Move pcap bundler group to metasploit-framework-pcap.gemspec

MSP-11578

This will allow Metasploit Pro to use the
metasploit-framework-pcap.gemspec to ensure it has the correct version of
gems that were previously only in metasploit-framework's Gemfile and so
weren't being checked for version compatibility when Pro used
metasploit-framework.gemspec.

Gemfile

@@ -37,9 +37,7 @@ group :development, :test do
 end
 
 group :pcap do
-  gem 'network_interface', '~> 0.0.1'
-  # For sniffer and raw socket modules
-  gem 'pcaprub'
+  gemspec name: 'metasploit-framework-pcap'
 end
 
 group :test do

Gemfile.lock

@@ -26,6 +26,9 @@ PATH
       metasploit-framework (= 4.10.1.pre.dev)
       metasploit_data_models (~> 0.21.1)
       pg (>= 0.11)
+    metasploit-framework-pcap (4.10.1.pre.dev)
+      network_interface (~> 0.0.1)
+      pcaprub
 
 GEM
   remote: https://rubygems.org/
@@ -231,8 +234,7 @@ DEPENDENCIES
   fivemat (= 1.2.1)
   metasploit-framework!
   metasploit-framework-db!
-  network_interface (~> 0.0.1)
-  pcaprub
+  metasploit-framework-pcap!
   pry
   rake (>= 10.0.0)
   rb-readline

metasploit-framework-pcap.gemspec

@@ -0,0 +1,32 @@
+# coding: utf-8
+
+# During build, the Gemfile is temporarily moved and
+# we must manually define the project root
+if ENV['MSF_ROOT']
+  lib = File.realpath(File.expand_path('lib', ENV['MSF_ROOT']))
+else
+  # have to use realpath as metasploit-framework is often loaded through a symlink and tools like Coverage and debuggers
+  # require realpaths.
+  lib = File.realpath(File.expand_path('../lib', __FILE__))
+end
+
+$LOAD_PATH.unshift(lib) unless $LOAD_PATH.include?(lib)
+require 'metasploit/framework/version'
+
+Gem::Specification.new do |spec|
+  spec.name          = 'metasploit-framework-pcap'
+  spec.version       = Metasploit::Framework::GEM_VERSION
+  spec.authors       = ['Metasploit Hackers']
+  spec.email         = ['metasploit-hackers@lists.sourceforge.net']
+  spec.summary       = 'metasploit-framework packet capture dependencies'
+  spec.description   = 'Gems needed to capture packets in metasploit-framework'
+  spec.homepage      = 'https://www.metasploit.com'
+  spec.license       = 'BSD-3-clause'
+
+  # no files, just dependencies
+  spec.files         = []
+
+  spec.add_runtime_dependency 'network_interface', '~> 0.0.1'
+  # For sniffer and raw socket modules
+  spec.add_runtime_dependency 'pcaprub'
+end