Upload SSL Key to GitHub when activating private repository

lib/travis/api/v3/github.rb

@@ -49,5 +49,15 @@ module Travis::API::V3
         gh.post(hooks_url, payload)
       end
     end
+
+    def upload_key(repository)
+      keys_path = "repos/#{repository.slug}/keys"
+      key = gh[keys_path].
+        detect { |e| e['key'] == repository.key.encoded_public_key }
+
+      unless key
+        gh.post keys_path, title: Travis.config.host.to_s, key: repository.key.encoded_public_key
+      end
+    end
   end
 end

lib/travis/api/v3/models/repository.rb

@@ -12,6 +12,7 @@ module Travis::API::V3
     belongs_to :last_build, class_name: 'Travis::API::V3::Models::Build'.freeze
     belongs_to :current_build, class_name: 'Travis::API::V3::Models::Build'.freeze
 
+    has_one :key, class_name: 'Travis::API::V3::Models::SSLKey'.freeze
     has_one :default_branch,
       foreign_key: [:repository_id, :name],
       primary_key: [:id,  :default_branch],

lib/travis/api/v3/models/ssl_key.rb

@@ -1,5 +1,29 @@
 module Travis::API::V3
   class Models::SSLKey < Model
     belongs_to :repository
+
+    serialize :private_key, Travis::API::V3::Extensions::EncryptedColumn.new
+
+    def encoded_public_key
+      key = build_key.public_key
+      ['ssh-rsa ', "\0\0\0\assh-rsa#{sized_bytes(key.e)}#{sized_bytes(key.n)}"].pack('a*m').gsub("\n", '')
+    end
+
+    private
+
+      def build_key
+        @build_key ||= OpenSSL::PKey::RSA.new(private_key)
+      end
+
+      def sized_bytes(value)
+        bytes = to_byte_array(value.to_i)
+        [bytes.size, *bytes].pack('NC*')
+      end
+
+      def to_byte_array(num, *significant)
+        return significant if num.between?(-1, 0) and significant[0][7] == num[7]
+        to_byte_array(*num.divmod(256)) + significant
+      end
+
   end
 end

lib/travis/api/v3/services/repository/enable.rb

@@ -1,7 +1,14 @@
 module Travis::API::V3
   class Services::Repository::Enable < Services::Repository::Disable
     def run!
-      super(true)
+      repository = super(true)
+
+      if repository.private?
+        admin = access_control.admin_for(repository)
+        github(admin).upload_key(repository)
+      end
+
+      repository
     end
 
     def check_access(repository)