HTTPS Proxy and LWP::UserAgent

Ted B picture Ted B · Aug 24, 2012 · Viewed 29.3k times · Source

I have read a number of threads on a number of sites and am still unable to make this work.

I have a client machine (OSX) with OpenSSL 0.9.8r running perl 5.12.4, with LWP 6.0.4, updated Crypt::SSLeay, Net::SSL etc. I am trying to connect to an HTTPS site (https://github.com in the example) via a WinGate proxy that I have running on a Windows VM. Note that my actual application is attaching to an SSL webservice that I have no control over.

From Firefox, pointed to the proxy everything is copacetic. The page loads successfully and I see the connections in the Proxy software Activity monitor. I'll be darned if I can make it work in Perl though. I've started with the code from this Stack Overflow Question : How do I force LWP to use Crypt::SSLeay for HTTPS requests? And added some debugging and additional output. Here's were I stand now:

#!/usr/bin/perl

use strict;
use warnings;
use Net::SSL (); # From Crypt-SSLeay

BEGIN {
  $Net::HTTPS::HTTPS_SSL_SOCKET_CLASS = "Net::SSL"; # Force use of Net::SSL
  $ENV{HTTPS_PROXY} = 'https://192.168.1.11:80';
#  $ENV{PERL_LWP_SSL_VERIFY_HOSTNAME} = 0;
  $ENV{HTTPS_DEBUG} = 1;  #Add debug output
}

use LWP::UserAgent;
my $ua = LWP::UserAgent->new();
my $req = HTTP::Request->new('GET','https://github.com/');
my $response = $ua->request($req);

print "--\n";
print "$_\n" for grep { $_ =~ /SSL/ } keys %INC;
print "--\n";

if ($response->is_success) {
     print $response->decoded_content;  # or whatever
     exit(0);
}
else {
 print "\nFail:\n";
     print $response->status_line ."\n";
     exit(1);
}

Here's the output from this code:

--
Crypt/SSLeay.pm
Crypt/SSLeay/X509.pm
Net/SSL.pm
--

Fail:
500 Can't connect to github.com:443 (Crypt-SSLeay can't verify hostnames)

If I then uncomment $ENV{PERL_LWP_SSL_VERIFY_HOSTNAME} = 0;, I do see a single connect to github.com:443 on the proxy and then nothing. (Note it works great from a web browser through the proxy). After much hanging I get the following output from the script:

SSL_connect:before/connect initialization
SSL_connect:SSLv2/v3 write client hello A
SSL_connect:before/connect initialization
SSL_connect:SSLv3 write client hello A
SSL_connect:failed in SSLv3 read server hello A
SSL_connect:before/connect initialization
SSL_connect:SSLv2 write client hello A
SSL_connect:failed in SSLv2 read server hello A
--
Crypt/SSLeay.pm
Crypt/SSLeay/X509.pm
Net/SSL.pm
Crypt/SSLeay/CTX.pm
Crypt/SSLeay/MainContext.pm
--

Fail:
500 SSL negotiation failed: 

If anyone can provide some direction here I would greatly appreciate it!

Answer

Markus Benning picture Markus Benning · Jul 22, 2013

I just uploaded the LWP::Protocol::connect module to CPAN. This module adds the missing HTTP/CONNECT method support to LWP.

  use LWP::UserAgent;

  $ua = LWP::UserAgent->new(); 
  $ua->proxy('https', 'connect://proxyhost.domain:3128/');

  $ua->get('https://www.somesslsite.com');

With this module you can use the regular IO::Socket::SSL implementation for LWP >=6.00.