Add SNMP scan forking feature

etc/ocsinventory-agent/modules.conf

@@ -6,6 +6,7 @@
 use Ocsinventory::Agent::Modules::Download;
 use Ocsinventory::Agent::Modules::SnmpScan;
 #use Ocsinventory::Agent::Modules::LocalSnmpScan;
+use Ocsinventory::Agent::Modules::SnmpFork;
 
 # DO NOT REMOVE the 1;
 1;

lib/Ocsinventory/Agent/Modules/SnmpFork.pm

@@ -0,0 +1,129 @@
+###############################################################################
+## OCSINVENTORY-NG
+## Copyleft OCS Inventory NG Team
+## Web : http://www.ocsinventory-ng.org
+##
+## Wrapper for SNMP scan (local and online mode) that handles the forking of the
+## SNMP scan process
+##
+## This code is open source and may be copied and modified as long as the source
+## code is always made freely available.
+## Please refer to the General Public Licence http://www.gnu.org/ or Licence.txt
+################################################################################
+
+package Ocsinventory::Agent::Modules::SnmpFork;
+
+use strict;
+no strict 'refs';
+no strict 'subs';
+use warnings;
+
+use XML::Simple;
+use Digest::MD5;
+
+
+# launch the SNMP scan in a forked process
+# takes the native scan function to call, subnets to scan, nb of forks and self
+sub fork_snmpscan {
+    my ($scan_function, $nets_to_scan, $fork_count, $self) = @_;
+
+    my $logger = $self->{logger};
+
+    # get fork count from config or calculate it
+    $fork_count = $fork_count // 0;
+    if ($fork_count !~ /^\d+$/ || $fork_count <= 0) {
+        $logger->debug("Invalid fork_nb value in config: $fork_count. Falling back to calculated value.");
+        $fork_count = get_forks_nb();
+    }
+
+    # split nets_to_scan among forks
+    my @split_nets_to_scan = split_array_across_forks($nets_to_scan, $fork_count);
+
+    my @pipes;
+    my @aggregated_content;
+
+    # fork processes
+    for (my $i = 0; $i < $fork_count; $i++) {
+        # pipe
+        my ($reader, $writer);
+        pipe($reader, $writer);
+        $reader->autoflush(1);
+        $writer->autoflush(1);
+        push @pipes, $reader;
+
+        my $pid = fork();
+        if ($pid) {
+            # parent
+            close $writer;
+        } elsif (defined $pid) {
+            # child
+            close $reader;
+            my $subnets_to_scan = $split_nets_to_scan[$i];
+
+            # calling scan function
+            my $xml_result = $scan_function->($self, $subnets_to_scan);
+
+            # write xml result to pipe
+            print $writer $xml_result;
+            close $writer;
+            exit 0;
+        } else {
+            $logger->error("Fork failed: $!");
+        }
+    }
+
+    # parent process: read and aggregate XML from pipes
+    foreach my $reader (@pipes) {
+        while (my $line = <$reader>) {
+            push @aggregated_content, $line;
+        }
+        close $reader;
+    }
+
+    # wait for all child processes to finish
+    my $child_pid;
+    while (($child_pid = waitpid(-1, 0)) > 0) {
+        $logger->debug("Child process $child_pid finished with exit code $?");
+    }
+
+    # aggregated content into one content block
+    my $content_block = join("", @aggregated_content);
+
+    # final XML structure
+    my $final_xml = <<"END_XML";
+<?xml version="1.0" encoding="UTF-8"?>
+<REQUEST>
+  <CONTENT>
+    $content_block
+  </CONTENT>
+  <DEVICEID>$self->{context}->{config}->{deviceid}</DEVICEID>
+  <QUERY>SNMP</QUERY>
+</REQUEST>
+END_XML
+
+    return $final_xml;
+}
+
+# split the array of IPs into even portions for each fork
+sub split_array_across_forks {
+    my ($nets_to_scan, $fork_count) = @_;
+    my @split_nets;
+
+    my $i = 0;
+    foreach my $subnet (@$nets_to_scan) {
+        push(@{$split_nets[$i]}, $subnet);
+        $i = ($i + 1) % $fork_count;
+    }
+
+    return @split_nets;
+}
+
+# default nb of forks is nb of cores
+sub get_forks_nb {
+    my $cores = `nproc`;
+    chomp($cores);
+    return $cores;
+}
+
+
+1;

