Ssh transport for network device management

It is an adapatation of net-ssh-telnet, so that net-ssh conforms to
a saner interface for consumer.

Signed-off-by: Brice Figureau <brice-puppet@daysofwonder.com>

2 files changed, 119 insertions, 0 deletions

diff --git a/lib/puppet/feature/ssh.rb b/lib/puppet/feature/ssh.rb
new file mode 100644
index 000000000..82fe19882
--- /dev/null
+++ b/lib/puppet/feature/ssh.rb
@@ -0,0 +1,4 @@
+require 'puppet/util/feature'
+
+Puppet.features.rubygems?
+Puppet.features.add(:ssh, :libs => %{net/ssh})
diff --git a/lib/puppet/util/network_device/transport/ssh.rb b/lib/puppet/util/network_device/transport/ssh.rb
new file mode 100644
index 000000000..b3cf51b8a
--- /dev/null
+++ b/lib/puppet/util/network_device/transport/ssh.rb
@@ -0,0 +1,115 @@
+
+require 'puppet/util/network_device'
+require 'puppet/util/network_device/transport'
+require 'puppet/util/network_device/transport/base'
+require 'net/ssh'
+
+# This is an adaptation/simplification of gem net-ssh-telnet, which aims to have
+# a sane interface to Net::SSH. Credits goes to net-ssh-telnet authors
+class Puppet::Util::NetworkDevice::Transport::Ssh < Puppet::Util::NetworkDevice::Transport::Base
+
+  attr_accessor :buf, :ssh, :channel, :verbose
+
+  def initialize
+    super
+  end
+
+  def handles_login?
+    true
+  end
+
+  def eof?
+    !! @eof
+  end
+
+  def connect(&block)
+    @output = []
+    @channel_data = ""
+
+    begin
+      Puppet.debug("connecting to #{host} as #{user}")
+      @ssh = Net::SSH.start(host, user, :port => port, :password => password, :timeout => timeout)
+    rescue TimeoutError
+      raise TimeoutError, "timed out while opening an ssh connection to the host"
+    end
+
+    @buf = ""
+    @eof = false
+    @channel = nil
+    @ssh.open_channel do |channel|
+      channel.request_pty { |ch,success| raise "failed to open pty" unless success }
+
+      channel.send_channel_request("shell") do |ch, success|
+        raise "failed to open ssh shell channel" unless success
+
+        ch.on_data { |ch,data| @buf << data }
+        ch.on_extended_data { |ch,type,data|  @buf << data if type == 1 }
+        ch.on_close { @eof = true }
+
+        @channel = ch
+        expect(default_prompt, &block)
+        # this is a little bit unorthodox, we're trying to escape
+        # the ssh loop there while still having the ssh connection up
+        # otherwise we wouldn't be able to return ssh stdout/stderr
+        # for a given call of command.
+        return
+      end
+
+    end
+    @ssh.loop
+
+  end
+
+  def close
+    @channel.close if @channel
+    @channel = nil
+    @ssh.close if @ssh
+  end
+
+  def expect(prompt)
+    line = ''
+    sock = @ssh.transport.socket
+
+    while not @eof
+      break if line =~ prompt and @buf == ''
+      break if sock.closed?
+
+      IO::select([sock], [sock], nil, nil)
+
+      process_ssh
+
+      # at this point we have accumulated some data in @buf
+      # or the channel has been closed
+      if @buf != ""
+        line += @buf.gsub(/\r\n/no, "\n")
+        @buf = ''
+        yield line if block_given?
+      elsif @eof
+        # channel has been closed
+        break if line =~ prompt
+        if line == ''
+          line = nil
+          yield nil if block_given?
+        end
+        break
+      end
+    end
+    Puppet.debug("ssh: expected #{line}") if @verbose
+    line
+  end
+
+  def send(line)
+    Puppet.debug("ssh: send #{line}") if @verbose
+    @channel.send_data(line + "\n")
+  end
+
+  def process_ssh
+    while @buf == "" and not eof?
+      begin
+        @channel.connection.process(0.1)
+      rescue IOError
+        @eof = true
+      end
+    end
+  end
+end
\ No newline at end of file