cn 5 years ago
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+ 3
- 0
.gitignore View File

@@ -0,0 +1,3 @@
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+.DS_Store
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+*.lock
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+pkg/*

+ 8
- 0
.travis.yml View File

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+language: ruby
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+
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+rvm:
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+  - 2.0.0
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+  - 1.9.3
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+
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+gemfile:
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+  - Gemfile

+ 3
- 0
Gemfile View File

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+source 'https://rubygems.org'
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+
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+gemspec

+ 187
- 0
LICENSE View File

@@ -0,0 +1,187 @@
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+ 9
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README.md View File

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+# dyndnsd.rb
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+
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+[![Build Status](https://travis-ci.org/cmur2/dyndnsd.png)](https://travis-ci.org/cmur2/dyndnsd)
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+
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+A small, lightweight and extensible DynDNS server written with Ruby and Rack.
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+
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+## License
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+
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+dyndnsd.rb is licensed under the Apache License, Version 2.0. See LICENSE for more information.

+ 6
- 0
Rakefile View File

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+require 'bundler/gem_tasks'
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+require 'rspec/core/rake_task'
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+
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+RSpec::Core::RakeTask.new(:spec)
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+
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+task :default => :spec

+ 4
- 0
bin/dyndnsd View File

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+
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+require 'dyndnsd'
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+
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+Dyndnsd::Daemon.run!

+ 29
- 0
dyndnsd.gemspec View File

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+
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+$:.push File.expand_path("../lib", __FILE__)
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+
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+require 'dyndnsd/version'
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+
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+Gem::Specification.new do |s|
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+  s.name  = 'dyndnsd'
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+  s.version = Dyndnsd::VERSION
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+  s.summary = 'dyndnsd.rb'
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+  s.description = 'A small, lightweight and extensible DynDNS server written with Ruby and Rack.'
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+  s.author  = 'Christian Nicolai'
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+  s.email = 'chrnicolai@gmail.com'
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+  s.license = 'Apache License Version 2.0'
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+  s.homepage  = 'https://github.com/cmur2/dyndnsd'
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+
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+  s.files = `git ls-files`.split($/)
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+  s.test_files = s.files.grep(%r{^(test|spec|features)/})
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+
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+  s.require_paths = ['lib']
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+
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+  s.executables = ['dyndnsd']
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+
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+  s.add_runtime_dependency 'rack'
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+
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+  s.add_development_dependency 'bundler', '~> 1.3'
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+  s.add_development_dependency 'rake'
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+  s.add_development_dependency 'rspec'
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+  s.add_development_dependency 'rack-test'
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+end

+ 127
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lib/dyndnsd.rb View File

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+#!/usr/bin/env ruby
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+
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+require 'logger'
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+require 'ipaddr'
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+require 'json'
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+require 'yaml'
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+require 'rack'
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+
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+require 'dyndnsd/generator/bind'
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+require 'dyndnsd/updater/command_with_bind_zone'
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+require 'dyndnsd/responder/rest_style'
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+require 'dyndnsd/database'
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+require 'dyndnsd/version'
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+
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+module Dyndnsd
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+  def self.logger
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+    @logger
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+  end
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+
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+  def self.logger=(logger)
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+    @logger = logger
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+  end
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+
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+  class LogFormatter
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+    def call(lvl, time, progname, msg)
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+      "%s: %s\n" % [lvl, msg.to_s]
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+    end
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+  end
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+
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+  class Daemon
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+    def initialize(config, db, updater, responder)
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+      @users = config['users']
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+      @db = db
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+      @updater = updater
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+      @responder = responder
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+
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+      @db.load
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+      @db['serial'] ||= 1
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+      @db['hosts'] ||= {}
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+      (@db.save; update) if @db.changed?
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+    end
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+    
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+    def update
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+      @updater.update(@db)
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+    end
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+    
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+    def call(env)
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+      return @responder.response_for(:method_forbidden) if env["REQUEST_METHOD"] != "GET"
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+      return @responder.response_for(:not_found) if env["PATH_INFO"] != "/nic/update"
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+      
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+      params = Rack::Utils.parse_query(env["QUERY_STRING"])
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+      
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+      return @responder.response_for(:hostname_missing) if not params["hostname"]
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+      
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+      hostname = params["hostname"]
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+      
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+      # Check if hostname(s) match rules
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+      #return @responder.response_for(:hostname_malformed) if XY
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+      
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+      user = env["REMOTE_USER"]
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+      
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+      return @responder.response_for(:host_forbidden) if not @users[user]['hosts'].include? hostname
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+      
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+      # no myip?
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+      if not params["myip"]
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+        params["myip"] = env["REMOTE_ADDR"]
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+      end
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+      
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+      # malformed myip?
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+      begin
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+        IPAddr.new(params["myip"], Socket::AF_INET)
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+      rescue ArgumentError
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+        params["myip"] = env["REMOTE_ADDR"]
74
+      end
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+      
76
+      myip = params["myip"]
77
+      
78
+      @db['hosts'][hostname] = myip    
79
+      
80
+      if @db.changed?
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+        @db['serial'] += 1
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+        @db.save
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+        update
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+        return @responder.response_for(:good)
85
+      end
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+      
87
+      @responder.response_for(:nochg)
88
+    end
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+
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+    def self.run!
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+      Dyndnsd.logger = Logger.new(STDOUT)
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+      Dyndnsd.logger.formatter = LogFormatter.new
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+
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+      if ARGV.length != 1
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+        puts "Usage: dyndnsd config_file"
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+        exit 1
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+      end
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+
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+      config_file = ARGV[0]
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+
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+      if not File.file?(config_file)
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+        Dyndnsd.logger.fatal "Config file not found!"
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+        exit 1
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+      end
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+
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+      Dyndnsd.logger.info "DynDNSd version #{Dyndnsd::VERSION}"
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+      Dyndnsd.logger.info "Using config file #{config_file}"
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+
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+      config = YAML::load(File.open(config_file, 'r') { |f| f.read })
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+
111
+      db = Database.new(config['db_file'])
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+      updater = Updater::CommandWithBindZone.new(config['updater_params']) if config['updater'] == 'command_with_bind_zone'
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+      responder = Responder::RestStyle.new
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+      
115
+      app = Daemon.new(config, db, updater, responder)
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+      app = Rack::Auth::Basic.new(app, "DynDNS") do |user,pass|
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+        (config['users'].has_key? user) and (config['users'][user]['password'] == pass)
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+      end
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+
120
+      Signal.trap('INT') do
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+        Rack::Handler::WEBrick.shutdown
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+      end
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+
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+      Rack::Handler::WEBrick.run app, :Host => config['host'], :Port => config['port']
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+    end
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+  end
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+end

