From ed99f2bc0124a49ab76928bfe92450e02ff72bb2 Mon Sep 17 00:00:00 2001
From: nixawk <hap.ddup@gmail.com>
Date: Fri, 8 Jan 2016 22:22:00 +0800
Subject: [PATCH 1/3] Fix dns labels/names size limits

---
 lib/net/dns/names/names.rb | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/net/dns/names/names.rb b/lib/net/dns/names/names.rb
index d65c8bf293..60b3831351 100644
--- a/lib/net/dns/names/names.rb
+++ b/lib/net/dns/names/names.rb
@@ -46,8 +46,8 @@ module Net # :nodoc:
       end
       
       def pack_name(name)
-        if name.size > 63
-          raise ArgumentError, "Label data cannot exceed 63 chars"
+        if name.size > 255
+          raise ArgumentError, "Name data cannot exceed 255 chars"
         end
         arr = name.split(".")
         str = ""

From dceb0f5ea928ada56b658f311e23c440b516687c Mon Sep 17 00:00:00 2001
From: nixawk <hap.ddup@gmail.com>
Date: Sat, 9 Jan 2016 11:39:56 +0800
Subject: [PATCH 2/3] check dns labels size limits

---
 lib/net/dns/names/names.rb | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/lib/net/dns/names/names.rb b/lib/net/dns/names/names.rb
index 60b3831351..b483368877 100644
--- a/lib/net/dns/names/names.rb
+++ b/lib/net/dns/names/names.rb
@@ -52,6 +52,9 @@ module Net # :nodoc:
         arr = name.split(".")
         str = ""
         arr.each do |elem|
+          if elem.size > 63
+            raise ArgumentError, "Label data cannot exceed 63 chars"
+          end
           str += [elem.size,elem].pack("Ca*")
         end
         str += [0].pack("C")

From 46d4b533f3e41992695d00d5d62c40faff261fc2 Mon Sep 17 00:00:00 2001
From: wchen-r7 <wei_chen@rapid7.com>
Date: Thu, 31 Mar 2016 11:29:30 -0500
Subject: [PATCH 3/3] Add rspec for lib/net/dns/names/names.rb

---
 spec/lib/net/dns/names/names_spec.rb | 129 +++++++++++++++++++++++++++
 1 file changed, 129 insertions(+)
 create mode 100644 spec/lib/net/dns/names/names_spec.rb

diff --git a/spec/lib/net/dns/names/names_spec.rb b/spec/lib/net/dns/names/names_spec.rb
new file mode 100644
index 0000000000..96ea39a86f
--- /dev/null
+++ b/spec/lib/net/dns/names/names_spec.rb
@@ -0,0 +1,129 @@
+require 'msf/core'
+
+RSpec.describe Net::DNS::Names do
+  subject do
+    obj = Object.new
+    obj.extend(described_class)
+  end
+
+  describe '#dn_expand' do
+    context 'when offset is great than packet length' do
+      let(:packet) do
+        'AAAAA'
+      end
+
+      let(:offset) do
+        10
+      end
+
+      it 'raises an ExpandError exception' do
+        expect { subject.dn_expand(packet, offset) }.to raise_exception(ExpandError)
+      end
+    end
+
+    context 'when packet length is less than offset + INT16SZ' do
+      let(:packet) do
+        "\xc0"
+      end
+
+      let(:offset) do
+        0
+      end
+
+      it 'raises an ExpandError exception' do
+        expect { subject.dn_expand(packet, offset) }.to raise_exception(ExpandError)
+      end
+    end
+
+    context 'when packet length is less than offset + packet length' do
+      let(:packet) do
+        'AAAAA'
+      end
+
+      let(:offset) do
+        4
+      end
+
+      it 'raises an ExpandError exception' do
+        expect { subject.dn_expand(packet, offset) }.to raise_exception(ExpandError)
+      end
+    end
+  end
+
+  describe '#pack_name' do
+    context 'when name data size is larger than 255 bytes' do
+      let(:name) do
+        'A' * (255+1)
+      end
+
+      it 'raises an ArgumentError exception' do
+        expect { subject.pack_name(name) }.to raise_exception(ArgumentError)
+      end
+    end
+
+    context 'when label data is larger than 63 bytes' do
+      let(:name) do
+        'A' * (63+1) + '.'
+      end
+
+      it 'raises an ArgumentError exception' do
+        expect { subject.pack_name(name) }.to raise_exception(ArgumentError)
+      end 
+    end
+  end
+
+  describe '#names_array' do
+    let(:name) do
+      "AAA.AAA"
+    end
+
+    it 'returns an Array' do
+      expect(subject.names_array(name)).to be_kind_of(Array)
+    end
+  end
+
+  describe '#dn_comp' do
+    let(:name) do
+      'AAAA'
+    end
+
+    let(:offset) do
+      0
+    end
+
+    let(:compnames) do
+      {}
+    end
+
+    it 'returns 3 values' do
+      v = subject.dn_comp(name, offset, compnames)
+      expect(v.length).to eq(3)
+      expect(v[0]).to be_kind_of(String)
+      expect(v[1]).to be_kind_of(Fixnum)
+      expect(v[2]).to be_kind_of(Hash)
+    end
+  end
+
+  describe '#valid?' do
+    context 'when FQDN is valid' do
+      let(:fqdn) do
+        'example.com'
+      end
+
+      it 'returns the FQDN' do
+        expect(subject.valid?(fqdn)).to eq(fqdn)
+      end
+
+    end
+
+    context 'when FQDN is not valid' do
+      let(:fqdn) do
+        'INVALID'
+      end
+
+      it 'raises ArgumentError exception' do
+        expect { subject.valid?(fqdn) }.to raise_exception(ArgumentError)
+      end
+    end
+  end
+end
\ No newline at end of file