Allow Masscan.scan to accept no arguments and only a block.

* Use the block style of `Masscan.scan` in the `ronin-masscan new`
  command output.

README.md

@@ -115,6 +115,12 @@ require 'ronin/masscan'
 
 output_file = Ronin::Masscan.scan('192.168.1.1', ports: [80,443])
 # => #<Masscan::OutputFile:...>
+
+output_file = Ronin::Masscan.scan do |masscan|
+  masscan.ports = [80,443]
+  masscan.ips   = '192.168.1.1'
+end
+# => #<Masscan::OutputFile:...>
 ```
 
 Accessing the masscan scan data:

data/templates/script.rb.erb

@@ -9,26 +9,26 @@ output_file = Ronin::Masscan.parse(<%= @output_file.inspect %>)
 output_file = Ronin::Masscan.parse(ARGV[0])
 <%-   end -%>
 <%- else -%>
-output_file = Ronin::Masscan.scan(
+output_file = Ronin::Masscan.scan do |masscan|
 <%-   case @ips.length -%>
 <%-   when 0 -%>
-  *ARGV,
+  masscan.ips         = ARGV
 <%-   when 1 -%>
-  <%= @ips[0].inspect %>,
+  masscan.ips         = <%= @ips[0].inspect %>
 <%-   else -%>
-  *<%= @ips.inspect %>,
+  masscan.ips         = <%= @ips.inspect %>
 <%-   end -%>
 <%-   if @ports -%>
-  ports: <%= @ports.inspect %>,
+  masscan.ports       = <%= @ports.inspect %>
 <%-   else -%>
-  # ports: [22, 80, 443, 8000..9000],
+  # masscan.ports       = [22, 80, 443, 8000..9000]
 <%-   end -%>
 <%-   if @output_file -%>
-  output_file: <%= @output_file.inspect %>
+  masscan.output_file = <%= @output_file.inspect %>
 <%-   else -%>
-  # output_file: "path/to/masscan.bin"
+  # masscan.output_file = "path/to/masscan.bin"
 <%-   end -%>
-)
+end
 <%- end -%>
 <% if @features[:printing] -%>
 

lib/ronin/masscan.rb

@@ -61,12 +61,10 @@ module Masscan
     # @api public
     #
     def self.scan(*ips,**kwargs,&block)
-      if ips.empty?
-        raise(ArgumentError,"must specify at least one IP address")
-      end
-
       masscan = ::Masscan::Command.new(ips: ips, **kwargs,&block)
 
+      masscan.ips ||= ips
+
       unless masscan.output_file
         FileUtils.mkdir_p(CACHE_DIR)
         tempfile = Tempfile.new(['masscan', '.json'], CACHE_DIR)

spec/cli/commands/new_spec.rb

@@ -147,18 +147,18 @@
       subject.run(path)
     end
 
-    it "must generate a new file containing a new `Ronin::Masscan.scan(...)`" do
+    it "must generate a new file containing a new `Ronin::Masscan.scan`" do
       expect(File.read(path)).to eq(
         <<~RUBY
           #!/usr/bin/env ruby
 
           require 'ronin/masscan'
 
-          output_file = Ronin::Masscan.scan(
-            *ARGV,
-            # ports: [22, 80, 443, 8000..9000],
-            # output_file: "path/to/masscan.bin"
-          )
+          output_file = Ronin::Masscan.scan do |masscan|
+            masscan.ips         = ARGV
+            # masscan.ports       = [22, 80, 443, 8000..9000]
+            # masscan.output_file = "path/to/masscan.bin"
+          end
         RUBY
       )
     end
@@ -230,18 +230,18 @@
       context "and when given the '--scanner' option" do
         let(:argv) { super() + %w[--scanner] }
 
-        it "must generate a new file containing a new `Ronin::Masscan.scan(...)` instead" do
+        it "must generate a new file containing a new `Ronin::Masscan.scan` instead" do
           expect(File.read(path)).to eq(
             <<~RUBY
               #!/usr/bin/env ruby
 
               require 'ronin/masscan'
 
-              output_file = Ronin::Masscan.scan(
-                *ARGV,
-                # ports: [22, 80, 443, 8000..9000],
-                # output_file: "path/to/masscan.bin"
-              )
+              output_file = Ronin::Masscan.scan do |masscan|
+                masscan.ips         = ARGV
+                # masscan.ports       = [22, 80, 443, 8000..9000]
+                # masscan.output_file = "path/to/masscan.bin"
+              end
             RUBY
           )
         end
@@ -258,11 +258,11 @@
 
             require 'ronin/masscan'
 
-            output_file = Ronin::Masscan.scan(
-              *ARGV,
-              # ports: [22, 80, 443, 8000..9000],
-              # output_file: "path/to/masscan.bin"
-            )
+            output_file = Ronin::Masscan.scan do |masscan|
+              masscan.ips         = ARGV
+              # masscan.ports       = [22, 80, 443, 8000..9000]
+              # masscan.output_file = "path/to/masscan.bin"
+            end
 
             output_file.each do |record|
               p record
@@ -282,11 +282,11 @@
 
             require 'ronin/masscan'
 
-            output_file = Ronin::Masscan.scan(
-              *ARGV,
-              # ports: [22, 80, 443, 8000..9000],
-              # output_file: "path/to/masscan.bin"
-            )
+            output_file = Ronin::Masscan.scan do |masscan|
+              masscan.ips         = ARGV
+              # masscan.ports       = [22, 80, 443, 8000..9000]
+              # masscan.output_file = "path/to/masscan.bin"
+            end
 
             Ronin::DB.connect
             Ronin::Masscan::Importer.import(output_file)
@@ -299,18 +299,18 @@
       let(:file) { 'path/to/masscan.bin' }
       let(:argv) { ['--output-file', file] }
 
-      it "must add an `output_file:` keyword argument to `Ronin::Masscan.scan(...)` with the given file" do