+ 32
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lib/dyndnsd/database.rb View File

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+
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+require 'forwardable'
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+
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+module Dyndnsd
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+  class Database
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+    extend Forwardable
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+    
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+    def_delegators :@db, :[], :[]=, :each, :has_key?
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+  
10
+    def initialize(db_file)
11
+      @db_file = db_file
12
+    end
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+    
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+    def load
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+      if File.file?(@db_file)
16
+        @db = JSON.load(File.open(@db_file, 'r') { |f| f.read })
17
+      else
18
+        @db = {}
19
+      end
20
+      @db_hash = @db.hash
21
+    end
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+    
23
+    def save
24
+      File.open(@db_file, 'w') { |f| JSON.dump(@db, f) }
25
+      @db_hash = @db.hash
26
+    end
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+    
28
+    def changed?
29
+      @db_hash != @db.hash
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+    end
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+  end
32
+end

+ 29
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lib/dyndnsd/generator/bind.rb View File

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+
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+module Dyndnsd
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+  module Generator
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+    class Bind
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+      def initialize(config)
6
+        @ttl = config['ttl']
7
+        @origin = config['origin']
8
+        @dns = config['dns']
9
+        @email_addr = config['email_addr']
10
+      end
11
+
12
+      def generate(zone)
13
+        out = []
14
+        out << "$TTL #{@ttl}"
15
+        out << "$ORIGIN #{@origin}"
16
+        out << ""
17
+        out << "@ IN SOA #{@dns} #{@email_addr} ( #{zone['serial']} 3h 5m 1w 1h )"
18
+        out << "@ IN NS #{@dns}"
19
+        out << ""
20
+        zone['hosts'].each do |hostname,ip|
21
+          name = hostname.chomp('.' + @origin[0..-2])
22
+          out << "#{name} IN A #{ip}"
23
+        end
24
+        out << ""
25
+        out.join("\n")
26
+      end
27
+    end
28
+  end
29
+end

+ 19
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lib/dyndnsd/responder/rest_style.rb View File

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1
+
2
+module Dyndnsd
3
+  module Responder
4
+    class RestStyle
5
+      def response_for(state)
6
+        # general http errors
7
+        return [405, {"Content-Type" => "text/plain"}, ["Method Not Allowed"]] if state == :method_forbidden
8
+        return [404, {"Content-Type" => "text/plain"}, ["Not Found"]] if state == :not_found
9
+        # specific errors
10
+        return [422, {"Content-Type" => "text/plain"}, ["Hostname missing"]] if state == :hostname_missing
11
+        return [403, {"Content-Type" => "text/plain"}, ["Forbidden"]] if state == :host_forbidden
12
+        return [422, {"Content-Type" => "text/plain"}, ["Hostname malformed"]] if state == :hostname_malformed
13
+        # OKs
14
+        return [200, {"Content-Type" => "text/plain"}, ["Good"]] if state == :good
15
+        return [200, {"Content-Type" => "text/plain"}, ["No change"]] if state == :nochg
16
+      end
17
+    end
18
+  end
19
+end

