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rubyftpftps

Connect to uncertified host via FTP over TLS/SSL


A vendor I grab a file from is changing from FTP to FTP over SSL.

I am trying to update my code from net/ftp to net/ftptls

The new host I need to connect to is not certified and my script reports back this error.

hostname was not match with the server certificate

The vendor will not fix this.

Looking at /usr/lib/ruby/1.8/net/ftptls.rb I thought it wouldn't be too hard to monkey-patch FTPTLS to ignore the untrusted host.

I tried changing verify_mode to OpenSSL::SSL::VERIFY_NONE and commenting out the post_connection_check` line.

neither worked.

Any thoughts on how to do this?

require 'socket'
require 'openssl'
require 'net/ftp'

module Net
  class FTPTLS < FTP
    def connect(host, port=FTP_PORT)
      @hostname = host
      super
    end

    def login(user = "anonymous", passwd = nil, acct = nil)
       store = OpenSSL::X509::Store.new
       store.set_default_paths
       ctx = OpenSSL::SSL::SSLContext.new('SSLv23')
       ctx.cert_store = store
       ctx.verify_mode = OpenSSL::SSL::VERIFY_PEER
       ctx.key = nil
       ctx.cert = nil
       voidcmd("AUTH TLS")
       @sock = OpenSSL::SSL::SSLSocket.new(@sock, ctx)
       @sock.connect
       @sock.post_connection_check(@hostname)
       super(user, passwd, acct)
       voidcmd("PBSZ 0")
    end
  end
end

Solution

  • This may be the world's slowest answer, but I ran across your question and it helped my fix it myself, so I wanted to post for posterity.

    You were very close, you just need to also comment out #post_connection_check.

    What I did, rather than monkeypatching ruby itself, was bring a copy of this into /lib of my project.

    module Net
    
      class FTPTLS < FTP
        def connect(host, port=FTP_PORT)
          @hostname = host
          super
        end
    
        def login(user = "anonymous", params = {:password => nil, :acct => nil, :ignore_cert => false})
          store = OpenSSL::X509::Store.new
          store.set_default_paths
          ctx = OpenSSL::SSL::SSLContext.new('SSLv23')
          ctx.cert_store = store
          ctx.verify_mode = params[:ignore_cert] ? OpenSSL::SSL::VERIFY_NONE : OpenSSL::SSL::VERIFY_PEER
          ctx.key = nil
          ctx.cert = nil
          voidcmd("AUTH TLS")
          @sock = OpenSSL::SSL::SSLSocket.new(@sock, ctx)
          @sock.connect
          @sock.post_connection_check(@hostname) unless params[:ignore_cert]
          super(user, params[:password], params[:acct])
          voidcmd("PBSZ 0")
        end
      end
    end
    

    I also cleaned up the param passing a bit. You would use this like so:

      require 'ftptls'  # Use my local version, not net/ftptls
      @ftp_connection = Net::FTPTLS.new()
      @ftp_connection.passive = true
      @ftp_connection.connect(host, 21)
      @ftp_connection.login('user', :password => 'pass', :ignore_cert => true)
    

    HTH