From bf52d27bb383f394ca1e4d66a9e351622c09898f Mon Sep 17 00:00:00 2001
From: Wolfgang Bumiller <w.bumiller@proxmox.com>
Date: Fri, 16 Oct 2015 15:53:49 +0200
Subject: [PATCH] network: IP_from_cidr and is_ip_in_cidr helpers

---
 src/PVE/Network.pm | 33 +++++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)

diff --git a/src/PVE/Network.pm b/src/PVE/Network.pm
index 34a280f..024b9b4 100644
--- a/src/PVE/Network.pm
+++ b/src/PVE/Network.pm
@@ -9,6 +9,8 @@ use File::Basename;
 use IO::Socket::IP;
 use POSIX qw(ECONNREFUSED);
 
+use Net::IP;
+
 # host network related utility functions
 
 our $ipv4_reverse_mask = [
@@ -467,4 +469,35 @@ sub tcp_ping {
     return $result;
 }
 
+sub IP_from_cidr {
+    my ($cidr, $version) = @_;
+
+    return if $cidr !~ m!^(\S+?)/(\S+)$!;
+    my ($ip, $prefix) = ($1, $2);
+
+    my $ipobj = Net::IP->new($ip, $version);
+    return if !$ipobj;
+
+    $version = $ipobj->version();
+
+    my $binmask = Net::IP::ip_get_mask($prefix, $version);
+    return if !$binmask;
+
+    my $masked_binip = $ipobj->binip() & $binmask;
+    my $masked_ip = Net::IP::ip_bintoip($masked_binip, $version);
+    return Net::IP->new("$masked_ip/$prefix");
+}
+
+sub is_ip_in_cidr {
+    my ($ip, $cidr, $version) = @_;
+
+    my $cidr_obj = IP_from_cidr($cidr, $version);
+    return undef if !$cidr_obj;
+
+    my $ip_obj = Net::IP->new($ip, $version);
+    return undef if !$ip_obj;
+
+    return $cidr_obj->overlaps($ip_obj) == $Net::IP::IP_B_IN_A_OVERLAP;
+}
+
 1;
-- 
2.39.2