Add md5 and sha1 checksum support to Downloader.

Allows checksum validation on downloaded files via Util::Downloader
using MD5 and/or SHA1 checksums. This also integrates checksum validation
support with the shell provisioner for downloaded remote files.

lib/vagrant/errors.rb

@@ -340,6 +340,10 @@ module Vagrant
       error_key(:downloader_interrupted)
     end
 
+    class DownloaderChecksumError < VagrantError
+      error_key(:downloader_checksum_error)
+    end
+
     class EnvInval < VagrantError
       error_key(:env_inval)
     end

lib/vagrant/util/downloader.rb

@@ -1,7 +1,8 @@
 require "uri"
 
 require "log4r"
-
+require "digest/md5"
+require "digest/sha1"
 require "vagrant/util/busy"
 require "vagrant/util/platform"
 require "vagrant/util/subprocess"
@@ -18,6 +19,12 @@ module Vagrant
       #     Vagrant/1.7.4 (+https://www.vagrantup.com; ruby2.1.0)
       USER_AGENT = "Vagrant/#{VERSION} (+https://www.vagrantup.com; #{RUBY_ENGINE}#{RUBY_VERSION})".freeze
 
+      # Supported file checksum
+      CHECKSUM_MAP = {
+        :md5 => Digest::MD5,
+        :sha1 => Digest::SHA1
+      }.freeze
+
       attr_reader :source
       attr_reader :destination
 
@@ -52,6 +59,10 @@ module Vagrant
         @ui          = options[:ui]
         @client_cert = options[:client_cert]
         @location_trusted = options[:location_trusted]
+        @checksums   = {
+          :md5 => options[:md5],
+          :sha1 => options[:sha1]
+        }
       end
 
       # This executes the actual download, downloading the source file
@@ -161,6 +172,8 @@ module Vagrant
           end
         end
 
+        validate_download!(@source, @destination, @checksums)
+
         # Everything succeeded
         true
       end
@@ -178,6 +191,47 @@ module Vagrant
 
       protected
 
+      # Apply any checksum validations based on provided
+      # options content
+      #
+      # @param source [String] Source of file
+      # @param path [String, Pathname] local file path
+      # @param checksums [Hash] User provided options
+      # @option checksums [String] :md5 Compare MD5 checksum
+      # @option checksums [String] :sha1 Compare SHA1 checksum
+      # @return [Boolean]
+      def validate_download!(source, path, checksums)
+        CHECKSUM_MAP.each do |type, klass|
+          if checksums[type]
+            result = checksum_file(klass, path)
+            if checksums[type] != result
+              raise Errors::DownloaderChecksumError.new(
+                source: source,
+                path: path,
+                expected_checksum: checksums[type],
+                actual_checksum: result
+              )
+            end
+          end
+        end
+        true
+      end
+
+      # Generate checksum on given file
+      #
+      # @param digest_class [Class] Digest class to use for generating checksum
+      # @param path [String, Pathname] Path to file
+      # @return [String] hexdigest result
+      def checksum_file(digest_class, path)
+        digester = digest_class.new
+        File.open(path.to_s, 'rb') do |file|
+          while(data = file.read(1024))
+            digester << data
+          end
+        end
+        digester.hexdigest
+      end
+
       def execute_curl(options, subprocess_options, &data_proc)
         options = options.dup
         options << subprocess_options

plugins/provisioners/shell/config.rb

@@ -5,6 +5,8 @@ module VagrantPlugins
     class Config < Vagrant.plugin("2", :config)
       attr_accessor :inline
       attr_accessor :path
+      attr_accessor :md5
+      attr_accessor :sha1
       attr_accessor :env
       attr_accessor :upload_path
       attr_accessor :args
@@ -19,6 +21,8 @@ module VagrantPlugins
         @args                  = UNSET_VALUE
         @inline                = UNSET_VALUE
         @path                  = UNSET_VALUE
+        @md5                   = UNSET_VALUE
+        @sha1                  = UNSET_VALUE
         @env                   = UNSET_VALUE
         @upload_path           = UNSET_VALUE
         @privileged            = UNSET_VALUE
@@ -33,6 +37,8 @@ module VagrantPlugins
         @args                 = nil if @args == UNSET_VALUE
         @inline               = nil if @inline == UNSET_VALUE
         @path                 = nil if @path == UNSET_VALUE
+        @md5                  = nil if @md5 == UNSET_VALUE
+        @sha1                 = nil if @sha1 == UNSET_VALUE
         @env                  = {}  if @env == UNSET_VALUE
         @upload_path          = "/tmp/vagrant-shell" if @upload_path == UNSET_VALUE
         @privileged           = true if @privileged == UNSET_VALUE

plugins/provisioners/shell/provisioner.rb

@@ -177,7 +177,12 @@ module VagrantPlugins
           download_path.delete if download_path.file?
 
