<?xml version="1.0" encoding="utf-8" ?>
<!DOCTYPE erlref SYSTEM "erlref.dtd">
<erlref>
<header>
<copyright>
<year>1996</year><year>2016</year>
<holder>Ericsson AB. All Rights Reserved.</holder>
</copyright>
<legalnotice>
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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</legalnotice>
<title>snmp_pdus</title>
<prepared></prepared>
<responsible></responsible>
<docno></docno>
<approved></approved>
<checked></checked>
<date></date>
<rev></rev>
<file>snmp_pdus.xml</file>
</header>
<module>snmp_pdus</module>
<modulesummary>Encode and Decode Functions for SNMP PDUs</modulesummary>
<description>
<p>RFC1157, RFC1905 and/or RFC2272 should be studied carefully
before using this module, <c>snmp_pdus</c>.
</p>
<p>The module <c>snmp_pdus</c> contains functions for encoding
and decoding of
SNMP protocol data units (PDUs). In short, this module converts a
list of bytes to Erlang record representations and vice versa.
The record definitions can be found in the file
<c>snmp/include/snmp_types.hrl</c>. If snmpv3 is used, the module
that includes <c>snmp_types.hrl</c> must define the constant
<c>SNMP_USE_V3</c> before the header file is included. Example:</p>
<pre>
-define(SNMP_USE_V3, true).
-include_lib("snmp/include/snmp_types.hrl"). </pre>
<p>Encoding and decoding must be done explicitly when writing your
own Net if process.
</p>
</description>
<funcs>
<func>
<name>dec_message([byte()]) -> Message</name>
<fsummary>Decode an SNMP Message</fsummary>
<type>
<v>Message = #message</v>
</type>
<desc>
<p>Decodes a list of bytes into an SNMP Message. Note, if there
is a v3 message, the <c>msgSecurityParameters</c> are not
decoded. They must be explicitly decoded by a call to a
security model specific decoding function,
e.g. <c>dec_usm_security_parameters/1</c>. Also note, if
the <c>scopedPDU</c> is encrypted, the OCTET STRING encoded
<c>encryptedPDU</c> will be present in the <c>data</c> field.</p>
</desc>
</func>
<func>
<name>dec_message_only([byte()]) -> Message</name>
<fsummary>Decode an SNMP Message, but not the data part</fsummary>
<type>
<v>Message = #message</v>
</type>
<desc>
<p>Decodes a list of bytes into an SNMP Message, but does not
decode the data part of the Message. That means, data is still
a list of bytes, normally an encoded <c>PDU</c> (v1 and V2) or an
encoded and possibly encrypted <c>scopedPDU</c> (v3).</p>
</desc>
</func>
<func>
<name>dec_pdu([byte()]) -> Pdu</name>
<fsummary>Decode an SNMP Pdu</fsummary>
<type>
<v>Pdu = #pdu</v>
</type>
<desc>
<p>Decodes a list of bytes into an SNMP Pdu.</p>
</desc>
</func>
<func>
<name>dec_scoped_pdu([byte()]) -> ScopedPdu</name>
<fsummary>Decode an SNMP ScopedPdu</fsummary>
<type>
<v>ScopedPdu = #scoped_pdu</v>
</type>
<desc>
<p>Decodes a list of bytes into an SNMP ScopedPdu.</p>
</desc>
</func>
<func>
<name>dec_scoped_pdu_data([byte()]) -> ScopedPduData</name>
<fsummary>Decode an SNMP ScopedPduData</fsummary>
<type>
<v>ScopedPduData = #scoped_pdu | EncryptedPDU</v>
<v>EncryptedPDU = [byte()]</v>
</type>
<desc>
<p>Decodes a list of bytes into either a scoped pdu record, or
- if the scoped pdu was encrypted - to a list of bytes.</p>
</desc>
</func>
<func>
<name>dec_usm_security_parameters([byte()]) -> UsmSecParams</name>
<fsummary>Decode SNMP UsmSecurityParameters</fsummary>
<type>
<v>UsmSecParams = #usmSecurityParameters</v>
</type>
<desc>
<p>Decodes a list of bytes into an SNMP UsmSecurityParameters</p>
</desc>
</func>
<func>
<name>enc_encrypted_scoped_pdu(EncryptedScopedPdu) -> [byte()]</name>
<fsummary>Encode an encrypted SNMP scopedPDU</fsummary>
<type>
<v>EncryptedScopedPdu = [byte()]</v>
</type>
<desc>
<p>Encodes an encrypted SNMP ScopedPdu into an OCTET STRING
that can be used as the <c>data</c> field in a
<c>message</c> record, that later can be encoded with a call
to <c>enc_message_only/1</c>.
</p>
<p>This function should be used whenever the <c>ScopedPDU</c>
is encrypted.</p>
</desc>
</func>
<func>
<name>enc_message(Message) -> [byte()]</name>
<fsummary>Encode an SNMP Message</fsummary>
<type>
<v>Message = #message</v>
</type>
<desc>
<p>Encodes a message record to a list of bytes.</p>
</desc>
</func>
<func>
<name>enc_message_only(Message) -> [byte()]</name>
<fsummary>Encode an SNMP Message, but not the data part</fsummary>
<type>
<v>Message = #message</v>
</type>
<desc>
<p><c>Message</c> is a record where the <c>data</c> field is
assumed to be encoded (a list of bytes). If there is a v1 or v2
message, the <c>data</c> field is an encoded <c>PDU</c>, and if
there is a v3 message, <c>data</c> is an encoded and possibly
encrypted <c>scopedPDU</c>.</p>
</desc>
</func>
<func>
<name>enc_pdu(Pd) -> [byte()]</name>
<fsummary>Encode an SNMP Pdu</fsummary>
<type>
<v>Pdu = #pdu</v>
</type>
<desc>
<p>Encodes an SNMP Pdu into a list of bytes.</p>
</desc>
</func>
<func>
<name>enc_scoped_pdu(ScopedPdu) -> [byte()]</name>
<fsummary>Encode an SNMP scopedPDU</fsummary>
<type>
<v>ScopedPdu = #scoped_pdu</v>
</type>
<desc>
<p>Encodes an SNMP ScopedPdu into a list of bytes, which can be
encrypted, and after encryption, encoded with
a call to <c>enc_encrypted_scoped_pdu/1</c>; or it can be
used as the <c>data</c> field in a <c>message</c> record, which
then can be encoded with <c>enc_message_only/1</c>.</p>
</desc>
</func>
<func>
<name>enc_usm_security_parameters(UsmSecParams) -> [byte()]</name>
<fsummary>Encode SNMP UsmSecurityParameters</fsummary>
<type>
<v>UsmSecParams = #usmSecurityParameters</v>
</type>
<desc>
<p>Encodes SNMP UsmSecurityParameters into a list of bytes.</p>
</desc>
</func>
</funcs>
</erlref>