lib/Ocsinventory/Agent/Modules/SnmpScan.pm

@@ -9,6 +9,7 @@
 ################################################################################
 
 package Ocsinventory::Agent::Modules::SnmpScan;
+use Ocsinventory::Agent::Modules::SnmpFork ();
 
 use strict;
 no strict 'refs';
@@ -55,6 +56,12 @@ sub snmpscan_start_handler {
 
     $logger->debug("Calling snmp_start_handler");
 
+    if ($config->{forking_enabled}) {
+        $logger->debug("SNMP Forking is enabled");
+    } else {
+        $logger->debug("SNMP Forking is disabled");
+    }
+
     # Disabling module if local mode
     if ($config->{stdout} || $config->{local}) {
         $self->{disabled} = 1;
@@ -154,23 +161,7 @@ sub snmpscan_end_handler {
 
     # We get the config
     my $config = $self->{context}->{config};
-    # Load setting from the config file
-    my $configagent = new Ocsinventory::Agent::Config;
-    $configagent->loadUserParams();
-
-    my $communities=$self->{communities};
 
-    if ( ! defined ($communities ) ) {
-        $logger->debug("We have no Community from server, we use default public community");
-        $communities=[{VERSION=>"2c",NAME=>"public"}];
-    }
-
-    my ($name,$comm,$error,$system_oid);
-
-    # Initalising the XML properties 
-    my $snmp_inventory = $self->{inventory};
-    $snmp_inventory->{xmlroot}->{QUERY} = ['SNMP'];
-    $snmp_inventory->{xmlroot}->{DEVICEID} = [$self->{context}->{config}->{deviceid}];
 
     # Scanning network
     $logger->debug("Snmp: Scanning network");
@@ -182,15 +173,65 @@ sub snmpscan_end_handler {
         my $net_to_scan = [];
         $self->snmp_ip_scan($net_to_scan);
     } else {
-        foreach my $net_to_scan ( @$nets_to_scan ){
+        foreach my $net_to_scan (@$nets_to_scan) {
             $self->snmp_ip_scan($net_to_scan);
         }
     }
     $logger->debug("Snmp: Ending Scanning network");
 
+    my $xml_inventory;
+    if ($config->{forking_enabled}) {
+        $xml_inventory = Ocsinventory::Agent::Modules::SnmpFork::fork_snmpscan(\&perform_snmp_scan, $self->{netdevices}, $config->{fork_count}, $self);
+    } else {
+        $xml_inventory = $self->perform_snmp_scan();
+    }
+
+    $self->handleXml($xml_inventory);
+
+    $logger->debug("End snmp_end_handler :)");
+}
+
+sub perform_snmp_scan {
+    my $self = shift;
+    my $logger = $self->{logger};
+    my $common = $self->{context}->{common};
+    my $network = $self->{context}->{network};
+
     # Begin scanning ip tables 
     my $ip=$self->{netdevices};
 
