can_read issue with Net::SSL [rt.cpan.org #98898]

Migrated from rt.cpan.org#98898 (status was 'open')

Requestors:

• hv@crypt.org

From hv@crypt.org on 2014-09-15 13:09:32
:

My $work app has encountered a problem that I believe is identical to
rt#81237, but with Net::SSL rather than IO::Socket::SSL as the underlying
socket library.

Our current plan to address this is to upgrade to latest Crypt::SSLeay
(which exposed the 'pending' method in a recent change) and then apply
the following local patch (against Net-HTTP-6.06, but should apply over
6.07 as well):

--- lib/perl5/Net/HTTP/Methods.pm.old   2013-03-10 22:35:43.000000000 +0000
+++ lib/perl5/Net/HTTP/Methods.pm   2014-09-15 14:05:38.000000000 +0100
@@ -284,6 +284,7 @@
     my $self = shift;
     return 1 unless defined(fileno($self));
     return 1 if $self->isa('IO::Socket::SSL') && $self->pending;
+    return 1 if $self->isa('Net::SSL') && $self->pending;

     # With no timeout, wait forever.  An explict timeout of 0 can be
     # used to just check if the socket is readable without waiting.

It looks like the support for pending() came in between 0.65_02 and 0.65_04
of Crypt::SSLeay, so it isn't obvious how Net::HTTP should incorporate
a similar fix - if you're using an older Crypt::SSLeay you'll get something
like:
  Can't locate object method "pending" via package "LWP::Protocol::https::Socket" at lib/perl5/Net/HTTP/Methods.pm line 287.

Hugo

From http://xlogon.net/amock on 2014-10-15 12:48:54
:

Hi all,

I'm pretty sure that I was just hit by this bug too. 
I'm using LWP to make HTTP POST requests to a site. 

The following combination works fast as expected:

Net::HTTP 6.01
Crypt::SSLeay 0.57
IO::Socket::INET 1.31

The follwoing combination does return after a long period (timeout):
Net::HTTP 6.06 also 6.07
Crypt::SSLeay 0.57
IO::Socket::INET 1.31

I found the same portion of code with profiling the weired test run with Devel::NYTProf showing that the call to can_read spent most of the time.

Following the proposed patch I installed newest Crypt::SSLeay and Net::HTTP, added the line and the measured runtime is as expected.

I'm writing this because I'm pretty sure that this bug happens in the wild and is a kind of backward compatibility regression of Net::HTTP.
Important is that the method 'pending' of 'Net::SSL' is introduced in one of the younger versions. The right dependencies must be set.

Regards
McA

From http://xlogon.net/amock on 2014-10-15 14:34:21
:

As an addendum:
I did some research on that to find a solution to my problem. It seems that the usage of Net::SSL as part of Crypt::SSLeay to make SSL connections is deprecated (version 0.72). As soon as you install that version the module LWP::Protocol::https is pulled from CPAN if it's not installed before. With that installation IO::Socket::SSL should be pulled from CPAN to do the whole SSL stuff in favour of Net::SSL.

So, as soon as you hit the bug you should check why you're using Net::SSL and not IO::Socket::SSL. In my case is seems to be a strange history of dependency resolution.

Regards
McA

Start in lib/perl5/Net/HTTP/Methods.pm at can_read, and compare the existing IO::Socket::SSL handling with the reported Net::SSL case. Check how older Crypt::SSLeay versions expose socket methods and determine a backward-compatible resolution for the pending call. Done means Net::SSL connections no longer hang or fail with older supported dependencies.