           begin
-            Vagrant::Util::Downloader.new(config.path, download_path).download!
+            Vagrant::Util::Downloader.new(
+              config.path,
+              download_path,
+              md5: config.md5,
+              sha1: config.sha1
+            ).download!
             ext    = File.extname(config.path)
             script = download_path.read
           ensure

templates/locales/en.yml

@@ -734,6 +734,13 @@ en:
       downloader_interrupted: |-
         The download was interrupted by an external signal. It did not
         complete.
+      downloader_checksum_error: |-
+        The calculated checksum of the requested file does not match the expected
+        checksum!
+
+        File source:         %{source}
+        Expected checksum:   %{expected_checksum}
+        Calculated checksum: %{actual_checksum}
       env_inval: |-
         Vagrant received an "EINVAL" error while attempting to set some
         environment variables. This is usually caused by the total size of your

test/unit/plugins/provisioners/shell/provisioner_test.rb

@@ -2,14 +2,19 @@ require File.expand_path("../../../../base", __FILE__)
 require Vagrant.source_root.join("plugins/provisioners/shell/provisioner")
 
 describe "Vagrant::Shell::Provisioner" do
+  include_context "unit"
 
+  let(:env){ isolated_environment }
   let(:machine) {
-    double(:machine).tap { |machine|
+    double(:machine, env: env, id: "ID").tap { |machine|
       machine.stub_chain(:config, :vm, :communicator).and_return(:not_winrm)
       machine.stub_chain(:communicate, :tap) {}
     }
   }
 
+  before do
+    allow(env).to receive(:tmp_path).and_return(Pathname.new("/dev/null"))
+  end
 
   context "with a script that contains invalid us-ascii byte sequences" do
     let(:config) {
@@ -37,4 +42,73 @@ describe "Vagrant::Shell::Provisioner" do
       }.not_to raise_error
     end
   end
+
+  context "with remote script" do
+
+    context "that does not have matching sha1 checksum" do
+      let(:config) {
+        double(
+          :config,
+          :args        => "doesn't matter",
+          :env         => {},
+          :upload_path => "arbitrary",
+          :remote?     => true,
+          :path        => "http://example.com/script.sh",
+          :binary      => false,
+          :md5         => nil,
+          :sha1        => 'EXPECTED_VALUE'
+        )
+      }
+
+      let(:file){ double("file") }
+      let(:digest){ double("digest") }
+      before do
+        Vagrant::Util::Downloader.any_instance.should_receive(:execute_curl).and_return(true)
+        expect(File).to receive(:open).with(%r{/dev/null/.+}, "rb").and_yield(file).once
+        allow(File).to receive(:open).and_call_original
+        expect(file).to receive(:read).and_return(nil)
+        expect(Digest::SHA1).to receive(:new).and_return(digest)
+        expect(digest).to receive(:hexdigest).and_return('INVALID_VALUE')
+      end
+
+      it "should raise an exception" do
+        vsp = VagrantPlugins::Shell::Provisioner.new(machine, config)
+
+        expect{ vsp.provision }.to raise_error(Vagrant::Errors::DownloaderChecksumError)
+      end
+    end
+
+    context "that does not have matching md5 checksum" do
+      let(:config) {
+        double(
+          :config,
+          :args        => "doesn't matter",
+          :env         => {},
+          :upload_path => "arbitrary",
+          :remote?     => true,
+          :path        => "http://example.com/script.sh",
+          :binary      => false,
+          :md5         => 'EXPECTED_VALUE',
+          :sha1        => nil
+        )
+      }
+
+      let(:file){ double("file") }
+      let(:digest){ double("digest") }
+      before do
+        Vagrant::Util::Downloader.any_instance.should_receive(:execute_curl).and_return(true)
+        expect(File).to receive(:open).with(%r{/dev/null/.+}, "rb").and_yield(file).once
+        allow(File).to receive(:open).and_call_original
+        expect(file).to receive(:read).and_return(nil)
+        expect(Digest::MD5).to receive(:new).and_return(digest)
+        expect(digest).to receive(:hexdigest).and_return('INVALID_VALUE')
+      end
+
+      it "should raise an exception" do
+        vsp = VagrantPlugins::Shell::Provisioner.new(machine, config)
+
+        expect{ vsp.provision }.to raise_error(Vagrant::Errors::DownloaderChecksumError)
+      end
+    end
+  end
 end