+ 21
- 0
lib/dyndnsd/updater/command_with_bind_zone.rb View File

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+
2
+module Dyndnsd
3
+  module Updater
4
+    class CommandWithBindZone
5
+      def initialize(config)
6
+        @zone_file = config['zone_file']
7
+        @command = config['command']
8
+        @generator = Generator::Bind.new(config)
9
+      end
10
+      
11
+      def update(zone)
12
+        # write zone file in bind syntax
13
+        File.open(@zone_file, 'w') { |f| f.write(@generator.generate(zone)) }
14
+        # call user-defined command
15
+        pid = fork do
16
+          exec @command
17
+        end
18
+      end
19
+    end
20
+  end
21
+end

+ 4
- 0
lib/dyndnsd/version.rb View File

@@ -0,0 +1,4 @@
1
+
2
+module Dyndnsd
3
+  VERSION = "0.0.1"
4
+end

+ 87
- 0
spec/daemon_spec.rb View File

@@ -0,0 +1,87 @@
1
+require 'spec_helper'
2
+
3
+describe Dyndnsd::Daemon do
4
+  include Rack::Test::Methods
5
+  
6
+  def app
7
+    config = {
8
+      'users' => {
9
+        'test' => {
10
+          'password' => 'secret',
11
+          'hosts' => ['foo.example.org']
12
+        }
13
+      }
14
+    }
15
+    db = Dyndnsd::DummyDatabase.new({})
16
+    updater = Dyndnsd::Updater::Dummy.new
17
+    responder = Dyndnsd::Responder::RestStyle.new
18
+    app = Dyndnsd::Daemon.new(config, db, updater, responder)
19
+    
20
+    Rack::Auth::Basic.new(app, "DynDNS") do |user,pass|
21
+      (config['users'].has_key? user) and (config['users'][user]['password'] == pass)
22
+    end
23
+  end
24
+  
25
+  it 'requires authentication' do
26
+    get '/'
27
+    last_response.status.should == 401
28
+  end
29
+  
30
+  it 'only supports GET requests' do
31
+    authorize 'test', 'secret'
32
+    post '/nic/update'
33
+    last_response.status.should == 405
34
+  end
35
+  
36
+  it 'provides only the /nic/update' do
37
+    authorize 'test', 'secret'
38
+    get '/other/url'
39
+    last_response.status.should == 404
40
+  end
41
+  
42
+  it 'requires the hostname query parameter' do
43
+    authorize 'test', 'secret'
44
+    get '/nic/update'
45
+    last_response.status.should == 422
46
+  end
47
+  
48
+  it 'forbids changing hosts a user does not own' do
49
+    authorize 'test', 'secret'
50
+    get '/nic/update?hostname=notmyhost.example.org'
51
+    last_response.status.should == 403
52
+  end
53
+  
54
+  it 'updates a host on change' do
55
+    authorize 'test', 'secret'
56
+    
57
+    get '/nic/update?hostname=foo.example.org&myip=1.2.3.4'
58
+    last_response.should be_ok
59
+    
60
+    get '/nic/update?hostname=foo.example.org&myip=1.2.3.400'
61
+    last_response.should be_ok
62
+    last_response.body.should == 'Good'
63
+  end
64
+  
65
+  it 'returns no change' do
66
+    authorize 'test', 'secret'
67
+    
68
+    get '/nic/update?hostname=foo.example.org&myip=1.2.3.4'
69
+    last_response.should be_ok
70
+    
71
+    get '/nic/update?hostname=foo.example.org&myip=1.2.3.4'
72
+    last_response.should be_ok
73
+    last_response.body.should == 'No change'
74
+  end
75
+  
76
+  it 'forbids invalid hostnames' do
77
+    pending
78
+  end
79
+  
80
+  it 'outputs status per hostname' do
81
+    pending
82
+  end
83
+  
84
+  it 'supports multiple hostnames in request' do
85
+    pending
86
+  end
87
+end

+ 8
- 0
spec/spec_helper.rb View File

@@ -0,0 +1,8 @@
1
+
2
+require 'rubygems'
3
+require 'bundler/setup'
4
+require 'rack/test'
5
+
6
+require 'dyndnsd'
7
+require 'support/dummy_database'
8
+require 'support/dummy_updater'

+ 29
- 0
spec/support/dummy_database.rb View File

@@ -0,0 +1,29 @@
1
+
2
+require 'forwardable'
3
+
4
+module Dyndnsd
5
+  class DummyDatabase
6
+    extend Forwardable
7
+  
8
+    def_delegators :@db, :[], :[]=, :each, :has_key?
9
+
10
+    def initialize(db_init)
11
+      @db_init = db_init
12
+    end
13
+
14
+    def load
15
+      @db = @db_init
16
+      @db_hash = @db.hash
17
+    end
18
+
19
+    def save
20
+      @db_hash = @db.hash
21
+    end
22
+
23
+    def changed?
24
+      @db_hash != @db.hash
25
+    end
26
+  end
27
+end
28
+
29
+      

+ 10
- 0
spec/support/dummy_updater.rb View File

@@ -0,0 +1,10 @@
1
+
2
+module Dyndnsd
3
+  module Updater
4
+    class Dummy
5
+      def update(zone)
6
+        # nothing
7
+      end
8
+    end
9
+  end
10
+end