+      it "must add an `masscan.output_file =` keyword argument to `Ronin::Masscan.scan` with the given file" do
         expect(File.read(path)).to eq(
           <<~RUBY
             #!/usr/bin/env ruby
 
             require 'ronin/masscan'
 
-            output_file = Ronin::Masscan.scan(
-              *ARGV,
-              # ports: [22, 80, 443, 8000..9000],
-              output_file: #{file.inspect}
-            )
+            output_file = Ronin::Masscan.scan do |masscan|
+              masscan.ips         = ARGV
+              # masscan.ports       = [22, 80, 443, 8000..9000]
+              masscan.output_file = #{file.inspect}
+            end
           RUBY
         )
       end
@@ -320,18 +320,18 @@
       let(:ports) { [22, 80, 443] }
       let(:argv)  { ['--ports', "#{ports.join(',')}"] }
 
-      it "must add an `ports:` keyword argument to `Ronin::Masscan.scan(...)` with an Array of the given port numbers" do
+      it "must add an `masscan.ports =` keyword argument to `Ronin::Masscan.scan` with an Array of the given port numbers" do
         expect(File.read(path)).to eq(
           <<~RUBY
             #!/usr/bin/env ruby
 
             require 'ronin/masscan'
 
-            output_file = Ronin::Masscan.scan(
-              *ARGV,
-              ports: #{ports.inspect},
-              # output_file: "path/to/masscan.bin"
-            )
+            output_file = Ronin::Masscan.scan do |masscan|
+              masscan.ips         = ARGV
+              masscan.ports       = #{ports.inspect}
+              # masscan.output_file = "path/to/masscan.bin"
+            end
           RUBY
         )
       end
@@ -353,18 +353,18 @@
         ['--ports', "#{start_port1}-#{stop_port1},#{start_port2}-#{stop_port2}"]
       end
 
-      it "must add an `ports:` keyword argument to `Ronin::Masscan.scan(...)` with an Array of the given port ranges" do
+      it "must add an `masscan.ports =` keyword argument to `Ronin::Masscan.scan` with an Array of the given port ranges" do
         expect(File.read(path)).to eq(
           <<~RUBY
             #!/usr/bin/env ruby
 
             require 'ronin/masscan'
 
-            output_file = Ronin::Masscan.scan(
-              *ARGV,
-              ports: #{ports.inspect},
-              # output_file: "path/to/masscan.bin"
-            )
+            output_file = Ronin::Masscan.scan do |masscan|
+              masscan.ips         = ARGV
+              masscan.ports       = #{ports.inspect}
+              # masscan.output_file = "path/to/masscan.bin"
+            end
           RUBY
         )
       end
@@ -390,18 +390,18 @@
         ['--ports', "#{port1},#{port2},#{start_port1}-#{stop_port1},#{start_port2}-#{stop_port2}"]
       end
 
-      it "must add an `ports:` keyword argument to `Ronin::Masscan.scan(...)` with an Array of the given port numbers and ranges" do
+      it "must add an `masscan.ports =` keyword argument to `Ronin::Masscan.scan` with an Array of the given port numbers and ranges" do
         expect(File.read(path)).to eq(
           <<~RUBY
             #!/usr/bin/env ruby
 
             require 'ronin/masscan'
 
-            output_file = Ronin::Masscan.scan(
-              *ARGV,
-              ports: #{ports.inspect},
-              # output_file: "path/to/masscan.bin"
-            )
+            output_file = Ronin::Masscan.scan do |masscan|
+              masscan.ips         = ARGV
+              masscan.ports       = #{ports.inspect}
+              # masscan.output_file = "path/to/masscan.bin"
+            end
           RUBY
         )
       end

spec/masscan_spec.rb

@@ -18,17 +18,32 @@
   describe '.scan' do
     let(:ips) { '192.168.1.1' }
 
-    context 'when ip adresses are not given' do
-      it 'must raise an ArgumentError' do
-        expect {
-          subject.scan
-        }.to raise_error(ArgumentError, 'must specify at least one IP address')
+    let(:expected_output_filename) { %r{#{Ronin::Masscan::CACHE_DIR}\/masscan[^.]+\.json} }
+
+    context 'when IPs are given as arguments' do
+      it 'must pass the IPs to the `masscan` command' do
+        expect(Kernel).to receive(:system).with({}, 'masscan', '-p', '80', '--output-filename', match(expected_output_filename), ips).and_return(true)
+
+        subject.scan(ips, ports: 80)
       end
     end
 
-    context 'when masscan command was successful' do
-      let(:expected_output_filename) { %r{#{Ronin::Masscan::CACHE_DIR}\/masscan[^.]+\.json} }
+    context "when IPs are not given as arguments" do
+      context "but a block is given" do
+        context "and the IPs are set in the block" do
+          it 'must pass the IPs to the `masscan` command' do
+            expect(Kernel).to receive(:system).with({}, 'masscan', '-p', '80', '--output-filename', match(expected_output_filename), ips).and_return(true)
 
+            subject.scan do |masscan|
+              masscan.ports = 80
+              masscan.ips   = ips
+            end
+          end
+        end
+      end
+    end
+
+    context 'when masscan command was successful' do
       before do
         allow(Kernel).to receive(:system).with({}, 'masscan', '-p', '80', '--output-filename', match(expected_output_filename), ips).and_return(true)
       end