Require MTU passed as positive integer; coerce when parsing

Author: runejuhl

lib/puppet/provider/network_config/interfaces.rb

@@ -226,7 +226,7 @@ def self.parse_file(_filename, contents)
             case key # rubocop:disable Metrics/BlockNesting
             when 'address' then         Instance[name].ipaddress    = val
             when 'netmask' then         Instance[name].netmask      = val
-            when 'mtu' then             Instance[name].mtu          = val
+            when 'mtu' then             Instance[name].mtu          = val.to_i
             else Instance[name].options[key] << val
             end
           end

lib/puppet/type/network_config.rb

@@ -86,15 +86,8 @@
     desc 'The Maximum Transmission Unit size to use for the interface'
     validate do |value|
       # reject floating point and negative integers
-      # XXX this lets 1500.0 pass
-      if value.is_a? Numeric
-        unless value.integer?
-          raise ArgumentError, "#{value} is not a valid mtu (must be a positive integer)"
-        end
-      else
-        unless value =~ %r{^\d+$}
-          raise ArgumentError, "#{value} is not a valid mtu (must be a positive integer)"
-        end
+      unless value.is_a?(Numeric) && value.integer?
+        raise ArgumentError, "#{value} is not a valid mtu (must be a positive integer)"
       end
 
       # Intel 82598 & 82599 chips support MTUs up to 16110; is there any
@@ -106,7 +99,7 @@
       # is 42 with a 802.1q header and 46 without.
       min_mtu = 42
       max_mtu = 65_536
-      unless (min_mtu..max_mtu).cover?(value.to_i)
+      unless min_mtu <= value && value <= max_mtu
         raise ArgumentError, "#{value} is not in the valid mtu range (#{min_mtu} .. #{max_mtu})"
       end
     end

spec/unit/type/network_config_spec.rb

@@ -140,26 +140,14 @@
     end
 
     describe 'mtu' do
-      it 'validates a tiny mtu size' do
-        Puppet::Type.type(:network_config).new(name: 'yay', mtu: '42')
-      end
-
       it 'validates a tiny mtu size as a number' do
         Puppet::Type.type(:network_config).new(name: 'yay', mtu: 42)
       end
 
-      it 'validates a normal mtu size' do
-        Puppet::Type.type(:network_config).new(name: 'yay', mtu: '1500')
-      end
-
       it 'validates a normal mtu size as a number' do
         Puppet::Type.type(:network_config).new(name: 'yay', mtu: 1500)
       end
 
-      it 'validates a large mtu size' do
-        Puppet::Type.type(:network_config).new(name: 'yay', mtu: '16384')
-      end
-
       it 'validates a large mtu size as a number' do
         Puppet::Type.type(:network_config).new(name: 'yay', mtu: 16_384)
       end
@@ -170,63 +158,39 @@
         end.to raise_error(%r{must be a positive integer})
       end
 
-      it 'fails on values < 42' do
-        expect do
-          Puppet::Type.type(:network_config).new(name: 'yay', mtu: '41')
-        end.to raise_error(%r{is not in the valid mtu range})
-      end
-
       it 'fails on numeric values < 42' do
         expect do
           Puppet::Type.type(:network_config).new(name: 'yay', mtu: 41)
         end.to raise_error(%r{is not in the valid mtu range})
       end
 
-      it 'fails on zero' do
-        expect do
-          Puppet::Type.type(:network_config).new(name: 'yay', mtu: '0')
-        end.to raise_error(%r{is not in the valid mtu range})
-      end
-
       it 'fails on numeric zero' do
         expect do
           Puppet::Type.type(:network_config).new(name: 'yay', mtu: 0)
         end.to raise_error(%r{is not in the valid mtu range})
       end
 
-      it 'fails on values > 65536' do
-        expect do
-          Puppet::Type.type(:network_config).new(name: 'yay', mtu: '65537')
-        end.to raise_error(%r{is not in the valid mtu range})
-      end
-
       it 'fails on numeric values > 65536' do
         expect do
           Puppet::Type.type(:network_config).new(name: 'yay', mtu: 65_537)
         end.to raise_error(%r{is not in the valid mtu range})
       end
 
-      it 'fails on negative values' do
-        expect do
-          Puppet::Type.type(:network_config).new(name: 'yay', mtu: '-1500')
-        end.to raise_error(%r{is not a valid mtu})
-      end
-
       it 'fails on negative numbers' do
         expect do
           Puppet::Type.type(:network_config).new(name: 'yay', mtu: -1500)
         end.to raise_error(%r{is not in the valid mtu range})
       end
 
-      it 'fails on non-integer values' do
+      it 'fails on numeric non-integer values' do
         expect do
-          Puppet::Type.type(:network_config).new(name: 'yay', mtu: '1500.1')
+          Puppet::Type.type(:network_config).new(name: 'yay', mtu: 1500.1)
         end.to raise_error(%r{must be a positive integer})
       end
 
-      it 'fails on numeric non-integer values' do
+      it 'fails on integers passed as strings' do
         expect do
-          Puppet::Type.type(:network_config).new(name: 'yay', mtu: 1500.1)
+          Puppet::Type.type(:network_config).new(name: 'yay', mtu: '1500.1')
         end.to raise_error(%r{must be a positive integer})
       end
     end