Support TLS certificate & key pair

Author: UXabre

docs/index.asciidoc

@@ -287,7 +287,9 @@ This plugin supports the following configuration options plus the
 | <<plugins-{type}s-{plugin}-ilm_policy>> |<<string,string>>|No
 | <<plugins-{type}s-{plugin}-ilm_rollover_alias>> |<<string,string>>|No
 | <<plugins-{type}s-{plugin}-index>> |<<string,string>>|No
+| <<plugins-{type}s-{plugin}-tls_certificate>> |a valid filesystem path|No
 | <<plugins-{type}s-{plugin}-keystore>> |a valid filesystem path|No
+| <<plugins-{type}s-{plugin}-tls_private_key>> |a valid filesystem path|No
 | <<plugins-{type}s-{plugin}-keystore_password>> |<<password,password>>|No
 | <<plugins-{type}s-{plugin}-manage_template>> |<<boolean,boolean>>|No
 | <<plugins-{type}s-{plugin}-parameters>> |<<hash,hash>>|No
@@ -628,6 +630,24 @@ Logstash uses
 http://www.joda.org/joda-time/apidocs/org/joda/time/format/DateTimeFormat.html[Joda
 formats] for the index pattern from event timestamp.
 
+[id="plugins-{type}s-{plugin}-tls_certificate"]
+===== `tls_certificate`
+
+  * Value type is <<path,path>>
+  * There is no default value for this setting.
+
+The tls_certificate used to present a client certificate to the server.
+It accepts .pem formatted files
+
+[id="plugins-{type}s-{plugin}-tls_private_key"]
+===== `tls_private_key`
+
+  * Value type is <<path,path>>
+  * There is no default value for this setting.
+
+The tls_private_key used to present a client private key to the server, to be used in conjunction with tls_certificate.
+It accepts .pkcs8 formatted files
+
 
 [id="plugins-{type}s-{plugin}-keystore"]
 ===== `keystore`

lib/logstash/outputs/elasticsearch/http_client_builder.rb

@@ -112,13 +112,21 @@ def self.setup_ssl(logger, params)
 
       return {:ssl => {:enabled => false}} if params["ssl"] == false
 
-      cacert, truststore, truststore_password, keystore, keystore_password =
-        params.values_at('cacert', 'truststore', 'truststore_password', 'keystore', 'keystore_password')
+      cacert, truststore, truststore_password, keystore, keystore_password, tls_certificate, tls_private_key =
+        params.values_at('cacert', 'truststore', 'truststore_password', 'keystore', 'keystore_password', 'tls_certificate', 'tls_private_key')
 
       if cacert && truststore
         raise(LogStash::ConfigurationError, "Use either \"cacert\" or \"truststore\" when configuring the CA certificate") if truststore
       end
 
+      if tls_certificate && keystore
+        raise(LogStash::ConfigurationError, "Use either \"tls_certificate\" or \"keystore\" when configuring the client certificate")
+      end
+
+      if (tls_private_key && !tls_certificate) || (tls_certificate && !tls_private_key)
+        raise(LogStash::ConfigurationError, "Both a \"tls_private_key\" and a \"tls_certificate\" need to be present")
+      end
+
       ssl_options = {:enabled => true}
 
       if cacert
@@ -131,7 +139,11 @@ def self.setup_ssl(logger, params)
       if keystore
         ssl_options[:keystore] = keystore
         ssl_options[:keystore_password] = keystore_password.value if keystore_password
+      elsif tls_certificate && tls_private_key
+        ssl_options[:client_cert] = tls_certificate
+        ssl_options[:client_key] = tls_private_key
       end
+
       if !params["ssl_certificate_verification"]
         logger.warn [
                        "** WARNING ** Detected UNSAFE options in elasticsearch output configuration!",

lib/logstash/plugin_mixins/elasticsearch/api_configs.rb

@@ -66,6 +66,11 @@ def self.included(mod)
       # Set the keystore password
       mod.config :keystore_password, :validate => :password
 
+      # The certificate to present to the server. (only pem format supported)
+      mod.config :tls_certificate, :validate => :path
+      # The private key to present to the server. (only pkcs8 format supported)
+      mod.config :tls_private_key, :validate => :path
+
       # This setting asks Elasticsearch for the list of all cluster nodes and adds them to the hosts list.
       # Note: This will return ALL nodes with HTTP enabled (including master nodes!). If you use
       # this with master nodes, you probably want to disable HTTP on them by setting

spec/unit/outputs/elasticsearch_ssl_spec.rb

@@ -77,6 +77,89 @@
       end.and_call_original
       subject.register
     end
+  end
+
+  context "when using both pem-encoded and jks-encoded client certificates" do
+    let(:tls_certificate) { Stud::Temporary.file.path }
+    let(:tls_private_key) { Stud::Temporary.file.path }
+    before do
+      `openssl req -x509  -batch -nodes -newkey rsa:2048 -keyout #{tls_private_key} -out #{tls_certificate}`
+    end
+
+    after :each do
+      File.delete(tls_private_key)
+      File.delete(tls_certificate)
+      subject.close
+    end
 
+    subject do
+      settings = {
+        "hosts" => "node01",
+        "ssl" => true,
+        "tls_certificate" => tls_certificate,
+        "tls_private_key" => tls_private_key,
+        # just any file will do for this test
+        "keystore" => tls_certificate
+      }
+      next LogStash::Outputs::ElasticSearch.new(settings)
+    end
+
+    it "should fail to load the plugin" do
+      expect { subject.register }.to raise_error(LogStash::ConfigurationError)
+    end
+  end
+  
+  context "when configuring only tls_certificate but ommitting the private_key" do
+    let(:tls_certificate) { Stud::Temporary.file.path }
+    let(:tls_private_key) { Stud::Temporary.file.path }
+    before do
+      `openssl req -x509  -batch -nodes -newkey rsa:2048 -keyout #{tls_private_key} -out #{tls_certificate}`
+    end
+
+    after :each do
+      File.delete(tls_private_key)
+      File.delete(tls_certificate)
+      subject.close
+    end
+
+    subject do
+      settings = {
+        "hosts" => "node01",
+        "ssl" => true,
+        "tls_certificate" => tls_certificate,
+      }
+      next LogStash::Outputs::ElasticSearch.new(settings)
+    end
+
+    it "should fail to load the plugin" do
+      expect { subject.register }.to raise_error(LogStash::ConfigurationError)
+    end
+  end
+
+  context "when configuring only private_key but ommitting the tls_certificate" do
+    let(:tls_certificate) { Stud::Temporary.file.path }
+    let(:tls_private_key) { Stud::Temporary.file.path }
+    before do
+      `openssl req -x509  -batch -nodes -newkey rsa:2048 -keyout #{tls_private_key} -out #{tls_certificate}`
+    end
+
+    after :each do
+      File.delete(tls_private_key)
+      File.delete(tls_certificate)
+      subject.close
+    end
+
+    subject do
+      settings = {
+        "hosts" => "node01",
+        "ssl" => true,
+        "tls_private_key" => tls_private_key,
+      }
+      next LogStash::Outputs::ElasticSearch.new(settings)
+    end
+
+    it "should fail to load the plugin" do
+      expect { subject.register }.to raise_error(LogStash::ConfigurationError)
+    end
   end
 end