Merge branch 'master' of github.com:aderouineau/net-ssh into aderouineau-masteraderouineau-master

3 files changed, 47 insertions, 20 deletions

diff --git a/THANKS.txt b/THANKS.txt
index dc5b0ad..dbe8a7f 100644
--- a/THANKS.txt
+++ b/THANKS.txt
@@ -83,3 +83,4 @@ watsonian
 Grant Hutchins
 Michael Schubert
 mtrudel
+Aurélien Derouineau
diff --git a/lib/net/ssh/service/forward.rb b/lib/net/ssh/service/forward.rb
index 3b0face..0d5d55d 100644
--- a/lib/net/ssh/service/forward.rb
+++ b/lib/net/ssh/service/forward.rb
@@ -47,8 +47,12 @@ module Net; module SSH; module Service
     # If three arguments are given, it is as if the local bind address is
     # "127.0.0.1", and the rest are applied as above.
     #
+    # To request an ephemeral port on the remote server, provide 0 (zero) for
+    # the port number. In all cases, this method will return the port that
+    # has been assigned.
+    #
     #   ssh.forward.local(1234, "www.capify.org", 80)
-    #   ssh.forward.local("0.0.0.0", 1234, "www.capify.org", 80)
+    #   assigned_port = ssh.forward.local("0.0.0.0", 0, "www.capify.org", 80)
     def local(*args)
       if args.length < 3 || args.length > 4
         raise ArgumentError, "expected 3 or 4 parameters, got #{args.length}"
@@ -69,6 +73,7 @@ module Net; module SSH; module Service
         end
       end
 
+      local_port = socket.addr[1] if local_port == 0 # ephemeral port was requested
       remote_host = args.shift
       remote_port = args.shift.to_i
 
@@ -89,6 +94,8 @@ module Net; module SSH; module Service
           channel[:socket].close
         end
       end
+      
+      local_port
     end
 
     # Terminates an active local forwarded port. If no such forwarded port
@@ -120,15 +127,21 @@ module Net; module SSH; module Service
     # forwarded immediately. If the remote server is not able to begin the
     # listener for this request, an exception will be raised asynchronously.
     #
-    # If you want to know when the connection is active, it will show up in the
-    # #active_remotes list. If you want to block until the port is active, you
-    # could do something like this:
+    # To request an ephemeral port on the remote server, provide 0 (zero) for
+    # the port number. The assigned port will show up in the # #active_remotes
+    # list.
+    #
+    # If you want to block until the port is active, you could do something
+    # like this:
     #
-    #   ssh.forward.remote(80, "www.google.com", 1234, "0.0.0.0")
-    #   ssh.loop { !ssh.forward.active_remotes.include?([1234, "0.0.0.0"]) }
+    #   old_active_remotes = ssh.forward.active_remotes
+    #   ssh.forward.remote(80, "www.google.com", 0, "0.0.0.0")
+    #   ssh.loop { !(ssh.forward.active_remotes.length > old_active_remotes.length) }
+    #   assigned_port = (ssh.forward.active_remotes - old_active_remotes).first[0]
     def remote(port, host, remote_port, remote_host="127.0.0.1")
       session.send_global_request("tcpip-forward", :string, remote_host, :long, remote_port) do |success, response|
         if success
+          remote_port = response.read_long if remote_port == 0
           debug { "remote forward from remote #{remote_host}:#{remote_port} to #{host}:#{port} established" }
           @remote_forwarded_ports[[remote_port, remote_host]] = Remote.new(host, port)
         else
diff --git a/test/manual/test_forward.rb b/test/manual/test_forward.rb
index 8e27818..5794077 100644
--- a/test/manual/test_forward.rb
+++ b/test/manual/test_forward.rb
@@ -1,4 +1,4 @@
-#     $ ruby -Ilib -Itest -rrubygems test/test_forward.rb
+#     $ ruby -Ilib -Itest -rrubygems test/manual/test_forward.rb
 
 # Tests for the following patch:
 #
@@ -30,14 +30,6 @@ class TestForward < Test::Unit::TestCase
     [localhost ,ENV['USER'], {:keys => "~/.ssh/id_rsa", :verbose => :debug}]
   end
   
-  def find_free_port 
-    server = TCPServer.open(0)
-    server.setsockopt(Socket::SOL_SOCKET,Socket::SO_REUSEADDR,true)
-    port = server.addr[1]
-    server.close
-    port
-  end
-  
   def start_server_sending_lot_of_data(exceptions)
     server = TCPServer.open(0)
     Thread.start do
@@ -77,12 +69,34 @@ class TestForward < Test::Unit::TestCase
     return server
   end
   
+  def test_local_ephemeral_port_should_work_correctly
+    session = Net::SSH.start(*ssh_start_params)
+    
+    assert_nothing_raised do
+      assigned_port = session.forward.local(0, localhost, 22)
+      assert_not_nil assigned_port
+      assert_operator assigned_port, :>, 0
+    end
+  end
+  
+  def test_remote_ephemeral_port_should_work_correctly
+    session = Net::SSH.start(*ssh_start_params)
+    
+    assert_nothing_raised do
+      session.forward.remote(22, localhost, 0, localhost)
+      session.loop { !(session.forward.active_remotes.length > 0) }
+      assigned_port = session.forward.active_remotes.first[0]
+      assert_not_nil assigned_port
+      assert_operator assigned_port, :>, 0
+    end
+  end
+  
   def test_loop_should_not_abort_when_local_side_of_forward_is_closed
     session = Net::SSH.start(*ssh_start_params) 
     server_exc = Queue.new
     server = start_server_sending_lot_of_data(server_exc)
     remote_port = server.addr[1]
-    local_port = find_free_port
+    local_port = 0 # request ephemeral port
     session.forward.local(local_port, localhost, remote_port)
     client_done = Queue.new
     Thread.start do
@@ -104,7 +118,7 @@ class TestForward < Test::Unit::TestCase
     server_exc = Queue.new    
     server = start_server_sending_lot_of_data(server_exc)
     remote_port = server.addr[1]
-    local_port = find_free_port
+    local_port = 0 # request ephemeral port
     session.forward.local(local_port, localhost, remote_port)
     client_done = Queue.new
     Thread.start do
@@ -163,7 +177,7 @@ class TestForward < Test::Unit::TestCase
     session = Net::SSH.start(*ssh_start_params)    
     server = start_server_closing_soon
     remote_port = server.addr[1]
-    local_port = find_free_port
+    local_port = 0 # request ephemeral port
     session.forward.local(local_port, localhost, remote_port)
     client_done = Queue.new
     Thread.start do
@@ -203,8 +217,7 @@ class TestForward < Test::Unit::TestCase
     client_exception = Queue.new
     client_data = Queue.new
     remote_port = server.addr[1]
-    local_port = find_free_port
-    session.forward.local(local_port, localhost, remote_port)
+    local_port = session.forward.local(0, localhost, remote_port)
     Thread.start do
       begin
         client = TCPSocket.new(localhost, local_port)