[prev in list] [next in list] [prev in thread] [next in thread] 

List:       net-snmp-coders
Subject:    Re: To understand the increase in size of buffer in agentx_parse() in net-snmp-5.8
From:       "Vijay, Anjali" <anjali.vijay () hp ! com>
Date:       2019-04-29 2:53:04
Message-ID: CS1PR8401MB1112BE4733E62C7DB1395029EF390 () CS1PR8401MB1112 ! NAMPRD84 ! PROD ! OUTLOOK ! COM
[Download RAW message or body]

Thanks Bart !!


Regards,

Anjali S. Vijay


________________________________
From: Bart Van Assche <bvanassche@acm.org>
Sent: Sunday, April 28, 2019 3:38 AM
To: Vijay, Anjali; net-snmp-coders@lists.sourceforge.net
Subject: Re: To understand the increase in size of buffer in agentx_parse()=
 in net-snmp-5.8

On 4/25/19 5:56 PM, Bart Van Assche wrote:
On 4/25/19 8:00 AM, Vijay, Anjali wrote:

I recently started working with net-snmp-5.8. I had a query over a change t=
hat was made to agentx_parse() in agent/mibgroup/agentx/protocol.c. I notic=
ed that the buffer of  SNMP_MAX_MSG_SIZE (1472) in net-snmp-5.7.3 has been =
replaced with the size 65536 in net-snmp-5.8.



u_char buffer[65536];



I didn=92t find any clarification in the ChangeLogs for this large increase=
 of size. Can this size be reduced? It would be of great help if anyone can=
 clear me out on this since my application has memory constraints.

Hi Anjali,

I will have a look and see whether it is possible to modify the AgentX code=
 without reducing performance and without dropping support for large AgentX=
 packets. BTW, the following commit increased the buffer size:

c09140c934eb ("CHANGES: snmpd: Increase maximum AgentX packet size to 64kB.=
")

Hi Anjali,

A candidate fix has been checked in on the v5.8 and master branches. Please=
 verify.

Bart.

[Attachment #3 (text/html)]

<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=Windows-1252">
<style type="text/css" style="display:none;"><!-- P {margin-top:0;margin-bottom:0;} \
--></style> </head>
<body dir="ltr">
<div id="divtagdefaultwrapper" style="font-size: 12pt; color: rgb(0, 0, 0); \
font-family: Calibri, Helvetica, sans-serif, &quot;EmojiFont&quot;, &quot;Apple Color \
Emoji&quot;, &quot;Segoe UI Emoji&quot;, NotoColorEmoji, &quot;Segoe UI Symbol&quot;, \
&quot;Android Emoji&quot;, EmojiSymbols;" dir="ltr"> <p \
style="margin-top:0;margin-bottom:0">Thanks Bart !!&nbsp;<br> </p>
<p style="margin-top:0;margin-bottom:0"><br>
</p>
<div id="Signature">
<p>Regards,</p>
<p>Anjali S. Vijay</p>
</div>
<br>
<br>
<div style="color: rgb(0, 0, 0);">
<hr style="display:inline-block;width:98%" tabindex="-1">
<div id="divRplyFwdMsg" dir="ltr"><font style="font-size:11pt" face="Calibri, \
sans-serif" color="#000000"><b>From:</b> Bart Van Assche \
&lt;bvanassche@acm.org&gt;<br> <b>Sent:</b> Sunday, April 28, 2019 3:38 AM<br>
<b>To:</b> Vijay, Anjali; net-snmp-coders@lists.sourceforge.net<br>
<b>Subject:</b> Re: To understand the increase in size of buffer in agentx_parse() in \
net-snmp-5.8</font> <div>&nbsp;</div>
</div>
<div style="background-color:#FFFFFF">
<div class="x_moz-cite-prefix">On 4/25/19 5:56 PM, Bart Van Assche wrote:<br>
</div>
<blockquote type="cite">
<div class="x_moz-cite-prefix">On 4/25/19 8:00 AM, Vijay, Anjali wrote:<br>
</div>
<blockquote type="cite">
<meta name="Generator" content="Microsoft Word 15 (filtered
          medium)">
<div class="x_WordSection1">
<p class="x_MsoNormal">I recently started working with net-snmp-5.8. I had a query \
over a change that was made to agentx_parse() in agent/mibgroup/agentx/protocol.c. I \
noticed that the buffer of &nbsp;SNMP_MAX_MSG_SIZE (1472) in net-snmp-5.7.3 has been \
replaced  with the size 65536 in net-snmp-5.8. </p>
<p class="x_MsoNormal">&nbsp;</p>
<p class="x_MsoNormal">u_char buffer[65536];</p>
<p class="x_MsoNormal">&nbsp;</p>
<p class="x_MsoNormal">I didn’t find any clarification in the ChangeLogs for this \
large increase of size. Can this size be reduced? It would be of great help if anyone \
can clear me out on this since my application has memory constraints.</p> </div>
</blockquote>
<p>Hi Anjali,</p>
<p>I will have a look and see whether it is possible to modify the AgentX code \
without reducing performance and without dropping support for large AgentX packets. \
BTW, the following commit increased the buffer size:<br> </p>
<p>c09140c934eb (&quot;CHANGES: snmpd: Increase maximum AgentX packet size to \
64kB.&quot;)</p> </blockquote>
<p>Hi Anjali,</p>
<p>A candidate fix has been checked in on the v5.8 and master branches. Please \
verify.</p> <p>Bart.<br>
</p>
</div>
</div>
</div>
</body>
</html>


[Attachment #4 (--===============8653023601690868616==)]


_______________________________________________
Net-snmp-coders mailing list
Net-snmp-coders@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/net-snmp-coders


[prev in list] [next in list] [prev in thread] [next in thread] 

Configure | About | News | Add a list | Sponsored by KoreLogic