy  API  function  process_msg/7 that has got separate IpAddr and PortNumber arguments
       still works as before for backwards compatibility reasons.

EXPORTS

       init(Vsns) -> mpd_state()

              Types:

                 Vsns = [Vsn]
                 Vsn = v1 | v2 | v3

              This function can be called from the net_if process at start-up. The  options  list
              defines which versions to use.

              It also initializes some SNMP counters.

       process_msg(Msg, Domain, Addr, State, NoteStore, Logger) -> {ok, Vsn, Pdu, PduMS, MsgData}
       | {discarded, Reason}

              Types:

                 Msg = binary()
                 Domain = transportDomainUdpIpv4 | transportDomainUdpIpv6
                 Addr = {inet:ip_address(), inet:port_number()}
                 State = mpd_state()
                 NoteStore = pid()
                 Logger = function()
                 Vsn = 'version-1' | 'version-2' | 'version-3'
                 Pdu = #pdu
                 PduMs = integer()
                 MsgData = term()

              Processes an incoming message. Performs authentication and decryption as necessary.
              The return values should be passed the manager server.

              NoteStore is the pid() of the note-store process.

              Logger is the function used for audit trail logging.

              In  the  case  when  the pdu type is report, MsgData is either ok or {error, ReqId,
              Reason}.

       generate_msg(Vsn, NoteStore, Pdu, MsgData, Logger) -> {ok, Packet} | {discarded, Reason}

              Types:

                 Vsn = 'version-1' | 'version-2' | 'version-3'
                 NoteStore = pid()
                 Pdu = #pdu
                 MsgData = term()
                 Logger = function()
                 Packet = binary()
                 Reason = term()

              Generates a possibly encrypted packet to be sent to the network.

              NoteStore is the pid() of the note-store process.

              MsgData is the message specific data used  in  the  SNMP  message.  In  SNMPv1  and
              SNMPv2c,  this  message  data is the community string. In SNMPv3, it is the context
              information.

              Logger is the function used for audit trail logging.

       generate_response_msg(Vsn, Pdu, MsgData, Logger) -> {ok, Packet} | {discarded, Reason}

              Types:

                 Vsn = 'version-1' | 'version-2' | 'version-3'
                 Pdu = #pdu
                 MsgData = term()
                 Logger = function()
                 Packet = binary()
                 Reason = term()

              Generates a possibly encrypted response packet to be sent to the network.

              MsgData is the message specific data used  in  the  SNMP  message.  This  value  is
              received from the process_msg function.