snmpa_mpd - Message Processing and Dispatch module for the SNMP agent
Please see following description for synopsis
snmpa_mpd(3) Erlang Module Definition snmpa_mpd(3)
NAME
snmpa_mpd - Message Processing and Dispatch module for the SNMP agent
DESCRIPTION
The module snmpa_mpd implements the version independent Message Pro-
cessing and Dispatch functionality in SNMP for the agent. It is sup-
posed to be used from a Network Interface process (Definition of Agent
Net if).
DATA TYPES
See the data types in snmpa_conf.
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_packet(Packet, From, State, NoteStore, Log) -> {ok, Vsn, Pdu,
PduMS, ACMData} | {discarded, Reason} | {discovery, DiscoPacket}
process_packet(Packet, From, LocalEngineID, State, NoteStore, Log) ->
{ok, Vsn, Pdu, PduMS, ACMData} | {discarded, Reason} | {discovery, Dis-
coPacket}
Types:
Packet = binary()
From = {TDomain, TAddr}
TDomain = transportDomainUdpIpv4 | transportDomainUdpIpv6
TAddr = {IpAddr, IpPort}
LocalEngineID = string()
IpAddr = inet:ip_address()
IpPort = inet:port_number()
State = mpd_state()
NoteStore = pid()
Log = snmp_log()
Vsn = 'version-1' | 'version-2' | 'version-3'
Pdu = #pdu
PduMs = integer()
ACMData = acm_data()
Reason = term()
DiscoPacket = binary()
Processes an incoming packet. Performs authentication and
decryption as necessary. The return values should be passed to
the agent.
Note:
Note that the use of the LocalEngineID argument is only intended
for special cases, if the agent is to "emulate" multiple
EngineIDs! By default, the agent uses the value of SnmpEngineID
(see SNMP-FRAMEWORK-MIB).
generate_response_msg(Vsn, RePdu, Type, ACMData, Log) -> {ok, Packet} |
{discarded, Reason}
generate_response_msg(Vsn, RePdu, Type, ACMData, LocalEngineID, Log) ->
{ok, Packet} | {discarded, Reason}
Types:
Vsn = 'version-1' | 'version-2' | 'version-3'
RePdu = #pdu
Type = atom()
ACMData = acm_data()
LocalEngineID = string()
Packet = binary()
Generates a possibly encrypted response packet to be sent to the
network. Type is the #pdu.type of the original request.
Note:
Note that the use of the LocalEngineID argument is only intended
for special cases, if the agent is to "emulate" multiple
EngineIDs! By default, the agent uses the value of SnmpEngineID
(see SNMP-FRAMEWORK-MIB).
generate_msg(Vsn, NoteStore, Pdu, MsgData, To) -> {ok, PacketsAndAd-
dresses} | {discarded, Reason}
generate_msg(Vsn, NoteStore, Pdu, MsgData, LocalEngineID, To) -> {ok,
PacketsAndAddresses} | {discarded, Reason}
Types:
Vsn = 'version-1' | 'version-2' | 'version-3'
NoteStore = pid()
Pdu = #pdu
MsgData = msg_data()
LocalEngineID = string()
To = [dest_addrs()]
PacketsAndAddresses = [{TDomain, TAddress, Packet}]
TDomain = snmpUDPDomain
TAddress = {Ip, Udp}
Ip = {integer(), integer(), integer(), integer()}
Udp = integer()
Packet = binary()
Generates a possibly encrypted request packet to be sent to the
network.
MsgData is the message specific data used in the SNMP message.
This value is received in a send_pdu or send_pdu_req message
from the agent. In SNMPv1 and SNMPv2c, this message data is the
community string. In SNMPv3, it is the context information.
To is a list of destination addresses and their corresponding
security parameters. This value is received in the same message
from the agent and then transformed trough process_taddrs before
passed to this function.
Note:
Note that the use of the LocalEngineID argument is only intended
for special cases, if the agent is to "emulate" multiple
EngineIDs! By default, the agent uses the value of SnmpEngineID
(see SNMP-FRAMEWORK-MIB).
process_taddrs(TDests) -> Dests
Types:
TDests = [TDest]
TDest = {{TDomain, TAddr}, SecData} | {TDomain, TAddr}
TDomain = term() % Not at tuple
TAddr = term()
SecData = term()
Dests = [Dest]
Dest = {{Domain, Addr}, SecData} | {Domain, Addr}
Domain = transportDomain()
Addr = transportAddress() % Depends on Domain
Transforms addresses from internal MIB format to one more useful
to Agent Net if.
See also generate_msg.
discarded_pdu(Variable) -> void()
Types:
Variable = atom()
Increments the variable associated with a discarded pdu. This
function can be used when the net_if process receives a dis-
carded_pdu message from the agent.
Ericsson AB snmp 5.11 snmpa_mpd(3)