From 0f19d44c1d03f9db0a68b8a3c3220706dd682ce0 Mon Sep 17 00:00:00 2001
From: Jean Benoit <jean@unistra.fr>
Date: Fri, 4 Sep 2020 19:30:21 +0100
Subject: [PATCH] contrib: snmptest.pl SNMPwalk can't access to all
 variables/wrong sort
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Large quantity of data will be missing when snmptest.pl is used.  The reason
is a sort in lexicographic order:

    $ snmpwalk -v2c -c public localhost .1.3.6.1.4.1.2021.250.255 |head
    iso.3.6.1.4.1.2021.250.255.2.1 = STRING:  "10.4.52.1"
    iso.3.6.1.4.1.2021.250.255.2.10 = STRING: "192.168.35.64"
    iso.3.6.1.4.1.2021.250.255.2.100 = STRING: "192.168.196.1"
    iso.3.6.1.4.1.2021.250.255.2.101 = STRING: "192.168.198.1"
    iso.3.6.1.4.1.2021.250.255.2.102 = STRING: "192.168.209.225"
    iso.3.6.1.4.1.2021.250.255.2.103 = STRING: "192.168.209.241"

SNMPGetNext after "root.2.1" should give "root.2.2".  Thus, lots of
variables are missing.

The function is now dependant on a CPAN module NetSNMP::OID, (debian/ubuntu
package is called libsnmp-perl).  This is probably not the most efficient
way to do it: walking the whole tree will be much slower.

Signed-off-by: Jean Benoit <jean@unistra.fr>
---
 THANKS              |  1 +
 contrib/snmptest.pl | 13 ++++++++++---
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/THANKS b/THANKS
index f5fd050..4bb123d 100644
--- a/THANKS
+++ b/THANKS
@@ -48,3 +48,4 @@ Sebastián Cramatte
 Mark Sangster
 Brent Swingle
 Mathieu Morier
+Jean Benoit
diff --git a/contrib/snmptest.pl b/contrib/snmptest.pl
index c77b882..54093c7 100644
--- a/contrib/snmptest.pl
+++ b/contrib/snmptest.pl
@@ -23,9 +23,10 @@
 #    you set $dbg to 1 then output will be generated in /tmp.
 
 use strict;
+use NetSNMP::OID;
 
 # Version info:
-my $SNMPver = "snmp1.0";
+my $SNMPver = "snmp1.1";
 my $DHCPver = "dhcp1.0";
 my $VERSION = "$SNMPver/$DHCPver";
 #
@@ -193,7 +194,7 @@ sub ParseDataFile () {
    }
    close IN;
    if ($dbg) {
-      foreach (sort @validoidlist) { print DBG "ValidOID: $_\n"; }
+      foreach (sort Oidcmp @validoidlist) { print DBG "ValidOID: $_\n"; }
    }
 
    if ($dbg) {
@@ -370,7 +371,7 @@ sub GetData ($) {
 
       @userquery = split (/\./, $userqueryoid);
       my $found = 0;
-      foreach (sort @validoidlist) {
+      foreach (sort Oidcmp @validoidlist) {
          $next = $_;
          print DBG "Comparing $userqueryoid vs. $_\n" if $dbg;
          @validoid = split (/\./, $_);
@@ -432,6 +433,12 @@ sub Pong {
    $line = 0;
 }
 
+sub Oidcmp {
+   my $oida = new NetSNMP::OID($a);
+   my $oidb = new NetSNMP::OID($b);
+   snmp_oid_compare($oida, $oidb);
+}
+
 ################################## START ##################################
 #
 # Main