test/unit/vagrant/util/downloader_test.rb

@@ -93,6 +93,107 @@ describe Vagrant::Util::Downloader do
         expect(subject.download!).to be_true
       end
     end
+
+    context "with checksum" do
+      let(:checksum_expected_value){ 'MD5_CHECKSUM_VALUE' }
+      let(:checksum_invalid_value){ 'INVALID_VALUE' }
+      let(:digest){ double("digest") }
+      let(:file){ double("file") }
+
+      before do
+        allow(digest).to receive(:<<)
+        allow(File).to receive(:open).and_yield(file)
+        allow(file).to receive(:read).and_return(nil)
+      end
+
+      [Digest::MD5, Digest::SHA1].each do |klass|
+        short_name = klass.to_s.split("::").last.downcase
+
+        context "using #{short_name} digest" do
+          subject { described_class.new(source, destination, short_name.to_sym => checksum_expected_value) }
+
+          context "that matches expected value" do
+            before do
+              expect(klass).to receive(:new).and_return(digest)
+              expect(digest).to receive(:hexdigest).and_return(checksum_expected_value)
+            end
+
+            it "should not raise an exception" do
+              expect(subject.download!).to be_true
+            end
+          end
+
+          context "that does not match expected value" do
+            before do
+              expect(klass).to receive(:new).and_return(digest)
+              expect(digest).to receive(:hexdigest).and_return(checksum_invalid_value)
+            end
+
+            it "should raise an exception" do
+              expect{ subject.download! }.to raise_error(Vagrant::Errors::DownloaderChecksumError)
+            end
+          end
+        end
+      end
+
+      context "using both md5 and sha1 digests" do
+        context "that both match expected values" do
+          subject { described_class.new(source, destination, md5: checksum_expected_value, sha1: checksum_expected_value) }
+
+          before do
+            expect(Digest::MD5).to receive(:new).and_return(digest)
+            expect(Digest::SHA1).to receive(:new).and_return(digest)
+            expect(digest).to receive(:hexdigest).and_return(checksum_expected_value).exactly(2).times
+          end
+
+          it "should not raise an exception" do
+            expect(subject.download!).to be_true
+          end
+        end
+
+        context "that only sha1 matches expected value" do
+          subject { described_class.new(source, destination, md5: checksum_invalid_value, sha1: checksum_expected_value) }
+
+          before do
+            allow(Digest::MD5).to receive(:new).and_return(digest)
+            allow(Digest::SHA1).to receive(:new).and_return(digest)
+            expect(digest).to receive(:hexdigest).and_return(checksum_expected_value).at_least(:once)
+          end
+
+          it "should raise an exception" do
+            expect{ subject.download! }.to raise_error(Vagrant::Errors::DownloaderChecksumError)
+          end
+        end
+
+        context "that only md5 matches expected value" do
+          subject { described_class.new(source, destination, md5: checksum_expected_value, sha1: checksum_invalid_value) }
+
+          before do
+            allow(Digest::MD5).to receive(:new).and_return(digest)
+            allow(Digest::SHA1).to receive(:new).and_return(digest)
+            expect(digest).to receive(:hexdigest).and_return(checksum_expected_value).at_least(:once)
+          end
+
+          it "should raise an exception" do
+            expect{ subject.download! }.to raise_error(Vagrant::Errors::DownloaderChecksumError)
+          end
+        end
+
+        context "that none match expected value" do
+          subject { described_class.new(source, destination, md5: checksum_invalid_value, sha1: checksum_invalid_value) }
+
+          before do
+            allow(Digest::MD5).to receive(:new).and_return(digest)
+            allow(Digest::SHA1).to receive(:new).and_return(digest)
+            expect(digest).to receive(:hexdigest).and_return(checksum_expected_value).at_least(:once)
+          end
+
+          it "should raise an exception" do
+            expect{ subject.download! }.to raise_error(Vagrant::Errors::DownloaderChecksumError)
+          end
+        end
+      end
+    end
   end
 
   describe "#head" do

website/source/docs/provisioning/shell.html.md

@@ -79,6 +79,10 @@ The remainder of the available options are optional:
   enable auto-login for Windows as the user must be logged in for interactive
   mode to work.
 
+* `md5` (string) - MD5 checksum used to validate remotely downloaded shell files.
+
+* `sha1` (string) - SHA1 checksum used to validate remotely downloaded shell files.
+
 <a name="inline-scripts"></a>
 ## Inline Scripts