+    # identify the process
+    my $forked = 0;
+    if ($self->{context}->{config}->{forking_enabled}) {
+        $forked = 1;
+        $ip = shift;
+    }
+
+    my $communities=$self->{communities};
+
+    if ( ! defined ($communities ) ) {
+        $logger->debug("We have no Community from server, we use default public community");
+        $communities=[{VERSION=>"2c",NAME=>"public"}];
+    }
+    my ($name,$comm,$error,$system_oid);
+
+    # Load setting from the config file
+    my $configagent = new Ocsinventory::Agent::Config;
+    $configagent->loadUserParams();
+
+    # Initalising the XML properties 
+    my $snmp_inventory = $self->{inventory};
+    $snmp_inventory->{xmlroot}->{QUERY} = ['SNMP'];
+    $snmp_inventory->{xmlroot}->{DEVICEID} = [$self->{context}->{config}->{deviceid}];
+
+
+    my $pidlog;
+    if ($forked) {
+        $pidlog = "[$$]";
+    } else {
+        $pidlog = "";
+    }
+
     foreach my $device ( @$ip ) {
         my $session = undef;
         my $oid_condition = undef;
@@ -200,7 +241,7 @@ sub snmpscan_end_handler {
         my $snmp_condition_value = undef;
         my $regex = undef;
 
-        $logger->debug("Scanning $device->{IPADDR} device");
+        $logger->debug("$pidlog Scanning device $device->{IPADDR} device");
         # Search for the good snmp community in the table community
         LIST_SNMP: foreach $comm ( @$communities ) {
             # Test if we use SNMP v3
@@ -272,7 +313,7 @@ sub snmpscan_end_handler {
                 );
             };
             unless (defined($session)) {
-                $logger->error("Snmp INFO: $error");
+                $logger->error("$pidlog Snmp INFO: $error");
             } else {
                 $self->{snmp_session}=$session;
 
@@ -361,17 +402,31 @@ sub snmpscan_end_handler {
         }
     }
 
-    $logger->info("No more SNMP device to scan"); 
-
-    # Formatting the XML and sendig it to the server
-    my $content = XMLout( $snmp_inventory->{xmlroot},  RootName => 'REQUEST' , XMLDecl => '<?xml version="1.0" encoding="UTF-8"?>', SuppressEmpty => undef );
+    $logger->info("$pidlog No more SNMP device to scan"); 
+    my $clean_content;
+    my $content;
+    if ($forked) {
+        $content = XMLout($snmp_inventory->{xmlroot}, RootName => 'REQUEST', XMLDecl => '<?xml version="1.0" encoding="UTF-8"?>', SuppressEmpty => undef);
+        $content = extract_content_tag($content);
+        $logger->debug("$pidlog Sending XML content to parent process");
+    } else {
+        # Formatting the XML and sendig it to the server
+        $content = XMLout( $snmp_inventory->{xmlroot},  RootName => 'REQUEST' , XMLDecl => '<?xml version="1.0" encoding="UTF-8"?>', SuppressEmpty => undef );
+    }
 
     #Cleaning XML to delete unprintable characters
-    my $clean_content = $common->cleanXml($content);
-
-    $self->handleXml($clean_content);
+    $clean_content = $common->cleanXml($content);
+
+    return $clean_content;
+}
 
-    $logger->debug("End snmp_end_handler :)");
+# extract CONTENT tag (used in perform_snmp_scan for forking)
+sub extract_content_tag {
+    my ($xml_string) = @_;
+    if ($xml_string =~ m|<CONTENT>(.*?)</CONTENT>|s) {
+        return $1;
+    }
+    return '';
 }
 
 sub snmp_ip_scan {
@@ -402,7 +457,7 @@ sub snmp_ip_scan {
             $ping->close();
 
         } elsif ($snmp_scan_type eq 'NMAP' && $common->can_load('Nmap::Parser')) {
-            $logger->debug("Scannig $net_to_scan with nmap");
+            $logger->debug("Scanning $net_to_scan with nmap");
             my $nmaparser = Nmap::Parser->new;
 
             $nmaparser->parsescan("nmap","-sn",$net_to_scan);

postinst.pl

@@ -458,6 +458,8 @@
 print MODULE "\n";
 print MODULE "#use Ocsinventory::Agent::Modules::LocalSnmpScan;\n";
 print MODULE "\n";
+print MODULE "use Ocsinventory::Agent::Modules::SnmpFork;\n";
+print MODULE "\n";
 print MODULE "# DO NOT REMOVE THE 1;\n";
 print MODULE "1;\n";
 close MODULE;