Add support for DTLS

bin/coap

@@ -17,6 +17,8 @@ Usage: #{File.basename($0)} [options] <method> <uri>
                                   STDOUT or a file path.
   --payload, -p         <string>  Payload for POST and PUT as string.
   --payload-file, -f    <file>    Read payload for POST and PUT from file.
+  --identity-file, -i   <file>    Read DTLS identity from file.
+  --key-file, -k        <file>    Read DTLS PSK form file.
   --type, -t            <type>    Message type (con, non, ack, rst).
   --help, -h                      This usage message.
 
@@ -27,6 +29,8 @@ end
 METHODS = CoAP::METHODS + [:observe]
 
 opts = GetoptLong.new(
+  ['--identity-file',   '-i', GetoptLong::REQUIRED_ARGUMENT],
+  ['--key-file',        '-k', GetoptLong::REQUIRED_ARGUMENT],
   ['--content-format',  '-c', GetoptLong::REQUIRED_ARGUMENT],
   ['--debug',           '-d', GetoptLong::NO_ARGUMENT],
   ['--output',          '-o', GetoptLong::REQUIRED_ARGUMENT],
@@ -36,13 +40,18 @@ opts = GetoptLong.new(
   ['--help',            '-h', GetoptLong::NO_ARGUMENT]
 )
 
-$DEBUG  = false
-output  = nil
-payload = nil
-options = {}
+$DEBUG   = false
+output   = nil
+payload  = nil
+options  = {}
+initopts = {}
 
 opts.each do |opt, arg|
   case opt
+  when '--identity-file'
+    initopts[:dtls_id] = File.read(arg)
+  when '--key-file'
+    initopts[:dtls_key] = File.read(arg)
   when '--content-format'
     cf = CoAP::Registry.convert_content_format(arg)
     options[:content_format] = cf
@@ -78,7 +87,7 @@ uri = URI.parse(uri)
 
 usage unless uri.scheme[/^coap/]
 
-client = CoAP::Client.new
+client = CoAP::Client.new(initopts)
 
 answer = case method
 when :get

lib/core/coap/client.rb

@@ -11,7 +11,8 @@ class Client
       #                   (maximum retransmission count, default 4),
       #                   recv_timeout (timeout for ACK responses, default: 2),
       #                   host (destination host), post (destination port,
-      #                   default 5683).
+      #                   default 5683), dtls_id (DTLS client identity)
+      #                   and dtls_key (DTLS pre-shared key).
       def initialize(options = {})
         @max_payload = options[:max_payload] || 256
 
@@ -25,8 +26,18 @@ def initialize(options = {})
 
       # Enable DTLS socket.
       def use_dtls
-        require 'CoDTLS'
-        @options[:socket] = CoDTLS::SecureSocket
+        require 'tinydtls'
+
+        id  = @options[:dtls_id]
+        key = @options[:dtls_key]
+
+        if id.nil? or key.nil?
+          raise ArgumentError.new("DTLS support requires specification of an identity/key pair")
+        end
+
+        @options[:socket] = TinyDTLS::UDPSocket.new
+        @options[:socket].add_client(id, key)
+
         self
       end
 
@@ -267,7 +278,12 @@ def decode_uri(uri)
         @logger.debug 'URI decoded: ' + uri.inspect
         fail ArgumentError, 'Invalid URI' if uri.nil?
 
-        uri
+        scheme = uri.first
+        if scheme == "coaps"
+          self.use_dtls
+        end
+
+        uri.drop(1)
       end
 
       def initialize_message(method, path, query = nil, payload = nil)

lib/core/coap/coding.rb

@@ -89,10 +89,17 @@ def scheme_and_authority_encode(host, port)
       end
 
       def scheme_and_authority_decode(s)
-        if s =~ %r{\A(?:coap://)((?:\[|%5B)([^\]]*)(?:\]|%5D)|([^:/]*))(:(\d+))?(/.*)?\z}i
-          host = $2 || $3       # Should check syntax...
-          port = $5 || CoAP::PORT
-          [$6, host, port.to_i]
+        if s =~ %r{\A(?:(coap|coaps)://)((?:\[|%5B)([^\]]*)(?:\]|%5D)|([^:/]*))(:(\d+))?(/.*)?\z}i
+          scheme = $1 || "coap"
+          host   = $3 || $4       # Should check syntax...
+          port   = $6
+
+          if port.nil?
+            port = scheme == "coap" ?
+              CoAP::PORT : CoAP::PORT_DTLS
+          end
+
+          [scheme, $7, host, port.to_i]
         end
       end
 

test/test_message.rb

@@ -71,10 +71,12 @@ def test_scheme_and_authority_encode
   end
 
   def test_scheme_and_authority_decode
-    assert_equal [nil, "foo.bar", 4711], CoRE::CoAP.scheme_and_authority_decode("coap://foo.bar:4711")
-    assert_equal [nil, "foo.bar", 5683], CoRE::CoAP.scheme_and_authority_decode("coap://foo.bar")
-    assert_equal [nil, "foo:bar", 4711], CoRE::CoAP.scheme_and_authority_decode("coap://[foo:bar]:4711")
-    assert_equal [nil, "foo:bar", 5683], CoRE::CoAP.scheme_and_authority_decode("coap://%5Bfoo:bar%5D")
+    assert_equal ["coap", nil, "foo.bar", 4711], CoRE::CoAP.scheme_and_authority_decode("coap://foo.bar:4711")
+    assert_equal ["coap", nil, "foo.bar", 5683], CoRE::CoAP.scheme_and_authority_decode("coap://foo.bar")
+    assert_equal ["coap", nil, "foo:bar", 4711], CoRE::CoAP.scheme_and_authority_decode("coap://[foo:bar]:4711")
+    assert_equal ["coap", nil, "foo:bar", 5683], CoRE::CoAP.scheme_and_authority_decode("coap://%5Bfoo:bar%5D")
+
+    assert_equal ["coaps", nil, "foo.bar", 5684], CoRE::CoAP.scheme_and_authority_decode("coaps://foo.bar")
   end
 
   def test_coap_message